Book of Abstracts

Book of Abstracts

  Nº ISBN -13 : 978-84-695-3180-8   Nº REG: 201239654

40 International Conference on Valencia, Spain 9 - 13 September, 2012

Coordination Chemistry

Book of Abstracts

40th International Conference on Coordination Chemistry

WELCOME

On behalf of the Organizing Committee we have the pleasure to warmly welcome you to Valencia for the ICCC40. Located on the Spanish Mediterranean coast,Valencia is a city where old historical places in their downtown area are joined by state-of-the-art architecture, as shown in the Ciudad de las Artes y las Ciencias (“City of the Arts and Sciences) or in the Palacio de Congresos, where the conference will be held. ICCC is the longest-running conference series in the field of Coordination Chemistry. It started in 1950 and has now become a premiere venue for discussion of the latest developments in this area of chemistry.We are glad to bring ICCC back to Europe for the first time since 2002 (the most recent editions took place in Heidelberg, Germany, 2002; Merida, Mexico, 2004; Cap Town, South Africa, 2006; Jerusalem, Israel, 2008; and Adelaide, Australia, 2010). ICCC40 has attracted more than 900 participants from all over the world to discuss on the use of coordination chemistry to design new functional molecules and supramolecular materials exhibiting useful chemical, physical or biological properties. Some key topics include the design and applications of metal-organic frameworks; the crystal engineering of supramolecular functional materials; the molecular design of homogeneous and heterogeneous catalysts; the design of coordination compounds for energy and environmental applications; the molecular nanoscience; the use of metals in medicine and protein design. We thank all participants for attending this conference to present their latest results and to discuss the future research trends in Coordination Chemistry. We hope you enjoy the social and scientific programs and wish you a pleasant stay in Valencia.

The Organizing Committee of ICCC40

III

40th International Conference on Coordination Chemistry

SPONSORS ORGANIZER

SPONSORS



PLENARY LECTURE SPONSORS

Sponsoring Prof. Craig Hill’s Plenary Lecture

Sponsoring Prof. Roberta Sessoli’s Plenary Lecture

Sponsoring Prof. Edward Solomon’s Plenary Lecture

IV



International Union of Pure and Applied Chemistry (IUPAC)

40th International Conference on Coordination Chemistry

BURSARY SPONSORS







SPECIAL PRIZE SPONSORS





MICROSYMPOSIA SPONSORS

Sponsoring “Metals in Medicine” microsymposia







Sponsoring “ Coordination Compounds: Synthesis, Structure and Bonding” microsymposia

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40th International Conference on Coordination Chemistry

COMMITTEES CHAIRMAN Eugenio CORONADO (Universitat de València, ICMol,Valencia, Spain)

CO-CHAIRMAN Santiago ALVAREZ (Universitat de Barcelona, Barcelona, Spain)

INTERNATIONAL COMMITTEE Andy HOR (University of Singapore, Singapore) Steve LINCOLN (University of Adelaide, Adelaide, Australia) Dan MEYERSTEIN (Ben-Gurion University of the Negev, Beer-Sheva, Israel) Chris ORVIG (University of British Columbia,Vancouver, Canada) Lahcene OUAHAB (University of Rennes 1, Rennes, France) Jan REEDIJK (Leiden University, The Netherlands) Masahiro YAMASHITA (Tohoku University, Japan)

NATIONAL ADVISORY COMMITTEE Mercé CAPDEVILA (Universidad Autónoma de Barcelona, Spain) Ernesto CARMONA (Universidad de Sevilla, Spain) Enrique COLACIO (Universidad de Granada, Spain) José M. DOMINGEZ VERA (Universidad de Granada, Spain) Albert ESCUER (Universidad de Barcelona, Spain) Miguel A. ESTERUELAS (Instituto de Ciencia de los Materiales, Universidad de Zaragoza-CSIC, Spain) Manuel GARCÍA BASALLOTE (Universidad de Cádiz, Spain) José R. GALÁN MASCARÓS (Instituto Catalán de Investigación Química Tarragona, Spain) María A. GARRALDA (Universidad del Pais Vasco, Spain)

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40th International Conference on Coordination Chemistry

José GIMENO (Universidad de Oviedo, Spain) Félix JALÓN (Universidad de Castilla la Mancha, Spain) Reyes JIMÉNEZ APARICIO (Universidad Complutense de Madrid, Spain) Antonio LAGUNA (Instituto de Ciencia de los Materiales, Universidad de Zaragoza-CSIC, Spain) Agustí LLEDOS (Universidad Autónoma de Barcelona, Spain) Antoni LLOBET (Instituto Catalán de Investigación Química, Tarragona, Spain) Rosa M. LLUSAR (Universitat Jaume I, Castellón, Spain) Ramón MARTÍNEZ MÁÑEZ (Universidad Politéncica de Valencia, Spain) Pedro J. PÉREZ (Universidad de Huelva, Spain) Josep Maria POBLET (Universitat Rovira i Virgili, Tarragona, Spain) Luis A. ORO (Universidad de Zaragoza, Spain) Eliseo RUIZ (Universidad de Barcelona, Spain) Felix ZAMORA (Universidad Autónoma de Madrid, Spain)

LOCAL ORGANIZING COMMITTEE Juan M. CLEMENTE JUAN (Universitat de València, ICMol,Valencia, Spain) Miguel CLEMENTE LEON (Universitat de València, ICMol,Valencia, Spain) Alicia FORMENT-ALIAGA (Universitat de València, ICMol,Valencia, Spain) Enrique GARCÍA ESPAÑA (Universitat de València, ICMol,Valencia, Spain) Carlos GIMENEZ SAIZ (Universitat de València, ICMol,Valencia, Spain) Carlos J. GOMEZ GARCÍA (Universitat de València, ICMol,Valencia, Spain) Miguel JULVE (Universitat de València, ICMol,Valencia, Spain) Francisco LLORET (Universitat de València, ICMol,Valencia, Spain) Guillermo MINGUEZ ESPALLARGAS (Universitat de València, ICMol,Valencia, Spain) José A. REAL (Universitat de València, ICMol,Valencia, Spain) Francisco M. ROMERO (Universitat de València, ICMol,Valencia, Spain)

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40th International Conference on Coordination Chemistry

TABLE OF CONTENTS PLENARY LECTURES MICROSYMPOSIA (Keynote, invited and contributed lectures) A) MATERIALS 1.

MOLECULAR MAGNETISM

2.

MATERIALS FOR ENERGY

3.

METAL-ORGANIC FRAMEWORKS (MOFs)

4.

MULTIFUNCTIONAL MATERIALS

B) NANOSCIENCE 1.

SUPRAMOLECULAR NANOSCIENCE & SENSING

2.

POLYOXOMETALATE NANOSCIENCE

3.

MOLECULAR ELECTRONICS & SURFACE SCIENCE

C) REACTIVITY AND CATALISYS 1.

CHEMISTRY & ENVIRONMENT

2.

HOMOGENEOUS CATALYTIC REACTIONS

3.

COORDINATION COMPOUNDS: SYNTHESIS, STRUCTURE AND BONDING

D) BIOINORGANIC CHEMISTRY 1.

METALS IN MEDICINE

2.

METAL IONS AND NUCLEIC ACIDS

3.

METAL IONS AND PROTEINS

4.

BIOMATERIALS

POSTERS IX

9 - 13 September 2012

PL01

PL02

Twenty years of Single Molecule Magnets: where to from here? Roberta Sessoli,a Dipartimento di Chimica ‘Ugo Schiff’, Università degli Studi di Firenze, 50019 Sesto Fiorentino, Firenze (Italy). E-mail: [email protected]

Interlocked Host Molecules for Anion Recognition and Sensing Paul D. Beer,a Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK. E-mail: [email protected]

Twenty years have elapsed since the discovery of slow relaxation of the magnetization and the related magnetic hysteresis in [Mn12O12(O2CCH3)16(H2O)4]. [1] The first ten years have been characterized by an intense research mainly in condensed matter physics, as Single Molecule Magnets have represented the ideal toys to investigate quantum effects in nanomagnetism. The field seems far to see its sunset, as demonstrated by recent results on the magnetic coherence on another archetypal SMM, the evergreen Fe8 cluster. [2] The last ten years have been mainly characterized by an intense research activity in coordination chemistry with the aim to enhance the anisotropy energy barrier responsible for the bistability. [3] The interest has gradually shifted to 4f and 5f elements, with significant achievements, [4] far superior than those obtained with heavier transition elements. The rationalization of magnetic anisotropy for these ions is very demanding from the computational side but interesting results have been obtained. For instance, despite the internal nature of the 4f magnetic orbitals, covalency and subtle structural details cannot be neglected when investigating lanthanide ions. [5] The field of SMM has also experienced the general trend towards “nano” and the efforts have been focused on the organization of molecules on surfaces to address them individually. Although the comparison with atomic structures, e.g. adatoms manipulated on surfaces, suggests the last ones are better candidate for addressing the magnetism of single sub-nanometric objects, [6] the knowledge acquired with SMMs becomes now of great use to understand the magnetism of atomic nanostructures. Moreover, the observation of magnetic bistability in isolated molecules grafted on conducting surfaces [7] has open the possibility to exploit the great advantage of the spontaneous assembly of molecules on surfaces to develop a new molecular spintronics. Extending the assembly of Single Molecule Magnets to magnetic and superconducting surfaces opens the fascinating scenario of a new hybrid magnetism.

Inspired by the fundamental roles negatively charged species play in a range of chemical, biological, medical and environmental processes, the field of anion supramolecular chemistry has expanded enormously during the past few decades. Although many acyclic and macrocyclic two-dimensional receptors have shown success in the binding and sensing of anions, it can be argued that the challenge of recognising anions selectively in protic solvents necessitates the construction of more elaborate three dimensional receptors where the binding site is in a protected buried pocket, which enables the total encapsulation of the anionic guest species. Taking this into account we surmised that the construction of such sophisticated target receptors would require unprecedented innovative anion templation synthetic methodologies. Various serendipitous discoveries of where anions have been shown to control the assembly of polymetallic cluster and cage complexes abound in the literature,[1] however, the strategic use of anions as potential templating reagents for the designed assembly of molecular architectures remains largely underdeveloped.[2] In spite of the huge interest being currently shown in the construction of mechanically bonded molecules for nanotechnological applications as molecular switches and machines, the potential of their unique topological cavities in host-guest chemistry has been in the main neglected.[3] This is especially the case for the recognition of anions. The lecture will describe the development of a general anion templation strategy which has been successfully exploited for the synthesis of a variety of rotaxane and catenane molecular host systems whose three dimensional interlocked binding domain cavities exhibit high degrees of anion selectivity in competitive aqueous solvent mixtures.[4] With the objective of constructing anion sensors, the incorporation of redox- and photo-active groups into these interlocked frameworks has also been undertaken and our latest results will be discussed.[5]

[1] Sessoli, R.; Gatteschi, D.; Caneschi, A.; Novak, M. A. Nature 1993, 365, 141. [2] Takahashi, S.; Tupitsyn, I. S.; van Tol, J.; Beedle, C. C.; Hendrickson, D. N.; Stamp, P. C. E. Nature 2011, 476, 76. [3] Milios, C. J.; Vinslava, A.; Wernsdorfer, W.; Moggach, S.; Parsons, S.; Perlepes, S. P.; Christou, G.; Brechin, E. K. J. Am. Chem. Soc. 2007, 129, 2754. [4] Rinehart, J. D.; Fang, M.; Evans, W. J.; Long, J. R. Nature Chem. 2011, 3, 538. [5] Cucinotta, G.; Perfetti, M.; Luzon, J.; Etienne, M.; Car, P. E.; Caneschi, A.; Calvez, G.; Bernot, K.; Sessoli, R. Angew. Chem. Int. Ed. 2012, 51, 1606. [6] Loth, S.; Baumann, S.; Lutz, C. P.; Eigler, D. M.; Heinrich, A. J. Science 2012, 335, 196. [7] Mannini, M.; Pineider, F.; Sainctavit, P.; Danieli, C.; Otero, E.; Sciancalepore, C.; Talarico, A. M.; Arrio, M. A.; Cornia, A.; Gatteschi, D.; Sessoli, R. Nature Mater. 2009, 8, 194.

Keywords: Single Molecule anisotropy, lanthanides

Magnets

(SMMs),

magnetic

[1] R. Vilar, Struct. Bond. 2008, 129, 175-206. [2] M. Lankshear, P. D. Beer, Acc. Chem. Res. 2007, 40, 657-668; B. Huang, S. M. Santos, V. Felix, P. D. Beer, Chem. Commun. 2008, 4610-4612. [3] M. J. Chmielewski, J. J. Davis, P. D. Beer, Org. Biomol. Chem. 2009, 7, 415-424. [4] L. M. Hancock, L. C. Gilday, C. J. Serpell, N. L. Kilah, S. Carvalho, P. J. Costa, V. Felix, P. D. Beer, Chem. Eur. J. 2010, 16, 13082-13094; N. L. Kilah, M. D. Wise, C. J. Serpell, A. L. Thompson, N. G. White, K. E. Christensen, P. D. Beer, J. Am. Chem. Soc., 2010, 132, 11893-11895; N. H. Evans, C. J. Serpell, P. D. Beer, Angew. Chem. Int. Ed. 2011, 50, 2507-2510. [5] N. H. Evans, C. J. Serpell, P. D. Beer, Chem. Commun., 2011, 47, 8775-8777; N. H. Evans, H. Rahman, A. V. Leontiev, N. D. Greenham, G. A. Orlowski, Q. Zeng, R. M. J. Jacobs, C. J. Serpell, N. L. Kilah, J. J. Davis, P. D. Beer, Chem. Sci. 2012, 3, 1080-1089; A. Caballero, F. Zapata, N. G. White, P. J. Costa, V. Felix, P. D. Beer, Angew. Chem. Int. Ed. 2012, 51, 1876-1880.

Keywords: anions, supramolecular chemistry, sensing

XIII

PL

Plenary Lectures

Plenary Lectures PL03

PL04

Robust Tunable Water Oxidation Catalysts and Nanostructures for Solar Fuels Craig L. Hill, Department of Chemistry, Emory University. E-mail: [email protected]

Progress in the Chemistry of Metallabenzenes and Metallabenzynes Guochen Jia, Department of Chemistry,The Hong Kong University of Science and Technology, (Hong Kong). E-mail: [email protected]

Even conservative projections for global energy demand indicate that we will not have sufficient energy to “power the planet” by midcentury. Combustion of fossil fuel supplies the great majority of energy for most countries, and extensive research is making the deleterious environmental consequences of this increasingly certain. Solar energy is the only renewable with the potential capacity to meet mankind’s growing energy needs. Finally, much future energy must be in high density forms, i.e. fuels, and not just electricity (from photovoltaics) or heat, because aircraft, ships and other energy-intensive major parts of the global economy require high-density energy. Thus realizing entities to produce solar fuel is an international priority, with the principal focus on water splitting (H2O + sunlight → H2 + 1/2O2) and/ or CO2 reduction (CO2 + 2H2O + sunlight → CH3OH + O2). Our group continues to work in several areas, and I will summarize our latest work and re-interpretation of noble metal oxo compounds, but our main current focus is solar fuel chemistry. While photoelectrochemical, solar-thermal and other approaches to solar fuels largely involve the solid state, the opportunities in this area to coordination chemists are major. Solar fuel generation requires three unit operations regardless of the platform or approach (photoelectrochemical cells, nanodevices, etc.): (1) a light absorber or photosensitizer that generates a long-lived charge-separated excited state; (2) a catalyst for reduction of H2O or CO2 to produce fuel molecules; and (3) a water oxidation catalyst (WOC). For viability, these unit operations (compounds or structures) must work effectively together and be extremely stable. We have designed and realized different inorganic molecules that execute all these operations with many positive features. Our photosensitizers and catalysts largely use polyoxometalates (POMs) as ligands to bring together multiple reaction centers. A core design concept is that appropriate POMs represent the most thermodynamically stable form of these elements in water over certain pH ranges. In these ranges, metal oxide particles or films convert to our POMs; outside these ranges the opposite happens. After our development of the first carbon-free WOCs, [{Ru4O4(OH)2(H4O)4}(g-SiW10O36)2]10- [1,2] and [Co4(H2O)2(αPW9O34)2]10- [3] we have designed and prepared several more that are extremely stable with one, [Co4(H2O)2(α-VW9O34)2]10- (to be published shortly) that turns far over faster than the oxygen evolving center (OEC), although with a higher overpotential. In addition, we are developing H2O and CO2 reduction catalysts as well as carbonfree photosensitizer systems,[4] all based on tunable and stable multi-transition-metal POMs. We will describe the X-ray structures, electronic structures, redox features and catalytic properties of all these POM-based solar fuel generating units and put these efforts in the larger context of coordination chemistry for green energy. We thank the U.S. DOE (WOCs and molecular photosensitizers) and the U.S. NSF (reduction catalysts) for funding. [1] Y. V. Geletii, et al. Angew. Chem. Int. Ed., 2008, 47, 3896-3899. [2] A. Sartorel, et al J. Am. Chem. Soc, 2008, 130, 5006-5007. [3] Q. Yin, et al. Science, 2010, 328, 342-345. [4] C. Zhao, et al. J. Am. Chem. Soc., 2011, 133, 20134-20137.

Keywords: water oxidation catalysts, CO2 reduction catalysts, inorganic molecular photosensitizers

XIV

Metallabenzenes and metallabenzynes are transition-metal analogs of benzene and benzyne in which a CH group or C atom is replaced by an isolobal transition metal fragments. These compounds are interesting because they may show aromatic properties and could mediate organometallic reactions. In the past few years, we have engaged in the development of chemistry of these interesting class of organometallic compounds [1]. We have successfully isolated a series of new metallabenzenes (e.g. 1 and 2), metallabenzynes (e.g. 3 and 4) and metallanaphthynes (e.g. 5). We have also investigated the chemical properties of metallabenzynes. For example, we found that osmabenzynes, like organic aromatic compounds, could undergo electrophilic substitution reactions to give new osmabenzynes; react with nucleophiles to generate metallabenzene species through addition of nucleophile at the carbyne carbon of metallabenzynes; and undergo reductive elimination to give carbene complexes. In this presentation, recent progress we made in the synthesis and chemistry of metallabenzenes and metallabenzynes will be described.

[1] See for example: (a) Poon, K. C.; Liu, L.; Guo, T.; Li, J,; Sung, H. H. Y.; Williams, I. D.; Lin, Z.; Jia, G. Angew. Chem. Int. Ed. 2010, 49, 2759. (b) Hung, W. Y.; Liu, B.; Shou, W.; Wen, T. B.; Shi, C.; Sung, H. H. Y.; Williams, I. D.; Lin, Z.; Jia, G. J. Am. Chem. Soc. 2011, 113, 18350. (c) Chen, J.; Sung, H. H. Y.; Williams, I. D.; Lin, Z.; Jia, G. Angew. Chem. Int. Ed. 2011, 50, 10675. (d) Chen, J.; Shi, C.; Sung, H. H. Y.; Williams, I. D.; Lin, Z.; Jia, G. Angew. Chem. Int. Ed. 2011, 50, 7295.

Keywords: reactivity, metellaaromatics, metallabenzenes

PL05

PL06

Large Pore Apertures in a Series of Metal-Organic Frameworks Omar Yaghi, University of California at Berkeley and Lawrence Berkeley National Laboratory. E-mail: [email protected]

Geometric and Electronic Structure Contributions to Cu/O2 Reactivity Edward I. Solomon, Stanford University, Stanford, California (USA). E-mail: [email protected]

We report a strategy to expand the pore aperture of metal-organic frameworks (MOFs) into a previously unattained size regime [> 32 angstroms (Å)]. Specifically, the systematic expansion of a well-known MOF structure, MOF-74, from its original link of one phenylene ring (I) to two, three, four, five, six, seven, nine and eleven (II to XI, respectively) afforded an isoreticular series of MOF-74 structures (termed IRMOF-74-I to XI) with pore apertures ranging from 14 to 98 Å. All members of this series have non-interpenetrating structures and exhibit robust architectures as evidenced by their permanent porosity and high thermal stability (up to 300 °C). The pore apertures of an oligoethylene glycol functionalized IRMOF-74-VII and IRMOF-74IX are large enough for natural proteins to enter the pores.

Copper active sites in (Bio)Inorganic Chemistry are involved in reversible dioxygen binding, O2 activation for electrophilic aromatic attack and hydrogen atom abstraction, and the four electron reduction of O2 to water. These have unique spectroscopic features reflecting novel geometric and electronic structures that are key to reactivity. This presentation will provide an overview of this chemistry/spectroscopy/ electronic structure/reactivity and extend the concepts developed to the active site in oxygen-activated Cu/ZSM-5 which selectively oxidizes methane to methanol at low temperature. Keywords: Bioinorganic, Catalysis, Spectroscopy

XV

PL

Plenary Lectures

Plenary Lectures PL07

PL08

Artificial Photosynthesis for Sustainable Fuel Production Shunichi Fukuzumi, Department of Material and Life Science, Graduate School of Engineering, Osaka University, ALCA, Japan Science and Technology Agency (JST) (Japan). E-mail: fukuzumi@ chem.eng.osaka-u.ac.jp

Rotaxanes and catenanes in motion: from species in solution to crystals Jean-Pierre Sauvage, Institut de Science et Ingenierie Moleculaire (ISIS), 8 allee Gaspard Monge, F-67000 Strasbourg, (France). E-mail: [email protected]. Northwestern University, Department of Chemistry, 2145 Sheridan Road, Evanston, Illinois 60208-3113, (USA). E-mail: [email protected]

Sustainable and clean energy resources are highly required in order to solve global energy and environmental issues. Extensive efforts have so far been devoted to develop an artificial version of photosynthesis for sustainable fuel production. Artificial photosynthesis consists of several steps: light harvesting, charge-separation and catalytic processes for water oxidation and reduction as well as CO2 fixation. Hydrogen has merited increasing attention as a clean, inexhaustible, efficient and cost-attractive energy carrier for the future. However, because gaseous hydrogen is difficult to store and transport, formic acid that is a two-electron reduction product of CO2 with hydrogen and also hydrogen peroxide can be alternative sustainable clean energy resources. Hydrogen peroxide can be obtained by photocatalytic oxidation of water by O2. This lecture presents recent development on each step of artificial photosynthesis and the overall photocatalytic water oxidation and reduction for sustainable fuel production. A rational design of the photosynthetic reaction center models has been made based on the Marcus theory of electron transfer. A variety of photosynthetic reaction center models composed of electron donors and acceptors linked by covalent and non-covalent bonding have been developed including multi-component systems, which undergo efficient charge separation, electron or hole migration and slow charge recombination.[1,2] An electron donor-acceptor has also been developed, affording the long-lived charge-separated state with high energy inside nano-sized mesoporous silica alumina.[3] Efficient photocatalytic hydrogen evolution has been achieved by combination of simple electron donor-acceptor dyads with metal nanoparticles including non-precious metals.[3] Efficient catalysts for interconversion between hydrogen and formic acid in water at ambient temperature and pressure have also been developed for hydrogen storage by fixation of CO2 with hydrogen as a form of formic acid (liquid) that can be converted back to hydrogen whenever needed.[4] We have also developed highly efficient photocatalytic olefin epoxidation and alkane hydroxylation by using manganese porphyrins as catalysts, [Ru(bpy)3]2+ (bpy = 2,2’-bipyridine) as a photosensitizer, [CoIII(NH3)5Cl]2+ as a weak one-electron oxidant, and water as an oxygen source.5 The photocatalytic water oxidation to produce hydrogen peroxide as a sustainable chemical fuel will also be reported together with the development of hydrogen peroxide fuel cell. [1] (a) S. Fukuzumi, Phys. Chem. Chem. Phys. 2008, 10, 2283. (b) S. Fukuzumi, S., K. Ohkubo, J. Mater. Chem. 2012, 22, 4575. [2] S. Fukuzumi, K. Doi, T. Suenobu, K. Ohkubo, Y. Yamada, K. D. Karlin, Proc. Natl. Acad. Sci. USA 2012, in press. [3] (a) Y. Yamada, T. Miyahigashi, H. Kotani, K. Ohkubo, S. Fukuzumi, J. Am. Chem. Soc. 2011, 133, 16136. (b) Y. Yamada, T. Miyahigashi, H. Kotani, H., K. Ohkubo, S. Fukuzumi, Energy Environ. Sci. 2012, 5, 6111. [4] (a) Y. Maenaka, T. Suenobu, S. Fukuzumi, Energy Environ. Sci. 2012, 5, in press. (b) Y. Maenaka, T. Suenobu, S. Fukuzumi, J. Am. Chem. Soc. 2012, 134, 367. [5] S. Fukuzumi, T. Kishi, H. Kotani, Y.-M. Lee, W. Nam, Nature Chem. 2011, 3, 38.

Keywords: formic acid, hydrogen , hydrogen peroxide

XVI

Catenanes and rotaxanes have attracted much interest in molecular chemistry, first as pure synthetic challenges and, more recently, as components of functional materials. The synthesis of such compounds relies on templates (transition metals or organic assemblies). In recent years, two-dimensional interlocking arrays have been designed and elaborated. The transition metal template (copper(I)) plays an essential role : several metal centres are combined with several organic fragments so as to lead to multicomponent assemblies, the various organic components being threaded or interlocked with one another. Separately, the field of artificial molecular machines has experienced a spectacular development, in relation to molecular devices at the nanometric level or as mimics of biological motors. A few recent examples are based on multi-rotaxanes acting as “molecular compressors” or “switchable receptors”. A recent system from the Strasbourg group, behaving as a switchable receptor, consists of two bis-macrocycles threaded by two rods. The [4] rotaxane obtained incorporates two porphyrinic “plates” located at the centre of each bis-macrocycle between which various substrates can be complexed. Another example is that of a [3] rotaxane whose two rings act as flapping wings, as illustrated below:

In the frame of a collaborative project with the research groups of Prof. Yaghi and Prof. Stoddart, new Metal-Organic Frameworks (MOFs) have been synthesised and studied, which contain interlocking systems. Here again, the role of copper is determining. The new materials obtained are promising in terms of electrochemical and dynamic properties, paving the way to molecular machineincorporating MOFs. A few recent references: [1] R. S. Forgan, J.-P. Sauvage, J. F. Stoddart, Chem. Rev., 2011, 111, 54345464. [2] J.-P. Collin, F. Durola, J. Frey, V. Heitz, F. Reviriego, J.-P. Sauvage, Y. Trolez, K. Rissanen, J. Am. Chem. Soc. 2010, 132, 6840-6850. [3] A. Joosten, Y. Trolez, J.-P. Collin, V. Heitz, J.-P. Sauvage, J. Am. Chem. Soc., 2012, 134, 1802-1809. [4] A. Coskun, M. Hmadeh, G. Barin, F. Gàndara, Q. Li, E. Choi, N. L. Strutt, D. B. Cordes, A. M. Z. Slawin, J. F. Stoddart, J.-P. Sauvage, O. M. Yaghi, Angew. Chem. Int. Ed., 2012, 51, 2160-2163.

Keywords: copper(I), catenanes, molecular machines

9 - 13 September 2012

Microsymposia

Studies of Heterometallic Rings and Chains Richard E. P. Winpenny, School of Chemistry and Photon Science Institute, The University of Manchester, Oxford Road, Manchester M13 9PL, UK. E-mail: [email protected] Heterometallic rings are stable and easily variable complexes [1]. The main family we have been studying are octametallic, and normally contain {Cr7M} cores, where M = a divalent metal. The compounds are ideal for physical studies of magnetic behaviour, including EPR spectroscopy [2] and INS studies. It is also possible to link together the heterometallic rings to make dimers, trimers and tetramers of rings [3]. Here we will discuss recent studies that might include synthesis of metal-organic frameworks that contain rings as building blocks; detailed pulsed EPR studies of relaxation mechanisms; studies of frustrated odd-numbered rings.

Nakano,b Y. Murakami, H. Oshio, J. Am. Chem. Soc. 2011, 133, 3592 – 3600 [2] K. Mitsumoto, E. Oshiro, H. Nishikawa, T. Shiga, H. Oshio, Chem. Eur. J. 2011, 17, 9612-9818.

Keyword: multi-bistability

MS.A1.I1 Metal Phosphonates with Tunable Magnetic Properties Song-Song Bao, Li-Min Zheng, State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (PR China). E-mail: [email protected] Metal phosphonates have received an increasing attention in recent years owing to their potential applications in catalysis, ion exchange, proton conductivity and magnetic materials etc. Great efforts have been devoted to the preparation of metal phosphonate compounds with new architectures and properties. It is well known that the monophosphonic acids RPO3H2, where R represents an alkyl or aryl group, prefer to form layered structures with metal ions. By introducing functional groups such as carboxylate, macrocycle and additional phosphonate groups, we have succeeded in synthesizing novel homometallic and heterometallic phosphonate compounds with new structures and interesting physical and chemical properties. Particularly, the magnetic properties of metal phosphonates may be tuned by changing the interlayer distance, the packing modes of the layers and by external stimuli such as thermal treatment. In this presentation, we shall describe our recent efforts on the design and syntheses of paramagnetic metal phosphonates with tunable magentic properties. The modulation of the spin state of cobalt in 3d-4f heterometallic phosphonates CoIIILnIII-notp (notpH6 = 1,4,7-triazacyclononane-1,4,7-triyl-tris(methylenephosphonic acid) by the second metal and the possible mechanism will be discussed.

[1] M. Affronte, S. Carretta, G. A. Timco and R. E. P. Winpenny, Chem. Commun., 2007, 1789 - 1797. [2] S. Piligkos, H. Weihe, E. Bill, F. Neese, H. El Mkami, G. M. Smith, D. Collison, G. Rajaraman, G. A. Timco, R. E. P. Winpenny and E. J. L. McInnes, Chem. Eur. J., 2009, 15, 3152 – 3167. [3] G. A. Timco, T. B. Faust, F. Tuna and R. E. P. Winpenny, Chem. Soc. Rev., 2011, 40, 3067-3075.

Keywords: heterometallic, template, chromium

MS.A1.KN2 Metal Complexes with Multi-bistability Hiroki Oshio, University of Tsukuba, Graduate School of Pure and Applied Sciences, Department of Chemistry, Tsukuba (Japan). E-mail: [email protected] A bistable system can rest in two stable phases, at free energy minima, and switching between the phases can be acheived by the application of external stimuli. Bistable molecules have, therefore, attracted intense research interest due to their potential applications in molecular switches and memory devices, for which spin-crossover (SCO) and electron transfer–active chromophores are promising building blocks. Multi-component materials, in which each component possesses different bistability, are expected to show synergistic behaviors, such as stepped phase transition and selective excitation to meta-stable states. We present here multi-bistable systems showing i) stepped SCO transitions, ii) photo-induced single molecule magnetism, and iii) photo-induced single chain magnetism.

[1] G. K. H. Shimizu, R. Vaidhyanathan, J. M. Taylor, Chem. Soc. Rev. 2009, 38, 1430–1449. [2] S. Natarajan, S. Mandal, Angew. Chem. Int. Ed. 2008, 47, 4798 – 4828. [3] T.-H. Yang, Y. Liao, L.-M. Zheng, R. E. Dinnebier, Y.-H. Su, J. Ma, Chem. Commun. 2009, 3023–3025. [4] S.-S. Bao, Y. Liao, Y.-H. Su, X. Liang, F.-C. Hu, Z. Sun, L.-M. Zheng, S. Wei, R. Alberto, Y.-Z. Li, J. Ma, Angew. Chem. Int. Ed. 2011, 50, 5504 –5508.

Keywords: metal phosphonate, magnetic property, tunable

[1] M. Nihei, Y. Sekine, N. Suganami, K. Nakazawa, A. Nakao, H. Nakao, M.

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Microsymposia MS.A1.I2 Control of Uniaxial Anisotropy to Single-ion Magnet Song Gao, Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China). E-mail: [email protected] Single-molecule magnets (SMMs) and single-chain magnets (SCMs) have been received great attention for their unique properties since 1990s, such as slow relaxation and quantum tunnelling of magnetization, which offer the opportunity of potential application in high-density information storage and quantum computation at molecular level. However, the cluster-based SMMs face some challenges to increase of blocking temperature further: firstly complicated magnetic coupling within cluster often leads to unexpected magnetic ground state; secondly different easy axis orientation for individual magnetic center within cluster usually results in a small overall uniaxial anisotropy for the whole cluster molecule. Therefore it is very difficulty to control the magnetic ground state and uniaxial anisotropy for a multicenter cluster molecule for the enhancement of anisotropic energy barrier. To simplify the questions and to rational control the uniaxial anisotropy of a magnetic molecule, we are going to explore the smallest molecular entity with isolated single spin center showing SMM or SMM-like behavior, named single-ion magnets (SIMs). This study is also crucial in understanding the nature of the local anisotropy of SMMs and SCMs. Due to the prominent spin−orbit coupling effect, several lanthanide- and actinide-containing mononuclear molecules were discovered to be SIMs. It was proposed that the high-order uniaxial ligand field was able to generate the Ising-type degenerated ground state with low-lying excited states in the 102 cm−1 energy scale, which can give rise to uniaxial anisotropy and possibly make these molecules behave as high anisotropic energy barriers. The singleion feature of these molecular nanomagnets makes them close to the microscopic scale compared with typical cluster-based SMMs, and as a result the quantum aspects seem more prominent in SIMs. Three series of lanthanide mononuclear molecules, one family of single-paramagnetic centered transition metal compounds, and their SMM behaviors will be presented. (1) β-diketone dysprosium(III) complexes with D4d approximate local symmetry; [1] (2) lanthanide organometallic mixed sandwich molecules, (Cp*)Ln(COT), where Cp* is the pentamethylcyclopentadiene anion and COT is the cyclooctatetraene dianion and Ln represents Dy(III), Ho(III), and Er(III); [2-3] (3) mononuclear dysprosium(III) complexes through hybrid of β-diketone and Cp’s derivatives; (4) CoIICoIII3 compounds with approximate D3 local symmetry. *This work was supported by the NSFC and the National Basic Research Program of China. [1] S.-D. Jiang, B.-W. Wang, G. Su, Z.-M. Wang, S. Gao, Angew. Chem. Int. Ed. 2010, 49, 7448-7451. [2] S.-D. Jiang, B.-W. Wang, H.-L. Sun, Z.-M. Wang, S. Gao, J. Am. Chem. Soc. 2011, 133, 4730-4733. [3] S.-D. Jiang, S.-S. Liu, L.-N. Zhou, B.-W. Wang, Z.-M. Wang, S. Gao, Inorg. Chem. 2012, 51, 3079-3087.

Keywords: single-molecule mononuclear complex

magnet,

uniaxial

anisotropy,

MS.A1.I3 Incorporation of Highly Anisotropic Ions into Coordination Clusters in the Search for Enhanced Single-Molecule Magnets Annie Powell,a Institute for Inorganic Chemistry, Karlsruhe Institute of Technology, Karlsruhe (Germany). E-mail: [email protected]

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The phenomenon of Single-Molecule Magnet (SMM) behaviour requires the correct combination of magnetic spin and anisotropy to be present within a molecular system. The coordination cluster, which has a core of metal ions held together by bridging ligands encapsulated within a shell of ligands, offers an ideal means to steer the necessary interplay of spin and anisotropy. For example, by combining high spin metal ions with highly anisotropic ions, such as those deriving from the 4f elements, it is possible to enhance the SMM characteristics.[1] [1] A. K. Powell, R. Sessoli, Coord. Chem. Rev, 2010, 253,2328-2341.

Keywords: Single-Molecule Magnet, Coordination Cluster, Lanthanides

MS.A1.C.01 Controlled Intramolecular Electron Transfers by External Stimuli Masayuki Nihei, Yoshihiro Sekine, Yuki Okamoto, Hiroki Oshio, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba (Japan). E-mail: [email protected] Cyanide-bridged multi-nuclear complexes have been known to exhibit interesting physical properties due to electronic and magnetic interactions between metal ions. Some cyanide-bridged mixed valence Fe-Co complexes have been currently reported to exhibit thermal and light-induced electron transfers between metal ions, called electron transfer coupled spin transitions (ETCSTs). The ETCST complexes exhibit a reversible conversion between a paramagnetic high-spin (HS) state ([FeII-CoIII]) and a diamagnetic low-spin (LS) state ([FeIIICoII]), and can be promising functional materials such as molecular switches. However, systematic control of the ETCST has been never established yet. We prepared a series of cyanide-bridged Fe-Co tetranuclear complexes [Co2Fe2(CN)6(L1)2(L2)4](PF6)2 (1: L1 and L2 are tri- and bi-dentate ligands) as well as hexanuclear complexes [Co2Fe4(CN)12(L1)4(L3)2] (2: L3 is meridional tridentate ligands). We present here 1) controls of ETCST by chemical modifications and external stimuli such as heat, protonation, and light irradiation, 2) thermal two-step ETCST behavior, and 3) light-switching between the paramagnetic state and a single-molecule magnet.[1]-[4] In X-ray structural analyses for 1, Fe and Co ions are alternately bridged by cyanide ions, forming macrocyclic tetranuclear cores. X-ray structural analyses and magnetic susceptibility data revealed that 1 exhibits a novel thermal two-step ETCST between paramagnetic HS, diamagnetic LS and intermediate (IM) states in the solid state. The X-ray diffraction study using synchrotron radiation revealed that the IM state exhibited long range ordering of HS and LS species with a checkerboad arrangement in the crystal lattice. In addition, 1 showed a thermal ETCST in solution, of which equilibrium temperatures were modulated by protonation to the terminal cyanide ions. The hexanuclear complex 2 has a extended core structure compoesed of a central square core and two additional mononuclear Fe units. 2 exhibited thermal one-step ETCST behavior between HT ([FeIIILS{CoIIHS2FeIIILS2}FeIIILS]) and LT ([FeIIILS{CoIIILS2FeIILS2}FeIIILS]) phases. The light-irradiation to the LT phase induced significant increase of magnetic moment, which is due to the light-induced conversion from the paramagnetic LT phase to the ferromagnetic HT phase. Ac magnetic susceptibility measurements at very low temperature revealed that the light-induced HT phase showed slow magnetic relaxation characteristic of single-molecule magnet. As a result, 2 is the first photo-switchable single-molecule magnet. [1] M. Nihei, Y. Sekine, N. Suganami, K. Nakazawa, A. Nakao, H. Nakao, Y. Murakami, H. Oshio, J. Am. Chem. Soc., 2011, 133, 3592. [2] G. N. Newton, M. Nihei, H. Oshio, Eur. J. Inorg. Chem. 2011, 3031. [3] M. Nihei, Y. Sekine, N. Suganami, H. Oshio, Chem. Lett. 2010, 39, 978. [4] M. Nihei, Y. Okamoto,

Microsymposia

Keywords: electron-transfer, spin-transition, single-molecule magnet

MS.A1.C.02 A Triply Switchable (T, P and Redox) Cobalt Complex: Abrupt, Complete, Reversible and Hysteretic Spin Crossover Sally Brooker,a,* Matthew G. Cowan,a Juan Olguín,a Suresh Narayanaswamy,b Jeffery L. Tallonb, aDepartment of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology, University of Otago, PO Box 56, Dunedin 9054, New Zealand. b MacDiarmid Institute for Advanced Materials and Nanotechnology and Industrial Research Limited, PO Box 31310, Lower Hutt, New Zealand. E-mail: [email protected] Few examples of cobalt(II) complexes displaying thermally induced complete, abrupt and hysteretic or pressure induced spin crossover have been reported.[1-3] As part of our continued interest in imide complexes,[4] which has produced the first isolated cobalt(II) complex of an imide ligand, we present here the new, triply switchable, complex [CoII(dpzca)2].5 Detailed structural analysis of both spin states, as well as variable temperature magnetic, variable pressure Raman, and redox properties of this complex, will be reported and discussed.

[1] S. Hayami, Y. Komatsu, T. Shimizu, H. Kamihata, Y. Hoon Lee, Coord. Chem Rev. 2011, 255, 1981. [2] H. A. Goodwin, Top. Curr. Chem. 2004, 234, 23. [3]Gradual incomplete dicobalt(II) SCO: S. Brooker, P.G. Plieger, B. Moubaraki, K.S. Murray, 1999, 38, 408, and cover. [4] R.M. Hellyer, D.S. Larsen and S. Brooker, Eur. J. Inorg. Chem., 2009, 1162; M. G. Cowan, S. Brooker, Dalton Trans., 2012, 41, 1465-1474, and cover. [5] M. G. Cowan, J. Olguín, S. Narayanaswamy, J. L. Tallon, S. Brooker, J. Am Chem. Soc. 2012, 134, 2892, and cover.

MS.A1.C.03 Magnetism and chirality in [M(CN)8]-bridged clusters and extended networks Robert Podgajny,a Szymon Chorążya, Wojciech Nitek,a Anna. M. Majcher,b Edward Gorlich,b Michał Rams,b Tomasz Fic,b Zbigniew Tomkowiczb and Barbara Sieklucka,a aFaculty of Chemistry, Jagiellonian University, Kraków, (Poland). bInstitute of Physics, Jagiellonian University, Kraków, (Poland). E-mail: podgajny@ chemia.uj.edu.pl The progress in the field of data storage and processing requires the development of synthetic strategies towards novel multifunctional materials. A promising route to reach the goal is approach between magnetism and chirality, as it was shown that a combination of these functions may lead to the strong enhancement of the magneto-chiral dichroism in magnetically ordered phase compared with that of the paramagnetic one.[1-3] Several synthetic strategies have been established to give the enantiopure magnetic materials.[4] In this contribution we developed the route consisting in the use of enantiopure molecular precursors. Combining the R- or S-α-methyl-2-pyridinemethanol (R-mpm and S-mpm) with MAn+ (MA=Mn, Co) and [W(CN)8]3- (5d1) or [NbIV(CN)8]4(4d1) in different media we obtained discrete pentanuclear or pentadecanuclear cyano-bridged clusters as well as the extended networks. Chirality of synthesized enantiopure phases is localized on sp3 carbon centre of mpm ligand as well as on cis-[MA(μ-NC)2(R/Smpm)2] moieties. The examples of magnetically ordered networks will be also presented as the candidates to observe the magneto-chiral effects.

[1] K. Inoue, K. Kikuchi, M. Ohba, H. Okawa., Angew. Chem. Int. Ed., 2003, 42, 4810 –4813. [2] C. Train, R. Gheorghe, V. Krstic, L.-M. Chamoreau, N. S. Ovanesyan, G. L. J. A. Rikken, M. Gruselle, M. Verdaguer, Nature Mater. 2008, 7, 729-734. [3] J. M. Bradley, A. J. Thomson, R. Inglis, C. J. Milios, E. K. Brechin, S. Piligkos, Dalton Trans. 2010, 39, 9904–9911. [4] C. Train, M. Gruselle, M. Verdaguer, Chem. Soc. Rev., 2011, 40, 3297–3312.

Keywords: Magnetism, Chirality, Cyanido-bridges

Keywords: spin crossover, cobalt(II), imide

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Y. Sekine, N. Hoshino, T. Shiga, P.-C. Liu, H. Oshio, Angew. Chem. Int. Ed., accepted (DOI: 10.1002/anie.201202225).

Microsymposia MS.A1.C.04 Hybrid Spin-Crossover/Luminescence Silica Nanoparticles Juan Manuel Herrera,a Silvia Titos Padilla,a Enrique Colacio,a a Department of Inorganic Chemistry, Faculty of Sciences, University of Granada (Spain). E-mail: [email protected] Molecular Magnetism is a constantly developing field in which, amongst others, much efforts are currently devoted to both, i) the preparation of nanostructured materials based on spin crossover (SCO) complexes and ii) the design of new molecular systems that combine spin crossover and other interesting properties such as luminescence.[1] Our group has recently developed an original strategy to prepare bifunctional SCO/luminescence nanoparticles which consists of using silica nanoparticles (SiO2NPs) as a matrix for the SCO component. [2] Indeed, silica is a particularly suitable material for the preparation of SiO2NPs@SCO systems because its high porosity allows for the incorporation of SCO compounds. As silica does not absorb light and does not interfere with magnetic fields, the SCO compounds will keep their original optical and magnetic properties. Additionally, luminescence species conveniently functionalized with alcoxysilane groups can be graphted to the surface of these SiO2NPs@SCO, leading to the obtention of bifunctional core-SCO/shell-Luminescence nanoparticles. Thus, we have prepared hybrid SiO2NPs containing a SCOcore based on the [Fe(Trz)3](BF4) family of complexes (HTrz = 1,2,4-1H-Triazole) and a luminescence shell. These nanomaterials exhibit a thermally induced Low Spin → High Spin transition which is accompanied by a drastic colour change. This optical bistability tunes the luminescence properties of the fluorophores graphted to the surface. The synthetic approach, and the structural, photophysical and magnetic properties of these new nanomaterials will be discussed in detail in this communication. [1] a) I. Boldog et al., Angew. Chem. Int. Ed. 2008, 47, 6433-6437; b) J. R. Galán-Mascarós et al., Inorg. Chem. 2010, 49, 5706-5714; c) F. Volatron et al., Inorg. Chem. 2008, 47, 6584-6586; d) H. Matsukizono et al., Chem. Lett., 2008, 37, 446-447; e) M. Matsuda, et al., Chem. Lett., 2008, 37, 374-375. [2] S. TitosPadilla et al., Angew. Chem. Int. Ed. 2011, 50, 3290-3293.

Keywords: Spin-crossover, luminescence, silica nanoparticles

MS.A1.C.05 Polycyano-Based Spin Crossover Systems: Strategy and Design Smail Triki,a Fatima Sétifi,a,b Eric Milin,a Franck Thétiot,a Véronique Patinec,a Carlos J. Gómez-García,c a Université de Brest-UMR CNRS 6521, 6 Av. V. Le Gorgeu, 29238, Brest France. (b) Département de Chimie, Université Ferhat Abbas, Sétif, Algeria. cInstituto de Ciencia Molecular, Universidad de Valencia, 46980 Paterna, Valencia, Spain. E-mail: [email protected] Spin crossover (SCO) materials are one of the best representative examples of molecular switchable materials. The goal nowadays is to design SCO materials with perfectly controlled magnetic and photomagnetic behaviours in a rational chemical synthetic strategy. Up to now, numerous SCO materials have been synthesized and described in the literature, but it has never been investigated the potential impact of using anionic organic ligands, connecting the active metal centers, on the switching properties (hysteresis width, abruptness of the transition,…). In this context, our group is interested in the design of new series of SCO compounds using polynitrile anions as ligands [1]. The use of such anionic ligands in combination with neutral appropriate co-ligands is a very promising and appealing strategy for obtaining

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molecular architectures with different topologies and dimensionalities thanks to their ability to coordinate and bridge metal ions in many different ways. The presence of several potentially coordinating CN groups, their rigidity and their electronic delocalization allows the synthesis of original high dimensional coordination polymers exhibiting original magnetic transitions such as spin-Peierls-like transition [2] or SCO behaviour [1]. Here we report an overview of the results based on some of these polycyano ligands, showing their rich coordination chemistry and their crucial role in the design of molecular materials exhibiting unusual magnetic behaviours. [1] (a) C. Atmani, F. El Hajja, S. Benmansour, M. Marchivie, S. Triki, F. Conan, V. Patinec, H. Handel, G. Dupouy, C. J. Gómez-García Coord. Chem. Rev. 2010, 254, 1559-1569; (b) G. Dupouy, M. Marchivie, S. Triki, J. Sala-Pala, J.-Y. Salaün, C. J. Gómez-García, P. Guionneau, Inorg. Chem., 2008, 47, 89218931. (c) G. Dupouy, M. Marchivie, S. Triki, J. Sala-Pala, C. J. Gomez-Garcia, S. Pillet, C. Lecomte, J.-F. Létard, Chem. Commun., 2009, 3404–3406 ; (d) G. Dupouy, S. Triki, M. Marchivie, N. Cosquer, C. J. Gómez-García, S. Pillet, E.-E. Bendeif, C. Lecomte, S. Asthana, J.-F. Létard, Inorg. Chem. 2010, 49, 9358-9368. [2] F. Setifi, S. Benmansour, M. Marchivie, G. Dupouy, S. Triki, J. Sala-Pala, J.-Y. Salaün, C. J. Gómez-García, S. Pillet, C. Lecomte, E. Ruiz, Inorg. Chem. 2009, 48, 1269–1271.

Keywords: Ligands, Switchable materials, Magnetic bistability

MS.A1.C.06 Lanthanoid Alkoxide & Thiolate Clusters: Synthesis, Structure & Magnetism Robin J. Blagg, Floriana Tuna, Eric J.L. McInnes & Richard E.P. Winpenny, School of Chemistry & Photon Science Institute, University of Manchester, Oxford Road, Manchester, M13 9PL, U.K. E-mail: [email protected] As part of our studies into the magnetic properties of 4f-coordination complexes, we’ve targeted a range of highly symmetric lanthanoid alkoxide and lanthanoid thiolate clusters using various synthetic routes and investigated their magnetic properties. These include, a series of C4v symmetric square-based pyramidal oxo-centred pentalanthanoid clusters, [Ln5(µ5-O) (µ3-OiPr)4(µ2-OiPr)4(OiPr)5]. We have shown that both the dysprosium [1] and holmium [2] pyramids act as single molecule magnets (SMMs) at temperatures as high as 40 and 33 K respectively, with thermal energy barriers to relaxation of 367 and 278 cm–1 respectively. These are the highest observed for any poly-metallic SMM. A second series, are a range of octalanthanoid cubes, [Ln8(µ4-S)6(µ2SPh)12L8], which have an Oh symmetric {Ln8} core, and are currently under investigation to determine their magnetic properties. Other clusters including those of the general form ‘Ln(OtBu)3’, ‘Ln(OEt)3’ and ‘Ln(SPh)3’, which demonstrate various structural archetypes and hence magnetic properties may also be discussed. [1] R.J. Blagg, C.A. Muryn, E.J.L. McInnes, F. Tuna & R.E.P. Winpenny,

Microsymposia Angew. Chem. Int. Ed., 2011, 50, 6530-6533. [2] R.J. Blagg, F. Tuna, E.J.L. McInnes & R.E.P. Winpenny, Chem. Commun., 2011, 47, 10587-10589.

Keywords: Lanthanoids, Magnetism, Clusters

[1] R. Sessoli, A. K. Powell, Coord. Chem. Rev. 2009, 253, 2328-2341. [2] M. Evangelisti, E. K. Brechin, Dalton Trans., 2010, 39. 4672-4676. [3] K. S. Pedersen, J. Bendix et al., Chem. Sci. 2012, 3, 1024-1032. [4] T. Birk, K. S. Pedersen, J. Bendix et al. Inorg. Chem., 2012, DOI: 10.1021/ic300421x.

Keywords: Molecular magnetism, fluoride, magnetic cooling

MS.A1.C.07

Interest in molecular clusters incorporating lanthanide ions has been boosted by the quest for magnetically anisotropic molecular systems as single-molecule magnets[1] and, more recently, the increasing focus on nanoscopic coolers[2] has established a need for molecular entities exhibiting very large spin ground states. Assembly of polynuclear lanthanide complexes employing kinetically robust chromium(III)-fluorido complexes has proven a convenient route to small heterometallic 3d-4f clusters with fluoride as bridging ligands. By this approach the first examples of unsupported fluoride bridges between a paramagnetic transition metal and a lanthanide ion have been synthesized. Thus, reactions of simple lanthanide compounds with various Cr(III)-fluorido complexes yield extensive series of polynuclear, fluoride-bridged 3d–4f clusters in which the cluster topology is directed by the structure of the Cr(III) precursor giving for instance molecular rods, squares or pyramids.[3,4] The propensity of fluoride for linear bridging also aids in bringing topological control into the synthesis of 3d-4f clusters. The resulting, structurally simple, systems have allowed for modeling of the magnetic properties and for the first quantification of magnetic coupling between 3d and 4f centers across a fluoride bridge, for orbitally degenerate as well as for orbitally non-degenerate 4f systems.

MS.A1.C.08 Photomagnetism: from the Prussian Blue Analogues to their molecular models Rodrigue Lescouëzec,a Abhishake Mondal,a Alexandrine Flambard,a Yanling Li,a Mannan Seuleiman,a Marylise Buron,b Loïc Toupet,b Miguel Julve,c aInstitut Parisien de Chimie Moléculaire, UPMCParis6, Paris, (France). bInstitut de Physique de Rennes, Université Rennes2, Rennes (France). cUniversity of Valencia, Institute for Molecular Science, Valencia, (Spain). E-mail: rodrigue.lescouezec@ upmc.fr The Prussian Blue Analogues (PBAs), AxM’y[M(CN)6]z, (A = alkaline cation; M and M’ = transition metal ions) are well-known inorganic polymers whose magnetic properties can be finely tuned by varying the nature of the metal ions. For example, the Fe-Co derivatives can exhibit interesting photomagnetic behaviour [1]. However, these physical properties are strongly dependent on the stoichiometry of the PBA. Indeed, we have shown by using (paramagnetic)NMR spectroscopy that the local structure of these materials is highly sophisticated, many metal ion surroundings coexisting in the material [2]. The rationalization of their physical properties is therefore made difficult and the photomagnetism arises from different Fe-Co pairs. The design of discrete Fe-Co molecular models offers an alternative route for a better understanding of the photomagnetic effects. By studying a family of Fe-Co molecular squares, we have shown that photomagnetism depends on both structural and electronic parameters [3]. Interestingly, we have also evidenced an on/off (para ⇔ dia) photo-switchable effect, the Fe-Co squares behaving as effective molecular switches.

[1] O. Sato, T. Iyoda, A. Fujishima, K. Hashimoto, K. Science, 1996, 272, 704. [2] (a) A. Flambard, F.H. Köhler, R. Lescouëzec, Angew Chem. Int. Ed., 2009, 48, 1673; (b) A. Flambard, F.H. Köehler, R. Lescouëzec, B. Revel, Chem. Eur. J., 2011, 17, 11567. [3] (a) J. Mercurol, Y. Li, E. Pardo, O. Risset, M. Seuleiman, H. Rousselière, R. Lescouëzec, M. Julve, Chem. Commun., 2010, 46, 8995; (b) E. Pardo, M. Verdaguer, P. Herson, H. Rousselière, J. Cano, M. Julve, F. Lloret, R. Lescouëzec, Inorg. Chem. 2011, 50, 6250.

Keywords: (photo)magnetism, molecular materials, molecular switches

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Employing Fluoride Bridging as a Synthetic Strategy for New Types of Polynuclear Magnetic Systems Jesper Bendix,a Kasper Steen Pedersen,a Torben Birk,a Stergios Piligkos,a Högni Weihe,a Christian Aagaard Thuesen,a Magnus SchauMagnussen,a Jan Dreiser,b Marco Evangelisti,c Suarab Singh,d Gopalan Rajaraman,d aDepartment of Chemistry, University of Copenhagen, (Denmark). bSwiss Light Source, Paul Scherrer Institut, (Switzerland). c University of Zaragoza (Spain). dIndian Institute of Technology Bombay(India). E-mail: [email protected]

Microsymposia MS.A1.C.09

MS.A1.C.10

Highly Selective Dual Molecular Sensing in a Luminescent Nanoporous Magnet Emilio Pardo,a Jesús Ferrando-Soria,a Thais Grancha,a Miguel Julve,a Francesc Lloret,a Yves Journaux,b Jorge Pasán,c Catalina Ruiz-Pérez,c Hossein Khajavi,d Pablo Serra-Crespo,d Jorge Gascond and Freek Kapteijn,d aInstitut de Ciència Molecular (ICMol), Universitat de València, E–46980 Paterna, Valencia, Spain. bInstitut Parisien de Chimie Moléculaire, Université Pierre et Marie Curie-Paris 6, UMR 7201, F–75005 Paris, France. c Laboratorio de Rayos X y Materiales Moleculares, Departamento de Física Fundamental II, Universidad de La Laguna, E–38201 Tenerife, Spain. dCatalysis Engineering-Chemical Engineering Dept, Delft University of Technology, Julianalaan 136, 2628 BL Delft. E-mail: [email protected]

A Mononuclear Fe(III) Single Molecule Magnet with a 3/2 to 5/2 Spin Crossover Susanne Mossin,a Ba Tran,b Debashis Adhikari,b Maren Pink,b Jörg Sutter,c Frank Heinemann,c Karsten Meyer,c Daniel J. Mindiola,b aDTU Chemistry, Technical University of Denmark, Lyngby, (Denmark). b Department of Chemistry, Indiana University, Bloomington, Indiana (USA). Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Erlangen (Germany) E-mail: [email protected]

The coexistence of different functionalities in the so-called metalorganic frameworks (MOFs) in large part due to their unique porous structures has enabled them to become a very promising new type of sensing materials. Among the variety of multifunctional MOFs, those exhibiting luminescent properties attract special interest because of the sensitivity of this property to the structural characteristics of the MOF, allowing the obtention of luminescent sensing MOFs. Here we show a novel metal-organic framework (MOF) of formula MV[Mn2Cu3(mpba)3(H2O)3] . 20H2O (H2O@1) [MV2+ = methylviologen and mpba = N,N’-1,3-phenylenebis(oxamate)] which has been rationally synthesized by using the complex-as-ligand strategy. H2O@1 possesses an anionic oxamato-based MnII2CuII3 double layer structure hosting a large amount of water molecules and MV2+ countercations as guests. The combination of highly ordered MV2+ moieties within a shape selective scaffold and a long range ferromagnetic ordering of the oxamato-bridged mixed-metal network in 1 results in very selective non-linear fluorescence and magnetic properties. Thus, because of the solvent- and gas-sorption-induced optical and magnetic switching behaviour, H2O@1 holds a large application potential for sensing of small molecules like H2O, MeOH or CO2.

Keywords: Multifunctional materials, magnetism, luminescence

The single centered iron(III) complex [(PNP)FeCl2], PNP = N[2-P(CHMe2)2-4-methylphenyl]2–) synthesized from [(PNP)FeCl] [1] exhibits slow relaxation of the magnetization in zero applied field at low temperature. This is evidenced by the out-of-phase ac susceptibility data (10 to 1000 Hz) and the Arrhenius plot presented in the figure below as well as a six-line Mössbauer spectrum. In this frequency range the Arrhenius plot is almost perfectly linear unlike other single center single molecule magnets.[2] At low temperature the dc susceptibility data and the intensity of the EPR lines is well fitted by an axial spin Hamiltonian for the intermediate spin state (S = 3/2). The zero field splitting parameter, D, found in the fit with this model is only -11 cm-1 which provides a calculated spin reversal barrier of 22 cm-1. The experimentally obtained barrier from the ac susceptibility is 34 cm-1 and is thus actually larger than the calculated from the spin Hamiltonian model. At temperatures around 80 K a gradual spin transition to the high spin state sets in but is still not complete at 300 K. The spin transition has been investigated by Squid magnetometry, X-ray diffraction, Mössbauer and EPR spectroscopy. The gradual spin transition is observed by all spectroscopies and closely follows the temperature dependence of the structural parameters. The structural change can be described as the PNP pincer ligand closing at low temperatures resulting in an increased sigma donation into the d(z2) orbital which is then depopulated leading to the intermediate spin state. The different spectroscopic evidence leading to the conclusions we have drawn on this novel coordination compound will be presented. There will also be a discussion of the importance of quantum mechanically admixed spin states and “bad quantum numbers” on the high value of the spin reversal barrier and the suppression of the quantum tunnelling of the magnetisation at low temperature.

[1] Adhikari, D.; Basuli, F.; Fan, H.; Huffman, J. C.; Pink, M.; Mindiola, D. J. Inorg. Chem. 2008, 47, 4439. [2] Zadrozny, J. M.; Long, J. R. Am. Chem. Soc. 2011, 133, 20732.

Keywords: iron, SMM, spin transition

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Microsymposia MS.A1.C.11 Photoswitchable Nanoparticles of Spin-Crossover Iron Complexes Antoine Tissot,a,b Pradip Chakraborty,a Marie-Laure Boillot,b Andreas Hauser,a aPhysical Chemistry Department, University of Geneva, Geneva, (Switzerland). bICMMO, Inorganic Chemistry Group, University of Paris Sud, Orsay (France). E-mail: antoine.tissot@ unige.ch

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Spin-crossover molecular materials are prototypes for photoactive and bistable solids, and thus their switching properties stimulate a lot of interest for fundamental and applicative goals, such as molecular switches and information storage. Precise control of their spin-state may be achieved by wavelength selective irradiation via the LightInduced Excited Spin State Trapping (LIESST) effect [1]. Quantitative photoswitching of iron complexes, often intensely coloured, requires their processing into materials with optimized optical properties. Our aim is to elaborate switchable nano-objects, particularly by focusing on the effect of size reduction on the photo-switching dynamics. Within the past few years, a lot of work has been dedicated to the synthesis of spin-crossover coordination-polymer-based nanoparticles [2]. This was mainly focused on the effect of the size reduction on cooperativity during the thermal spin transition. Here, we present new synthetic methods, based on fast precipitation and/or confinement within a polymeric matrix that lead to the formation of nano-objects with 0D spin-crossover complexes. This strategy allows us to study size reduction effects with a large number of compounds, some of them being known to present the above-mentioned LIESST effect. With the [FeIII(3-OMeSalEen)2]PF6 spin-crossover complex, [3] nanoparticles have been prepared combining fast precipitation and confinement within an organic polymer. A detailed study of the effect of size on the switching properties will be presented [4]. Moreover, these particles, processed as a thin film, have been used to probe the Low-Spin ® High-Spin photo-conversion dynamics using ultrafast optical spectroscopy [5]. The spin-crossover prototype [FeII(6-mepy)3tren](PF6)2, has also been used to prepare size-controlled amorphous in-silica nanoparticles [6] as well as crystalline nano-objects. Detailed photophysical studies of these particles show intriguing effects of crystallinity on the photoinduced spin relaxation behaviour. [1] A. Hauser, Top. Curr. Chem. 2004, 234, 155-198. [2] A. Bousseksou, G. Molnár, L. Salmon, W. Nicolazzi, Chem. Soc. Rev., 2011, 40, 3313-3335. [3] A. Tissot, R. Bertoni, E. Collet, L. Toupet, M.-L. Boillot. J. Mater. Chem., 2011, 21, 18347-18353. [4] A. Tissot, L. Rechignat, A. Bousseksou, M.-L. Boillot. J. Mater. Chem., 2012, 22, 3411-3419. [5] R. Bertoni, M. Lorenc, A. Tissot, M. Servol, M.-L. Boillot, E. Collet, submitted to Angew. Chem. Int. Ed. [6] A. Tissot, J-F. Bardeau, E. Rivière, F. Brisset, M.-L. Boillot. Dalton Trans., 2010, 39. 7806-7812.

Keywords: spin crossover, nanoparticles, LIESST

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MS.A2.KN1 Interfacing Nanocarbons with Coordination Compounds for Solar Energy Conversion Schemes Dirk M. Guldi,a aDepartment of Chemistry and Pharmacy, University of Erlangen, Erlangen, (Germany). E-mail: [email protected] There is no doubt, the outstanding optical and electronic properties that low-dimensional nanocarbons exhibit call for their implementation into optoelectronic devices. To harvest their enormous potential it is, however, essential to probe them in multifunctional electron donor-acceptor systems, especially the interactions between electron donors/electron acceptors and nanocarbons. This presentation outlines challenges and recent breakthroughs in the area of interfacing inorganic coordination compounds with low-dimensional nanocarbons. In the context of coordination compounds, I will focus on macrocyclic complexes of metal ions, organometallic compounds, and on polyoxometalates. On the contrary, the low-dimensional nanocarbons range from fullerenes (0D) and carbon nanotubes (1D) to graphene (2D). Particular emphasis is placed on designing and probing solar energy conversion nanohybrids. Keywords: nanocarbon, coordination compounds, solar energy conversion

MS.A2.KN2 Nanoparticulate Water Oxidation Catalysts Derived from Molecular Precursors Leone Spiccia, School of Chemistry and Australian Centre of Excellence for Electromaterials Science, Monash University, Victoria, 3800, Australia. Email: [email protected] Hydrogen from solar water splitting has the potential to provide an abundant, renewable and cheap source of energy. Photo-electrochemical devices, which either use sunlight directly to split water or alternatively generate electrical energy to power water splitting, have been identified as a highly promising technology and are under intense investigation. These devices couple two key electrochemical processes: (1) water oxidation at the anode, 2H2O ⇌ O2 + 4H+ + 4e-; and (2) hydrogen ion reduction at the cathode, 2 H+ + 2e- ⇌ H2. Although significant advances have been made, many challenges still need to be addressed before solar hydrogen production will become a commercial reality. In particular, catalysts capable of efficiently catalysing the complex and energetically demanding oxygen-evolving half reaction are urgently required. Drawing inspiration from the only known catalytic core to oxidise water in vivo - the Mn4Ca1Ox cluster in the Water Oxidizing Centre of Photosystem II (PSII) - our research has been focussing on water oxidation catalysts derived from earth abundant elements.1 Our initial studies explored the application of bio-inspired tetranuclear manganese clusters. Robust photoanodes were developed by imbedding such clusters into Nafion films deposited on various electrodes, which efficiently catalysed water oxidation in vitro on illumination with visible light and application of a potential bias.[1] We also demonstrated that these photoanodes could be combined with a sensitiser into a photo-electrochemical cell which, like PSII, oxidizes water using only visible light as energy source.[2] This multilayer device was based on the dye sensitized solar cell and consists of a RuIIdye sensitiser adsorbed on a titania semiconductor film on which was coated a Nafion film containing the manganese catalyst. Detailed investigations of the fate of the Mn cluster during catalysis were subsequently carried out using X-ray Absorption Spectroscopy (XAS) and high resolution Transmission Electron

Microscopy (TEM). The Mn4 precursor was found to dissociate in the Nafion films forming Mn2+ species which, on application of a bias, are oxidized to nanoparticles of a disordered MnOx phase (detected via TEM) that undergoes reduction and releases oxygen on illumination. [3] Thus, water oxidation catalysis involves cycling between the photoreduced MnII product and the oxide, and not the original cluster. The operation of these photoanodes has parallels in Mn biogeochemistry, where oxidative processes form solid MnIII/IV oxides, which in sunlight undergo photoreduction to Mn2+. Intrigued by this transformation, EPR studies were carried out which confirmed the catalytic cycle proposed on the basis of the XAS experiments. Given that catalysis does not involve the original cluster, it would have been anticipated that catalytic activity would not be dependent on the Mn precursor. To our surprise, however, an examination of a series of Mn clusters found the contrary. Not only did the size and crystallinity of the nanoparticles generated from the various precursors vary, so did their catalytic activity. [1] R. Brimblecombe, et al. Angew. Chem. Int. Ed. Engl., 2008, 47, 7335-7338. [2] R. Brimblecombe, et.al, J. Am. Chem. Soc., 2010, 132, 2892–2894. [3] R. K. Hocking, et al., Nature Chem., 2011, 3, 461-466.

Keywords: water oxidation, manganese oxides, catalysis

MS.A2.I1 Shaping the Beating Heart of Artificial Photosynthesis: Oxygenic Nano-Hybrid Interfaces Marcella Bonchio,a aCNR-Institute for Membrane Technology, Chemical Sciences Dpt, University of Padova, Padova, (Italy). E-mail: [email protected] Water is a green carrier of electrons stored in very stable chemical bonds, readily available in many forms and distributed in vast geographic areas. Therefore, water oxidation, meaning the stepwise abstraction of four electrons from its O-H bonds, releases oxygen as direct product, but in doing this, provides the necessary reduction equivalents to address the dream goals of energy research i.e. H2 generation and CO2 abatement. In this scenario, the oxidation of water performed with low activation energy, under multi-turnover catalytic conditions, is pivotal for regenerative atmosphere, green-house gas remediation, and carbon-neutral renewable fuels. [1] A major research effort is therefore dedicated to address the artificial transposition of what is conceived as the bottle-neck of Natural Photosynthesis. Success in this task primarily depends on the interplay of light-activated multi-electron oxidation and reduction cycles and on the invention of stable and robust water oxidation catalysts, liberating oxygen with fast rates, high quantum yield, and long-term activity. A promising perspective is herein envisaged in the molecular design of functional metal-oxide cores and hybrid nano-materials. [2] A recently discovered pathway is carved within the class of inorganic metal-oxide clusters displaying a unique mimicry of the catalytic core within the membrane bound Photosystem II (PSII) enzyme. Furthermore, the shaping of their functions at the interface of specifically tailored carbon nano-structures and/or polymeric scaffolds opens a vast scenario for tuning electron/proton transfer in term of rates, distance, geometries and communication between donor/acceptor centers. Innovation is envisaged based on the molecular modification of the hybrid photo-catalytic center and of its environment. [3]

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Microsymposia

[1] A. Sartorel, M. Carraro, F.M. Toma, M. Prato, M. Bonchio, En. Env. Sci. 2012, 5, 5592. [2] M. Bonchio et al., Nature Chem., 2010, 2, 826–831; ChemSusChem, 2011, 4, 1447–1451. [3] F. Puntoriero, A. Sartorel, M. Orlandi, G. La Ganga, S. Serroni, M. Bonchio, F. Scandola and S. Campagna, Coord. Chem. Rev., 2011, 255, 2594–2601.

Keywords: multi-electron catalysis, artificial photosynthesis, carbon nanostructures

MS.A2.I2 Molecular Control of Interfacial Electron Transfer in DyeSensitized Solar Cells Neil Robertson,a Nina Chadwick,a Tracy E. Hewat, Miquel Planells, a School of Chemistry and EaStCHEM, University of Edinburgh, King’s Buildings, Edinburgh EH9 3JJ, UK. E-mail: [email protected] Dye-sensitised solar cells convert solar energy into electrical energy via photoexcitation of dye molecules bound to a wide bandgap semiconductor such as TiO2. Following photo-induced electron transfer from the dye to TiO2, the dye is regenerated by electron transfer from a redox electrolyte or solid-state hole transport material (HTM). The power-conversion efficiency is greatly dependent on the electron transfer processes occurring at the TiO2-dye-HTM interface, which can be controlled through the structure of the dye or other surface binding molecules. We will present results to illustrate the consequences of modification of Ru dyes and other surface-binding molecules on the interactions at the interface and consequent electron transfer processes. In particular, some common features of Ru dyes are often incorporated without detailed investigation of these aspects. These include the 4,4’-dicarboxy-bipyridine ligand used as a binding unit to TiO2 and the NCS co-ligand which is believed to play an important role in dye-electrolyte interactions as well as affecting the dye stability. Accordingly we have modified and probed these common dye features and will discuss the consequences on cell efficiency and stability. Keywords: dye-sensitized, ruthenium, solid-state

MS.A2.I3 Anchoring Water Oxidation Catalysts: Towards a Water Splitting Photochemical Device Xavier Sala,a Lluís Escriche,a Jordi García-Antón,a Roger Bofilla and Antoni Llobet,a,b. aDepartament de Química, Universitat Autònoma de Barcelona, Bellaterra (Barcelona, Spain) bInstitut Català d’Investigació Química (ICIQ, Tarragona, Spain). E-mail: xavier. [email protected] Oxygen-Oxygen bond formation is the key step for the oxidation of water to molecular oxygen: a reaction of interest from a biological perspective and also for establishing new energy conversion schemes.

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A few Ru complexes have been described recently that are capable of catalyzing the water oxidation reaction, and their performance has been shown to be strongly dependent on, nuclearity, oxidation state and ligand topology.[1] A step forward in the field consists on unraveling the different reaction pathways trough that these reactions proceed. We have tackled this challenging topic by carrying out thorough electrochemical, spectroscopic and kinetic analysis together with O-18 labeling studies and DFT calculations. The combination of all these results gives evidence for mechanisms involving: intramolecular O-O bond formation, water nucleophilic attack and bimolecular O-O bond formation.[2] The anchoring of these catalysts into conducting solid supports is therefore the next mandatory step to demonstrate the feasibility of building a solid-state device for water oxidation that could be integrated into a larger device for the photo-production of H2. Polypyrrolic electro-polymerization onto vitreous carbon sponges (VCS) and fluorine-doped tin oxide (FTO), and anchoring onto rutile TiO2 or FTO-TiO2 surfaces have been the explored strategies. The catalytic performance of these new heterogeneous water oxidation systems will also be discussed.[3] [1] (a) X. Sala; M. Rodriguez; I. Romero; L. Escriche; A. Llobet, Angew. Chem. Int. Ed. 2009, 48, 2842. [2] (a) S. Romain; F. Bozoglian; X. Sala, X; A. Llobet, J. Am. Chem. Soc. 2009, 131, .2768. (B) X. Sala; E. Z. Ertem; C. J. Cramer; L. Gagliardi, A. Llobet. et al. Angew. Chem. Int. Ed. 2010, 49, 7745-7747. (c) J. Mola,; C. Dinoi; X. Sala; I. Romero; M. Rodríguez; A. Llobet Dalton Trans. 2011, 40, 3640. [3] (a) J. Mola; E. Mas-Marzà; X. Sala; I. Romero; M. Rodríguez; C. Viñas; T. Parella; A. Llobet, Angew. Chem. Int. Ed. 2008, 47, 5830-5832. (b) L. Francàs. X. Sala; J. Benet-Buchholz; L. Escriche; A. Llobet, ChemSusChem 2009, 2, 321-228. (c) L. Francàs; X. Sala, X. Fontrodona, L. Escriche; A. Llobet Inorg. Chem. 2011, 50, 2771-2781.

Keywords: water oxidation, hydrogen, fuel cells

MS.A2.C.01 Solid-State Protonics in Coordination Chemistry Hiroshi Kitagawa, Division of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan). E-mail: [email protected] Solid-state protonics is a new research field attracting much current attention. One of the most urgent subjects in this field is to create a novel proton conductor, from the viewpoint of developing new energy and energy conservation technologies, including photovoltaic, hydrogen storage and fuel cell technologies. In this work, we report on a proton-conductive organic-inorganic hybrid system, which is a coordination polymer. Such a metal-dimer system with multi-redox property has a large potentiality for the creation of new-functional and high-performance materials in metal-complex solids [1]. We have developed several kinds of proton conductors, which are 0-D, 1-D, 2-D and 3-D coordination polymers. From the complex-plane impedance measurements, all the coordination polymers were found to be highly proton-conductive at room temperature. Among them, H2dtoaCu exhibits highest proton conduction (~10-2 S cm-1). This value is comparable to that of Nafion, which is famous for a solid electrolyte of fuel cell. The mechanism of proton conduction is discussed in detail. New highly proton-conductive coordination materials, conductive mixed-valent nanotube-MOF (Figure) and highly- concentrated hydrogen-storage nano-materials are also presented.

Microsymposia MS.A2.C.03

[1] Kitagawa, H. et al., J. Am. Chem. Soc., 2011, 133, 5640-5643, J. Am. Chem. Soc., 2011, 133, 2034-2036, Nature Materials, 2011, 10, 291-295, Nature Materials, 2008, 7, 41-51, Nature Materials, 2009, 8, 476, Nature Chemistry, 2009, 1, 689, Nature Materials, 2010, 9, 565-571.

Keywords: Protonics, Proton conductor, MOF

MS.A2.C.02 Light-driven H2 Evolution of Non-precious Metal Complexes with Multifunctional Ligands Takeshi Matsumoto,a Syo Ueno,b Masanori Wakizaka,b Hirokazu Yano,b Atsushi Kobayashi,b Ho-Chol Chang,b and Masako Kato,a,b a Center of Strategic Utilization of Elements, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan). b Department of Chemistry, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan). E-mail: [email protected] Hydrogen is an attractive clean fuel candidate for renewable energy storage and transport. On this point of view, well-defined molecular catalysts, particularly utilizing earth-abundant elements, provide a fascinating approach toward H2 production. Artificial H2 production reactions have been studied for more than three decades using molecular based systems containing a photosensitizer and a catalyst. [1] However, frequent use of precious elements limits their wide applications. Under such circumstances, we have been actively engaged on creation of precious-metal-free photochemical H2 production systems, as an issue in the “Gensosenryaku Project”, which is aiming at developing alternative high performance materials superior to the state-of-theart materials without using rare and harmful elements.[2] On this standpoint, utilization of non-precious metal-based complexes are one of the fascinating candidates as molecular catalyst for H2 evolution. In that regard, creation and application of hybridized systems consist of 3d-transition metal ion and multifunctional organic ligand(s), which possess light absorbing property and protonic/electronic-flexibility, should be of great interest and importance. We report here on the light-driven H2 evolutions from a new system containing 3d-transition metal ions and multifunctional organic ligands. The structural and spectroscopic properties of complexes, which play the key role in H2 evolution reaction, will also be presented. [3] [1] Lewis, N. S.; Nocera, D. G. Proc. Natl. Acad. Sci. U. S. A. 2006, 103, 1572915735. [2] (a) http://element.sci.hokudai.ac.jp/~element/ (b) Nakamura, E.; Sato, K. Nat. Mater. 2011, 10, 158-161. [3] Matsumoto, T.; Ueno, S.; Wakizaka, M.; Yano, H.; Kobayashi, A.; Nakayama, A.; Taketsugu, T.; Chang, H.-C.; Kato, M. to be submitted.

Keywords: Light-driven hydrogen evolution, 3d-transition metal, multifunctional ligand

At present, platinum catalyst are used for the proton reduction in fuel cells. The challenge is now to replace the expensive and limited platinum metal by non-noble metal complexes. Several coordination metal complexes have already been explored for the electrocatalytic hydrogen production. Among them, cobalt bisglyoxime complexes are reputed as efficient catalysts,[1] but the mechanism for hydrogen production is still controversial. Electrochemical investigation of a boron-capped tris(glyoximato)cobalt clathrochelate complex (figure 1) in presence of acid reveals that the catalytic activity toward hydrogen evolution results from an electrodeposition of cobalt-containing nanoparticles on the electrode surface at a modest cathodic potential. [2] The deposited particles act as remarkably active catalysts for H2 production in water at pH 7. The above mentioned non noble metal complex previously described as a homogeneous catalyst1f is in fact the precursor of a heterogeneous catalyst. Joining these results to recent reports concerning several oxygen-evolving catalysts [3] call for reevaluation of systems described so far as molecular homogeneous catalysts.

Figure 1 [1] (a) Connolly, P.; Espenson, J. H. Inorg. Chem. 1986, 25, 2684., (b) Razavet, M.; Artero, V.; Fontecave, M. Inorg. Chem. 2005, 44,478 (c) Hu, X.; Cossairt, B. M.; Brunschwig, B. S.; Lewis, N. S.; Peters, J. C. Chem. Commun. 2005, 4723. (d) Baffert, C.; Artero, V.; Fontecave, M. Inorg. Chem. 2007, 46, 1817 (e) Hu, X.; Brunschwig, B.M.; Peters, J. C. J. Am. Chem. Soc. 2007, 129, 8988 (f) Pantani O., Naskar S., Guillot R., Millet P., Anxolabéhère-Mallart E., Aukauloo A. Angew. Chem. Int.Ed.Engl, 2008, 47, 9948. [2] Anxolabéhère-Mallart, E.; Costentin, C.; Fournier, M.; Nowak, S.; Robert, M.; Savéant, J-M. J. Am. Chem. Soc. 2012, 134, 6104. [3](a) Hocking, R. K.; Brimblecombe, R.; Chang, L. Y.; Singh, A.; Cheah, M. H.; Glover, C.; Casey, W. H.; Spiccia, L. Nat. Chem. 2011, 3, 461. (b) Stracke, J. J.; Finke, R. G. J. Am. Chem. Soc. 2011, 133, 14872.

Keywords: Co clathrochelate, nanoparticles, H2 evolution

MS.A2.C.04 Visible Light Responsive Semiconductor Nanowire Given by Metal Complex-Based Strategy Kenji Saito,a,b Akihiko Kudo,c and Shunichi Fukuzumib, aJapan Science and Technology Agency (JST), Saitama (Japan), bDepartment of Materials and Life Science, ALCA (JST), Osaka University (Japan), c Department of Applied Chemistry, Tokyo University of Science (Japan). E-mail: [email protected] Considerable efforts have so far been made to develop semiconductor photocatalysts for solar hydrogen production from

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Co Clathrochelate as Precursor for Electrodeposition of Nanoparticles Catalyzing H2 Evolution in Water Elodie Anxolabéhère-Mallart, Cyrille Costentin, Maxime Fournier, Sophie Nowak, Marc Robert, and Jean-Michel Savéant, Univ Paris Diderot, Sorbonne Paris Cité, Laboratoire d’Electrochimie Moléculaire, UMR 7591 CNRS, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France. E-mail: [email protected]

Microsymposia water [1]. Among them, semiconductor nanowire photocatalysts have merited special attention due to its relatively large surface area and small particle size, both of which generally contribute to enhancement of photocatalytic performance compared with the corresponding bulk materials [2]. However, enhancement of the performance under visible light remains as a great challenge. We report herein preparation of TT phase of niobium pentoxide nanowire doped with Rh (TT-Nb2O5NW:Rh) and their photocatalytic performance under visible light irradiation. Mixture of a niobium complex, (NH4)3[NbO(Ox)3]•H2O (Ox = oxalate) with RhCl3 was heated at 403-498 K in trioctylamine of a structure-directing solvent. The resulting suspension was filtered, and the solids were calcined in air at 773 K to obtain TT-Nb2O5-NW:Rh. A reaction cell with a top window made of Pyrex and 300 W Xe-arc lamp were used for H2 evolution from an aqueous methanol solution and O2 evolution from an aqueous silver nitrate solution. These reaction cells were connected to a gas–closed circulation system with on-line gas chromatograph. Crystal structure of the powder obtained was characterized by XRD and was confirmed to be single phase. SEM image of TT-Nb2O5NW:Rh indicated nanowire morphology (Figure 1) being different from those of the bulky counterpart prepared by a solid state reaction. Electron diffraction indicated that the sample possessed single crystalline nature and this observation was further supported by HRTEM image showing clear lattice fringes. The Rh doping afforded a new absorption band in the visible region. TT-Nb2O5-NW:Rh showed photocatalytic activities for both H2 and O2 evolution from aqueous solutions containing sacrificial reagents under visible light irradiation (l > 420 nm).

Unexpected enhancement of the catalytic activity by reducing the size of metal nanoparticles attracted much attention as a new class of materials for advanced catalysis. However, precise control of the number of atoms (metal) in the nanoparticle has been an unprecedented challenge. We previously succeeded a fine control of complexation using phenylazomethine dendrimer ligands, which can assemble specific number of metal ions. A template synthesis of the nanoparticles (Fig. 1A) could be achieved as a universal method using this dendrimer. Platinum nanoparticles, of which formulae are Pt12, Pt28 and Pt60, were synthesized from the complex of PtCl4 and phenylazomethine dendrimer with a tetraphenylmethane core (DPAG4-TPM) with the corresponding stoichiometry. Reduction by NaBH4 successfully afforded the platinum nanoparticles, of which sizes were characterized by TEM (Fig. 1B, C, D). The formation and size control of the nanoparticles were also supported by EXAFS, XPS and ESI-TOFMass spectra. Many previous studies have reported that smaller platinum nanoparticles with a size under 2 nm exhibited lower catalytic ORR performances. However, the present platinum particle synthesized with the dendrimer template exhibited a very high catalytic activity per platinum weight. The catalytic activity was measured by rotating disk voltammetry (RDV) method under an oxygen saturating condition. Kinetic current density values obtained using Koutecky-Levich equation provided higher mass activities of the smaller particles. The kinetic limiting current normalized by the weight of platinum was increased, and reached a 13-times higher activity than the commercial Pt/C catalyst (platinum nanopoarticle on carbon support) with a size of about 2-4 nm.

Figure 1. SEM image of TT-Nb2O5-NW:Rh.

Figure.1 (A) Synthesis of size-specific Pt nanoparticles using a dendrimer template, (B) A TEM image of Pt12, (C) Pt28 and (D) Pt60 synthesized using DPAG4-TPM.

[1] A. Kudo, Y. Miseki, Chem. Soc. Rev., 2009, 38, 253-278. [2] K. Saito, A. Kudo, Inorg. Chem., 2010, 49, 2017-2019.

Keywords: niobium photocatalyst

complex,

semiconductor

nanowire,

MS.A2.C.05 Subnanometre Platinum Particles as Excellent Electrocatalysts for Oxygen Reduction Reaction Takane Imaoka, Kimihisa Yamamoto, Chemical Resources Laboratory, Tokyo Institute of Technology (Japan). E-mail: [email protected]. ac.jp

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[1] K. Yamamoto, T. Imaoka, W.-J. Chun, O. Enoki, H. Katoh, M. Takenaga, A. Sonoi Nature Chem. 2009, 1, 397-402.

Keywords: dendrimers, platinum, oxygen reduction reaction

MS.A2.C.06 Ru Dyes bearing Pyridine-Quinoline Hybrid Ligands for DyeSensitized Solar Cells Georgios C. Vougioukalakis, Thomas Stergiopoulos, Polycarpos Falaras, Institute of Physical Chemistry, National Center for Scientific Research Demokritos, Agia Paraskevi (Greece). E-mail: vougiouk@ chem.demokritos.gr; [email protected]

Dye-sensitized solar cells (DSCs) provide an appealing alternative to the conventional solid-state cells. This is mainly due to their ability to work indoors and under subdued light conditions, their potential transparency and flexibility, their invariant efficiency to the operating temperature, and their relatively low production cost [1]. The present work focuses on the synthesis and characterization of two novel Ru(II)-based complexes bearing an unsymmetrical pyridinequinoline hybrid ligand. These new complexes were prepared in order to be used as alternative dyes in DSCs. Their photovoltaic performance and hydrophobic properties were studied in detail. The pyridinequinoline ligand in question is tailor-designed with a long aromatic conjugated moiety to increase the absorption extinction coefficient of the main metal-to-ligand charge transfer (MLCT) band, extend the response towards the red part of the solar spectrum, and enhance the hydrophobicity of the sensitized TiO2 photoelectrode. Both dyes present substantial overall power conversion efficiencies. Under 1 sun illumination (AM1.5G), the most efficient dye affords 4.4% power conversion efficiency, a value that is about 50 to 60% of that obtained with the standard Z907 dye under similar experimental conditions.

on Cat themselves and on the surrounding chemical species. Actual measurements of the electrical and the magnetic properties under dark supported that these salts were nearly diamagnetic semiconductors under dark, i.e. ideal dark states for our purpose. Under UV irradiation rather large photocurrent Iph (Iph/Idark ~ 10-1000; Idark = observed current under dark) and localised spins were observed. In addition, in a salt, convincing evidence (Kondo effect) was obtained indicating the interaction between carriers and localised spins under UV irradiation. These salts exhibited response only to UV unlike the existing PCs. One could explain such a unique photoconduction by considering the CT transitions between Ni(dmit)2 and Cat triggered by UV. One could describe this situation by an optical control of electronic states between a simple salt (diamagnetic insulator) and a CT salt (magnetic conductor) in the solid state in a reversible way.

[1] G. C. Vougioukalakis, A. I. Philippopoulos, T. Stergiopoulos, P. Falaras, Coord. Chem. Rev. 2011, 255, 2602-2621.

[1] O. Skorka, D. Joseph, Sensors, 2011, 11, 4512-4538. [2] S. Kasap, et al. Sensors, 2011, 11, 5112-5157. [3] P. Cassoux,et al. Coord. Chem. Rev. 1991, 110, 115-160.

Keywords: DSCs, ruthenium, extended conjugation

Keywords: conductors

photoconductors,

spintronics,

dilute

magnetic

MS.A2.C.07 Simultaneous Control of Carriers and Localised Spins by Light Toshio Naito,a Tomoaki Karasudani,a Shigeki Mori,a Keishi Ohara,a Kensuke Konishi,a Takahiro Takano,b Yukihiro Takahashi,b,c Tamotsu Inabe,b,c aGraduate School of Science and Engineering, Ehime University, Ehime, (Japan). bGraduate School of Science, Hokkaido University, Hokkaido, (Japan). cGraduate School of Chemical Sciences and Engineering, Hokkaido University, Hokkaido, (Japan). E-mail: [email protected] Photoconductors (PCs) reversibly become conducting only at excited states under irradiation. Because of this property they are applied in sensors/detectors and energy converters such as chargecoupled devices (CCD), complimentary metal-oxide-semiconductor (CMOS) image sensors, and photovoltaic cells [1,2]. In all the known PCs, one can control only the carriers by photoexcitation. We have developed a new type of PCs (Cat)[Ni(dmit)2]2 {Cat = N,N’-dialkyl bipyridinium derivative cations, Ni(dmit)2 = bis(1,3-dithiole-2-thione4,5-dithiolato)nickelate(III)}, in which UV irradiation reversibly and simultaneously generates both carriers and localized spins on Ni(dmit)2 and Cat, respectively, on the bases of the ESR and the resistivity measurements. What is more, we have found interaction between the carriers and the localized spins, which will enable us to control and detect the localised spins through carriers and vice versa. Importance and novelty lie in this type of PCs in that it is a first step to a future technology “opto-spintronics”, i.e. magneto-electronic devices controlled by light for remote control. The Ni(dmit)2 molecules are known to be suitable for the development of conducting materials [3], because they often become stable radical anions [Ni(dmit)2]n- (0 ≤ n ≤ 2) and comprise a sulfursulfur network in the solid state, serving as conduction pathways for unpaired electrons on the radical anions. On the other hand, all the cations (Cat) selected in this work are of closed-shell (free of unpaired electrons) under dark and have photo-induced redox activity, which would bring about electron transfer with the surrounding chemical species under UV irradiation. This redox property would serve as a switch of appearance/disappearance of unpaired electrons

MS.A2.C.08 Volatile Molecular Precursor for the Lithium Ion Battery Cathode Evgeny V. Dikarev, Department of Chemistry, University at Albany, SUNY, Albany, NY, (USA). E-mail: [email protected] One of the most important active materials for the positive electrode of lithium ion batteries is lithium – manganese oxide, LiMn2O4. This compound has a spinel-type structure that can release Li+ ions upon oxidation of transition metal centers. Abundant Mn resources, low toxicity, high electronic and lithium ion conductivity as well as an excellent rate capacity have made LiMn2O4 a leading candidate for vehicle battery applications. The first heterometallic single-source precursor for the lithium – manganese cathode material is reported. Heterometallic b-diketonate LiMn2(β-dik)5 has been obtained [1] in high yield by simple one-step solid state reactions employing commercially available reagents. Substantial scale-up preparation can be achieved using solution approach. Crystal structure of precursor contains discrete trinuclear molecules with a proper Li:Mn = 1:2 metal ratio for the desired decomposition product. The complex is highly volatile above 100 o C and exhibits a congruent sublimation. Diketonate compound is soluble in all common solvents and retains its heterometallic structure in solutions of non-coordinating solvents. Molecular precursor is relatively stable in moist air and exhibits clean, low-temperature decomposition that occurs in a single step. Decomposition of heterometallic precursor in air/oxygen atmosphere was shown to result in nanosized particles of spinel-type oxide LiMn2O4. The prospects and further developments of single-source precursor approach for the synthesis of different types of cathode materials will be discussed. [1] A. Navulla, L. Huynh, Z. Wei, A. S. Filatov, E. V. Dikarev, J. Am. Chem. Soc., 2012, 134, 5762−5765.

Keywords: lithium ion batteries, cathode materials, single-source precursors

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Microsymposia

Microsymposia MS.A2.C.09

MS.A2.C.10

The Co-ordination Chemistry of Surfaces - New Catalysts for the Hydrogen Evolution Reaction Anthony Masters,a Alan Bond,b Michael Burke,a Leo Corcillius,a Vincent Lau,a Thomas Maschmeyer,a Leon van de Water,a Laboratory of Advanced Catalysis for Sustainability, School of Chemistry, F11, The University of Sydney, NSW, 2006, (Australia). b School of Chemistry, Monash University, Victoria, 3800, (Australia). E-mail: a.masters@ chem.usyd.edu.au

Development of Hybrid Photovoltaic Cells with Organic-Inorganic Coordination Compounds Ayumi Ishii, Tsutomu Miyasaka, Graduate School of Engineering, Toin University of Yokohama (Japan). E-mail: [email protected]

The hydrogen evolution reaction (HER, H+ + e- ↔ ½H2) is one of the main routes for the production of molecular hydrogen. This electrochemical process can be made environmentally sustainable by combining the reaction with a source of renewable electricity. Presently, the most efficient catalysts for the HER are noble metals such as platinum.[1] However the reserves of these metals are insufficient to meet projected needs, so it is important to find alternative electrocatalytic materials that are highly active, yet inexpensive and abundant. Our group focuses on developing heterogeneous photoelectrochemical catalysts for the solar production of hydrogen. In this presentation, we highlight our development of an efficient replacement to the typical expensive noble metal as a HER electrocatalyst by controlling the surface co-ordination chemistry of molybdenum disulfide (MoS2). Recent studies have shown that MoS2 nanoparticles have a high HER electrocatalytic activity with the active sites at the edge of the planar crystal.[2] This demonstrates that they can be a more economical alternative to platinum metal, the most active of noble metals for HER. The challenge is to synthesise, in a bulk-scale synthesis procedure, MoS2 particles of appropriate dimensions and optimized morphology to display HER catalysis. Here, we demonstrate the thermosynthesis of HER-active MoS2 particles from ammonium tetrathiomolybdate using ionic liquids (IL) as the recyclable synthesis medium. The use of IL-media for material syntheses has attracted significant interest, especially due to their ability to stabilize high energy surfaces or morphological features during the crystal growth phase.[3,4] The ionic liquids control the surface co-ordination chemistry of developing MoS2 layers, producing nanoparticulate catalysts that differ from the bulk material not only in terms of morphology, as compared to the synthesis without IL, but also in that they have significantly higher activity for HER (Figure).

Design of photovoltaic interfaces by chemical reactions of inorganic materials (semiconductors), organic molecules and its junctions with organic semiconductors creates new energetics of carrier transfer and allows wider tuning of photo-voltage without losing photocurrent density. Here, we report a thin solid-state photovoltaic cell composed of organic-inorganic hybrid film, forming the dye-metal charge-transfer coordination compounds as the sensitizer monolayer sandwiched between inorganic and organic semiconductor. A thin solid-state sensitized photovoltaic cell was fabricated by composing organic and inorganic hetero junctions of TiO2/ anthraquinone/perylene, in which anthraquinone (AQ), a visiblelight sensitizer, coordinates to Ti4+ of the metal oxide, forming a monomolecular layer of metal-ligand complex. The coordination bonds create a new LMCT (ligand to metal charge transfer) absorption band and induce rectified charge transfer from AQ to TiO2, leading to photocurrent generation. Photovoltaic junctions were prepared by coating a 100 nm-thick hole transport layer (HTL), perylene, on the AQ-coordinated TiO2 surface by the vapor deposition method. Perylene exhibits a high hole mobility in crystalline state. The film was grown as a crystalline phase at a deposition rate of ~0.1 Å/s and a substrate temperature of 100 °C, while an amorphous phase was obtained with rapid deposition of more than 5 Å/s at room temperature. The crystalline phase in the thin film corresponded to the single crystal b-phase. In the b-phase of perylene, 2D intermolecular p-p interactions are formed along the (001) crystal plane that corresponds to the carrier conductive direction. Photocurrent density-voltage (J-V) characteristics for the TiO2AQ-HTL photovoltaic cells were measured under exposure to AM 1.5 sunlight (100 mW/cm2) on a solar simulator. A large increase in photocurrent was shown by AQ coordination with Ti4+ on the metal oxide surface. High efficiency in electron injection is assumed to occur by the ligand to metal charge transfer in the excited Ti-AQ complex. This Ti-AQ photo-anode is coupled with HTL whose solid– state properties strongly affect carrier transport and cell performance. Perylene HTL prepared in crystalline phase was found to significantly enhance the photocurrent density and photovoltage as a result of increased hole conductivity over the amorphous phase. As a result, the organic-inorganic hybrid thin film photocell was capable of generating a high open-circuit voltage 1.18 V with photoelectric conversion efficiency up to 1.3 %. Additionally, for efficiency enhancement, the hybrid photoelectrode was improved in light harvesting by increasing optical absorption, which was under progress by way of introducing high surface area TiO2 networks into the cell structure.

Cyclic voltammogram of the MoS2 showing higher HER catalytic activity. [1] B. E. Conway, G. Jerkiewicz, Electrochim. Acta, 2000, 45, 4075-4083. [2] T. F. Jaramillo, K. P. Jørgensen, J. Bonde, J. H. Nielsen, S. Horch, I. Chorkendorff, Science, 2007, 317, 100. [3] X. Zhou, Z. Xie, Z. Jiang, Q. Kuang, S. Zhang, T. Xu, R. Huang, L. Zheng, Chem. Comm., 2005, 5572-5574. [4] T. Xu, X. Zhou, Z. Jiang, Q. Kuang, Z. Xie, L. Zheng, Cryst. Growth & Design, 2009, 9, 192-196.

Keywords: Molybdenum Sulfide, HER Catalyst, Surface

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Keywords: Photovoltaic, Hybrid, Dye-sensitized

Microsymposia MS.A2.C.11 Coordination polymer electrode for Li-ion battery cathode Tomoyuki Matsuda,a Yutaka Moritomo,a,b aGraduate School of Pure and Applied Science, University of Tsukuba, Tsukuba, (Japan). bTIMS, University of Tsukuba, Tsukuba (Japan). E-mail: matsuda.tomoyuki. [email protected]

MSA2

Next-generation electrode materials are being intensively explored to achieve a high-power and high-capacity Li-ion secondary battery (LIB) for use in high-power applications such as electric vehicles. The coordination polymer frameworks are quite appropriate system to achieve such an electrode material, since the frameworks contain redox active metal sites and have enough space for Li ion storage. In this presentation, we show our recent results of electrochemicallydeposited thin films of Prussian blue analogues for the LIB cathode. [1-4] We prepared the electrochemically-deposited thin film of Prussian blue analogue, Li1.32Mn[Fe(CN)6]0.83∙3.5H2O, and investigated the charge/discharge properties. The thin film showed a good cyclability (= 87% of the initial value at 100 cycles) with a high charge capacity (= 128 mA h g−1), which is due to the two-electron reactions of [FeII(CN)6]4−/ [FeIII(CN)6]3− and Mn2+/Mn3+ without structural phase transition.1,2 Figure 1 shows the discharge properties of the nanosized LixMn[Fe(CN)6]0.81∙3.0H2O thin film which realized an extremely high discharge rate at 3000 C (delithiation process in 1.2 s) with a high capacity (= 85 mA h g−1) as well as the good cyclability (no reduction was observed after 30 cycles at 3000 C).4 The power density estimated from the discharge rate was 612 W g−1, and even exceeds the electric double layer capacitor. The ultrafast response is originated in the large Li-ion diffusion constant inherent to the 3-dimensional Prussian blue framework as well as the ideal electric contact between the active material and the collecting ITO electrode. Our observation indicated that the thin-film electrodes of the Prussian blue analogues are the new series of promising candidate cathode material for the high-power LIBs. In addition, the Na1.32Mn[Fe(CN)6]0.83∙3.5H2O electrode can be used even for the Na ion secondary battery cathode.

Figure 1. Discharge curves of the thin film electrode of LixMn[Fe(CN)6]0.81·3.0H2O with the thickness of 0.12 mm against the Li metal. [1] T. Matsuda, Y. Moritomo, Appl. phys. Exp., 2011, 4, 047101. [2] T. Matsuda, Y. Moritomo, J. Nanotech., 2012, in press. [3] Y. Moritomo, M. Takachi, Y. Kurihara, T. Matsuda, Appl. Phys. Exp., 2012, 5, 041801. [4] Y. Moritomo, X. H. Zhu, T. Matsuda, submitted.

Keywords: Lithium-ion battery, Coordination polymer framework

Prussian

blue

analogue,

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9 - 13 September 2012

Microsymposia MS.A3.KN1 Mesoscopic Chemistry by Porous Coordination Polymers Susumu Kitagawa, Institute for Integrated Cell-Material Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, (Japan) and ERATO Integrated Pores Project, Japan Science and Technology Agency, Kyoto Re-search Park Bldg#3, Shimogyo-ku, Kyoto 600-8815, (Japan). E-mail: [email protected]

[1] S. Kitagawa, et. al., Bull. Chem. Soc. Jpn (Accounts). 1998, 71, 1739. [2] S. Horike, et.al. Nature Chemistry, 2009, 1, 695. [3] T. Tsuruoka, et.al.,Angew. Chem. Int. Ed., 2009, 48, 4739.

Keywords: Porous Coordination Polymer, Framework, Coordination Modulation

Metal-Organic

MS.A3.KN2 Hydrogen Storage and Carbon Monoxide Capture in Porous Metal-Organic Frameworks Myunghyun Paik Suha, Dea Woon Lim,a and Hye Jung Park,a a Department of Chemistry, Seoul National University, Seoul, (Republic of Korea). E-mail: [email protected] Hydrogen storage and carbon dioxide capture become increasingly important issues in recent scientific community because of the need for replacing current carbon-based energy source and the implication of carbon dioxide in global warming. Metal-organic frameworks (MOFs) or porous coordination polymers (PCPs) have attracted great attention because they have potential in such applications. We have synthesized various MOFs and PCPs from metal and organic building blocks via solvothermal reactions and room temperature self-assembly. Our MOFs and PCPs show exceptionally high H2 storage capacities,[1] and highly selective CO2 capture abilities,[2] depending on the design strategies. Hydrogen storage capacities of MOFs could be increased by generating greater surface area, creating vacant coordination sites on the metal ions, including free metal ions or organic molecules in the pores, and embedding metal nanoparticles in the channels.[1] Highly selective CO2 capture with PCPs or MOFs was achieved by tailoring their flexibilities such that the pores could open and close depending on CO2 pressure and temperature, while not responding to other gases, and reducing the pore size of the flexible framework via post-synthetic insertion of a bridging linker.[2]

[1] (a) M. P. Suh, H. J. Park, T. K. Prasad, D. W. Lim, Chem. Rev. 2012, 112, 782-835. (b) E. Y. Lee, S. Y. Jang, M. P. Suh, J. Am. Chem. Soc. 2005, 127, 6374-6381. (c) Y. G. Lee, H. R. Moon, Y. E. Cheon, M. P. Suh, Angew. Chem. Int. Ed. 2008, 47, 7741-7745. (d) Y. E. Cheon, M. P. Suh, Angew. Chem. Int. Edit. 2009, 48, 2899-2903. (e) T. K. Prasad, D. H. Hong, M. P. Suh, Chem. Eur. J. 2010, 16, 14043-14050. (f) H. J. Park, D.-W. Lim, W. S. Yang, T. -R. Oh, Chem. Eur. J. 2011, 17, 7251-7260. (g) H. J. Park, M. P. Suh, Chem. Commun. 2012, 3400-3402. [2] (a) H. S. Choi, M. P. ; Suh, Angew. Chem. Int. Ed. 2009, 48, 6865-6869 (b) H. J. Park, Y. E. ; Cheon, M. P. ; Suh, Chem. Eur. J. 2010, 16, 11662-11669. (c) T. K. Kim, M. P. Suh, Chem. Commun. 2011, 47, 4258-4260.

Keywords: Metal-Organic Frameworks, Hydrogen Storage, Carbon Monoxide Capture

MS.A3.I1 In situ studies: synthesis, reactions and properties of MOFs Lee Brammer,a Paul Smart, a Charles A. Mason, a Jason R. Loader,a Iñigo J. Vitorica-Yrezabal,a Anthony J. H. M. Meijer,a Alastair J. Florence,b Ashleigh J. Fletcher,c aDept. of Chemistry, University of Sheffield, Sheffield, UK. bStrathclyde Institue of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE, Scotland. cDept. of Chemical and Process Engineering, University of Strathclyde, Glasgow G1 1XJ, Scotland. Email: lee.brammer@ sheffield.ac.uk Metal-organic frameworks (MOFs) are periodic porous materials based upon coordination chemistry. They have been developed for applications ranging from gas sorption and other forms of molecular entrapment, catalysis, applications in photophysics and magnetism, and biomedical applications.[1,2] MOFs are most commonly synthesised via a “one-pot” selfassembly approach from chemically simple components, using solvothermal or other solution-phase methods. Although effective, this approach limits the diversity of accessible materials, and in particular the chemical diversity of the interior space within MOFs, since selfassembly involving functional group-rich organic ligands is more difficult to control. Increased chemical diversity in MOFs would be advantageous in developing greater specificity for many of the myriad target applications for MOFs. One solution to this problem that has developed rapidly in the past few years is post-synthetic modification of MOFs,[3] in which chemical transformations, often of organic functional groups, are made after initial assembly of the MOF material. This presentation will focus on our studies of chemical reactions and transformations involving MOFs[4] and related coordination polymers[5] and builds upon some of our parallel work on gas-solid reactions involving molecular crystals.[6] The present studies are aimed at understanding reaction behaviour involving MOFs and with a view to developing synthetic methodology, accompanied by suitable characterisation methods, to enable the design and construction of novel materials. Our approach has been to post-synthetically modify coordination network materials of lower dimensionality, often increasing network dimensionality (1D to 2D or 2D to 3D), but also introducing new ligands and new functional groups that have proven more difficult or not possible to introduce in direct one-pot self-assembly approaches. Examples will be selected to illustrate the

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Well-designed metal–organic hybrid porous materials—socalled porous coordination polymers (PCPs)—can be made from an assembly of organic linkers with metal ions, providing a variety of porous properties. We have predicted and developed new properties of PCPs, which are based on flexibility of porous frameworks, and coined a term, soft porous crystal[1,2]. Toward the future of PCPs, I would show a new dimension of the materials with concepts of miniaturization and hybridization in mesoscopic regime. For the purpose we have developed a new synthetic method, called “coordination modulation” for creating size and shape controlled crystals in the mesoscopic domain[3]. Miniaturizing the size of PCP crystals to mesoscopic scale by functionalizing the crystal interfaces will provide further opportunities to integrate novel functions into the materials without changing the characteristic features of so-called bulk PCP crystal itself.

Microsymposia methodology and the types of materials that can be synthesised. The presentation will emphasise the needs and challenges of characterisation of the synthesised materials. A combined approach using, in particular, X-ray powder diffraction, together with spectroscopy and DFT calculations (molecular and periodic) has been taken to address this important issue. [1] See issue of Chemical Reviews devoted to MOFs: Chem. Rev. 2012, 112, 673-1268. [2] See issue of Chemical Society Reviews devoted to MOFs: Chem. Soc. Rev. 2009, 38, 1201-1508. [3] S. R. Cohen, Chem. Science 2010, 1, 32. [4] (a) S. M. Hawxwell et al., Chem. Commun. 2007, 1532. (b) P. Smart et al., 2012, submitted. [5] (a) S. Libri et al., Angew. Chem. Int. Ed. 2008, 47, 1693. (b) I. J. Vitorica-Yrezabal et al., 2012, submitted. [6] (a) G. Mínguez Espallargas et al., J. Am. Chem. Soc. 2007, 129, 15606. (b) G. Mínguez Espallargas et al., Angew. Chem. Int. Ed. 2010, 49, 8892.

Keywords: metal-organic frameworks, solid-state reactions, materials synthesis

MS.A3.I2 Metal-Organic Frameworks: Synthesis and Applications in Hydrogen Storage and Photochemistry Neil R. Champness,a aSchool of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK. E-mail: Neil. [email protected] Non-covalent directional intermolecular interactions provide a pre-determined recognition pathway which has been widely exploited in supramolecular chemistry to form functional nanostructures in both solution and in the solid-state. One particular area of extensive current interest has been the exploitation of coordination bonds to prepare solid-state polymeric architectures. By controlling the geometry of the polymer components, metal cation and ligand, the structure of the resulting material can, to some extent, be predicted and controlled. As a result it is possible to design materials with specific properties [1], notably porosity for gas storage applications [2]. This lecture will present the successful application of the ‘building-block’ methodology [3] in preparing a range of solid-state structures commonly known as coordination polymers or metalorganic frameworks (MOFs). The talk will highlight the use of MOFs to host photoactive species [4] modifying the properties of the incorporated species (see Fig. a,b) and allowing direct crystallographic characterisation of structural transformations upon photoexcitation. Particular focus will be given to our recent efforts in preparing porous MOFs for gas storage applications [2,5,6]. Examples will focus predominantly on the storage of H2 gas for ultimate application in the automobile industry, illustrating the influence of pore framework structure [5] and introduce the concept of using anionic MOFs to control hysteresis in gas adsorption (see Fig. c) [6].

[1] N.R. Champness, Dalton Trans., 2011, 40, 10311-10315. [2] X. Lin, J. Jia, P. Hubberstey, M. Schröder, N.R. Champness, CrystEngComm, 2007, 9, 438-448. [3] B. F. Hoskins, R. Robson, J. Am. Chem. Soc., 1990, 112, 1546-1554. [4] A.J. Blake, N.R. Champness, T.L. Easun, D.R. Allan, H. Nowell, M.W. George, J. Jia, X.-Z. Sun, Nat. Chem., 2010, 2, 688-694. [5] Y. Yan, X. Lin, S. Yang, A.J. Blake, A. Dailly, N.R. Champness, P. Hubberstey, M. Schröder, Chem. Commun., 2009, 1025-1027. [6] S. Yang, X. Lin, A.J. Blake, G.S. Walker, P. Hubberstey, N.R. Champness, M. Schröder, Nat. Chem., 2009, 1, 487-493.

Keywords: Metal-Organic Framework, Hydrogen Storage, Photochemistry

MS.A3.I3 H-Bond Sustained Open-Framework Materials Jean-Pascal Sutter,a Georges Mouchaham,a Nans Roques,a aLaboratoire de Chimie de Coordination du CNRS, Toulouse (France). E-mail: [email protected] We will discuss an approach using weak bonds such as chargeassisted H-bonds for the construction of open-framework materials. These supramolecular porous architectures are achieved by selfassembly of anionic metal complexes with organic cations respectively acting as H-bond acceptors and donors [1]. Metal-organic units with given geometries and linking abilities form the network nodes, and contribute to govern the net topology through their association with organic linkers. Recent achievements using metal-oxalate complexes and various organic cations as building-blocks will be presented, including a material showing a potential porosity of ca. 60% and very versatile guest sorption capabilities.

[1] a) F. Thétiot, C. Duhayon, T. S. Venkatakrishnan, J.-P. Sutter Crystal Growth & Des. 2008, 8, 1870; b) G. Mouchaham, N. Roques, A. Kaiba, P. Guionneau, J.-P. Sutter CrystEngComm 2010, 12, 3496; c) G. Mouchaham, N. Roques, I. Imaz, C. Duhayon, J.-P. Sutter Cryst. Growth & Des. 2010, 10, 4906; d) G. Mouchaham, N. Roques, S. Brandès, C. Duhayon, J.-P. Sutter Cryst. Growth & Des. 2011, 11, 5424.

Keywords: MOF, H-bond, supramolecular materials

MS.A3.C.01 Photoluminescent and Catalytic Lanthanide-Phosphonate MetalOrganic Frameworks Filipe A. Almeida Paz, University of Aveiro, CICECO, Department of Chemistry, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal). E-mail: [email protected] Metal-Organic Frameworks (MOFs) are hybrid compounds prepared from the combination of bridging organic ligands with metallic centres (typically d-block elements). Besides the peculiar topological architectures that may be discovered, worldwide research is now mainly concentrated into the development of functional materials by taking advantage of the simultaneous presence of

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Microsymposia Spin crossover (SCO) complexes and porous coordination polymers (PCPs) are attract much attentions as molecular-based components of new advanced materials respectively. The formar produces changes in magnetic, optical, dielectric and structural properties associated with switching the electron configurations, and the latter exhibit various porous functions, e.g. selective adsorption, separation, catalytic reaction, etc., based on their permanent and designable regular microporous structure consists of flexible coordination bonds. We have researched coorrelation between the magnetic and porous properties by incorporating magnetic properties in the framework of PCPs.[1-3] Here I talk about magnetically-bistable Hofmann type PCPs, {Fe(pz) [M(CN)4]} (pz = pyrazine; MII = Pt (1), Pd (2), Ni (3)), providing functional space incorporating SCO subunits and guest interactive sites. Compounds 1−3 have three-dimensional pillared-layer-type porous framework with coordinatively-unsaturated MII centers as open metal site (OMS), and exhibit a first-order spin transition with ca. 20 K wide hysteresis near room temperature. The spin states are reversibly switched by the uptake and release of various guest molecules. Several guest molecules stabilized different spin state depending on the MII, which suggests significant effect of OMS on the host-guest interaction in the framework. Also, the spin transition behaviors, spin transition temperature and hystteresis width, are modulated by the combination of guest molecule and OMS.

MSA3

organic and inorganic components, both of which can per se induce functionality. MOFs constitute, thus, a rich playground for the design of remarkable functional materials [1], many of which with direct industrial applications and that can be prepared in large scale [2]. This presentation will summarize the on-going efforts of our research group towards the development of novel functional MOFs based on the selfassembly of lanthanide centres with polyphosphonate organic linkers. The reaction between highly flexible organic ligands based on chelating phosphonic acid groups, such as (carboxymethyl)iminodi(methylphosphonic acid) [3] and nitrilotris(methylenephosphonic acid) [4], with lanthanide cations have produced a handful of multifunctional layered materials that exhibit visible photoluminescence, interesting heterogeneous catalytic activity (e.g., conversion of D-xylose into furfural or ring-opening reactions of styrene oxide), or can even be employed as potential MRI contrast agents. Our efforts to chemically modify the organic linkers (e.g., by the inclusion of aromatic rings, some of which fluorinated) in order to boost the photoluminescent properties will also be described. We have, thus, prepared the novel (benzene-1,3,5-triyltris(methylene)) triphosphonic acid (H6bmt) and ((2,4,6-trifluorobenzene-1,3,5-triyl) tris(methylene)triphosphonic acid organic linkers [5] which permit an effective sensitization of the lanthanide centres: e.g., the zeolitic [(La0.95Tb0.05)2(H3bmt)2-(H2O)2]∙H2O material has the remarkable absolute emission quantum yield of ca. 46% [5a]. Because many of these materials were isolated as microcrystalline powders, our strategy to fully elucidate the fine structural features of these families and based on the combination of powder X-ray diffraction, solid-state NMR and photoluminescence studies will also be described. Fundação para a Ciência e a Tecnologia (FCT, Portugal), the European Union, QREN, FEDER, COMPETE and Laboratório Associado Centro de Investigação em Materiais Cerâmicos e Compósitos, CICECO (PEst-C/CTM/LA0011/2011) are gratefully acknowledged for their general funding scheme. FCT is also thanked for funding the R&D project PTDC/QUI-QUI/098098/2008 (FCOMP01-0124-FEDER-010785), and for specific funding towards the purchase of the single-crystal diffractometer. [1] (a) M. O’Keeffe, O. M. Yaghi, Chem. Rev., 2012, 112, 675-702; (b) J. Rocha et al., Chem. Soc. Rev., 2011, 40, 926-940; (c) A. Bétard et al., Chem. Rev., 2012, 112, 1055-1083; (d) S. C. Xiang et al., Nat. Commun., 2011, 2, Article No. 204; (e) P. Horcajada et al., Chem. Rev., 2012, 112, 1232-1268; (f) F. A. A. Paz et al., Chem. Soc. Rev., 2012, 41, 1088-1110. [2] A. U. Czaja et al., Chem. Soc. Rev., 2009, 38, 1284-1293. [3] (a) L. Cunha-Silva et al., J. Mater. Chem., 2009, 19, 2618-1632; (b) G. A. Pereira et al., Inorg. Chem., 2010, 49, 2969-2974; (c) L. Cunha-Silva et al., Z. Kristallogr., 2009, 224, 261-272. [4] (a) L. Cunha-Silva et al., Chem. Mater., 2007, 19, 3527-3538; (b) P. Silva et al., J. Am. Chem. Soc., 2011, 133, 15120-15138. [5] (a) S. M. F. Vilela et al., J. Mater. Chem., 2012 (Submitted); (b) S. M. F. Vilela et al., Chem. Commun., 2012 (Submitted).

Keywords: MOFs, photoluminescence, catalysis

MS.A3.C.02 Magnetic Bistability Interlocking with Porous Functions in Porous Coordination Polymers Masaaki Ohba,a Ryo Ohtani,b Ko Yoneda,c Ana B. Gaspar,d M. Carmen Muñoz,e José A. Real,d Susumu Kitagawa,b,f aDepartment of Chemistry, Faculty of Science, Kyushu University, Fukuoka (Japan). bDepartment of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto (Japan). cFaculty of Science and Engineering, Saga University, Saga (Japan). dInstituto de Ciència Molecular, Universitat de València, València (Spain). eDepartament de Física Aplicada, Universitat Politècnica de València (Spain). fInstitute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Kyoto (Japan). E-mail: [email protected]

Figure 1 Hofmann type PCPs, {Fe(pz)[M(CN)4]} [1] M. Ohba, J. A. Real, S. Kitagawa, et al., Angew. Chem. Int. Ed. 2009, 48, 4767; ibid, 2009, 48, 8944. [2] M. Ohba, K. Yoneda, S. Kitagawa, Cryst. Eng. Comm., 2010, 2, 159. [3] R. Ohtani, S. Kitagawa, J. A. Real, M. Ohba, et al., J. Am. Chem. Soc., 2011, 133, 8600.

Keywords: Spin Transition, Porous Coordination Polymers, Magnetic Bistability

MS.A3.C.03 Dipyrrin Based Heterometallic MOFs Stéphane A. Baudron,a Antoine Béziau,a Dmitry Pogozhev,a Mir Wais Hosseini,a Laboratoire de Chimie de Coordination Organique, University of Strasbourg, Strasbourg, (France). E-mail: sbaudron@ unistra.fr Metal-Organic Frameworks (MOFs) and coordination polymers (CPs) have attracted considerable interest over the past few years owing to their potential application for gas storage or catalysis, for example. [1] While the vast majority of these compounds are homometallic, the synthesis of their heterometallic counterpart, M’MOFs, remains challenging.[2] Indeed, a one-pot synthetic approach can lead to a statistical mixture of homo- and hetero-metallic architectures.

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Microsymposia To circumvent this synthetic issue, a sequential strategy can be envisioned (see Figure below). The latter relies on the use of ligands bearing differentiated coordination sites hence allowing the stepwise elaboration of heterometallic architectures. Reaction of such a ligand with a first metal center leads to the formation of a metal complex, or metallatecton, bearing peripheral coordinating sites available for ligation to another metal center. Among the many potential differentiated ligands, dipyrrins, dpm, represent a particularly interesting class of compounds.[3] Indeed, their rather easy synthesis and functionalization as well as the monoanionic and chelating nature of their conjugate base have made them appealing candidates. In particular, the 5-aryl-dipyrrin derivatives have been successfully used for the elaboration of extended heterometallic architectures based on coordination as well as silver-p interactions. [4-5] We will present here our results obtained following this strategy using such functionalized ligands for the preparation of 2D (as schematized below) and 3D M’MOFs.[5] The synthesis, structure and characterization (porosity, optical properties) of these architectures will be presented.

pybpy)6].10(NO3).[2] These complexes have a 3D coordination polymer structure consisting of vertex-sharing prisms with chelating M(bpy)3 fragments at the vertices, and soc topology (shown below). Heteroleptic Zn(II) coordination polymers featuring both 4-pybpy and one of a range of bridging bis-carboxylate ligands only show Zn(II) coordination by the pyridyl group of the 4-pybpy ligand. For example, complex [Zn(4-pybpy)(isophthalate)] has an unprecedented selfcatenating network structure of {85.10} topology and free chelating sites lining large 1D channels. Copper cations can be doped into these sites in a single-crystal to single-crystal post synthetic modification.[3] The isomeric ligand N,N′-bis(pyridin-5-yl)-2,2′-bipyridine-5,5′dicarboxamide (5-pybpy), on the other hand, forms a discrete rather than polymeric complex, in the spherical [Pd12(5-pyby)12]24+ cage-like species which exists both in solution and the solid state. These and other examples will be discussed.

[Cu5(4-pybpy)6].10(NO3)

Strategy for the construction of a dipyrrin based 2D M’MOF. [1] (a) Chem. Rev. 2012, 112(2), 2012 Metal-Organic Frameworks issue . (b) Chem. Soc. Rev., 2009, 38, themed issue on MOFs. [2] (a) S. A. Baudron, CrystEngComm., 2010, 12, 2288-2295. (b) A. D. Burrows, CrystEngComm., 2011, 13, 3623-3642. (c) M. C. Das, S. Xiang, Z. Zhang, B. Chen, Angew. Chem. Int. Ed., 2011, 50, 10510-10520. [3] T. E. Wood, A. Thompson, Chem. Rev., 2007, 107, 1831-1861. [4] S. R. Halper, L. Do, J. R. Stork, S. M. Cohen, J. Am. Chem. Soc., 2006, 128, 15255-15268. [5] (a) D. Salazar-Mendoza, S. A. Baudron, M. W. Hosseini, Chem. Commun. 2007, 2252-2254. (b) D. Pogozhev, S. A. Baudron, M. W. Hosseini, Inorg. Chem., 2010, 49, 331-339. (c) C. Bronner, S. A. Baudron, M. W. Hosseini, Inorg. Chem., 2010, 49, 8659-8661. (d) B. Kilduff, D. Pogozhev, S. A. Baudron, M. W. Hosseini, Inorg. Chem., 2010, 49, 11231-11239. (e) A. Béziau, S. A. Baudron, M. W. Hosseini, Dalton Trans. 2012, 41, 7227-7234.

Keywords: Metal-Organic Frameworks, Heterometallic, Dipyrrin ligands

MS.A3.C.04 Metal-Organic Frameworks with 2,2’-bpy Ligands and PostSynthetic Metal Up-Take Michaele J. Hardie, Tia Jacobs, Elizabeth Lees, School of Chemistry, University of Leeds, Leeds (UK). E-mail: [email protected] The use of functionalised 2,2’-bipyridine ligands for the synthesis of coordination polymers has largely focused on carboxylic acid functionalised ligands.[1] We have developed a range of functionalised 2,2’-bipyridine ligands with N-donor and/or carboxylate functionality, that have generated a number of unusual and novel coordination polymer topologies. For example, ligand N,N′-bis(pyridin-4-yl)-2,2′bipyridine-5,5′-dicarboxamide (4-pybpy) forms complexes [M5(4-

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[Zn(4-pybpy)(isophthalate)] [1] for example P. Kruger et al, Chem. Commun. 2004, 776; J. R. Long, O. M. Yaghi, et al J. Am. Chem. Soc. 2010, 132, 14382; W. Lin et al, J. Am. Chem. Soc. 2010, 132, 12767.[2] T. Jacobs, M. J. Hardie, Chem. Eur. J., 2012, 18, 267. [3] T. Jacobs, R. Clowes, A. I. Cooper, M. J. Hardie, Angew. Chem. Int. Ed., 2012, DOI:10.1002/anie.201200758

Keywords: metal-organic framework, post-synthetic modification, self-catenating

MS.A3.C.05 Supramolecular Crystal Chemistry with Porphyrin Tinkertoys Israel Goldberg, School of Chemistry, Sackler Faculty of Exact Sciences, Tel-Aviv University, 69978 Ramat-Aviv, Israel. E-mail: [email protected] This presentation addresses the scientific challenge of predictably self-organizing porphyrin molecules into materials with complex topologies, with an emphasis on rational construction of open framework solids (metal-organic frameworks) and systems exhibiting

Microsymposia

[1] I. Goldberg, Chem. Commun. 2005, 1243-1254; and CrystEngComm 2008, 10, 637-645. [2] S. Lipstman; I. Goldberg, Cryst. Growth Des. 2010, 10, 1823-1832, 4596-4606, and 5001-5006. [3] A. Karmakar, I. Goldberg, CrystEngComm 2010, 12, 4095-4100. [4] H. M. Titi, A. Karmakar, I. Goldberg, J. Porphyrins Phthalocyanines 2011, 15, 1250-1257.

Keywords: porphyrin assemblies, metal-organic frameworks, supramolecular chirality

MS.A3.C.06 Enhanced Stability in Peptide-Based Porous Materials Carlos Martí-Gastaldo, John E. Warren, Matthew J. Rosseinsky, Department of Chemistry, University of Liverpool, Liverpool, (UK). E-mail: [email protected] The development of open frameworks by introduction of biologically derived molecules as organic linkers is attracting particular attention nowadays. To date, the incorporation of amino acids or nucleobases has proven a valid route towards the design of bio-analogous MOFs. These hybrid biomaterials combine the intrinsic MOF characteristics with the metal-binding versatility, structural flexibility, homochirality, stereochemical selectivity or biological compatibility provided by the bio-backbone.[1] In this context, the use of oligopeptides has recently led to unprecedented adaptable porosity of the host upon gas sorption in [Zn(Gly-Ala)2].[2] The flexibility of the peptide linker plays a key role in adapting the pore conformation as the multiple torsions available to polypeptide chains results in a wide distribution of combined torsional degrees of freedom, which permit the framework to adopt a wider energy landscape of thermally accessible conformations. We have recently isolated [Zn(Gly-Thr)2] by substitution of gycylalanine (Gly-Ala) with glycilthreonine (Gly-Thr), hence confirming that the synthetic versatility generally attributed to MOF

chemistry can be also associated to these peptidic coordination polymers.[3] Besides exhibiting selective adsorption of CO2 over CH4, this 2D layered framework with 1D porosity remains crystalline upon solvent removal as confirmed by the single-crystal structural studies of the material before and after evacuation. This scenario contrasts with the poor structural stability generally attributed to peptide-based materials. We will show how the compromise between flexibility and structural stability can be achieved via precise control of the coordination modes and supramolecular interactions enabled by the peptide hence opening the door for the design of a next generation of robust adaptable porous materials.

[1] I. Imaz, M. Rubio-Martínez, J. An, I. Solé-Font, N. L. Rosi, D. Maspoch, Chem. Commun. 2011, 1. [2] J. Rabone, Y. F. Yue, S. Chong, K. Stylianou, J. Bacsa, D. Bradshaw, G. Darling, N. Berry, Y. Khimyak, A. Ganin, P. Wiper, J. B. Claridge, M. J. Rosseinsky, Science 2010, 329, 1053. [3] C.Martí-Gastaldo, J. E. Warren, K. C. Stylianou, N. L. O. Flack, M. J. Rosseinsky (submitted).

Keywords: metal-organic frameworks, peptides, adaptable porosity

MS.A3.C.07 Functional Studies of Dynamic and Rigid Porous Coordination Polymers Sujit K. Ghosh, Department of Chemistry, IISER Pune, (Spain). E-mail: [email protected] Metal-Organic Frameworks (MOFs) or Porous coordination polymers (PCPs) have attracted much attention due to scientific interest in the creation of nanometer-sized spaces and for their potential application in molecular sieves, gas storage and heterogeneous catalysis. With extra large porosity, pore shape and size modulation, pore surface functionalization and framework flexibility are also considered to be one of the key factors for the next generation of PCPs. Among many other current challenges, effective capture of carbon dioxide from industrial flue gases has become one of the most pressing issues concerning environmental conservation and protection because CO2 is the predominant greenhouse gas causing global warming. Also chemical separation is very important in industry. In this presentation several novel rigid and dynamic MOFs s and their functional properties will be discussed to address those important challenges.

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supramolecular chirality. In order to achieve these goals, the porphyrin scaffold is functionalised with different molecular recognition groups prone to engage in robust supramolecular synthons. This allows us to reasonably control the self-assembly process and to alter systematically the composition, topology, porosity and functionality of the supramolecular arrays that form. The crystal-engineering approach represents an attractive “bottom-up” strategy to tailoring ordered lattice materials, achiral and chiral network architectures, as well as organic zeolite-type analogues. In the above context, the tetra(3/4-pyridyl)porphyrin (TPyP) and tetra(3/4-carboxyphenyl)porphyrin (TCPP) compounds have played a key role in the construction of diverse polymeric architectures [1]. They are characterized by rigid square-planar geometry, bear multiple diverging molecular recognition sites (tetradentate functionality) for metal coordination as well as hydrogen/halogen-bonding, and consequently reveal an extraordinarily rich supramolecular chemistry. Of particular interest is the coordination polymerization of these scaffolds through exocyclic metal ion connectors, which often results in the formation of robust porous architectures (framework coordination polymers). Construction of homo-molecular as well as hetero-molecular assemblies sustained strictly by cooperative hydrogen bonding has been also demonstrated [1, 2]. Another subject of major interest relates to supramolecular chirality, which involves chiral arrangement of achiral molecular components in a non-covalent assembly. Successful induction of supramolecular chirality has been achieved with asymmetrically substituted (either in a lateral or an axial direction) porphyrin building blocks, using either hydrogen or halogen bonds (I/Br···N, [3,4]) as directors of the intermolecular organization. Representative structure types will be described.

Microsymposia

[1] B. Joarder, A. K. Chaudhari, and S. K. Ghosh, Inorg. Chem., 2012, 51, 46444649. [2] S. S. Nagarkar, A. K. Chaudhari, and S. K. Ghosh, Inorg. Chem. 2012, 51, 572-576. [3] S. K. Ghosh, W. Kaneko, D. Kiriya, M. Ohba, S. Kitagawa, Angew. Chem. Int. Ed. 2008, 47, 8843-8847. [4] S. K. Ghosh, J.-P. Zhang, S. Kitagawa, Angew. Chem. Int. Ed. 2007, 46, 7965-7968.

Keywords: Porous materials, Adsorption, Separation

MS.A3.C.08 Alkaline-Earth Metal Organic Frameworks. New topologies for heterogeneous catalysts Enrique Gutiérrez-Puebla, Ana E. Platero-Prats, Marta Iglesias, Natalia Snejko, Ángeles Monge, Instituto de Ciencia de Materiales de Madrid, Madrid, Spain. E-mail: [email protected] The current environmental needs, which are becoming more and more considered in chemistry research, have posed new scientific challenges in catalysis. In this sense, alkaline-earth MOFs (AE-MOFs) could represent a comparatively cheap, nontoxic, and green alternative to conventional heterogeneous catalyst. However, the synthesis of AE-MOFs still remains much less explored, mainly due to the inherent difficulties arising from these elements (their unpredictable coordination numbers and geometries or the formation of solvated species) [1], Recent efforts made in such a way have given rise to exciting AE-MOFs with good performances in gas/liquid separations [2] or heterogeneous catalysis [3], proving the viability of this green alternative. We are engaged in the preparation of new Alkaline-Earth Polymeric Frameworks (AEPF) using flexible ligands, where the use of a flexible dicarboxylate ligands. As a result of these synthesis, new robust AE-MOFs have been constructed, they belong to different 2D and 3D structural types, and their topologies have been analyzed [4] . The catalytic behaviour of these alkaline-earth materials was also investigated in reactions of hydrogenation of alkenes and hydrosilylation of carbonyls and alkenes under mild conditions using styrene, benzaldehyde, and acetophenone, as substrates. The good catalytic results obtained using these robust AE-MOFs as heterogeneous catalysts have proved that unsaturated AE ions in MOFs can act as Lewis acid active sites for hydrogenation of alkenes, shedding light on the use of cheap MOFs in catalysis.

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Figure Kinetic profiles of styrene hydrogenation using Sr-AEPF-13 as catalyst (at different temperatures, 5 atm H2, using 1 mol% [1] D. Banerjee, et al. Cryst. Growth Des., 2011, 11, 2572. [3] A.E. PlateroPrats et al. Chem.-Eur. J., 2010, 16, 11632. [2] A.E. Platero-Prats et al. ChemCatChem, 2010, 2, 147, and Cryst. Growth Des. 2011, 11, 1750. [4] A.E. Platero-Prats et al. J. Am. Chem. Soc., 2012, 4762.

Keywords: dynamic porous materials, metal–organic frameworks, heterogeneous catalysis

MS.A3.C.09 Strategies Towards Porous Iron(III) Metal Organic Frameworks Hubert Chevreau,a Thomas Devic,a Patricia Horcajada,a Fabrice Salles,b Guillaume Maurin,b Norbert Stock,c Christian Serre,a a Institut Lavoisier, Université de Versailles Saint Quentin en Yvelines, Versailles (France). bInstitut Charles Gerhardt, Montpellier (France). cChristian Albrechts Universität, Kiel (German). E-mail: hubert.chevreau@ chimie.uvsq.fr Metal Organic Frameworks (MOFs) are crystalline coordination polymers built up from inorganic units connected through polytopic ligands (typically carboxylate) to define pores of various size and shape [1]. Iron(III) is a very interesting constituent due to its low cost, low toxicity and redox-activity. If iron(III) reacts easily with carboxylatetype ligands, its strong acidic character leads either to precipitation of hydroxides or fast nucleation processes, which makes structure determination from single crystals scarce. Thus, only a limited number of porous iron(III) MOFs have been reported so far [2]. We report here our recent results on the synthesis and characterization of new Fe(III) MOFs, all based on oxo-centred trimers of FeO6 octahedra (Figure 1a). Three approaches which are interpenetration, isostructurality and isoreticularity have been applied and have successfully led to three porous iron(III) MOFs. MIL-126 is based on 4,4’-biphenyldicarboxylate and consists of two interwoven networks of the highly flexible MIL88D type, this interpenetration ensuring both rigidity and permanent porosity (Figure 1b) [3]; MIL-127 is based on 4,4’-azobenzenetetracarboxylate and is isostructural to soc MOF (Figure 1c); [4] MIL100btb (btb=1,3,5-Tris(4-carboxyphenyl)benzene) is isoreticular to MIL-100, a mesoporous zeotype material (topology MTN) but built up from larger hybrid super-tetrahedra (Figure 1d) [5]. In order to discover news structures, an alternative strategy consists of using mixtures of two different ligands. From a same mixture of iron(III), terephthalic and btb acids, two novel MOFs have been synthesized: MIL-142, which is a microporous interwoven solid built up from hybrid super-octahedra (Figure 1e) and MIL-143, a mesoporous solid which consists on an alternation of super-tetrahedra identical to those exhibited in MIL-100 [5] and MIL-101 [6]. (Figure 1f)

Microsymposia

Figure 1: (a) iron(III) trimers. (b) MIL-126. (c) MIL-127. (d) Super-tetrahedra of MIL-100btb. (e) MIL-142. (f) MIL-143.

Keywords: Coordination Polymers, Iron, Porous Solids

[1] O. M. Yaghi, M. O’Keeffe, N. W. Ockwig, H. K. Chae, M. Eddaoudi, J. Kim, Nature, 2003, 423, 705; G. Ferey, Chem. Soc. Rev., 2008, 37, 191. [2] R. S. Crees, M. L. Cole, L. R. Hanton, C. J. Sumby, Inorg. Chem., 2010; 49, 1712.

Keywords: metal-organic frameworks, azolium ligands, gas separation

MS.A3.C.10 The Chemistry of Azolium–Containing Metal-Organic Frameworks Christopher J. Sumby,a Alexandre Burgun,a Marcus L. Cole,b Rachel S. Crees,a Christian J. Doonan,a aSchool of Chemistry & Physics, University of Adelaide, Adelaide, (Australia). bSchool of Chemistry, University of New South Wales, Sydney (Australia). E-mail: christopher. [email protected] Metal-organic frameworks (MOFs) are a class of highly porous, crystalline materials that can be synthesised from metal ions or metaloxide joints and organic links. [1] Such materials show promise as physisorbents for gas separations (e.g. CO2/N2), and for ‘heterogenising’ existing homogenous catalysts, for example. By carefully modifying the organic links that are incorporated into a particular MOF, the properties of the material can be changed. Another way to alter the properties of a MOF is to decoratate the framework with metal ions in a non-structural role. These modifications may result in enhanced selectivity for a particular gas, such as CO2, or allow the inclusion of a catalytic moiety into the framework. We have been investigating the synthesis and properties of MOFs that contain azolium moieties within (integrated) or appended (pendant) to the link (Figure 1a). We have synthesised a number of novel materials containing integrated imidazolium based links, including one which can be selectively decorated with metal ions in a non-structure defining role during synthesis, [2] and a second, with a previously unobserved joint (secondary building unit), that forms a four-fold interpenetrated diamondoid structure with ~11.5 Å diameter channels (Figure 1b). In this second example the Cu(I) centres play a structure defining role and the same, non-metallated structure is not observed. We have also been investigating other N-heterocyclic carbene precursors as links for MOFs. The synthesis and the gas adsorption and separation potential of various framework materials, formed from azolium containing links, will be discussed.

MS.A3.C.11 One-Dimensional Chains of Ru, Rh and Ag Matti Haukka,a aUniversity of Eastern Finland, Joensuu, Finland. E-mail: [email protected] Linear 1D transition metal chains have attracted attention because of their magnetic, photophysical, conductive, and catalytic properties. In multinuclear metal compounds or assemblies of metal complexes the constructive interplay between the metal centers can generate properties than don’t exist in mononuclear metal compounds. Changes in photophysical, optical, catalytic, and conductive properties may all be obtained by adjusting the metal-metal distances or contacts between the metal complexes. In materials where the arrays of metal centers are spatially uniformly oriented, anisotropic behavior may also arise. Anisotropic behavior is emphasized especially in systems consisting of linear, one-dimensional chains of metals. One of the most straightforward way to build linear structures is to assemble square planar complexes into a chain-like stacks. Mononuclear cationic rhodium complexes such as [Rh(L)(CO)2]+ (L = 2,2’-biimidazole, 2,2’-bipyridine, or 1,10-phenantrholine) all form cationic onedimensional chains in solid state.[1] The Rh-Rh distances and the photophysical properties of the stacks can be effectively modified by varying the counter anions and solvents of crystallization. The neutral dinuclear [Rh2(R2bim)Cl2(CO)4] units (R2bim = N,N’-diethyl2,2’-biimidazole or N,N’-dimethyl-2,2’-biimidazole) form neutral chains with strongly anisotropic optical properties.[2] Neutral chain structures consisting of alternating cationic and anionic square planar Rh complexes are rare but can be obtained via reductive carbonylation of RhCl3 in the presence of 2,2’-bipyridine or 1,10’phenathroline. The chains consist of cationic [Rh(L)(CO)2]+ (L = 2,2’-bipyridine or 1,10-phenatrholine) and anionic [RhCl2(CO)2]- units.[3] Another method to construct linear chain structure is to use supporting multidentate ligands to bring metal centers together. Imidazole groups containing Schiff bases such as 1,3-bis[(1-methyl2-imidazolyl)-methyleneamino]propane provide a suitable supporting ligands for building linear silver compounds.[4] Just like covalent bonds, non-covalent interactions such as

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[1] Chem. Rev. 2012, 112, 673. [2] A. Fateeva and al. Chem. Mater. 2011, 23, 4641. [3] M. Dan-Hardi and al. Chem. Mat. 2012, submitted. [4] Y. Liu and al. Angew. Chem., Int. Ed. 2007, 46, 3278. [5] G. Férey and al. Angew. Chem., Int. Ed. 2004, 43, 6296. [6] G. Férey and al. Science, 2005, 309, 2040.

Microsymposia halogen bonds can be used for building functional extended molecular structures. For example, assemblies of Ru complexes [Ru(4,4’-R2-L) (CO)2X2] (L = 2,2’bipyridine, R = H or COOH, X = Cl, Br, or I) can be built via halogen bonds using simple I2 linkers.[5] [1] E. Laurila, L. Oresmaa, M. Niskanen, P. Hirva, M. Haukka, Cryst. Growth Des. 2010, 10, 3775. [2] E. Laurila, R. Tatikonda, L. Oresmaa, P. Hirva, M. Haukka, submitted for publication. [3] E. Laurila, Oresmaa, J. Hassinen, P. Hirva, M. Haukka, submitted for publication. [4] L. Koskinen, S. Jääskeläinen, L. Oresmaa, M. Haukka, CrystEngComm 2012, 14, 3509. [5] M. Tuikka, M. Niskanen, P. Hirva, K. RIssanen, A. Valkonen, M. Haukka, Chem. Commun. 2011, 47, 3427. Keywords: transition metals, one-dimensional chains, metal-metal interactions

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Microsymposia

Combining Multiple Functions within Metal-Organic Framework Materials Cameron Kepert, School of Chemistry, University of Sydney, Sydney, (Australia). E-mail: [email protected] Over recent years the design and synthesis of molecular materials has seen the emergence of a range of interesting and potentially useful host-guest, electronic, magnetic and mechanical properties. These include: Nanoporosity - the linkage of metal ions with multitopic ligands has generated robust open lattices that are able to act as hosts for a wide range of molecular guests; Electronic Switching - the incorporation of spin crossover centres into nanoporous molecular frameworks has led to the first porous materials that can be switched between multiple electronic states; and Negative Thermal Expansion (NTE, ie, contraction with heating) - unprecedented NTE behaviour associated with the thermal population of low energy transverse phonons has been observed in a broad family of coordination frameworks. Here we examine the various forms of interplay between these three properties, with particular focus on the influence of guestexchange on electronic and thermomechanical properties, the influence of electronic transitions on guest adsorption properties, and the use of electronic transitions to promote unprecedented thermal expansion behaviours. Keywords: porosity, spin crossover, thermal expansion

MS.A4.I1 Quantum Molecular Spintronics Based on Single-Molecule Magnets Masahiro Yamashita, Department of Chemistry, Tohoku University, Sendai, Japan. E-mail: [email protected] Spintronics is a key technology in 21st century based on the freedoms of the charge, spin, as well as orbital of the electron. The MRAM systems (magnetic random access memory) by using GMR, CMR or TMR have several advantages such as no volatility of information, the high operation speed of nanoseconds, the high information memory storage density, and the low consuming electric power. Usually in these systems, the bulk magnets composed of the transition metal ions or conventional magnets are used, while in our study we will use Single-Molecule Quantum Magnets (SMMs), which are composed of multi-nuclear metal complexes and nano-size magnets. Moreover, SMMs show the slow magnetic relaxations with the double-well potential defined as |D|S2 and the quantum tunneling. Although the bulk magnets are used in conventional spintronics with the largest spin quantum number of 5/2 for example, we can create the artificial spin quantum numbers of 10, 20, 30, etc. in SMMs. Then, we can realize the new quantum molecular spintronics by using SMMs. According to such a strategy, we have synthesized the conducting SMM such as [Pc2Tb]Cl0.6, whose blocking temperature is 47K. The hysteresis is observed below 10K. This conducting SMM shows the negative magnetoresistance below 8 K. As for the second strategy, we have a plane of the input and output of one memory in double-decker Tb(III) SMM (Pc2Tb) by using the spin polarized STM (Scanning Tunneling Microscopy). In this research, we have observed Kondo Effect at 4.8 K by using STS (Scanning Tunneling Spectroscopy) for the first time. We have succeeded in controlling the appearance and disappearance of Kondo Peak by the electron injection using STS, reversibly. This is considered as the first single-molecule memory device.[1] As for the third strategy, we have made the FET (Field Effect

Transistor) devices of SMMs. The Pc2Dy device shows the ambipolar (n- and p-type) behavior, while the Pc2Tb device shows the p-type behavior. Such a difference is explained by the energy levels of the lanthanide ions.2 [1] T. Komeda, M. Yamashita, et al., Nature Commun., 2, 217 (2011).

Keywords: Molecular Spintronics, Single-Molecule Magnets, Kondo Effect

MS.A4.I2 Helical (Supramolecular) Chirality in Tetrathiafulvalenes Derivatives Narcis Avarvari, University of Angers, CNRS Laboratoire MOLTECHAnjou, Angers, (France). E-mail: [email protected] Introduction of chirality into conducting systems is a topic of much current interest as it allows the preparation of multifunctional materials in which the chirality might modulate the structural disorder or expresses its influence through the electrical magneto-chiral anisotropy effect. The access to various chiral electroactive precursors for molecular conductors is therefore of paramount importance [1]. We have recently developed two new families of TTFs in which the chiral information is expressed in different ways. A first series is based on a C3 symmetric core decorated with three TTF-amidobipyridine fragments, which show self-assembling properties. One of the compounds provided for example an electroactive organogel and conducting nanowires [2]. Moreover, when substituted with chiral alkyl chains, these compounds show hierarchical chiral expression at nano- and mesoscale in solution and solid state [3],[4]. Indeed, supramolecular chirality expressed through the formation of helical fibres of nano- or meso-scopic size following hierarchical self-assembly processes is a topic of great current interest in diverse scientific fields.

C3-symmetric tris-TTFs providing helical aggregates.

A second family of chiral TTFs we will discuss present helical chirality provided by helicene units fused with the TTF moiety. [1] N. Avarvari, J. D. Wallis, J. Mater. Chem. 2009, 19, 4061-4076. [2] I. Danila, F. Riobé, J. Puigmartí-Luis, Á. Pérez del Pino, J. D. Wallis, D. B. Amabilino, N. Avarvari, J. Mater. Chem. 2009, 19, 4495-4504. [3] I. Danila, F. Riobé, F. Piron, J. Puigmartí-Luis, J. D. Wallis, M. Linares, H. Ågren, D. Beljonne, D. B. Amabilino, N. Avarvari, J. Am. Chem. Soc., 2011, 133, 8344-8353. [4] I. Danila, F. Piron, C. Escudero, L. N. Feldborg, J. Puigmartí-Luis, F. Riobé, N. Avarvari, D. B. Amabilino, Chem. Commun., 2012, in press.

Keywords: molecular conductors, chirality, supramolecular chemistry

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MS.A4.KN1

Microsymposia MS.A4.C.01 SMM and Luminescence in Ln(III) complexes based on redox active TTF derivatives Lahcène Ouahab, Fabrice Pointillart, Olivier Cador, Stéphane Golhen, Institut des Sciences Chimiques de Rennes, UMR 6226 CNRSUniversité de Rennes 1, 35042, Rennes Cedex, (France). E-mail: [email protected] Since the discovery of TTF in early 1973, many interesting materials have been obtained as organic metals, semi-conductors, superconductors, magnets, and so on. In the last decade, TTF derivatives have been associated to d metal ions to elaborate multifunctional materials which possess magnetic and electrical properties. The 4f lanthanides exhibit exiting specific luminescent properties. In particular, lanthanide complexes with b-diketones have focused a large attention due to their potential applications in the design of chelate lasers, efficient organic and polymer light emitting diodes (OLEDs and PLEDs). The irradiation of the [Yb(hfac)3(TTF-CONH-2-Py-N-oxide)2] compound in the HOMO®LUMO+1/+2 charge transfer bands provokes the emission of both donor and Yb(III) ion. We have shown that the donor is an efficient organic antenna for the sensitization of Yb(III) luminescence in solid state [1]. Similar luminescence property and antenna effect have been observed in solution for the Er(III) ion in the [Er(hfac)3(TTF-4-Pybiester)] compound [2]. Lanthanide ions are also well-known to exhibit strong magnetic anisotropy and therefor they are considered as good candidates for the elaboration of Single Molecule Magnets (SMM). We have associated the tetrathiafulvalene-3-Pyridine-N-oxide ligand to the Ising Dy(III) ions producing a centrosymmetric dinuclear complex in which the magnetic moments are antiferromagnetically coupled. Surprisingly, the complex behaves as a SMM with both strong frequency dependent out-of-phase signal of the ac magnetic susceptibility and magnetization loop [3] A new Single Ion Magnet (SIM) has been also recently discovered in the Dy(III) dimers containing an Acceptor-DonorAcceptor bridging ligand [4]. [1] F. Pointillart, T. Cauchy, O. Maury, Y. Le Gal, S. Golhen, O. Cador, L. Ouahab, Chem. Eur. J. 2010, 16, 11926. [2] F. Pointillart, A. Bourdolle, T. Cauchy, O. Maury, Y. Le Gal, S. Golhen, O. Cador, L. Ouahab, Inorg Chem. 2012, 49, 978. [3] F. Pointillart, Y. Le Gal, S. Golhen, O. Cador, L. Ouahab, Chem. Eur, 2011, 17, 10397 [4] F. Pointillart, S. Klementieva,V. Kuropatov, Y. Le Gal, S. Golhen, O. Cador, V. Cherkasov, L. Ouahab, JCS Chem Commun., 2012, 48(5), 714.

Keywords: SMM, Luminescence, redox ligands

MS.A4.C.02 Control of Charge-Transfer in Donor/Acceptor-MOFs Hitoshi Miyasaka, Department of Chemistry, Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan). E-mail: [email protected]. Metal-organic frameworks (MOFs) comprised of electron-donors (D) and –acceptors (A), i.e. D/A-MOFs, are intriguing candidates toward magnetic, conducting, and their synergistic materials, because the charge transfer (CT) of D0A0 → Dd+Ad– in MOFs is not only involves an electron transfer from D to A, but also generates a new spin set of S = ½ spins with an exchange interaction. The D:A = 2:1 (or 1:2) system, which allows to construct multi-dimensional MOFs as ladder, 2D, and 3D networks, is the most fascinating target because this formula can possibly create a mixed-valence network system with

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one-electron transfer [1-9]. Although the D:A = 1:1 system, which is possible to form 1D chains, is only producible either neutral (N) or ionic state (I) in the limited case, its partial CT systems like Dd+Ad- or systems that occur N-I transitions dependent on external modulations (such as T and P) are also favorable cases [10]. Covalent-bonded assemblies of paddlewheel diruthenium (II, II) complexes [Ru2II,II] and TCNQ/DCNQI demonstrate such materials [1-10], in which both magnetic and conducting properties are tuned by intra-lattice CTs [11]. [1] H. Miyasaka, C. S. Campos-Fernández, R. Clérac, K. R. Dunbar, Angew. Chem. Int. Ed. 2000, 39, 3831. [2] H. Miyasaka, T. Izawa, N. Takahashi, M. Yamashita, K. R. Dunbar, J. Am. Chem. Soc. 2006, 128, 11358. [3] N. Motokawa, T. Oyama, S. Matsunaga, H. Miyasaka, K. Sugimoto, M. Yamashita, N. Lopez, K. R. Dunbar, Dalton Trans. 2008, 4099. [4] N. Motokawa, H. Miyasaka, M. Yamashita, K. R. Dunbar, Angew. Chem. Int. Ed. 2008, 47, 7760. [5] N. Motokawa, T. Oyama, S. Matsunaga, H. Miyasaka, M. Yamashita, K. R. Dunbar, CrystEngComm 2009, 11, 2121. [6] H. Miyasaka, N. Motokawa, S. Matsunaga, M. Yamashita, K. Sugimoto, T. Mori, N. Toyota, K. R. Dunbar, J. Am. Chem. Soc. 2010, 132, 1532. [7] N. Motokawa, H. Miyasaka, M. Yamashita, Dalton Trans. 2010, 39, 4724. [8] N. Motokawa, S. Matsunaga, S. Takaishi, H. Miyasaka, M. Yamashita, K. R. Dunbar, J. Am. Chem. Soc. 2010, 132, 11943. [9] H. Miyasaka, T. Morita, M. Yamashita, Chem. Commun. 2011, 47, 271. [10] H. Miyasaka, N. Motokawa, T. Chiyo, M. Takemura, M. Yamashita, H. Sagayama, T. Arima, J. Am. Chem. Soc. 2011, 133, 5338. [11] K. Nakabayashi, M. Nishio, K. Kubo, W. Kosaka, H. Miyasaka, Dalton Trans. 2012, DOI:10.1039/C2DT30365E.

Keywords: Charge-transfer, Donor/acceptor-MOFs, Magnetism

MS.A4.C.03 Light-insensitive Silver(I) Cyanoximates: Properties and Remarkable Applications Nikolay Gerasimchuk, Department of Chemistry, Missouri State University, Springfield (USA). E-mail: NNGerasimchuk@ MissouriState.edu Cyanoximes represent a new interesting class of ampolydentate acidoligands that have NC-C(=NOH)-R general formula, where R is an electron-withdrawing group [1-3]. The reaction between AgNO3 and a series of cyanoximes HL (shown below together with their commonly used abbreviations) in the presence of base at ambient conditions leads to sparingly soluble, colored complexes of AgL composition. All ten AgL complexes were characterized using IR-/Raman, UVvisible spectroscopy and X-ray analysis. Obtained compounds are 2D-coordination polymers of different complexity in which cyanoxime anions act as bridging ligands. Compounds demonstrate extraordinary, for many years stability towards visible light. There are three areas of potential practical applications of these unusual complexes: a) battery-less area detectors of UV-radiation [4]; b) non electrical sensors for gases of industrial importance such as H2, C2H2, C2H4, NO, SO2, NH3 [5]; and c) antimicrobial additives to the light-curable acrylate polymeric fillers and adhesives used during introduction of indwelling medical devices [6]. Chemical, technological and biological aspects of these applications are discussed in details.

Microsymposia

Figure 1. Crystal structure of 1.

Figure 2. χMT vs. T plot for 1.

[1] M. Mitsumi et al., Angew. Chem. Int. Ed. 2005, 44, 4164–4168.

Keywords: silver(I), polymers, cyanoximes

MS.A4.C.04 Multifunctional Materials: Conductivity and Ferromagnetic Coupling in 1-D Rh–Dioxolene Minoru Mitsumi, Masahiro Hashimoto, Koshiro Toriumi, Graduate School of Material Science, University of Hyogo, Hyogo (Japan). E-mail: [email protected] The development of multifunctional molecular materials exhibiting the interplay between the physical properties such as conducting, magnetic, and optical, is one of the major subjects of material science. To realize such a multifunctionality, we are studying for the frontier orbital control of the metal d and semiquinonate ligand π* orbitals in the rhodium(I)–semiquinonato complex. When the energy level of ligand π* orbital could be adjusted to be the same as that of the 1-D d band by introducing of electron-withdrawing substituent or by applying pressure, the rhodium(I,II)–semiquinonato/catecholato mixed-valence state will be achieved by the intramolecular charge transfer between metal and ligand. Along this line, we have succeeded in developing the rhodium(I,II)–semiquinonato/catecholato mixed-valence compound [Rh(3,6-DBDiox-4,5-Cl2)(CO)2]∞ (3,6-DBDiox-4,5-Cl2 = 3,6-di-tertbutyl-4,5-dichloro-1,2-benzosemiquinonato or 3,6-di-tert-butyl-4,5dichlorocatecholato), which shows semiconducting behavior with significant electrical conductivity at room temperature (σRT = 17–34 S cm–1).[1] We focus our efforts towards the development of the multifunctional molecular materials exhibiting metallic conductivity and ferromagnetism. We report the crystal structure and solid-state properties of a onedimensional rhodium(I)–semiquinonato complex [Rh(3,6-DBSQ-4NO2)(CO)2]∞ (1) (3,6-DBSQ-4-NO2– = 3,6-di-tert-butyl-4-nitro-1,2benzosemiquinonato), in addition to our recent efforts in developing the multifunctional molecular materials. The compound 1 forms the one-dimensional (1-D) chain structure by strong Rh–Rh interactions. The χMT value at 300 K is about two thirds of the spin only value of S = 1/2 but show a sudden increase around 200 K and then reaches to maximum with lowering the temperature. The observed increase in χMT indicates that ferromagnetic interaction operates between the spins in the 1-D chain. Conducting property of 1 will be also discussed.

MS.A4.C.05 Bisdithiolene Complexes Based on Extended TTF-Derivatives Bearing Pyridine Rings Sandra I.G. Dias,a Joana T. Coutinho,a Ana I.S. Neves,a Laura C.J. Pereira,a Isabel C. Santos,a Sandra Rabaça,a John D. Wallis,b Manuel Almeida,a aDept. de Química, Instituto Tecnológico e Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa/CFMCUL, P-2686-953 Sacavém (Portugal). bSchool of Science and Technology, The Nottigham Trent University, Clifton Lane, Nottingham (UK). E-mail: [email protected] Transition metal bisdithiolene complexes with extended tetrathiafulvalene (TTF) based ligands have attracted increasing interest due to their extended p-conjugated system and the possibility of displaying higher electrical conductivity properties.[1] And indeed, when oxidized to the neutral state some of them have been in the base of several single component molecular metals.[2] On the other hand, the attachment of functional groups, capable of coordination with transition metals, to the central core of the donor framework has also attracted considerable attention recently, making it possible to achieve more intricate coordination structures and multifunctional materials. We will present our work on the synthesis and characterization of new divalent thio-azo donor ligands containing both pyridine rings and extended p-systems with TTF moieties. These TTFsubstituted ligands, have been synthetized by coupling reaction of the corresponding 1,3-dithiole-2-ones and have the ability to coordinate with transition metals through the nitrogen atom of the pyridine ring. [3] The S-coordination ability of these ligands to several metals (M= Au, Ni, …) is demonstrated by the preparation of monoanionic complexes which have been isolated and characterized.[4] X-ray analysis, cyclic voltammetry and magnetic studies of these complexes will be discussed.

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[1] A.A. Mokhir, K.V. Domasevich, Inorg. Chim. Acta, 1999, 284, 85. [2] D. Robertson, J. F. Cannon, N. Gerasimchuk. Inorg. Chem., 2005, 44 (23), 8326. [3] O.T. Ilkun, O.T.; S.J. Archibald, et al. Dalton Trans., 2008, 5715. [4] G. Glower, N. Gerasimchuk, et al. Inorg. Chem. 2009, 48 (6), 2371. [5] N. Gerasimchuk, N., A.N. Esaulenko. Dalton Trans. 2010, 39, 749. [6] N.Gerasimchuk, A. Gamian. Inorg. Chem.. 2010, 49 (21), 9863.

Keywords: multifunctional material, conductivity, ferromagnetic coupling

Microsymposia [1] L. Alcácer, H. Novais, in Extended Linear Chain Compounds, vol. 3, Plenum Press, New York, 1983, chapter 6, pp. 3192351; N. Robertson, L. Cronin, Coord. Chem. Rev., 2002, 227, 93-127. [2] H. Tanaka, Y. Okano, H. Kobayashi, W. Suzuki, A. Kobayashi, Science, 2001, 285-287; J.P. Nunes, M.J. Figueira, D. Belo, I.C. Santos, B. Ribeiro, E.B. Lopes, R.T. Henriques, J. VidalGancedo, J. Venciana, C. Rovira, M. Almeida, Chem. Eur. J., 2007, 9841-9849. [3] S.I.G. Dias, A.I.S. Neves, S. Rabaça, I.C. Santos, M. Almeida, Eur. J. Inorg. Chem., 2008, 4728-4734. [4] S.I.G. Dias, S. Rabaça, I.C. Santos, L.C.J. Pereira, R.T. Henriques, M. Almeida, Inorg. Chem. Commun., 2012, 102-105.

Keywords: TTF, bisdithiolene, pyridine

MS.A4.C-06 Dielectric Properties Associated with Molecular Motions in (anilinium) (benzo[18]crown-6) [MnIICrIII(oxalate)3]Ferromagnetic Complex Kazuya Kubo,a,b Toru Endo,b Shin-ichiro Noro,a,b Tomoyuki Akutagawa,c Sadamu Takeda,d Takayoshi Nakamura,a,b aResearch Institute for Electronic Science, Hokkaido Univ (Japan). bGraduate School of Environmental Science, Hokkaido Univ (Japan). cInstitute of Multidisciplinary Research for Advanced Materials Tohoku Univ (Japan). dGraduate School of Science, Hokkaido University (Japan). E-mail: [email protected] [Introduction] Previously, we reported molecular ferroelectric material, (m-fluoroanilinium+)(dibenzo[18]crown-6)[Ni(dmit)2]-, based on a supramolecular structure exhibiting molecular rotation. [1] In this work, we synthesized (anilinium+)(benzo[18]crown-6) [MnIICrIII(oxalate)3]- (1) and deuterated complex, (anilinium-d5+) (benzo[18]crown-6)- [MnIICrIII(oxalate)3]- (2). Salt 1 exhibited a relatively large dielectric response and a ferromagnetic behevior arising from the supramolecular cation and [MnIICrIII(oxalate)3]moiety, respectively. Origin of the dielectric response was investigated by solid state 2H-NMR. [Result] Figure 1 shows the crystal structures of 1. One supramolecular canion and [MnIICrIII(oxalate)3]- unit was crystallographically independent. The [MnIICrIII(oxalate)3]- layers formed two dimensional honeycomb structure. Between the anionic layers, supramolecular cations of (anilinium+)(benzo[18]crown-6) were located. In the magnetic measurements, ferromagnetic transition at 5 K was observed arising from ferromagnetic coupling in the [MnIICrIII(oxalate)3]- layers. Crystal 1 showed large dielectric responses in the low frequency regions above 340 K. The solid state 2H-NMR was measured on crystal 2. The dielectric responses originated from molecular motion will be discussed from the temperature dependence of line shape of 2H-NMR.

Figure 1. Crystal structure of 1.

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[1] T. Akutagawa et al. Nature Materials 8, 342-347 (2009).

Keywords: Supramolecular structure, Multiferroic material, Dielectric response, Magnetic susceptibility, Solid state NMR

9 - 13 September 2012

MS.B1.KN1 Extended Diketone, Triketone and Polypyridine Derivatives – Versatile Building Blocks for Metallo-Supramolecular Chemistry Leonard F. Lindoy, School of Chemistry, F11, The University of Sydney, NSW 2006 (Australia). E-mail:[email protected] We have employed ligand derivatives incorporating polypyridyl and β-diketonato ligand domains for the construction of a range of unusual supramolecular structures.[1]-[3]. For example, bis-βdiketonato derivatives in which the β-diketone fragments are linked via a 1,3- or 1,4-substituted aryl group, or by corresponding pyridyl, bipyridyl or biphenylene groups, have been employed to construct new neutral dinuclear platforms, dinuclear helices, trinuclear-triangles and tetranuclear tetrahedrons.[1] For Cu(II), several of the platform species are linked via a range of difunctional bridging ligands to yield both new discrete as well as framework materials. Using the design principles elucidated during the above studies, a range of further oligonuclear supramolecular entities based on related aryl-linked bis(triketone) ligands and polypyridyl ligands have been synthesised. The results serve to exemplify both the extraordinary supramolecular diversity and novelty that is possible using these extended ligand types. Discrete linear, triangular and interwoven products have been isolated. These include unusual mixed metal Ni(II)/Cu(II) cyclic hexanuclear species,[3] mixed metal Ni(II)/Cu(II)/ La(III) pentanuclear species and an interwoven octanuclear Fe(III) species incorporating an unprecedented ‘universal 3-ravel’ motif.[4]

combination of (bio)organic moieties and inorganic supports offers an unprecedented versatility and modularity for conceiving and constructing micro- or nanoscopic chemical devices for various (bio) analytical problems [1]. Such materials have already matured into various formats suitable for rapid analysis and allow the detection of analytes that are difficult to target by conventional portable analytical methods. A key challenge however remains sensitivity, that is, to achieve strong signal outputs from these “nanosensors”. Gated mesoporous hybrids offer several advantages in this respect [2]. For instance, if the pores of a mesoporous scaffold are loaded with a large number of suitable indicator molecules and the pores are capped after loading, removal of the caps in the anaytical step can lead to massive indicator release aka strong signal amplification. The task here is to equip such materials with the adequate recognition chemistry at the stopper linkages so that only the presence of the designated analyte can displace the caps or stoppers. Regarding sensitive detection, fluorescence-based indication naturally plays a prominent role in this area. The present contribution will highlight current trends in system design and assembly and will focus on selected capping/ uncapping chemistries that permit to achieve pronounced signal amplification. Specific systems discussed will for example include a chemodosimetrical reaction of methylmercury with a leuko dyecapped, fluorophore-loaded mesoporous silica, leading to strong signal enhancement while at the same time enabling signal ratioing [3], and an antibody-gated hybrid for the detection of TATP [4]. [1] M. Biyikal, M. Hecht, R. Martíınez-Máñez, K. Rurack, F. Sancenón, in: Supramolecular Chemistry: From Molecules to Nanomaterials, P. A. Gale, J. W. Steed (Eds.), J. Wiley & Sons, Ltd.: Chichester, 2012, 3669–3698. [2] E. Aznar, R. Martíınez-Máñez, F. Sancenón, Expert Opin. Drug Deliv., 2009, 6, 643–655. [3] E. Climent, M. D. Marcos, R. Martíınez-Máñez, F. Sancenón, J. Soto, K. Rurack, P. Amorós, Angew. Chem. Int. Ed., 2009, 48, 8519–8522. [4] E. Climent, D. Gröninger, M. A. Walter, R. Martínez-Máñez, M. G. Weller, F. Sancenón, P. Amorós, K. Rurack, submitted for publication.

Keywords: Hybrid materials, Sensing, Signal amplification

MS.B1.I1 [1] J. K. Clegg, S. S. Iremonger, M. J. Hayter, P. D. Southon, R. B. Macquart, M. B. Duriska, P. Jensen, Turner, K. A. Jolliffe, C. J. Kepert, G. V. Meehan, L. F. Lindoy, Angew. Chem. Int. Ed., 2010, 49, 1075-1078 and refs. therein. [2] C. R. K. Glasson, J. C. McMurtrie, G. V. Meehan, J. K. Clegg, L. F. Lindoy, C. A. Motti, B. Moubaraki, K. S. Murray, J. D. Cashion, Chem. Sci., 2011, 2, 540543. [3] F. Li, J. K. Clegg, P. Jensen, K. Fisher, L. F. Lindoy, G. V. Meehan, B. Moubaraki, K. S. Murray, Angew. Chem. Intern. Ed., 2009, 48, 7059-7063. [4] F. Li, J. K. Clegg, L. F. Lindoy, R. B. Macquart, G. V. Meehan, Nature Comm., 2011, 2:205.

Keywords: triangle, tetrahedron, universal-3-ravel

MS.B1.KN2 Gated Fluorogenic Hybrid Sensor Materials with Inherent Signal Amplification Knut Rurack,a Estela Climent,b Mandy Hecht,a Ramón MartínezMáñez,b aDivision 1.9 Sensor Materials, BAM Federal Institute for Materials Research and Testing, Berlin (Germany). bInstitute of Molecular Recognition and Technological Development (IDM), Polytechnic University of Valencia, Valencia (Spain). E-mail: knut. [email protected] The development of hybrid materials for sensing applications has received increasing attention in the past decade, because the

Supramolecular Sensing with Phosphonate Cavitands Enrico Dalcanale,a aDepartment of Chemistry, University of Parma, Parma, (Italy). E-mail: [email protected] The quest for selectivity is one of the key issues involved in developing new, efficient chemical sensors.[1] The use of supramolecular structures has proven to be one of the best approaches to generate new materials with molecular specificity for chemical sensing.[2] However, the direct translation of the molecular recognition properties of a given receptor from solution studies to the solid devices is not trivial, since nonspecific interactions such as dispersion forces, and material properties, like surface morphology, come into play. [3] In this lecture, I will report our recent efforts to produce specific supramolecular sensors using phosphonate cavitands as receptors. The implementation of the molecular recognition paradigm throughout the whole sensing chain will be highlighted through selected examples from our own work. Particular emphasis will be given to strategies to remove the two bottlenecks hindering the exploitation of synthetic receptors in supramolecular sensing, namely the precise transfer of the intrinsic molecular recognition properties at the gas-solid and liquidsolid interfaces and the high fidelity transduction of the interfacial molecular recognition events. In this contribution two examples will be illustrated: • Solid-gas interface: Fluorescent cavitands as selective layers for the specific detection of C1-C4 alcohols in the gas phase.[4]

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Microsymposia

Microsymposia • Solid-liquid interface: Exclusive detection of sarcosine in urine and other N-methylated guests in methanol by a cavitandfunctionalized silicon surface Tiiii-Si.[5,6] The first example demonstrates that it is possible to achieve high selectivity in chemical vapor sensing by harnessing the binding specificity of a cavitand receptor. The key requirement for transferring the molecular recognition properties from the solid state to the gassolid interface is the selection of the transduction mechanism, which must be turned on exclusively by the desired complexation mode with the analyte. The second example demonstrates how the energy of the molecular recognition between phosphonate cavitands and small alkylammonium salts can be harnessed to perform a nanomechanical task in an univocal way. The cavitand surface recognition of each individual guest drove a specific MC bending, disclosing a direct, label free and real time mean to sort them. This cavitand-MC platform was successfully benchmarked as a sensor by assaying sarcosine against glycine in aqueous solution. The detection of sarcosine has an immediate biomedical impact, as it has been recently proposed as a reliable marker for the early detection of prostate cancer in urine.[7] For urine detection, a fluorescence-based detection mode was then developed to prove the potential of Tiiii-Si as active surface for sarcosine detection with optical devices.[6] [1] L. Pirondini, E. Dalcanale Chem. Soc. Rev. 2007, 36, 695-706. [2] R. Pinalli, M. Suman, E. Dalcanale Eur. J. Org. Chem. 2004, 451-462. [3] M. Tonezzer, M. Melegari, G. Maggioni, R. Milan, G. Della Mea, E. Dalcanale Chem. Mater. 2008, 20, 6535-6542. [4] F. Maffei, P. Betti, D. Genovese, M. Montalti, L. Prodi, R. De Zorzi, S. Geremia, E. Dalcanale Angew. Chem. Int. Ed. 2011, 4654-4657. [5] M. Dionisio, G. Oliviero, D. Menozzi, S. Federici, R. M. Yebeutchou, F. P. Schmidtchen, E. Dalcanale, P. Bergese J. Am. Chem. Soc. 2012, 134, 2392-2398. [6] E. Biavardi, C. Tudisco, F. Maffei, A. Motta, C. Massera, G. G. Condorelli, E. Dalcanale Proc. Natl. Acad. Sci. USA 2012, 109, 2263-2268. [7] A.Sreekumar et al. Nature 2009, 457, 910-914.

Keywords: sensors, cavitands, interfaces

MS.B1.I2 Multichannel Ferroceneimidazole-Based Ion Pair Receptors Pedro Molina, Maria Alfonso, Alberto Tarraga, Departamento de Quimica Organica, Facultad de Quimica, Universidad de Murcia,(Spain). E-mail:[email protected] The realisation that very simple organic compounds containing heterocyclic rings capable of providing binding sites which can function as selective and effective ion receptor systems has led to work towards designing such kind of synthetic receptors that can selectively recognize ions. Among such heterocyclic units, imidazole ring behaves as an excellent hydrogen bond donor moiety in synthetic anion receptor systems, and the acidity of the NH proton of the imidazole can be tuned by changing the electronic properties of the imidazole substituents. On the other hand, the presence of a donor pyridine-like nitrogen atom within the ring, capable of selectively binding cationic species also converts to the imidazole derivatives into excellent metal ion sensors. In this sense, the binding properties of the imidazole core may be modulated by linear or angular annulation to aza-heterocycles leading to expanded imidazole derivatives bearing several binding sites.[1] In this context, ferrocene-imidazophenazine dyads 1 behave as highly selective chemosensor molecules for Pb(II) and Hg(II) cations, and the electrochemical data suggest interaction with acetate and dihydrogenfosfate anions. The OSWV technique shows its ability for detecting the formation of ion-pair complexes.[2] The ferrocene-imidazopyrene dyad 2 behaves as a host-separated ionpair receptor, the imidazole ring is able simultaneously to recognize an anion and a cation through variation of the oxidation potential of the

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ferrocene/ferrocinium redox couple and a remarkable perturbation of the emission spectrum.[3] The ferrocene-imidazoquinoxaline receptor 3 demonstrates a dramatic enhancement of hydrogensulfate anions binding by a co-bound Zn(II) or Pb(II) cations, whereas no affinity of the free receptor for this anion is observed: a strong perturbation of the redox potential of the appended ferrocene and a remarkable enhancement of the fluorescence in the presence of hydrogen sulfate anion when the Zn(II) or Pb(II) cations a bound to the cation bindingsite is observed.[4]

[1] P. Molina, A. Tarraga, F. Oton, Org. Biomol. Chem. 2012,10, 1711-1724. [2] M. Alfonso, A. Tarraga, P. Molina, J. Org. Chem. 2011, 76, 939-947.[3] M. Alfonso, A. Tarraga, P. Molina, Org. Let. 2011, 13, 6432-6435.[4] M. Alfonso, A. Espinosa, A. Tarraga, P. Molina, submitted.

Keywords:ferrocene, imidazole, ion-pair

MS.B1.I3 Structure and Function of Self-assembled Molecular Spheres Makoto Fujita, Department of Applied Chemistry, School of Engineering, The University of Tokyo, Tokyo, (Japan). E-mail: [email protected] Self-assembly is a powerful technique for the bottom-up construction of discrete, well-defined nano-scale structures. Large (> 50) multi-component systems offer mechanistic insights into biological assembly but are daunting synthetic challenges. Here, we report the self-assembly of giant, MnL2n coordination spheres from n palladium ions (M) and 2n curved bridging ligands (L) (Figure 1).[1,2] Once self-assembled, these spheres gain remarkable kinetic stability.[3] The structure of these multi-component systems is highly sensitive to the geometry of the bent ligands. Even a slight change in the ligand bend angle critically switches the final structure observed across the entire ensemble of building blocks between M24L48 and M12L24 coordination spheres.[2,4] The amplification of a small initial difference into an incommensurable difference in the resultant structures is a key mark of emergent behavior. Functionalization at the periphery[5-7] and the interior[8-12] of the giant spheres will be also discussed.

Figure 1. X-ray crystal structure of a self-assembled M24L48 complex.

[1] M. Tominaga, K. Suzuki, M. Kawano, T. Kusukawa, T. Ozeki, S. Sakamoto, K. Yamaguchi, M. Fujita 
Angew. Chem. IE 2004, 43, 5621-5625. [2] Q.-F. Sun, J. Iwasa, D. Ogawa, Y. Ishido, S. Sato, T. Ozeki, Y. Sei, K. Yamaguchi, M. Fujita 
Science 2010, 328, 1144-1147. [3] S. Sato, Y. Ishido, M. Fujita 
J. Am. Chem. Soc. 2009, 131, 6064–6065. [4] J. Bunzen, J. Iwasa, P. Bonakdarzadeh, E. Numata, K. Rissanen, S. Sato, M. Fujita, Angew. Chem. IE. 2012, 51, in press. [5] N. Kamiya, M. Tominaga, S. Sato, M. Fujita 
J. Am. Chem. Soc. 2007, 129, 3816-3817. [6] T. Kikuchi, S. Sato, M. Fujita 
J. Am. Chem. Soc. 2010, 132, 15930–15932. [7] Q.-F. Sun, S. Sato, M. Fujita, Nature Chem., 2012, 4, 333. [8] S. Sato, J. Iida, K. Suzuki, M. Kawano, T. Ozeki, M. Fujita 
Science 2006, 313, 1273-1276. [9] K. Suzuki, J. Iida, S. Sato, M. Kawano, M. Fujita 
Angew. Chem. IE. 2008, 47, 5780-5782. [10] K. Suzuki, S. Sato, M. Fujita 
Nature Chem. 2010, 2, 25-29. [11] K. Suzuki, K. Takao, S. Sato, M. Fujita 
J. Am. Chem. Soc. 2010, 132, 2544–2545. [12] K. Suzuki, K. Takao, S. Sato, M. Fujita 
Angew. Chem. IE. 2011, 50, 4858–4861.

Keywords: Self-assembly, Polyhedra, Sphere, Palladium

MS.B1.C.01 Protein Encapsulation within Well-Defined Coordination Spheres Sota Sato,a Daishi Fujita,a Kosuke Suzuki,a Maho Yagi-Utsumi,b,c Yoshiki Yamaguchi,d Nobuhiro Mizuno,e Takashi Kumasaka,e Masaki Takata,e Masanori Noda,f Susumu Uchiyama,f Koichi Kato,b,c Makoto Fujita,a aThe University of Tokyo (Japan). bInstitute for Molecular Science (Japan). cNagoya City University (Japan). dRIKEN (Japan). e Spring-8 (Japan). fOsaka University (Japan). E-mail: ssato@ appchem.t.u-tokyo.ac.jp The host-guest chemistry to trap small guest molecules has brought a wide variety of unique properties and reactivities, which can not be realized in bulk solution. Proteins are discrete molecules, but their sizes are significantly larger than conventional guest molecules. Therefore, up to now suitable synthetic host molecules for proteins have not been available, which has prevented the development of the host-guest chemistry between synthetic host and guest proteins, in spite of the expected potential to stabilize the structures and to control the functions of proteins. Here, we report the first encapsulation of a small protein, ubiquitin, within huge, well-defined coordination spheres. We reported the selfassembly of transition metal ions (M) and bidentate ligands bearing two pyridyl groups as coordination sites (L) to afford a spherical complex of M12L24 composition in quantitative yield. The obtained sphere has a large cavity, the size of which is comparable to the molecular scale of proteins. Ubiquitin was genetically mutated as Gly76Cys and covalently attached to a bidentate ligand selectively at the C-terminal under mild reaction conditions to preserve the threedimensional structure of the original ubiquitin[1]. The ligand was mixed with unsubstituted ligands, and the self-assembly with Pd(II) ions was examined. We obtained an M12L24 sphere encapsulating one ubiquitin molecule. Due to the well-defined host framework, the protein-encapsulating structure was well analyzed by NMR spectroscopy including DOSY measurements to assess the molecular size from the diffusion coefficient of the product. Ultracentrifugation analyses of both sedimentation velocity and equilibrium sedimentation experiments proved the formation of a single product and determined the molecular weight. Finally, synchrotron X-ray crystallographic analysis aided with the maximum entropy method (MEM) showed the three-dimensional structure of the protein encapsulation in the host spherical complex.

Fig. 1 Synthesis of an M12L24 sphere encapsulating a ubiquitin in the hollow. [1] D. Fujita, K. Suzuki, S. Sato, M. Yagi-Utsumi, E. Kurimoto, K. Kato, M. Fujita Chem. Lett. 2012, 41, 313-315.

Keywords: self-assembly, encapsulation

coordination

sphere,

protein

MS.B1.C.02 Effective Supramolecular Chirogenesis Effects using Schiff Base Hosts Arjan W. Kleij,a,b Martha Escárcega-Bobadilla,a Giovanni Salassa,a Eduardo C. Escudero-Adán,a Marta Martínez Belmonte,a aInstitute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007 – Tarragona (Spain). bCatalan Institute of Research and Advanced Studies (ICREA). Pg. Lluis Companys 23, 08010 – Barcelona (Spain). E-mail: [email protected] Supramolecular chirality effects are commonly encountered in natural systems such as DNA and metalloenzymes. Nature uses the most elemental building blocks (i.e., amino acids) to create chiral objects in nano-space, and throughout the last decade synthetic chemists have become inspired by these efficient approaches to design new materials with interesting properties [1]. Supramolecular chirogenesis, i.e. the induction of chirality by means of using a chiral substrate that locks a host molecule into a preferred chiral state, is an emerging field of science that has great potential for the determination of absolute configurations of various substrates,[2] enantio-selective catalysis,[3] and use in material science [4].

We recently reported a new type of bis-salphen [salphen = N,N´1,2-bis(salicylidene)-diaminobenzene] host molecule incorporating two Zn ions that are connected via a ditopically binding acetate linker [5]. Exchange of the bound acetate for chiral carboxylates results in a preferred population of one of the chiral conformations of the host system as detected by CD spectroscopy. In order to improve the potential of this type of Schiff base structures for chirogenesis effects, we have also designed a second generation host that is “free” of any

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Microsymposia guest and can be directly combined with various ditopic guests unlike for the first generation host [6]. Furthermore, we found that this new host structure can be made suitable for the binding of chiral, monotopic substrates by simple cation addition (3 in the Figure). As such, the new host structure shows great potential for the determination of absolute configurations for a widespread series of substrates. [1] Supramolecular Chirality in Top. Curr. Chem., vol. 265, eds. M. CregoCalama, D. N. Reinhoudt, Springer, Berlin 2006. [2] J. Etxebarria, A. VidalFerran, P. Ballester, Chem. Commun. 2008, 5939. [3] P. Dydio, C. Rubay, T. Gadzikwa, M. Lutz, J. N. H. Reek, J. Am. Chem. Soc. 2011, 133, 17176. [4] V. V. Borovkov, T. Harada, G. A. Hembury, Y. Inoue, R. Kuroda, Angew. Chem. Int. Ed. 2003, 42, 1746. [5] S. J. Wezenberg, G. Salassa, E. C. Escudero-Adán, J. Benet-Buchholz, A. W. Kleij, Angew. Chem. Int. Ed. 2011, 50, 713. [6] M. V. Escárcega-Bobadilla, G. Salassa, M. Martínez Belmonte, E. C. Escudero-Adán, A. W. Kleij, Chem.-Eur. J. 2012, in press.

Keywords: chirogenesis, Schiff bases, supramolecular chemistry

MS.B1.C.03 Strategic Helicity Control of Helical Metal Complexes by Molecular Leverage Shigehisa Akine, Sayaka Hotate, Tatsuya Nabeshima, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba (Japan). E-mail: [email protected] Helical molecules containing labile coordination bonds are useful as a scaffold for responsive functional molecules because external stimulus can change their helical handedness and switch their functions. We have investigated the properties and functions of singlehelical zinc(II)-lanthanide(III) complexes (Scheme 1a) that were obtained from acyclic ligands bearing multiple N2O2 coordination sites [1]. Since their helical structures are maintained by labile coordination bonds, dynamic interconversion between the right- and left-handed forms was expected. In this study, we aimed to create a novel helix inversion system that is remotely driven using a molecular leverage mechanism (Scheme 1b). We have previously reported that the helical handedness of the helical tetranulear complexes can be efficiently controlled by the introduction of a chiral salen unit (Scheme 1a) [1]. If we suitably change the N–C–C–N torsion angle of the chiral salen moiety, we can invert the helical handedness of the helical complexes. We designed a helical metal complex [LZn3La] with two crown ether moieties, which can change the helical handedness upon the binding with diammonium guests (Scheme 1c). Binding with a short diammonium guest (1,4-butanediammonium salt) gave the P isomer as the major isomer. On the other hand, a long guest (1,12-dodecanediammonium salt) caused helix inversion to give the M isomer. Consequently, the differences in the molecular lengths were efficiently translated into the helical handedness via the novel molecular leverage mechanism [2].

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[1] For reviews, see: S. Akine, T. Nabeshima, Dalton Trans., 2009, 1039510408; S. Akine, J. Inclusion Phenom. Macrocycl. Chem., 2012, 72, 25-54. [2] S. Akine, S. Hotate, T. Nabeshima, J. Am. Chem. Soc., 2011, 133, 13868-13871.

Keywords: helical structure, molecular machine, salen complex

MS.B1.C.04 Structure-Function Relationships in Coordination Cages Guido H. Clever, Institute for Inorganic Chemistry, Georg-August University Goettingen, (Germany). E-mail: [email protected] Self-assembled supramolecular coordination cages that form quantitatively in solution by simple mixing of organic ligands and metal cations such as Pd(II) show functions such as selective guest uptake and release, anion sensing and catalysis in confined environments. Since even very simple organic ligands can lead to the spontaneous formation of rather complex structures with interesting functions, such cage compounds promise to find application in new materials, diagnostic systems and approaches of controlled drug release. The focus of our particular interest lays on systems characterized by unique topologies, lowered symmetries and stimuli-responsive ligands. We have recently introduced a new dimeric, interpenetrated coordination cage that shows a record breaking affinity (1024 M-2) for the allosteric binding of two chloride anions in its outer two pockets (Figure a) [1]. This double cage is even capable of dissolving AgCl in acetonitrile. New insights into the mechanism of the positive cooperative binding process, such as the elucidation of the screw motion associated with the uptake of chloride, are presented. Since we learned to control the key factors relevant to interpenetration, further examples of interpenetrated double cages based on other functional backbones such as phenothiazine have been realized and will be reported. As another example of the quantitative formation of a topologically complex coordination cage, the formation and NMR-based structure elucidation of a discrete compound in the shape of a double trefoil knot is introduced (Figure b) [2]. Based on light-switchable ligands we could further prepare a novel coordination cage that exhibits a stimuli-responsive change of its structure which in turn modulates its ability to bind negatively charged guests in its interior. This system serves as a model for the light-triggered controlled release of (for example) bioactive anions from the inside of a discrete carrier.

Microsymposia [1] Y.H. Lau, P. Rutledge, M. Watkinson, M. H. Todd, Chem. Soc. Rev., 2011, 40, 2848-2866. [2] E. Tamanini. S.E.J. Rigby, M. Motevalli, M.H. Todd, M. Watkinson, Chem Eur. J., 2009, 15, 3720-3728. [3] E. Tamanini, A. Katewa, L. Sedger, M.H. Todd, M. Watkinson, Inorg. Chem., 2009, 48, 319-324. [4] E. Tamanini, K. Flavin, M. Motevalli, S. Piperno, L.A. Gheber, M.H. Todd, M. Watkinson, “Inorg. Chem., 2010, 49, 3789-3800. [5] K. Jobe, C.H. Brennan, M. Motevalli, S.M. Goldup, M. Watkinson, Chem. Commun., 2011, 47, 6036-6038. [6] H. Lahali, K. Jobe, M. Watkinson and S.M. Goldup, Angew. Chem. Int. Ed., 2011, 50, 4151-4155.

[1] S. Freye, J. Hey, A. Torras-Galán, D. Stalke, R. Herbst-Irmer, M. John, G. H. Clever, Angew. Chem. Int. Ed. 2012, 51, 2191-2194. [2] D. M. Engelhard, S. Freye, K. Grohe, M. John, G. H. Clever, Angew. Chem. Int. Ed. 2012, in press, DOI: 10.1002/anie.201200611.

Keywords: supramolecular chemistry, anion binding, coordination cages

MS.B1.C.05 Click to detect: The next generation Michael Watkinson, Kajally Jobe, Jessica Pancholi, Gregory A. Chass and Stephen M. Goldup, School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London, E1 4NS (UK). E-mail: [email protected] In recent years the ‘click’-generated triazole has been shown to be a versatile functional group in a diverse range of sensing applications. These include supramolecular motifs for cation recognition, open chain sensors, sensors relying on large-scale changes to macromolecular assemblies, anion binding sensors which utilise the polarised triazole C-H bond, sensors for molecules ranging from small organic species to whole proteins, and sensors using the occurrence of the click reaction itself as a detection mechanism.[1] Our interests have focussed on the application of click functionalised azamacrocyclic ligands in the allosteric detection of biological analytes in 1,[2] as well as the fluorescence sensing of the biologically important zinc cation with 2 and related systems in vitro, in apoptopic murine thymocytes and in the model organisms zebrafish (Danio rerio) and fruit flies (Drosophila melanogaster).[3-5] We have also utilised click chemistry to generate unusually small [2]rotaxanes, such as 3, in excellent yield.[6] Our recent efforts in this area have allowed us to develop a better understanding of our allosteric sensor system through a combination of synthesis, DFT calculations and EPR spectroscopy. We have also extended our zinc sensor systems to provide biologically more desirable excitation and emission wavelengths, as well as systems which target specific biological space. Finally, we have incorporated our zinc sensing motif into a [2]rotaxane closely related to 3, providing a new class of supramolecular zinc sensor.

MS.B1.C.06 Axle Functionalized Heterometallic Rotaxanes and their Supramolecular Assembly Grigore A. Timco,a Bryony Cross,a Harapriya Rath,a Antonio L. Fernández-Mato,a Robin G. Pritchard,a George F. S. Whitehead,a Richard E. P. Winpenny,a,b aThe Lewis Magnetism Laboratory School of Chemistry and bPhoton Science Institute, University of Manchester, Manchester (United Kingdom). E-mail: grigore.timco@manchester. ac.uk The synthesis and characterization of a series of hybrid organicinorganic rotaxanes and their supramolecular assembly will be described. The ring components are heterometallic octanuclear metallacycles ( [Cr7MF8(O2CR)16]-; M2+ = Ni, Co, Fe, Zn ) in which the metal centers are bridged by fluoride and O2CR- carboxylate anions; the thread components feature dialkyl-ammonium units that template the formation of the heterometallic rings about the axle to form discrete rotaxane molecules in which inorganic and organic structural units are linked together mechanically at the molecular level [1,2]. To date, most threads (axles) were constructed with just bulky ‘stoppers’ at each end of the axle to prevent subsequent dethreading of the ring assembled around the ammonium template. Space-filling models suggested that the cavities of heterometallic Cr7MF8(O2CR)16 rings are small enough that even a phenyl group should prevent dethreading. Thereafter we used axles functionalised with 4-(methylthio)phenyl and /or 4-pyridyl group as ‘stoppers’ to make [2] and [3] rotaxane. In the rotaxanes stoppered at one end by 4-methylthio phenyl group and on other end by 4-pyridyl group the pyridine moiety is free to bind to further metal sites. Thus we can use the hybrid organic-inorganic rotaxanes functionalised with these ‘stoppers’ as building blocks to produce new assemblies of rotaxanes (e.g. show below) as well as for grafting them on a gold surface.

[1] C.-F.Lee, D. A. Leigh, R. G. Pritchard, D. Schultz, S. J. Teat, G. A.Timco, R. E. P. Winpenny, Nature, 2009, 458, 314–318. [2] B. Ballesteros, T. B. Faust, C.-F. Lee, D. A. Leigh, C. A. Muryn, R. G. Pritchard, D. Schultz, S. J. Teat, G. A. Timco, R. E. P. Winpenny, J. Am. Chem. Soc. 2010, 132, 15435–15444.

Keywords: heterometallic, rotaxane, assembly

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Keywords: sensors, click chemistry, azamacrocycles

Microsymposia MS.B1.C.07 Lanthanide Complexes as a Basis for Nanomaterial with Stimuli Responsive Luminescence Asiya Mustafina, Olga Bochkova, Alsu Muhametshina, Nikolay Davydov, Alexander Konovalov, A.E.Arbuzov Institute of Organic and Physical Chemistry KSC RAS, Kazan, 420088, Russia. E-mail: [email protected] The stimuli responsive colloids are of great importance for the biomedical and biosensing applications. The core-shell morphology enables to provide both the deeper encapsulation of the hazardous luminescent compounds into the core and the flexible binding of the molecules exhibiting required chromophoric properties. The present report is focused on lanthanide complexes as luminescent components of nanoparticles due to great advantages of the lanthanide-centered luminescence in the comparison with organic luminophores. The obtained results reveal that the silica coating improves photophysical properties of Tb(III) complex encapsulated into silica matrix. The increased photostability and poor leakage should be noted as advantages of this type of morphology. Various routes of the surface modifications, such as the adsorption of cationic surfactants and polyelectrolytes, as well as the covalent fixing of amino-groups will be also represented as a ways to gain in receptor properties towards metal ions and dyes. Moreover the quenching of Tb(III) centered luminescence resulted from the energy transfer from the silica coated luminophores to quenching molecules at the silica/water interface was revealed. The estimated quenching regularities and the flexible binding of both metal ions and dyes at the silica/water interface provide a prerequisite for the stimuli responsibility of the colloids. The quenching of the Tb(III) centered emission by dyes and further reestablishment of the luminescent signal due to the substrate induced displacement of quenching molecules enables to recognize anionic phospholipids versus their zwitter ionic analogues through the fluorescent response. Moreover the content of inpurities in commercially availible phospholipids can be evaluated by measuring the luminescent responce of Tb-doped nanoparticles in the presence of dye molecules as a probe. The complex formation of d-metal ions at the interface of Tb(III) doped silica nanoparticles modified by amino-groups as a route to sense d-metal ions and some organic molecules, such as catechols and ATP will be discussed in this report. [1] M. Jones, J. Smith, Abbreviated Journal Name, 2012, 9, 9-13. [1] A.R. Mustafina, S.V. Fedorenko, O.D. Konovalova, A.Yu. Menshikova, N.N. Shevchenko, S.E. Soloveva, A.I. Konovalov, I.S. Antipin. Langmuir 2009, 25, 3146-3151. [2] S.V. Fedorenko, O.D. Bochkova, A.R. Mustafina, V.A. Burilov, M.K. Kadirov, C.V. Kholin, I.R. Nizameev, V.V. Skripacheva, A.Yu. Menshikova, I.S. Antipin, A.I. Konovalov. J. Phys. Chem. C, 2010, 114 , 6350– 6355. [3] O.D. Bochkova, A.R. Mustafina, A.R. Mukhametshina, V.A. Burilov, A.V. Nemtarev, V.F. Mironov, A.I. Konovalov. Talanta, 2012, 93, 233-238.

Keywords: luminescence, sensing, nanoparticles

MS.B1.C.08 Finite Nano-Scale Metallo-Supramolecular Ensembles -- The Art of Assembly Feng Li,a,b Jack K. Clegg,b,c Cameron J. Kepertb and Leonard F. Lindoy,b aSchool of Science and Health, University of Western Sydney, Locked Bag 1797, Penrith NSW 2751, Australia. bSchool of Chemistry, The University of Sydney, NSW 2006, Australia. cSchool of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia. E-mail: [email protected] In the realm of supramolecular chemistry, finite nano-scale

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metallo-supramolecular ensembles with interesting and beautiful molecular structures have received very considerable attention over recent years. [1], [2], [3] The resulting metallo-architectures range from simple molecular ellipses, through higher polygons and large polyhedrons, to a small number of intricately interwoven structures that bridge the boundaries between Art and Science. These ensembles, which typically form on the nanometer scale, display both considerable beauty and applications. However, the generation of new structures of this type has remained a very significant synthetic challenge. A condition for the rational strategies of such metal organic structures is that the metal ion(s) and organic component(s) display the required steric and electronic complementarity to promote formation of the molecular architecture of interest. In the first part of my lecture I will give a brief account between arts and science and how recent research has been done in metallo-supramolecular chemistry over time. In the second part, I will introduce how to design and synthesize finite nano-scale metallo-supramolecular assemblies. In the last part of my talk, I will discuss one of my more recent interests, that is, a potential application in anion detection by temperature control using spincrossover materials.

[1] F. Li, J. K. Clegg, L. F. Lindoy, R. B. Macquart and G. V. Meehan, Nat. Commun., 2011, 2:205, doi: 10.1038/ncomms1208. [2] F. Li, J. K. Clegg, L. Goux-Capes, G. Chastanet, D. M. D’Alessandro, J.-F. Létard and C. J. Kepert, Angew. Chem., Int. Ed., 2011, 50, 2820-2823. [3] F. Li, J. K. Clegg, P. Jensen, K. Fisher, L. F. Lindoy, G. V. Meehan, B. Moubaraki and K. S. Murray, Angew. Chem. Int. Ed., 2009, 48, 7059-7063.

Keywords: finite, metallo-supramolecular, assembly

MS.B1.C.09 Programmable Metal Arraying in Porphyrin/Phthalocyanine Four-fold Rotaxanes Kentaro Tanaka,a,b Yasuyuki Yamada,a,c Yu Ishihara,a Nozomi Mihara,a Shinya Shibano,a aDepartment of Chemistry, Nagoya University, Nagoya, (Japan). bCREST, Japan Science and Technology Agency (Japan). cRCMS, Nagoya University, Nagoya, (Japan). E-mail: [email protected] Electronic communication between molecules is sensitive to their relative orientation. Mechanically interlocked supramolecular motives, such as catenanes and rotaxanes, are promising molecular systems to array functionalized building blocks to regulate their precise intermolecular communications, because two or more molecular components are inseparable but their interactions are flexibly convertible in these supramolecular systems. Recently, we have reported a mechanically linked cofacially stacked arrays of a metalloporphyrin and metallophthalocyanine units by formation of a four-fold rotaxane and its switchable spin–spin communication induced by external stimuli [1]. A four-fold rotaxane 3 was prepared from phthalocyanine with four peripheral crown ethers 1 and tetradactyl porphyrin with four alkyl ammonium chains 2. In a dinuclear Cu2+ complex of the fourfold rotaxane, the Cu2+-porphyrin and the Cu2+-phthalocyanine were stacked efficiently on one another to afford spin-spin communication. Spin states of the dinuclear complex were reversibly switchable

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between the protonated (doublet) and deprotonated forms (singlet) (Fig. 1). The supramolecular motif is of use in heterogeneous metal arraying. Different metal ions can be inserted into the phthalocyanine site and the porphyrin site. A hetero-dinuclear complex consisted of Cu2+-porphyrin and Zn2+-phthalocyanine was obtained. Moreover, this scaffold is extensible to programmable one-dimensional arraying of phthalocyanines on the porphyrin template. The number of ammonium moieties on each peripheral alkyl chain of the template porphyrin can be used to regulate the number of assembled phthalocyanines, yielding one-dimensional stacked phthalocyanine arrays. The switching ability of the intermolecular communication could possibly extend from the spin-spin interaction, reported in this work, to electron and energy transfer, catalytic reaction on metal centers, e.t.c.

[1] (a) R. Chakrabarty, P. S. Mukherjee, P. J. Stang Chem. Rev. 2011, 111, 6810. (b) J. A. Thomas, Dalton Trans., 2011, 40, 12005. [3] (a) N. Shan, S. Vickers, H. Adams, M. D. Ward, J. A. Thomas, Angew. Chem., Int. Ed., 2004, 43, 3938. (b) N. Shan, S. Vickers, J. D. Ingram, T. L. Easun, H. Adams, M. D. Ward, J. A. Thomas, Dalton Trans., 2006, 2900. [4] (a) P. de Wolf, S. L. Heath and J. A. Thomas, Chem. Commun., 2002, 2540; (b) P. de Wolf, P. Waywell, M. Hanson, S. L. Heath, A. J. H. M. Meijer, S. J. Teat and J. A. Thomas, Chem. Eur. J., 2006, 12, 2188. (c) D. Ghosh, H. Ahmad and J. A. Thomas, Chem. Commun., 2009, 2947. [5] A. Zubi, P. J. Costa, V. Félix , J. A. Thomas, submitted.

Keywords: Ruthenium, devices, self-assembly Fig. 1 Porphyrin/Phthalocyanine Four-fold Rotaxane [1] Y. Yamada, M. Okamoto, K. Furukawa, T. Kato, K. Tanaka, Angew. Chem. Int. Ed., 51, 709-713 (2012).

Keywords: rotaxane, metal arraying, heteronuclear complex

MS.B1.C.10 Self-Assembled Redox-Active Metallomacrocycles as AnionSwitched Molecular Devices Jim A Thomas,a Ahmed Zubi,a Paulo J Costa,b Ashley Wragg,a Vítor Félix,b aDepartment of Chemistry, University of Sheffield, Brook Hill, Sheffield, UK, bDepartamento de Química, CICECO and Secção Autónoma de Ciências da Saúde, Universidade de Aveiro, 3810-193, Aveiro, Portugal. E-mail: [email protected] In the last two decades, metal-ion directed construction of discrete multi-component assemblies has emerged as a powerful and versatile synthetic route to supramolecular architectures. [1] Despite the huge amount of activity in this area, reports on metallomacrocycles containing ruthenium(II) moieties are very rare – an observation that reflects the kinetically inert nature of this low spin d6-metal center. [2] So as to combine the attractive optical and electrochemical properties of oligonuclear ruthenium systems with the synthetic versatility of metal-ion direct self-assembly, we are investigating routes towards self-assembled metallomacrocycles that embed ruthenium units within their architecture. [3,4] In previous work, we demonstrated that selected ruthenium(II) “building blocks” react with suitably hindered adenine derivatives to form metallomacrocyclic bowls such as 13+, Scheme 1, which can be reversibly oxidized into mixed valence states. [3] Given that 13+ is cationic and possesses an array of possible hydrogen-bonding donor groups, we reasoned that it would be a host for anionic guests. Herein we report on the host-guest chemistry of 13+, describing how its optical, electrochemical, and electron transfer properties are modulated by recognition processes. [5].

MS.B1.C.11 Creation of Supramolecular Architectures Based on Chiral Gold(I) Metalloligands Takumi Konno, Raeeun Lee, Asako Igashira-Kamiyama, Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka (Japan). E-mail: [email protected] Considerable progress has been made in the design and creation of supramolecular systems in recent years. In these systems, selfassembly processes, which spontaneously afford molecular aggregates from relatively simple building blocks via noncovalent interactions, are employed to construct highly organized structures as nature creates functional biological aggregates from smaller molecular subunits via noncovalent interactions. Our interest has been directed toward the metal-mediated molecular self-assembly based on chiral metal complexes with sulfur-containing aminocarboxylate, which serve as a metalloligand toward various metal ions.1 Recently, we have found that the aurate(I) complex with two d-penicillaminates, [Au(d-pen)2]3–, functions as a chiral multidentate metalloligand that can bind to metal ions through coordinated thiolato and non-coordinated amine and carboxylate groups, producing a variety of chiral polynuclear and supramolecular species. To expand the range of this chemistry, we thought it worthwhile to introduce a digold(I) unit having bis(diphenylphosphino)alkane as a linker, in place of the AuI atom in [Au(d-pen)2]3–. Here we report that the digold(I) complex having 1,2-bis(diphenylphosphino)ethane, [Au2(d-Hpen)2(dppe)], serves as a chiral bis(tridentate-N,O,S) metalloligand toward CoIII to form a cationic S-bridged AuI4CoIII2 hexanuclear complex, [Au4Co2(dppe)2(dpen)4]2+. Remarkably, this hexanuclear complex was found to crystallize with ClO4– to form metallosupramolecular ionic crystals, in which 6 AuI4CoIII2 complex-cations are self-assembled to form a big octahedral supramolecule, with the concomitant aggregation of 10 ClO4– anions into an amazing adamantine-like anionic cluster (Figure 1).

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Figure 1. A cationic (AuI4CoIII2)6 supramolecule and an anionic (ClO4–)10 cluster in the metallosupramolecular ionic crystal. [1] A. Toyota, T. Yamaguchi, A. I.-Kamiyama, T. Kawamoto, T. Konno, Angew. Chem. Int. Ed., 2005, 44, 1088. M. Taguchi, A. I. -Kamiyama, T. Kajiwara, T. Konno, Angew. Chem. Int. Ed., 2007, 46, 2422. Y. Sameshima, N. Yoshinari, K. Tsuge, A. I.-Kamiyama, T. Konno, Angew. Chem. Int. Ed., 2009, 48, 8469. A. I.-Kamiyama, T. Konno, Dalton Trans., 2011, 40, 7249 (Perspective).

Keywords: Supramolecular Heterometallic aggregates

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chemistry,

Nanostructures,

9 - 13 September 2012

Microsymposia

Autonomous Discovery of Inorganic Clusters with a Networked Flow System Array Leroy Cronin,a aSchool of Chemistry, University of Glasgow, Glasgow, G12 8QQ (UK) E-mail: [email protected]; web: http://www. croninlab.com The synthesis of supramolecular macromolecules e.g. coordination and polyoxometalate clusters is both time consuming and limited by lack of reproducibility, however flow system approaches, now common in organic synthesis, have not been fully utilized for the synthesis of self-assembled systems. Here I will present a number of new concepts for discovery, scale-up and discovering new reaction ‘wiring’ using a flow system array[1], see Figure, as well as in a 3d-printer system[2]. To do this we combine an automated flow process with screening and scaling-up the syntheses of self-assembled inorganic clusters (polyoxometalates and manganese-based single molecule magnets). Scale up of the synthesis of these architectures was achieved by programing a multiple reactor system to sequentially vary reaction parameters, thus exploring a large parameter space in a much shorter time than conventionally possible. Successful conditions for product isolation could be easily identified from the array of reactions, and a direct route to “scale-up” was then immediately available simply by continuous application of those flow conditions. Also, the potential for the array as a discovery tool, as well as scale up, is highlighted as well as the use of this tool as means to map the interdependent reaction network allowing scanning for new function, molecular structure applicable not only in inorganic but also organic synthesis.

counterions. We believe that organic-inorganic POMs provide an alternative and that the covalent link of functionalized POMs to functional moieties, to polymers or to surfaces could improve the control of the interaction between the different components, the POM dispersion and the stability of the whole assembly. Furthermore, while direct functionalization of POMs is now well-documented, access to more intricate targets may be easier from preformed hybrid POM platforms, prepared and purified at a large scale. We will present the platforms we are currently exploiting and the post-functionalization reactions we are investigating to tackle two fields of applications: the photosensitization of POMs for solar energy conversion and the surface grafting of POMs as redox active molecules for molecular electronics.

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MS.B2.KN1

[1] B. Matt, C. Coudret, C. Viala, D. Jouvenot, F. Loiseau, G. Izzet and A. Proust, Inorg. Chem., 2011, 50, 7761-7768. [2] B. Matt, S. Renaudineau, L. M. Chamoreau, C. Afonso, G. Izzet and A. Proust, J. Org. Chem., 2011, 76, 3107-3112. [3] B. Matt, J. Moussa, L. M. Chamoreau, C. Afonso, A. Proust, H. Amouri and G. Izzet, Organometallics, 2012, 31, 35-38.

Figure: The flow system array with the parameter set, array, and synthesised polyoxometalate library. [1] H. N. Miras, G. J. T. Cooper, D.-L. Long, H. Bögge, A. Müller, C. Streb and L. Cronin, Science, 2010, 327, 72-74. [2] M. D. Symes, P. J. Kitson, J. Yan, C. J. Richmond, G. J. T. Cooper, R. W. Bowman, T. Vilbrandt, L. Cronin, Nat. Chem., 2012, 4, 349-354.

Keywords: polyoxometalates, molecular networks, complex systems

MS.B2.KN2 Post-Functionalization of Hybrid POM Platforms toward Functional Systems Anna Proust, Benjamin Matt, Corentin Rinfray, Guillaume Izzet Institut Parisien de Chimie Moléculaire, UMR CNRS 7201, Université Pierre et Marie Curie Paris 06, 4 Place Jussieu, Case Courrier 42, 75252 Paris Cedex 05 (France). E-mail: [email protected] Polyoxometalates (POMs) have remarkable properties and a great deal of potential. However, elaboration of molecular materials is conditioned to a processing step. This has been mainly addressed through an electrostatic approach based on the exchange of their

Keywords: polyoxometalates, photosensitizers

organic-inorganic

hybrids,

MS.B2.I1 Revisiting Mo Blue Nanoclusters: Strategies for Synthesis and Functionalization Paul Kögerler, Institute of Inorganic Chemistry, RWTH Aachen University, Aachen (Germany) and Peter Grünberg Institute, Research Centre Jülich, Jülich (Germany). E-mail: [email protected] The self-assembly of soluble molybdenum blue species from simple molybdate solutions is primarily associated with giant wheelshaped cluster anions, derived from the {MoV/VI154/176} archetypes, and a {MoV/VI368} lemon-shaped cluster, with both of these structural archetypes based on commensurate sets of transferable building blocks. Due to their intense intervalence charge transfer absorptions in the near IR, mixed-valent molybdenum blue-type species display characteristic resonance Raman spectra for appropriate excitation lines. The combined use of Raman spectroscopy and kinetic recipitation as self-assembly monitoring techniques has been proven as a key ingredient to mapping the realm of molybdenum blue species as a function of fundamental reaction parameters such as concentrations, pH, or temperature. For example, this approach allowed us to establish spherical {Mo102}-

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Microsymposia type Keplerates as a distinct – and for certain conditions even as the dominant – component of molybdenum blue solutions. Knowing the boundary conditions for polyoxomolybdates is also essential in order to devise synthesis strategies novel cluster structures with increased hierarchical complexity and added functional groups. The presentation will summarize our current results in this direction and illustrate how these molybdenum blue-focused synthesis strategies can be used for the isolation of new magnetically functionalized polyoxomolybdates. Keywords: polyoxomolybdates, spectroscopy

molybdenum

blue,

Raman

MS.B2.I2

as a new type of multi-dentate O-donor ligands to assemble various transition metal or lanthanide ions into aggregates with interesting magnetic properties, especially the single-molecule magnet (SMM) behavior.[1-4] In this research field, several POM-based SMMs or SMMs decorated by POM ligands have been reported.[2] Furthermore, the hybrid POM materials behaving as SMMs have also been prepared by dispersing high-spin anisotropic units (like SMMs) into the porous anionic POM-based structures.[3] A recent progress has also focused on the construction of new 3d-4f heterometallic SMMs based on POMs.[4] In this report, the recent advance on POM-mediated SMMs has been summarized. The advantages and lacks of POMs as an inorganic media in the construction of new type of SMMs were evaluated. A series of new results in this research field were introduced.

Anomalous Solubility of Alkaline Polyoxometalates May Nyman,a Yu Hou,b Mark R. Antonioc. aDepartment Chemistry, Oregon State University, Corvallis, Oregon (USA). a,b Sandia National Laboratories, Albuquerque, New Mexico (USA). cArgonne National Laboratory, Argonne, Illinois (USA). Polyoxometalates (POMs), discrete metal-oxo clusters of the early d0 transition metals (V, Nb, Ta, Mo, W) always carry a negative charge in their native water-soluble forms. This, of course necessitates the use of countercations for crystallization, dissolution, and sometimes templating cluster growth. The countercations of POMs are often overlooked for the interesting properties of the POMs themselves; but POMs of Nb and Ta necessitate consideration of the countercations in order to fully understand and develop their chemistries. While the POMs of the more familiar Mo and W (and usually V) are assembled and stable in aqueous acid, the POMs of Nb and Ta are assembled and stable in aqueous base. The POMs of Nb and Ta also have much higher anionic charges (i.e. for the common Keggin ion [SiNb12O40]16vs. [SiW12O40]4-); and this controls their assembly and behaviour in aqueous media. While most salts with alkali cations (including the acidic POM families) decrease in aqueous solubility with decreasing hydration sphere from Li>Na>K>Rb>Cs; POMs of Nb present the opposite behaviour. We have utilized Small-angle X-ray Scattering (SAXS) to investigate the ion-association behaviour of Nb-POMs and Ta-POMs, and found the extensive ion-association that is observed in the solidstate prevails in the aqueous state, but differs in surprising ways between Nb-POMs and Ta-POMs. The way in which these countercations affect synthetic strategies, cluster geometries, aqueous behaviour and solidstate assemblies will be discussed in this presentation. Applications unique to the alkaline POMs will also be briefly presented. [1] Y. Hou, T.M. Alam, M.A. Rodriguez, M. Nyman Chem Commun, 2012, in press. [2] Y. Hou, M.A. Rodriguez, M. Nyman Angew. Chem. Int. Ed, 2011, 50, 12514-12517. [3] M. Nyman Angew. Dalton Transact, 2011, 50, 8049-8058.

Keywords: polyoxometalate, niobates, ion-pairing

MS.B2.I3 Polyoxometalate-mediated Single-Molecule Magnets Yangguang Li,a Zhiming Zhang,a Yonghui Wang,a Enbo Wang,a aKey Laboratory of Polyoxometalate Science of Ministry of Education, Faculty of Chemistry, Northeast Normal University, Changchun, Jilin, 130024 (China). E-mail: [email protected] Polyoxometalates (POMs) are unique inorganic nano-sized clusters with oxygen-enriched surface and controllable size, shape and charge. In the past few years, such molecular objects have been considered

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Fig. 1 (a) {Mn4Dy} cluster (b) four Dy3+ ions supported by trilacunary polyoxotungstates [1] (a) J. M. C. Juan, E. Coronado, Coord. Chem. Rev., 1999, 193, 361; (b) D. L. Long, R. Tsunashima, L. Cronin, Angew. Chem. Int. Ed. 2010, 49, 1736. [2] (a) M. A. AlDamen, J. M. Clemente-Juan, E. Coronado, C. Martí-Gastaldo, A. Gaita-Ariňo, J. Am. Chem. Soc., 2008, 130, 8874; (b) C. Ritchie, A. Ferguson, H. Nojiri, H. N. Miras, Y. F. Song, D. L. Long, E. Burkholder, M. Murrie, P. Kögerler, E. K. Brechin, L. Cronin, Angew. Chem. Int. Ed., 2008, 47, 5609; (c) J. D. Compain, P. Mialane, A. Dolbecq, I. M. Mbomekallé, J. Marrot, F. Sécheresse, E. Rivière, G. Rogez, W. Wernsdorfer, Angew. Chem. Int. Ed., 2009, 48, 3077; (d) X. K. Fang, M. Speldrich, H. Schilder, R. Cao, K. P. O’Halloran, C. L. Hill, P. Kögerler, Chem. Commun., 2010, 46, 2760; (e) M. Ibrahim, Y. Lan, B. S. Bassil, Y. X. Xiang, A. Suchopar, A. K. Powell, U. Kortz, Angew. Chem. Int. Ed., 2011, 50, 4708; (f) C. Ritchie, M. Speldrich, R. W. Gable, L. Sorace, P. Kögerler, C. Boskovic, Inorg. Chem., 2011, 50, 7004. [3] (a) Q. Wu, Y. G. Li, Y. H. Wang, R. Clérac, Y. Lu, E. B. Wang, Chem. Commun., 2009, 5743; (b) Y. Sawada, W. Kosaka, Y. Hayashi, H. Miyasaka, Inorg. Chem., 2012, 51, 4824. [4] (a) S. Reinoso, Dalton Trans., 2011, 40, 6610; (b) X.J. Feng, W.Z. Zhou, Y.G. Li, H.S. Ke, J.K. Tang, R. Clérac, Y.H. Wang, Z.M. Su, E.B. Wang, Inorg. Chem., 2012, 51, 4824.

Keywords: polyoxometalate, inorganic ligand, single-molecule magnet

MS.B2.C.01 Polyoxometalates as Electron Sponges Hirofumi Yoshikawa,a Heng Wang,a Kunio Awaga,a aGraduate School of Science, Nagoya University, Nagoya(Japan). E-mail: yoshikawah@ chem.nagoya-u.ac.jp Development of high-performance rechargeable batteries is one of the most important research subjects due to the ever-increasing energy demands and pressing environmental concerns. Recently, we proposed a new type of lithium battery, the molecular cluster battery (MCB), in which the cathode active materials are polynuclear metal complexes

(molecular clusters), in order to achieve both high battery capacity and fast charging/discharging.[1] Since polyoxometalates (POMs) have reversible multi-electron redox properties, the POM-MCBs, in which a Keggin-type POM, [PMo12O40]3-, is utilized as a cathode-active material with a lithium metal anode, exhibit a large capacity of ca. 270 Ah/kg, which is higher than those of the usual lithium ion batteries (ca. 150 Ah/kg). Here, to investigate the valence and structural changes of the POMs in the battery reaction, we carried out in operando Mo K-edge X-ray absorption fine structure (XAFS) measurements on the POM-MCBs. X-ray absorption near edge structure (XANES) analyses demonstrate that all the twelve Mo6+ ions in [PMo12O40]3- are reduced to Mo4+ in the discharging process. This means the formation of a super-reduced state of the POM, namely [PMo12O40]27-, which stores twenty-four electrons, and this electron number can explain the large capacity of the POMMCBs. Furthermore, extended X-ray absorption fine structure (EXAFS) analyses reveal the molecular structure of [PMo12O40]27-, which slightly reduces in size from the original [PMo12O40]3-, and involves Mo4+ metal-metal bonded triangles (see Figure 1). Density functional theory (DFT) calculations suggest that these triangles are formed due to the large number of additional electrons in the super-reduced state. These results suggest that the solid-state electrochemistry of the battery reactions enables the formation of the highly reduced species. This electron sponge behavior is a newly revealed characteristic of POMs, and indicates that they are promising cathode active materials for highperformance rechargeable batteries.[2] We also report nano-hybrid materials between POMs and SWNTs, in which Keggin-type POMs, TBA3[PMo12O40] (TBA = (C4H9)4N+), are individually adsorbed on the SWNT surfaces for application to the cathode active materials of MCBs (see Figure 2). The charging/ discharging measurements for the POM-SWNT hybrid MCBs indicate a higher battery capacity and a faster charging/discharging compared with those of the initial POM MCBs, in which the cathodes consist of microcrystals of POM and carbon black particles.[3]

[1] H. Yoshikawa et al., Chem. Commun., 2007, 3169-3171. [2] H. Yoshikawa et al., J. Am. Chem. Soc., 2012, 134, 4918-4924. [3] H. Yoshikawa et al., Angew. Chem. Int. Ed. 2011, 50, 3471-3474.

Keywords: polyoxometalates, electron sponges, nano-hybrid materials

MS.B2.C.02 Complexes of Polyoxometalates with Noble Metals Maxim N. Sokolov,a,b aNikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia. bNovosibirsk State University, Novosibirsk, Russia. E-mail: [email protected] Noble metal-containing polyoxometalates (POM) represent an area which attracts a keen attention of various research groups due to a number of interesting properties, such as catalytic oxidation of water and/or various organic substrates, transfer of nitrogen etc.

Incorporation of noble metals into POM offers new structure features and reactivity patterns, such as strong metal-metal bonding, unique stereochemistry around noble metal ion, chemical softness, relative stability of organometallic derivatives and complexes with pi-acceptor ligands. This contribution reports new results in the field of coordination chemistry of Rh, Ir, Ru and Pt with homo- and heteropolytungstates. The key points are: 1. Ir POM chemistry – emerging after a long neglect. Stabilization of Ir(II), Ir(III) and Ir(IV) in Keggin, Linquist and Anderson-type structures. 2. Incorporation of M-M bound and polynuclear units into POM: stabilization of rare Ir24+ group by lacunary POM with Keggin and Lindquist structure; Rh24+ analogues; unique Rh tungstate with {Rh4W18} core. 3. First Pt(II) tungstate: how square planar geometry adopts to the POM coordination requirements. 4. Unusually stable and easily available organometallic derivatives [PW11O39M-R]5- (M = Rh, Ir; R = CH3, Ph, Fc). 5. CO and NO-functionalized Ru-containing POM. [1] M.N. Sokolov, S.A. Adonin, D.A. Mainichev et al. Chem. Commun. 2011, 47, 7833. [2] M.N. Sokolov, S.A. Adonin et al., Chem. Comm. 2012, in perss. [3] M.N. Sokolov, S.A. Adonin, Dalton Trans. 2012, in press.

Keywords: Polyoxometalates, Noble metals, Clusters

MS.B2.C.03 Beyond the homogeneous media: Modelling the adsorption of α -Keggin on metallic surfaces Xavier Aparicio-Anglès,a Pere Miró,b Anna Clotet,a Carles Bo,a,b Josep M. Poblet, aDepartament de Química Física i Inorgànica, Universitat Rovira i Virgili, Tarragona, (Spain). bInstitut Català d’Investigació Química, Tarragona (Spain). E-mail: [email protected] Polyoxometalates (POMs) are metal oxide clusters build up from single metal oxide units (usually Mo, W, V or Nb), that can also contain non metallic oxide units (Al, Si, P or S among others). The synthesis of POMs occurs in homogeneous media, so their field of application is usually related with chemistry in solution. One of the interesting properties of POMs is that POMs are reservoir of electrons and they can be easily reduced under mild conditions. [1] These properties have attracted the attention of scientists in fields like heterogeneous catalysis and material science. By means of immobilizing POMs on a surface or on a matrix, it has been possible to develop new materials with interesting properties such as constituents in new electrode materials. Concretely, Keita and Nadjo used POMs for tunning the properties of several electrodes used in the Hydrogen Evolution Reaction (HER), but it was not until the late nineties that Gewirth and co-workers showed how POMs are linked on these electrode surfaces. [2] From a theoretical point of view, POMs in solution have been vast studied in the last decade, but the study of the interaction between POMs and surfaces is still a challenge. Besides the problems that the size and the high charge of POMs involve, it is well known that solvent and counterions are compulsory for a good description of the electronic structure of the system. How can we introduce these effects in a system that is intrinsically periodic? Here we present a general strategy to model the adsorption of POMs on surfaces by combining periodic DFT methods with classical MD methods so as to include the solvent and the couterions. We start with the discussion of the spontaneous reduction of α-[SiW12O40]4- on Ag(100) comparing experimental and theoretical data, mostly concerned on correctly place the Fermi Level of the system.[3] Afterwards, we present the results obtained for several POMs adsorbed on different surfaces using the same strategy.

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Microsymposia

Microsymposia

[1] D. E. Katsoulis, Chem. Rev., 1998, 98, 359-387. [2] M. H. Ge, B. X. Zhong, W. G. Klemperer, A. A. Gewirth, J. Am. Chem. Soc., 1996, 118, 5812-5813. [3] X. Aparicio-Anglès, P. Miró, A. Clotet, C. Bo, J.M. Poblet, Chem. Sci., 2012, DOI: 10.1039/C2SC20210G

Keywords: Polyoxometalate, Surfaces, DFT

[1] S. Reinoso, Dalton Trans., 2011, 40, 6610-6615. [2] S. Reinoso, J. R. Galán-Mascarós, Inorg. Chem., 2010, 49, 377-379. [3] S. Reinoso, J. R. GalánMascarós, L. Lezama, Inorg. Chem., 2011, 50, 9587-9593. [4] Y. Hou, L. Xu, M. J. Cichon, S. Lense, K. I. Hardcastle, C. L. Hill, Inorg. Chem., 2010, 49, 4125-4132.

Keywords: polyoxotungstates, cobalt, cerium

MS.B2.C.04 Heterometallic Weakley-Like Tungstogermanate with {Ce2Co2} Rhomblike Core Santiago Reinoso, Leire San Felices, Luis Lezama, Beñat Artetxe, Amaia Iturrospe, Aroa Pache, Juan M. Gutiérrez-Zorrilla, Departamento de Química Inorgánica, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV/EHU, Bilbao (Spain). E-mail: santiago.reinoso@ ehu.es Combination of lacunary polyoxometalates (POMs) and 3d or 4f metals constitutes a powerful tool for designing complex POM architectures, and at the same time, introducing new properties (magnetism, additional catalytic centres). Thus, 3d-substituted and 4f-containing POMs have become two of the largest and most extensively studied groups among the vast POM family. In contrast, the field of heterometallic 3d-4f POMs is still slowly emerging [1] and almost all reported species can be considered as “isolated” examples, that is, there is a lack of heterometallic POM series showing systematic compositional variations for reactivity or properties to be adequately compared. Recently, we reported that interaction of CeIV with Weakleytype [(3dII)4(H2O)2(GeW9O34)2]12– POMs (3d = Mn, Cu) results in heterometallic derivatives with {(CeIII)2(MnIII)2} [2] or {(CeIV)(CuII)3} [3] cores. Extension of this work to Ge-precursors with other 3d metals like Co or Ni was however hindered by the fact that no straightforward syntheses under bench conditions are available as for the Mn or Cu ones. Here we report a new synthetic method for the [Co4(H2O)2(B-aGeW9O34)2]12– precursor and its interaction with CeIV, which results in the [{Ce(H2O)2}2Co2(B-a-GeW9O34)2]8– heterometallic species. The ββ-tetrasubstituted precursor has been obtained by a slight modification of Hill’s procedure for preparing the related 3d-disubstituted phosphotungstate species [4], which has showed to be also applicable for the complete series of divalent 3d metals. The heterometallic derivative is the cobalt analogue of our previous {Ce2Mn2} cluster and it can be described as a Co-disubstituted Weakley-type tungstogermanate subunit with αα-configuration stabilized by two {Ce(H2O)2} moieties. According to its EPR spectrum, both metals in the central {Ce2Co2O20} rhomblike cluster are in the +3 oxidation state, thus representing one of the scarce examples of a CoIII-containing POM and indicating that systematic compositional modifications could be performed in this type of frameworks.

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MS.B2.C.05 Theoretical Study of Magnetic Properties of Reduced Polyoxometalates Suaud Nicolasa, Guihéry Nathaliea, Clemente-Juan Juan-Modestob, Coronado Eugeniob, Gaita-Arino Alejandrob, Cadot Emmanuelc, Mialane Pierrec, aLaboratoire de Chimie et Physique Quantiques, Université Paul Sabatier, Toulouse (France); aInstitute for Molecular Science, University of Valencia, Valencia (Spain); cInstitut Lavoisier, Université de Versailles, Versailles (France). E-mail: suaud@irsamc. ups-tlse.fr I will present a theoretical two-step approach for determining magnetic properties of reduced POM and its application in two cases. The first step consists in Wave-Function calculations performed on embedded fragments of POM to obtain accurate evaluations of the main microscopic interactions of the delocalized electrons: electron transfer and magnetic coupling between nearest-neighbours metal centres, electrostatic repulsion and orbital energy. In a second step, these parameters are introduced in a model Hamiltonian well suited to reproduce the magnetic properties of the whole POM. I will then present how this methodology succeeded to explain the origin of a surprisingly strong magnetic coupling in the 4-electronreduced V4Mo8 Keggin-type POM. Finally, I will show how this approach was used as a predictive tool for studying the impact of an electric field on the magnetic properties of the 2-electron-reduced V14 ion. A very abrupt parato-antiferro magnetic transition is expected, a feature relevant for quantum computing. Keywords: Polyoxometalates, Magnetic properties, Theoretical approach

MS.B2.C.06 Tuning Reductive Aggregation for Polyoxometalate-Based Molecular Nanoscience R. John Errington,a Gavin Harle,a Balamurugan Kandasamy,a Paul S. Middleton,a aSchool of Chemistry, Newcastle University, Newcastle upon Tyne, (UK). E-mail: [email protected]

Microsymposia allows the preparation of smart materials that include POMs. Different synthetic procedures and the characterization of the POM-polymer hybrids will be presented. We grafted poly-diethylacrylamide on a Dawson-type polyoxotungstate. The hybrid compound exhibits thermoresponsive properties in aqueous solution. Above the lower critical solution temperature of 39°C, it forms reversibly aggregates in the range of 100 nm. The properties can be tuned by variation of the polymer length and the counterion. [3]

Self-assembled structure from functionalized Lindqvist polyoxovanadates [V6O13{(OCH2)3CNHCOpyr}2]2– and [PdCl2]. [1] M. P. Santoni, A. K. Pal, G. S. Hanan, A. Proust, B. Hasenknopf, Inorg. Chem. 2011, 50, 6737. [2] M.-P. Santoni, A. K. Pal, G. S. Hanan, M.-C. Tang, K. Venne, A. Furtos, P. Menard-Tremblay, C. Malveau, B. Hasenknopf, Chem. Commun. 2012, 48, 200. [3] J. Rieger, T. Antoun, S.-H. Lee, M. Chenal, G. Pembouong, J. Lesage de la Haye, I. Azcarate, B. Hasenknopf, E. Lacôte, Chem. Eur. J. 2012, 18, 3355.

Keywords: self-assembly, smart materials, polyoxometalates

[1] R. Bakri, A. Booth, G. Harle, P. S. Middleton, C. Wills, W. Clegg, R. W. Harrington and R. J. Errington, Chem. Comm. 2012, 48, 2779. [2] J. Lehmann, A. Gaita-Ariño, E. Coronado and D. Loss, J. Mater. Chem. 2009, 19, 1672; J. Lehmann, A. Gaita- Ariño, E. Coronado and D. Loss, Nature Nano. 2007, 2, 312.

Keywords: polyoxometalate, reduction, assembly

MS.B2.C.07 Ligand-induced Self-Assembly of Polyoxometalates Bernold Hasenknopf, UPMC-Sorbonne Universités, Institut Parisien de Chimie Moléculaire, Paris, France. E-mail: bernold.hasenknopf@ upmc.fr Supramolecular chemistry has established the concepts for the self-assembly of complex architectures and smart materials. Organic molecules are often determining the outcome of such processes. Therefore, the attachment of POMs to suitable organic molecules yields organic-inorganic hybrids that are useful constituents for the incorporation of POMs into supramolecular systems. This presentation focuses on two different approaches: i) The grafting of ligands with free binding sites allows the self-assembly of supramolecular architectures through the coordination of transition metals. The general principle, the hurdles and the final assembly of a trimeric macrocycle will be presented. We have grafted pyridyl, bipyridyl and terpyridyl type ligands on different POM platforms (Anderson, Lindqvist and Dawson-type).[1] The geometric constrains imposed by the coordination vectors of these ligands determine the outcome of metal complexation, such as coordination polymers or discrete species.[2] ii) The grafting of thermoresponsive polymers

MS.B2.C.08 Understanding the Structure and Properties of Uranyl Peroxide Nanocapsules Carles Bo,a,b Adrià Gil,a Pere Miró,a aInstitute of Chemical Research of Catalonia, ICIQ, Tarragona (Spain). bUniversitat Rovira i Virgili, Tarragona (Spain). E-mail: [email protected] During the last decade, the chemistry of polyoxometalates (POMs) enabled growing impressive new giant molecular metal oxide nanostructures. In some cases, the shape of the POM framework is such that it forms inner cavities, which are usually filled with other molecular species. In other cases, the cations used in their synthesis have a strong influence on the formation of some building blocks, which self-assemble a posteriori. These two characteristics are found in a new class of POMs, the uranyl peroxide clusters or polyperoxouranates discovered just a few years ago [1, 2]. The basic building blocks of these POMs are uranyl (UO2)-peroxide bridged macrocycles of either four, five or six uranyl units linked by peroxo ligands. By considering small clusters such as [UO2(O2)(H2O)]n (n=4, 5, 6) and DFT based methods, we found that the stability of macrocyclemonovalent cation (from Li+ to Cs+) complexes suggests that the origin for the cation templated formation of uranyl-peroxide building-blocks is the distinct affinity of the macrocycles for the cations [3]. Similar effects were observed in the U20 capsule, [M12(UO2)20(O2)30]8- [4]. U28, [(A12B4)(UO2(O2)1.5)28]12- (A=K+, Na+; B=K+, Rb+ and Cs+) encapsulates M(O2)43- (M=Ta, Nb) and other U and V species. The full structure of the guest could not be fully solved because crystallographic disorder. Computed structures agree well with X-ray data, and explain the disorder as well as cation exchange experiments. The analysis of the electronic structure, in particular the nature of the LUMO band, enable understanding the electrochemical properties of these species [5].

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The use of polyoxometalates (POMs) as either individual functional units in molecular devices or as molecular building blocks for the construction of new nanoscale materials requires precise control of the chemistry involved in POM synthesis and in any subsequent assembly processes. We are addressing this major challenge in POM chemistry, and an approach will be described which involves the controlled chemical reduction of the phosphomolybdate Keggin anion [PMo12O40]3–, which effectively increases the surface basicity of this POM, and reactions with electrophiles to give capped species [PMo12O40{MLn}x]z–. This strategy provides a generic platform for the manipulation of a wide range of electron-rich POMs. To illustrate the versatility of this approach to reductive aggregation, examples will be described with different levels of core reduction and different capping groups, including two-electron-reduced monocapped species [PMo12O40{M(MeCN)2}]3– (M = Co, Zn), the sixelectron-reduced [PMo12O40Sb2]3– and the four-, five- or six-electronreduced di-capped vanadyl derivatives [PMo12O40(VO)2]z–, where the change in spin coupling between vanadyl groups with the redox state of the core has been proposed as a means of producing molecular spin valves. [1, 2] Issues regarding the redox properties of these capped POMs will be discussed, including the dissociation of capping groups upon oxidation, and the feasibility of controlling the solution assembly of extended electron-rich POM-based materials by careful selection of capping groups and ligands will be highlighted.

Microsymposia [1] E. Cadot, M.-A. Pilette, J. Marrot, F. Sécheresse Angew. Chem. Int. Ed. 2003, 42, 2173-2176. [2] M. N. Sokolov, I. V. Kalinina, E. V. Peresypkina, E. Cadot, S. V. Tkachev, V. P. Fedin, Angew. Chem. Int. Ed. 2008. [3] J. Marrot, M.-A. Pilette, M. Haouas, S. Floquet, F. Taulelle, X. López, J. M. Poblet, E. Cadot, J. Am. Chem. Soc., 2012, 134, 1724–1737. [4] C. Shäffer, ; A. M. Todea, H. Bögge, E. Cadot, G. Gouzerh,S. Kopilevich,I. A. Weinstock, A. Müller, Angew. Chem. Int. Ed. 2011, 50, 12326.

Keywords: polyoxometalate, sulphur, supramolecular chemistry

MS.B2.C.10 Chromatographic Characterization of Molybdenum-Blue Solution Using Gel-Electrophoresis Ryo Tsunashima,a Ippei Nakamura,a Katsuya Ishiguroa, Leroy Cronin,b a Graduate School of Science and Engineering, Yamaguchi University,Yamaguchi (Japan). Department of Chemistry, University of Glasgow, Glasgow (UK). E-mail: [email protected] [1] P. C. Burns, K.-A. Kubatko, G. Sigmon, B. J. Fryer, J. E. Gagnon, M. R. Antonio and L. Soderholm, Angew. Chem., Int. Ed., 2005, 44, 2135-2139. [2] T. Z. Forbes, J. G. McAlpin, R. Murphy and P. C. Burns, Angew. Chem., Int. Ed., 2008, 47, 2824-2827. [3] P. Miro, S. Pierrefixe, M. Gicquel, A. Gil and C. Bo, J. Am. Chem. Soc., 2010, 132, 17787-17794. [4] P. Miro and C. Bo, Inorg. Chem., 2012, 51, 3840-3845. [5] A. Gil, D. Karhánek, P. Miró, M. R. Antonio, M. Nyman and C. Bo, Chem. Eur. J., 2012, DOI: 10.1002/chem201200801.

Keywords: Polyoxometalates, nanocapsules, DFT

MS.B2.C.09 Supramolecular Panelling From {Mo2O2S2} Coordination Emmanuel Cadot, Sébastien Floquet and Nathalie Leclerc, a Institut Lavoisier de Versailles, University of Versailles Saint Quentin,Versailles, (France). E-mail: [email protected] Softening of polyoxometalates through inclusion of sulfido groups within the {MxOy} framework [1,2] is expected to modify significantly the POM properties e.g. structural and electronic, and thereby appear be an “ideal” strategy to associate and cumulate complementary properties at the molecular level, such as the electrocatalytic function of the {M-S} core combined with the electrons storage capacity of the polyoxometalate. We will report on the synthetic approaches for the formation of the literally “polyoxothiometalate” compounds with special emphasis on the unique reactivity of the preformed sulphur-containing cationic building blocks {Mo2O2S2}2+ and {Mo3S4}4+ toward polyoxometalate building blocks. Such simple systems, based on chemical and structural complementarities between ionic reactive moieties have allowed producing a series of relevant clusters with unrivalled large nuclearity structural arrangements, like rings, triangles, squares and boxes.[3,4] Specific reaction parameters and considerations will be pointed out showing that a deliberate pure inorganic supramolecular chemistry based on weak interactions, flexibility and dynamic is possible with polyoxometalates.

Polyoxometalates (POMs) are polymeric clusters of oxo anions (MOx where M = Mo, W, V, Nb and x = 4–7) that employ wide range of structural morphologies such as capsules, spheres and wheels forming nano-scaled clusters. The structural diversity among POMs can however present a major problem when attempting to discover and characterise unknown clusters, either in the solid state or even more so in solution. This is mainly due to the difficulty in the crystallization of such nanoclusters, especially when they are present as mixture. We have been developed gel-electrophoresis as a technique for conventional chromatography which enables separation and identification of clusters according to their structural types. [1] Since the Mo-brown ball {Mo132} and Mo-blue wheel {Mo154} have very large sizes and charges, these clusters are ideal candidates for investigation by electrophoresis. Fig. 1 shows pictures of the gel during electrophoresis taken at 0, 6 and 10 min. This shows that both POMs moved toward the anode with different mobilities. In this report, we focused on molybdenum-blue (MB). Since the various crystalline species have been isolated and characterized using single crystal XRD technique, the solutions are still not completely understand. Here, MB reactions were monitored using chromatographic gel-electrophoresis and their products were structurally characterized. Further details related to formation process will be discussed.

Fig. 1. Photographs of a gel for electrophoretic separation of molybdenum blue and molybdenum brown taken at 0, 6 and 10 min intervals during the run. Each column is: (left) {Mo132}; (middle) 1 : 1 mixture of {Mo132} and {Mo154}; and (right) {Mo154}, all at 2.0 mM concentrations.

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Microsymposia [1] R. Tsunashima, C. Richmond, L. Cronin, Chem. Sci., 2012, 3, 343-348.

Keywords: polyoxometalate

MS.B2.C.11

[1] H. Wang, S. Hamada, Y. Nishimo, S. Irle, T. Yokoyama, H. Yoshikawa, K. Awaga, J. Am. Chem. Soc., 2012, 134, 4918–4924. [2] Q. Yin, J.M. Tan, C. Besson, Y.V. Geletii, D.G. Musaev, A.E. Kuznetsov, Z. Luo, K.I. Hardcastle, C.L. Hill, Science, 2010, 328, 342-345.

Keywords: polyoxometalates, electrochemistry, DFT

Theoretical Study on the Electrochemistry of Iron-containing Wells-Dawson Complexes Pablo A. Aparicio, Xavier López, Josep M. Poblet, Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Tarragona, (Spain). E-mail: [email protected]

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Polyoxometalates (POMs) are versatile molecular metal-oxygen clusters with applications in catalysis, magnetism, medicine and materials science. During the past years, POMs with new physical properties have been developed, such as electron storages in redox processes [1]. Indeed, they may behave as donors or as acceptors in reversible electron transfer processes. Therefore, understanding the mechanisms that govern these electron transfers has become a main subject in POM science. It has been recurrently proven that density functional theory (DFT) gives reliable structures and energies with moderate computational effort. For this reason, most of the computational papers studying POMs are based on these DFT calculations. The study of the electrochemistry of POMs has been performed since the 60’s by Pope and co-workers. The extensive attention given to the redox properties of POMs has revealed a singular and unexpected behaviour, which cannot be explained by electrochemistry alone. Herein DFT calculations have led to a better understanding of the properties of POMs. The species derived from vacant Wells-Dawson fragments are of great interest. We herein focus on the study of monosubstituted and sandwich-type Wells-Dawson complexes (Figure 1). One of the most important applications of sandwich-type POMs is homogeneous catalysis. Hence, Hill and co-workers have recently developed a new viable water oxidation catalyst [2]. We have performed a study of different Wells-Dawson structures where one or more W has been substituted by Fe. The unusual redox behaviour displayed by the two isomers of the Wells-Dawson phosphotungstate anion [Fe(H2O) P2W17O61]7- is analysed. The electrochemistry of mixed Fe-M-containing Wells-Dawson sandwich-type complexes, [Fe2(OH2)2M2X4W30O112]14and [M2(OH2)2Fe2X4W30O112]14-, with different metal atoms (M) and X = As or P has been also performed.

Figure 1. Polyhedral and ball and stick representation of metal-iron WellsDawson sandwich-type complexes.

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9 - 13 September 2012

Microsymposia

Nanoelectronics Molecular metal Wires and Related Molecular Materials Shie-Ming Peng, Institute of Chemistry, Academia Sinica, Taipei, Taiwan Department of Chemistry, National Taiwan University, Taipei, Taiwan. E-mail: [email protected] We have designed a series of new ligands such as oligo-αpyridylamines, and used them to construct an unique class of quadruple helix of metal strings. This achievement leads to a new direction to the application of molecular wires in the nanoelectronics. The outline is as follows: I. Linear Metal String Complexes [1-3]. Synthesis, Structure, Bonding.

II. Potential Application as Molecular Metal Wires & Molecular Switches [4]. STM Study on the Conductivity of Metal Strings. C-AFM Measurements of Single Metal String Molecules. Comparative Study on the I-V Characterisics (Theory V.S. Experiment). III. Tuning of the Metal Strings [5-8]. Naphthyridyl Amino Ligands: Low Oxidation Mixed Metal Strings. Asymmetrical Ligands: Toward Molecular Rectifier. Heteronuclear Metal String Complexes. IV. Conclusion. [1] C.-Y. Yeh, C.-C. Wang, Y.-H. Chen and S.-M. Peng, in Redox Systems Under Nano-Space Control, Ed: T, Hirao, Springer, Germany 2006, Ch. 5. [2] S.-Y. Lai, T.-W. Lin, Y.-H. Chen, C.-C. Wang, G.-H. Lee, M.-H. Yang, M.-K. Leung and S.-M. Peng, J. Am. Chem. Soc. 1999, 121, 250. [3] S.-J. Shieh, C.-C. Chou, G.-H. Lee, C.-C. Wang and S.-M. Peng, Angew. Chem. Int. Ed. Engl., 1997, 36, 56. [4] I.-W. P. Chen, M.-D. Fu, W.-H. Tseng, J.-Y. Yu, S.-H. Wu, C.-J. Ku, C.-H. Chen, and S.-M. Peng, Angew. Chem. Int. Ed. Engl. 2006, 5414. [5] (a) C.-H. Chien, J.-C. Chang, C.-Y. Yeh, G.-H. Lee, J.-M. Fang and S.-M. Peng, Dalton Trans. 2006, 2106. (b) C.-H. Chien, G.-H. Lee, Y. Song and S.-M. Peng, Dalton Trans. 2006, 3249. [6] M.-M. Rohmer, I. P.-C. Liu, J.-C. Lin, M.-J. Chiu, C.-H. Lee, G.-H. Lee, M. Benard, X. Lopez, S.-M. Peng, Angew. Chem. Int. Ed. Engl. 2007, 46, 3533. [7] I. P.-C. Li, W.-Z. Wang, and S.-M. Peng, Chem. Commun. 2009, 4323-4331. [8] R. H. Ismayilov, W.-Z.Wang, G. H. Lee, C. Y. Yeh, S. A. Hua, Y. Song, M. M. Rohmer, M. Bénard, S.-M. Peng, Angew. Chem. Int. Ed., 2011, 50, 2045-2048.

MS.B3.KN2 Spin State Switching in Homogeneous Solution and on Surfaces: Experimental and Theoretical Results F.Tuczek, Institut für Anorganische Chemie, Christian-AlbrechtsUniversität, Kiel, Germany. E-mail: [email protected]

central ion have been determined. The experimental data are compared with DFT calculations of the complexes in their high spin and low spin states, respectively.[1] The results obtained on iron complexes are compared with data obtained on Ni(II) porphyrin complexes coordinated with analogous ligands,[2,3,4] in which a change in the coordination number is employed to change the spin state of the central ion (CISSS and LD-CISSS, respectively). The Fe and Ni complexes have also been attached to surfaces and investigated with IRRAS, XPS, NEXAFS, and STM. In addition, thin films of the iron complexes [FeII(H2Bpz)2(phen)] and [FeII(H2Bpz)2­(bipy)] have been prepared by vacuum deposition and investigated with respect to their spin crossover behaviour (H2Bpz = bis(pyrazolyl)borate).[5] For the first time light-induced excited spin state trapping (LIESST) has been observed in such systems. T1/2 and TLIESST in the films have been found to be in agreement with the bulk values. In double layers of these complexes on Au(111) spin-state switching on the single-molecule level has been observed.[6] The implications of these findings on the area of spintronics are discussed. Funding of this research by DFG (SFB 677) is gratefully acknowledged. [1] A. Bannwarth, S.-O. Schmidt, G. Peters, W. Thimm, R. Herges, F. Tuczek. Eur. J. Inorg. Chem. 2012, 2776–2783. [2] S. Thies, C. Bornholdt, F. Köhler, F. D. Sönnichsen, C. Näther, F.Tuczek, R. Herges Chem. Eur. J. 16, 16, 9928-9937 (2010). [3] S. Venkataramani, U. Jana, M.Dommaschk, F. D. Sönnichsen, F.Tuczek, R. Herges Science 331, 445-448 (2011). [4] S. Thies, C. Bornholdt, C. Näther, F. Tuczek, R. Herges J.Am.Chem.Soc. 133, 16243–16250 (2011). [5] H. Naggert, A. Bannwarth, S. Chemnitz, Th. v. Hofe, E. Quandt, F.Tuczek Dalton Trans. 40, 6364-6366 (2011). [6] T. G. Gopakumar, F. Matino, H. Naggert, A. Bannwarth, F. Tuczek and R. Berndt Angew. Chem. Int. Ed. 51(25), 6262 (2012).

MS.B3.KN3 Supramolecular Quantum Spintronics Mario Ruben,a,b aInstitute Nanotechnology, KIT, Karlsruhe (Germany). b IPCMS, Université de Strasbourg, Strasbourg (France). E-mail: [email protected]; www.ruben-group.de Magnetic molecules have recently attracted interest in view of their potential to realize nanometre-sized (single)molecular spintronic devices by a combination of bottom-up self-assembly and top-down lithography techniques. We report herein on the controlled generation of magnetic molecular nanostructures on conducting surfaces, partially self-assembled on sp2-carbon nano-structures (SW-CNTs, graphene), or between nano-gap gold electrodes. The obtained supramolecular devices are investigated in view of their I-V-characteristics by means of UHV- and solution-based scanning probe, break junction and electromigration techniques. [1-5] [1] S. Klyatskaya, J. R. Galan Mascaros, L. Bogani, F. Hennrich, M. Kappes, W. Wernsdorfer, M. Ruben, J. Am. Chem. Soc. 2009, 15143-15151. [2]. M. Marschall, J. Reichert, A. Weber-Bargioni, K. Seufert, W. Auwärter, S. Klyatskaya, G. Zappellaro, M. Ruben, J. V. Barth, Nature Chem. 2010, 2, 131 – 137. [3]M. Urdampilleta, S. Klyatskaya, M.-P. Cleuziou, M. Ruben, W. Wernsdorfer, Nature Mater. 2011, 10, 502-506. [4] J. Schwöbel, Y. Fu, J. Brede, A. Dilullo, G. Hoffmann, S. Klyatskaya, M. Ruben, R. Wiesendanger, Nature Comms. 2, 2012, DOI:10.1038/ncomms1953. [5] R. Vincent, S. Klyatskaya, M. Ruben, W. Wernsdorfer, F. Balestro Nature 2012, in press.

Keywords: Surface-Confined Coordination Supramolecular Devices, Molecular Spintronics

Chemistry,

The switching behaviour of Fe(II) and Fe(III) complexes coordinated by photoswitchable phenylazopyridine ligands has been investigated, and the consequences of the trans ↔ cis photoisomerization of the coordinated ligands with respect to the magnetic properties of the

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MS.B3.KN1

Microsymposia MS.B3.I1 Unconventional lithographic processing of coordination compounds for organic electronic Massimiliano Cavallinia, CNR-Istituto per lo Studio dei Materiali Nanostrutturati (ISMN) Via P. Gobetti 101, 40121 Bologna, Italy. E-mail: [email protected] Organic field effect transistors have been widely used for investigating charge transport and injection in organic semiconductors. As their performance and stability have considerably improved in the last years, there is a growing interest in their application in allorganic active matrix displays, logic elements, organic light emitting transistors and sensors. All these applications rely on the precise control of the interfaces, the morphology of the film and the structure of the active layers. On the other hand their simultaneous control may not be trivial to achieve with thin film deposition techniques, where competition between 2D and 3D nucleation, growth transitions, dewetting, and recrystallisation can interfere with the control of interfacial morphology. Here we demonstrate several new architecture for unipolar[1] and ambipolar[2] devices, based on the lithographic manipulation of organic and hybrid multifunctional materials. With this aim we present the application of some wet lithographic methods[3] able to exploit self-organising properties of functional materials in controlled manner[4], obtaining nanostructure with improved charge mobility. [1] Cavallini, M.; Stoliar, P.; Moulin, J. F.; Surin, M.; Leclere, P.; Lazzaroni, R.; Breiby, D. W.; Andreasen, J. W.; Nielsen, M. M.; Sonar, P.; Grimsdale, A. C.; Mullen, K.; Biscarini, F., Nano Lett. 2005, 5 (12), 2422-2425. [2] M. Cavallini; P D’Angelo; V. Vendrell Criado; D. Gentili; A. Shehu; F. Leonardi; S. Milita; Liscio, F.; Biscarini., F., Adv. Mater. 2011, 23, 5091–5097. [3] Cavallini, M.; Albonetti, C.; Biscarini, F., Adv. Mater. 2009, 21, 1043-1053. [4] Cavallini, M. J. Mater. Chem. 2009, 19 (34), 6085-6092.

Keywords: Organic field effect transistors, wet lithography, controlled self-assembly

MS.B3.I2 Controlling the Surface Growth of Metal-Organic Frameworks with Tip-Based Nanolithography Daniel Maspoch,a, bCarlos Carbonell,a Kyriakos Stylianou,a Inhar Imaz,a aCIN2 (ICN-CSIC), Catalan Institute of Nanotechnology, Campus UAB, Bellaterra, (Spain). bInstitució Catalana de Recerca i Estudis Avançats (ICREA), 08100 Barcelona, (Spain). E-mail: daniel. [email protected] The high surface areas and tunable composition and porosity of Metal-Organic Frameworks (MOFs) have opened up many new application opportunities in different industrial fields. Already present in areas such as gas storage, separation, and catalysis, MOFs are in constant evolution and continuously confronting new challenges. One of these major current challenges is their integration on surfaces for the fabrication of surface sensors, electronic devices, catalytic platforms, etc.[1] In this talk, I will show how the versatile Tip-Based Nanolithography (TBN) can be used in order to control not only the growth but also the position of MOF crystals on surfaces. TBN such as Dip-Pen Nanolithography, Fluidic Enhanced Molecular Transfer Operation and Fountain-Pen Lithography allow transferring desired MOF precursors on surfaces at the nanometer length scale through a SPM probe or cantilever that dispenses femtoliter droplets of a solution containing these species. Once these droplets are positioned on the surface, the formation and crystallization of MOFs can be confined in each deposited droplet by controlling its evaporation and/or using

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external conditions, such as microwave radiation or high temperatures. Following this strategy, herein I will show the controlled crystallization of different MOFs on supports, even at the single-crystal level,[2] as well as the possibility to control more complex reactions on surfaces to generate combinatorial MOF arrays.

[1] A. Carné, C. Carbonell, I. Imaz, D. Maspoch, Chem. Soc. Rev., 2011, 40, 291–305. [2] C. Carbonell, I. Imaz, D. Maspoch, J. Am. Chem. Soc., 2011, 133, 2144–2147.

Keywords: Metal-Organic Nanolithography, MOF arrays

Frameworks,

Tip-based

MS.B3.I3 1D nanomaterials synthesis using a biopolymer template Andrew Houlton, Chemical Nanoscience Laboratory, School of Chemistry, Newcastle University, Newcastle upon Tyne, NE1 7RU, (U.K). E-mail: [email protected] The controlled preparation and assembly of opto-electronic materials at nanoscale lengths is being tackled by top-down and bottom-up approaches.[1] The latter method draws inspiration from biology, where complex systems are assembled from simpler building blocks. One of these building blocks, DNA (Figure), is proving especially useful in this regard: Its size, topology, the assorted chemical functional groups, plus its capacity for self-assembly provide a powerful nanoscale toolbox for materials preparation.[2] Here, some aspects of our research on DNA-based nanomaterials will be presented which demonstrates that the growth of both hard and soft materials can be controlled using the biopolymer as a template. The diverse range of bonding interactions, from coordinate to supramolecular, are exploited between precursors and DNA in order to control the material growth. Examples are provided for different material types which can include metals,[3,4] binary inorganics[5] and polymer-based semiconductors.[4,6-9] The preparation method has an important effect on the resulting materials which can have either a beads-on-a-string or a continuous wire-like morphology. In the latter case the resulting nanowires can be used a components in simple electrical devices (Figure) and may also function as chemical sensors.[10] Interestingly, DNA/conjugated polymer nanowires have been found in some cases to have enhanced conductivities compared to bulk,[6] undergo further self-assembly forming highly regular ropelike structures[7] and can also enhance the growth of metals when appropriately functionalised.[4]

Microsymposia carriers, leading to an n-type behavior. We used complementary techniques such as Electron Paramagnetic Resonance, absorption spectroscopy and photoluminescence to ensure the success of the assembly process and the integrity of the complex in the nanohybrid. We carried Density Functional Theory type calculations to rationalize the experimental results evidencing the selective enhanced interaction of the metal complexes with one type of nanotube.

[1] G. A.Ozin, A. C. Arsenault, Nanochemistry: A Chemical Approach to Nanomaterials; RCS: Cambridge, 2005. [2] A. Houlton, A.R. Pike, M.A. Galindo, B.R. Horrocks, Chem. Commun. 2009, 1797-1806. [3] S. M. D. Watson, N.G. Wright, B. R. Horrocks, A. Houlton, Langmuir 2010, 26, 20682075. [4] S. A. F. Al-Said, R. Hassanien, J. Hannant, M.A. Galindo, S. Pruneanu, A.R. Pike, A. Houlton, B. R. Horrocks, Electrochem. Comm. 2009, 11, 550-553. [5] L. Dong, T. Hollis, B.A. Connolly, N.G. Wright, B.R. Horrocks, A. Houlton, Adv. Mater. 2007, 19, 1748-1751. [6] L. Dong, T. Hollis, S. Fishwick, B.A. Connolly, N.G. Wright, B.R. Horrocks, A. Houlton, Chemistry Eur. J. 2007, 13, 822-828. [7] S. Pruneanu, S.A.F. Al-Said, L. Dong, T. Hollis, M.A. Galindo, N.G. Wright, A. Houlton, B. R. Horrocks, Adv. Funct. Mater. 2008, 18, 1-12. [8] J. Hannant, J.H. Hedley, J. Pate, A. Walli, S.A.F. Al-Said, M.A. Galindo, B.A. Connolly, B.R. Horrocks, A. Houlton, A.R. Pike, Chem.Commun. 2010, 46, 5870-5872. [9] R. Hassanien, M. Al-Hinai, S.A.F. Al-Said, R. Little, L. Siller, N.G. Wright, A. Houlton, B.R. Horrocks, ACS Nano 2010, 4, 2149-2159. [10] M. Al-Hinai, N.G. Wright, A. Horsfall, R. Hassanien B. R. Horrocks, A. Houlton, IEEE Sensors, 2011, 1-4.

Keywords: DNA, templating, nanowires

MS.B3.I4 Transport behavior of complexes assembled on Carbon Nanotube FET devices Talal Mallah,a Gurvan Magadur,a Jean-Sébastien Lauret,b Gaëlle Charron,a Fatima Bouanis,a,c Evgeny Norman,c Vincent Huc,a CosteSorin Cojocaru,c Silvia Gómez-Coca,d Eliseo Ruiz,d Ally Aukauloo,a a Institut de Chimie Moléculaire et des Métériaux d’Orsay, (France). b Laboratoire de Photonique Quantique et Moléculaire, ENS-Cachan, (France). cLaboratoire de Physique des Interfaces et Couches Minces, Ecole Polytechnique, (France). dDepartment of Inorganic Chemistry, University of Barcelona, Barcelona (Spain). E-mail: [email protected] The assembly of paramagnetic Cu2 complexes with a Schiff base scaffold possessing extended electron delocalization together with a quasi-planar structure onto carbon nanotubes induces a diameter selective electron transfer from the complex to the nanotubes leading to an interestingly large and tunable ambipolar effect observed in ambient air conditions.[1] The magnitude of the electron transfer and the ambipolar effect were found to be directly related to the concentration of the molecules on the nanotube (Figure 1), this is an evidence that the observed behavior is indeed due to an electronic interaction between the assembled complexes and the nanotubes and not to other electrical phenomena indirectly induced by the molecules. The origin of the ambipolar behavior can be understood by the following: as VGate becomes positive, the conduction band of the nanotubes is bending toward lower energies, thus being able to receive electrons from the HOMO of the molecules; the electrons then become the main charge

MSB3

Figure. Molecular structure of a DNA duplex used for templating of materials and (right) a single DNA/CdS nanowire device.

Figure 1. Ids vs. Vg curves for a CNFET device before (black curve) and after a different number of grafting-rinsing cycles with the Cu2 complex. The experimental starting gate potential is - 20 V and the evolution of the current is given by the black arrows on the black curve. [1] G. Magadur, J.-S. Lauret, G. Charron, F. Bouanis, E. Norman, V. Huc, C.S. Cojocaru, S. Gómez-Coca, E. Ruiz, T. Mallah, J. Am. Chem. Soc. 2012, accepted.

Keywords: nanotubes, CNFET, Cu2 Schiff base

MS.B3.I5 Multiple Noninterfering Dynamic Coordination in Self-Assembly and Poly-Nanocages Michael Schmittel, Kingsuk Mahata, Jian Fan, Manik Lal Saha, Holger Schönherr, Bo Song, Center of Micro and Nanochemistry, Department of Chemistry and Biology, Universität Siegen, Siegen (Germany). E-mail: [email protected] The use of several dynamically operating coordination motifs in an orthogonal, non-interfering complexation scenario requires to establish rigorous self-sorting protocols. In our approach, we amalgamate all members of an intricate library of metal ions and ligands in a single multicomponent aggregate employing completive and integrative selfsorting. As an example, we will first present the self-assembly of a dynamic bimetallic trapezoid from a 6-component A1A2D1D2D3D4 (A =acceptor, D =donor) library.[1] Extending the above conceptual insights to self-sorting in an 8-component A1A2A3D1D2D3D4D5 library (see below), we will detail the fabrication of a dynamic trisheterometallic scalene triangle,[2] a demanding and unprece­dented supramolecular structure.

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Dynamic orthogonal coordination motifs may further find use in affording new polymer structures, such as star polymers with arms of equal length. In this context, we will describe the use of a metallosupramolecular prismatic nanocage with altogether six reactive aldehyde terminals as a sophisticated ‘monomer’ in a templatedirected constitutional dynamic imine polymerization to prepare an unprecedented triple-stranded dynamer. To analyze the correlated growth in its three congener strands, a fully covalent triple-armed star polymer was fabricated from the metallodynamer through capping, imine reduction and removal of the template. AFM analysis of 68 triple-armed star polymer molecules suggests that the growth of their arms is correlated to ca. 72%.[3]

[1] K. Mahata, M. Schmittel, J. Am. Chem. Soc. 2009, 131, 16544-16554. [2] K. Mahata, M. Lal Saha, M. Schmittel, J. Am. Chem. Soc. 2010, 132, 15933– 15935. [3] J. Fan, M. L. Saha, B. Song, H. Schönherr, M. Schmittel, J. Am. Chem. Soc. 2012, 134, 150–153.

Keywords: self-sorting, nanoassemblies, heteroleptic

MS.B3.C.01 Coordination Programming of Electro-functional Molecular Wires on the Surface Ryota Sakamoto, Hiroaki Maeda, Shunsuke Katagiri, and Hiroshi Nishihara, Department of Chemistry, Graduate School of Science, The University of Tokyo, (Japan). E-mail: [email protected] The most ultimate goal of molecular electronics is to control electron conduction in molecular wires and networks by combining appropriate molecular units. To evaluate the total performance of the molecular wires, their electron conduction properties of internal molecular segments as well as the resistivity at the electrode-molecular wire junction must be elucidated. We have developed a facile interfacial bottom-up method to fabricate redox molecular wires of bis(terpyridine)metal (M(tpy)2, M

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= Fe, Co) oligomers with the desired number of redox complex units combined with conjugated linkers and with a designed hetero-metal sequence at the gold surface.[1] The electron transport mechanism and kinetics for the redox reaction of the films of linear and branched oligomer wires were analyzed, resulting in the first observation of redox conduction in a single molecular wire in redox polymer films (Figure).[2] Additionally, we have found that the M(tpy)2 oligomer wires show superior long-range electron-transport abilities. The bd value, indicating the attenuation of the electron-transfer rate constant with distance along the molecular wire between the electrode and the redox active species at the terminal of the wire, are 0.008–0.07 Å–1 and 0.002–0.004 Å–1 for molecular wires of Fe(tpy)2 and Co(tpy)2 oligomers, respectively.[3] We also used the stepwise coordination method to construct a system to clarify how the electron transport behavior of molecular wires depends on the surface junction at the molecular level by changing only the surface-anchoring molecular unit. The dependence of the electron transfer rate constant, ket, and the electron transport ability of Fe(tpy)2 oligomer wires on three surfaceanchoring tpy ligands indicate that there is a significant difference in the ket values, which is due to the electronic and steric factors of the surface-anchoring ligands, while the three anchoring ligands give the same bd value.[4] We also investigated the modification of hydrogen-terminated Si(111) surface with redox molecular wires using the hydrosilylation reaction between the Si-H bond and the C≡C bond followed by the interfacial bottom-up method.[5] Electrochemical measurements and AFM observation of the molecular-wire modified Si surface indicate the quantitative growth of the metal complex oligomer wires on the surface.

[1] H. Nishihara, K. Kanaizuka, Y. Nishimori, Y. Yamanoi, Coord. Chem. Rev. 2007, 251, 2674-2687. [2] Y. Nishimori, K. Kanaizuka, M. Murata, H. Nishihara, Chem. Asian J. 2007, 2, 367-376. [3] Y. Nishimori, K. Kanaizuka, T. Kurita, T. Nagatsu, Y. Segawa, F. Toshimitsu, S. Muratsugu, M. Utsuno, S. Kume, M. Murata, H. Nishihara, Chem. Asian J. 2009, 4, 1361-1367. [4] T. Kurita, Y. Nishimori, F. Toishimitsu, S. Muratsugu, S. Kume, H. Nishihara, J. Am. Chem. Soc. 2010, 132, 4524-4525. [5] H. Maeda, R. Sakamoto, Y. Nishimori, J. Sendo, F. Toshimitsu,Y. Yamanoi, H. Nishihara, Chem. Commun. 2011, 47, 8644-8646.

Keywords: long-range electron transfer, electrochemistry, selfassembled monolayers

MS.B3.C.02 Molecular Electronics Based on Self-assembled Multilayer Films Bearing Ru Complex Units Masa-aki Haga,a Takuya Nakabayashi,a Tomoya Joke,b Kazuo Nakazatob, aDepartment of Applied Chemistry, Chuo University, Bunkyo-ku, Tokyo (Japan), bDepartment of Electrical Engineering and Computor Science, Nagoya University, Chikusaku, Nagoya (Japan). E-mail: [email protected] Supramolecular nanostructure toward molecular electronic devices has been paid much attention in recent years. Well-defined multilayer structures, which can be constructed by coordination programming in a rational way, have a potential to build molecular

Microsymposia of the most important subjects in organic materials chemistry because they can exhibit novel electronic and photonic properties as a result of both their discrete dimensions and three dimensional organization. The supramolecular strategies have been also developed to construct nanoassemblies of coordination compounds, such as 1D, 2D, and 3D metal complexes. However, there is no reports on the reversible and hierarchical self-assembly of discrete metal complexes (spincrossover, mixed-valence, magetism and conductivity). In this time we report amphiphilic self-assembled supramolecular nanostructures and functionality for lipid-packaged spin-crossover and mixed valence complexes, [Co(Cn-terpy)2](C12-Glu)2 and [Cn-bifc] (C12-Glu), at first time.

Figure 1. Chemical structure for [Co(Cn-terpy)2](C12-Glu)2, and (a) TEM image for n=15 and (b) TEM image for n=16.

Fig. 1. Structure of molecular unit and the image of multilayer films, and loglog plots of I-V characterisics of the Ru complex layers with different number of layers, n. [1] M. Haga, K. Kobayashi, K. Terada, Coord. Chem. Rev., 2007, 251, 26882701. [2] K. Terada, H. Nakamura, K. Kanaizuka, M. Haga, Y. Asai, T. Ishida, ACS Nano, 2012, 6, 1988-1999.

Keywords: Molecular electronic devices, coordination programing, multilayer films

MS.B3.C.03 Amphiphilic Self-Assembly and Functionality for Lipid-Packaged Metal Complexes Shinya Hayami,a Hidenobu Kamihata,a and Keita Kuroiwab a Department of Chemistry, Kumamoto University, Kumamoto, (Japan). b Department of Nanoscience, Sojo University, Kumamoto (Japan). E-mail: [email protected] The development of new materials based on self-organizing systems has had a great deal of attention due to their potential in the construction of well defined supramolecular nanostructures. Especially, the construction of novel supramolecular architectures with well-defined shape and size by using rod building blocks is one

TEM images for [Co(Cn-terpy)2](C12-Glu)2 (n = 15, 16) were obtained to confirm the detailed supramolecular assembly structures. Helical screw like 1D wire for n = 15 (Figure 1a) and coil formed by rolling up 2D sheet for n = 16 (Figure 1b) were observed. These observations indicate the controllability of self-assembled supramolecular architectures by modulation of the long alkylated metal complexes. Magnetic susceptibilities for [Co(Cn-terpy)2](C12-Glu)2 (n = 15, 16) were also measured in the temperature range of 5 - 400 K. The compounds exhibited gradual spin crossover behaviors. It was demonstrated that the lipidpackaged spin-crossover complexes show morphological changes in dichloromethane solution. Formation of a bilayer structure causes morphological evolution from helical tape to microtube depending on long alkyl chain length of metal complexes. The technique of combination of lipid molecules and discrete metal complexes makes it possible to design flexible, reversible, and signal-responsive supramolecular coordination systems. The concept of lipid packaging could also be expanded of other useful coordination compounds and should allow us to further develop the nanochemistry of coordination materials. Keywords: spin-crossover, mixed-valence, self-assembly

MS.B3.C.04 Stimuli-Responsive Multifunctional Metal-Organic Nanoparticles D. Ruiz-Molina,a F. Novio,a Cl. Rodríguez-Blanco,b J. Campo,b a Centro de Investigación en Nanociencia y Nanotecnología, Campus UAB, 08193 Bellaterra (Spain), bInstituto de Ciencia de Materiales de Aragón CSIC-Universidad de Zaragoza, 50009 Zaragoza (Spain). E-mail: [email protected] Coordination polymers are a class of solids created by the association of metal ions and multitopic organic ligands that are

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electronic devices based on the charge hopping or trapping. Recently, we have developed novel surface coordination chemistry for fabrication of supramolecular assemblies from redox-active dinuclear Ru complexes bearing tetrapod phosphonate anchors as a layer-bylayer building block[1]. Using zirconium(IV) ion as a chemical glue, the multilayer structure with a predetermined number of layers has been constructed. The characteristics of electronic conduction through the present supermolecular layered structures have been studied on the temperature dependence of current-voltage (I-V) characteristics. The I-V measurements were performed by changing the number of Ru complex layers, n (n = 1~6). Non-linear I-V characteristics were observed. The I-V plots with different number of layers are collected in Fig 1. As the number of layers, n, increases, two different regimes, a linear and an exponential ones, are observed, which indicates two different conduction mechanisms are involved; i.e., tunnelling and sequential hopping mechanisms. From this context, we have proposed a “stepping-stone mechanism” for the long-range electron transport of ruthenium multilayer films on the basis of the results of theoreticalexperimental collaboration[2].

Microsymposia excellent candidates for the fabrication of functional nanoscale metal–organic particles (NMOPs). Inspired by this approach, we have focussed on the structuration of well-known functional building blocks in the form of stimuli-responsive NMOPs.[1] Size-tunable valence tautomeric (VT) nanoparticles have been obtained by precipitation/coordination polymerization of electronically bistable [CoIII(semiquinone)(catecholate)] units with the appropriate ditopic bridging ligand. VT nanoparticles interconvert between two different electronic (or degenerate) states with different optical, magnetic and mechanical properties in response to different external stimuli such as heat or light irradiation. Moreover, the switching behaviour is observed around room temperature making them feasible for real applications as switchable materials, sensors or storage memories.[2] Special attention has also been paid to the role played by the ditopic bridging ligand or polymerizing agent. Whereas the flexible 1,4-Bis(imidazol-1-ylmethyl)benzene ligand yields amorphous nanoparticles, the 4,4’-bipyridine and related ligands yield a nanocrystalline material whose morphology and crystalline phase can be tuned upon a systematic variation of the experimental conditions This fact has been used to establish for the first time a systematic property/ crystalline phase/morphology correlation that can be of interest for the fabrication of several other different functional NMOPs.[3]

fragment [fac-Re(CO)3(bipy)]+ [1]. The systems have been fully characterized; in some cases we observed the formation of the charge separation state [2]. We have now modified the system to improve the CS step: a porphyrin antenna unit conjugated to the bipyridyl ligand [3] and a functionalized fullerene have been attached to the [Re(CO)3(dmso)3] [X] precursor [4] in order to obtain a triad (Figure). In a parallel study, a multicomponent self-assembled triad has been efficiently prepared by selective coordination of an aluminium(III) monopyridylporphyrin, a ruthenium(II) porphyrin and a carboxylate unit [5]. A summary of the synthesis, solution characterization and photophysical behavior of these novel porphyrin based systems will be presented.

[1] M. Casanova, E. Zangrando, E. Iengo, E. Alessio, M.T. Indelli, F. Scandola, M. Orlandi, Inorg. Chem., 2008, 47, 10407-10418. [2] T. Gatti, E. Iengo, P. Cavigli, E. Zangrando, E. Alessio, F. Scandola, M.T. Indelli, manuscript in preparation. [3] A. Grabrielsson, J.R. Lindsay Smith, R.N. Perutz, Dalton Trans., 2008, 4259-4269. [4] M. Casanova, E. Zangrando, F. Munini, E. Iengo, E. Alessio, Dalton Trans., 2006, 5033-5045. [5] E. Iengo, G. Dan Pantos, J.K.M. Sanders, M. Orlandi, C. Chiorboli, S. Fracasso, F. Scandola, Chem. Sci., 2011, 2, 676-685.

Keywords: porphyrin, charge-separation, coordination

MS.B3.C.06 [1] I. Imaz, J. Hernando, D. Ruiz-Molina, D. Maspoch, Angew. Chem. Int. Ed, 2009, 48, 2325 –2329. [2] I. Imaz, D. Maspoch, Cl. Rodríguez-Blanco, J. M. Pérez-Falcón, J. Campo, D. Ruiz-Molina, Angew. Chem. Int. Ed, 2008, 47, 1857 –1860. [3] F. Novio, Cl. Rodríguez-Blanco, J. Campo, D. Ruiz-Molina, J. Am. Chem. Soc. 2012, submitted.

Keywords: nanoparticles, multifunctional, stimuli-responsive

MS.B3.C.05 Porphyrin based Metal-Mediated Triads for Photoinduced Charge Separation Paolo Cavigli,a Elisabetta Iengo,a Tatiana da Ros,a Maria Teresa Indelli,b Franco Scandola,b aDepartment of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, (Italy). bDepartment of Chemistry, University of Ferrara, Ferrara, (Italy). E-mail: paolo. [email protected] The central processes in natural photosynthesis are light-driven electron transfer from the antenna-donor chromophore to the primary acceptor, and the subsequent charge separation (CS) to enable the reduction of substrates. The transfer of these design principles to artificial systems has led to the development of multicomponent metalmediated supramolecular systems. Recently we have developed a new series of porphyrin-rhenium(I) dyad systems, based on a zinc(II) monopyridylporphyrin, antenna and electron donor unit, directly coordinated to the electron acceptor

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Accurate Organization of Nanoparticles Based on Magnetic Coordination Compounds Alicia Forment-Aliaga,a Eugenio Coronado,a Elena PinillaCienfuegos,a Sergio Tatay,b Laure Catala,c José A. Plaza,d aICMol Univ. Valencia C/ Catedrático José Beltrán 2, E-46980, Paterna (Spain).b Unité Mixte de Physique CNRS/Thales. 1 Av. Augustin Fresnel, F-91120 (France). cInstitut de Chimie Moléculaire et des Matériaux d’Orsay, CNRS, Univ. Paris Sud 11, 91405 Orsay, (France). dIMBCNM (CSIC) Campus UAB-Bellaterra, E-08193, Barcelona (Spain). E-mail: [email protected] Magnetic molecules and nanoparticles (NPs) have recently shown great potential for applications in magnetic data storage and processing. A fundamental requirement for the exploitation of their functionalities at the nanoscale is the capability to deposit these objects on surfaces and moreover to do it in a controlled manner. Current interest is focused on procedures that combine top-down with bottom-up methods, like the combination of the local oxidation lithography (LON) with Atomic Force Microscopy (AFM) and the functionalization of substrates with Self Assembly Monolayers (SAMs). [1] At present, we are working with different coordination compounds NPs. In this presentation we focus on a family of bimetallic cyanidebridged coordination compounds known as Prussian blue analogues (PBA). PBA are molecule-based magnetic compounds of general formula AxMy[M’(CN6)]z (A = alkali-metal cation, M and M’ = transition metal ions) whose magnetism can be modified with an external perturbation.[2] The reduction of size at the nanoscale may result in the onset of new properties or in the improvement of the existing ones.[3]

Microsymposia The aim of this work is to control the deposition of superparamagnetic PBA-NPs on functionalized nanopatterned Si(100) surfaces. Recently, T. Mallah et al. have developed a procedure for the grafting of these NPs.[4] However, an easier and more accurate protocol leading to deposit PBA-NPs at the nanoscale would be desirable. In this scenario, we have taken advantage of the anionic nature of the PBA-NPs to develop a simple procedure for their nanopatterning. The method uses the electrostatic interactions established between the negatively charged nanoparticles of different sizes (from ~6 to ~25 nm) and a SAM of positively charged aminopropyltriethoxysilane selectively grown on SiO2 marks created through LON. The accuracy of the procedure permits the deposition of one single nanoparticle on a modified oxide dot. By using AFM, Magnetometry, IR Spectroscopy and Auger Electron Spectroscopy we show that the deposition process does not affect NPs properties. [5]

Keywords: Local Oxidation Nanolithography, Nanoparticles, Prussian Blue Analogues

MS.B3.C.07 Structuring metal-organic materials by Dip-pen Nanolithography Elena Bellido,a Pablo González-Monje,a A. Sanchez,b S. CardonaSerra,c E. Coronado,c F. Novio,a D. Ruiz-Molina,a aCentre d’Investigació en Nanociència i Nanotecnologia CIN2, CSIC-ICN (Spain). bCentro de Electroquimica y Energía Química (CELEQ), Universidad de Costa Rica (Costa Rica).cInstituto de Ciencia Molecular ICMOL, Universitat de Valencia, Valencia (Spain). E-mail: [email protected] Dip-Pen Nanolithography (DPN) is a direct-write scanning probe lithography technique in which an Atomic Force Microscopy (AFM) tip is used to directly deliver chemical reagents onto a target substrate through the meniscus formed at the point-of-contact between the tip and the surface. Due to its nanoscale positioning and imaging abilities, this technique is uniquely able to dispense localized nanostructures with control over the absolute placement at fixed surface coordinates. In this communication the potential of this technique for the structuration of metal-organic materials into advanced architectures on surfaces is presented. AFM tips have been used to dispense less than femtoliter droplets of precursor solutions containing both the organic bridging ligands and metal ions building blocks on a target area of a surface. Thus each droplet can act as a reactor vessel to confine the coordination polymerization process at the nanoscale while controlling the incubation conditions to yield the desired structure. Representative examples of the in situ growth of nanoscale metal-organic frameworks (MOFs), including electrically switchable cobalt complexes, and hollow capsules of polyoxometalates (POMs) will be presented (see Figure 1).[1,2] These results open new avenues for all the possible applications that can be derived from the implications of metal-organic materials on surfaces, such as catalysis, information technologies or biomedical applications.

Figure 1. (a) Schematic illustration of the deposition method. (b, c) FE-SEM images of arrays of metal-organic structures growth inside the confined solution droplets deposited by an AFM tip. [1] E. Bellido, S. Cardona-Serra, E. Coronado, D. Ruiz-Molina, Chem. Commun. 2011, 47, 5175-5177. [2] E. Bellido, A. Sánchez, F. Novio, P. González-Monje, D. Ruiz-Molina (In preparation).

Keywords: dip-pen nanolithography, metal-organic frameworks, polyoxometalates

MS.B3.C.08 New stable, closed-shell, Copper(III) porphyrin fullerene dyads Magal Saphier1,2, Israel Zilbermann1,3, Tova Yifrah 3, Oshra Saphier 2 , Axel Kahnt4 and Dirk M. Guldi,4 1Nuclear.Research.Centre.Negev, Beer-Sheva, Israel, 2Sami Shamoon College of Engineering of the Negev –Israel, 3Ben Gurion University of the Negev, Beer-Sheva –Israel, 4 Friedrich-Alexander-Universitat Erlangen-Nuernberg -Germany. E-mail: [email protected] Fllowing the characterization of Copper(III) tetraphenylporphyrin1, we herein report the characterization of novel closed-shell, diamagnetic, Copper(III) porphyrin fullerene dyads. Photoinduced electron-transfer processes have been detected in a new fullerene-based Copper(III) tetraphenylporphyrin (TPP) dyad, Nanosecond experiments show photo induced charge separation over more than 1000ns.

[1] The Redox Chemistry of Copper tetraphenylporphyrin revisited, JPP, 2012 submitted.

Keywords: Copper(III) porphyrin, charge separation, porphyrin fullerene dyads

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[1] R.V. Martínez, J. Martínez, M. Chiesa, R. García, E. Coronado, E. PinillaCienfuegos, S. Tatay. Adv. Mater. 2009, 22(5), 588-591. [2] S. Ferlay, T. Mallah, R. Ouahes, P. Veillet, M. Verdaguer. Nature, 1995, 378, 701–703. [3] L. Catala, A. Gloter, O. Stephan, G. Rogez, T. Mallah. Chem.Commun. 2006, 1018–1020. [4] (a) B. Fleury, F. Volatron, L. Catala, D. Brinzei, E. Rivière, V. Huc, C. David, F. Miserque, G. Rogez, L. Baraton, S. Palacin, T. Mallah. Inorg. Chem. 2008, 47, 1898-1900; (b) A. Ghirri, A. Candini, M. Evangelisti, G. C. Gazzadi, F. Volatron, B. Fleury, L. Catala, C. David, T. Mallah, M. Affronte Small 2008, 4, 2240–2246. [5] E. Coronado, A. Forment-Aliaga, E. Pinilla-Cienfuegos, S. Tatay, L. Catala, J. A. Plaza Adv. Func. Mater. accepted.

Microsymposia MS.B3.C.09 Functional Carbon-Rich Organometallic Compounds: Theoretical Aspects Karine Costuas, Sciences chimiques de Rennes, UMR 6226 CNRS – Université de Rennes 1, Avenue du Général Leclerc F-35042 Rennes (France). E-mail: [email protected] Molecular materials based on the assemblage of organometallic fragments and conjugated organic ligands are among the most studied compounds in coordination chemistry. This is due to their relatively good stability combined with their excited-state and redox properties which confer them interesting physical properties in several domains (magnetism, optics, electrochemistry…). These multifunctional systems are promising candidates to be incorporated in nanoscale devices for molecular electronics and/or spintronics. The control and manipulation of the interactions between the metal termini of such systems are of great practical importance, but present considerable conceptual challenges. These challenges can be met by combining experimental and theoretical studies. Using results obtained from theoretical calculations of density-functional theory (DFT) type, some physical properties of representative compounds can be explained and predicted. Particular emphasis will be put on the electronic reasons of the changes in structural and physical properties upon oxidation or reduction, or upon structure modification of metallic moieties and of the conjugated ligands. Two series of compounds will be more particularly detailed: (1) The case of di-iron-(bis)acetylide-pyridine species which shows an unprecedented example of bistability of its mixed-valent forms;[1] (2) The multifunctional behavior of Ru(II) acetylide compounds containing a bistable photochromic unit (DTE) for which conductivity studies were performed (experimentally and theorecitally).[2] [1] C. Lagrost, K. Costuas, N. Tchouar, H. Le Bozec, S. Rigaut, Chem. Commun., 2008, 6117-19. [2] K. Costuas, O. Cador, F. Justaud, S. Le Stang, F. Paul, A. Monari, S. Evangelisti, L. Toupet, C. Lapinte, J.-F. Halet, Inorg. Chem., 2011, 50, 12601-22.

Keywords: Multifunctional materials, DFT calculations, bistability

MS.B3.C.10 Tentative RVB Electronic States in CuNCN Andrei L. Tchougréeff,a,b,c Richard Dronskowski,a aInstitute of Inorganic Chemistry, RWTH Aachen University, D-52056 Aachen, (Germany); b Poncelet Laboratory, Independent University of Moscow, Moscow (Russia); cDepartment of Chemistry, Moscow State (Lomonosov) University, Moscow (Russia). E-mail: [email protected] CuNCN is a very special member of a novel class of materials, the transition-metal carbodiimides M(NCN) which may be looked upon as nitrogen-based analogs of the corresponding oxides with the rock-salt structure [1]. Although CuNCN is quite similar to the other family members in terms of stoichiometry and crystal structure, it strikingly differs from them with respect to its magnetic behavior. Indeed, while all other known transition-metal carbodiimides manifest more or less standard antiferromagnetic ground states, the nonmetallic CuNCN exhibits no magnetic scattering of polarized neutrons at either temperature down to several Kelvin [1,2]. At intermediate temperatures (between 80 and 350 K which, in fact, defines the upper limit of chemical stability of the material) CuNCN shows temperatureindependent paramagnetism, which changes to a fair Arrhenius decay below 80 K [3] but without any signs of magnetic ordering as

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found from various spectroscopic techniques (ESR, NMR, mSR). We have conjectured [3,4] that the above features may be related to the formation of resonating valence bond (RVB) – spin-liquid – phases of unpaired electrons residing on Cu2+ ions on an anisotropic triangular lattice. More specifically, the Arrhenius decay is tentatively attributed to the transition from a medium-temperature non-gapped 1D-RVB state to the low-temperature 2D-RVB gapped state. Following this idea, we have suggested [5] tentative structural manifestations of the aforementioned 1D- to 2D-RVB transition. A recent synchrotron structural study [6] is in harmony with the theoretical predictions [5]. This work is supported by DFG and by RFBR through the grant no. 10-03-00155. [1] X. Liu, R. Dronskowski, R. K. Kremer, M. Ahrens, C. Lee, M.-H. Whangbo, J. Phys. Chem. C 2008, 112, 11013. [2] H. Xiang, X. Liu, R. Dronskowski, J. Phys. Chem. C 2009, 113, 18891. [3] A. Zorko, P. Jeglič, A. Potočnik, D. Arčon, A. Balčytis, Z. Jagličić, X. Liu, A. L. Tchougréeff, R. Dronskowski, Phys. Rev. Lett. 2011, 107, 047208. [4] A. L. Tchougréeff, R. Dronskowski, arXiv:1008.0182. [5] A. L. Tchougréeff, R. Dronskowski, arXiv:1111.7210. [6] A. L. Tchougréeff, X. Liu, P. Müller, W. van Beek, U. Ruschewitz, R. Dronskowski, in preparation.

Keywords: Copper carbodiimide, RVB states

MS.B3.C.11 Extremely Strong Self-Assembly of a Bimetallic Salen Complex Visualized at the Single-Molecule Level Giovanni Salassa,a Michiel J.J. Coenen,b Sander J. Wezenberg,a Bas L.M. Hendriksen,b Sylvia Speller,b Johannes A.A.W. Elemans,*,b Arjan W. Kleij,*a,c aInstitute of Chemical Research of Catalonia (ICIQ), Tarragona (Spain). bInstitute for Molecules and Materials, Radboud University Nijmegen, Nijmegen (The Netherlands). cCatalan Institute for Research and Advanced Studies (ICREA), Barcelona (Spain). E-mail: [email protected] Salphen ligands (salphen = N,N´-bis-salicylideneimine-1,2diaminobenzene) are rigid and planar in nature and impose an unusual square planar geometry around a Zn(II) ion. As a result, the axial coordination sites in these structures strongly bind suitable Nor O-donor ligands, or may result in self-assembled structures.[1] In particular, self-assembled molecules that provide 1D nano-structures can be an important tool for developing new nano-materials. Herein, we report on studies centered on a bis-Zn(salphen) structure that shows extremely strong self-assembly both in solution as well as at the solid−liquid interface as evidenced by scanning tunnelling microscopy (STM), competitive UV−vis and fluorescence titrations, dynamic light scattering (DLS), and transmission electron microscopy. [2] Density functional theory analysis on the bis-Zn(salphen) complex rationalizes the very high stability of the self-assembled structures provoked by unusual oligomeric (Zn−O)n coordination motifs within the assembly. This coordination mode is strikingly different when compared with mononuclear Zn(salphen) analogues that form dimeric structures having a typical Zn2O2 central unit.[3] The high stability of the multinuclear structure therefore holds great promise for the development of stable self-assembled monolayers with potential for new opto-electronic materials.

Microsymposia [1] Coates, C. G.; Jacquet, L.; McGarvey, J. J.; Bell, S. E. J.; Al-Obaidi, A. H. R.; Kelly, J. M. J. Am. Chem. Soc. 1997, 119, 7130 – 7136. [2] Fraser, M.G.; Blackman, A.G.; Irwin, G.I.S.; Campbell, P.E.; Gordon, K.C. Inorg. Chem. 2010, 49, 5180 – 5189. [3] Kestemont, G.; Halleux, V. d.; Lehmann, M.; Ivanov, D. A.; Watson, M.; Geerts, Y. H. Chem. Commun. 2001, 2074-2075. [4] Fraser, M.G.; Clark, C.A.; Horvath, R.; Lind, S. J.; Blackman, A. G.; Sun, X.-Z.; George, M.W.; Gordon, K.C. Inorg. Chem. 2011, 50, 6093-6106.

Keywords: charge-transfer, dppz, HATN

MS.B3.C.13

Keywords: Salen Ligand, Self-assembly, Supramolecular polymers

MS.B3.C.12 Electronic Properties of Re(I) Complexes with Sulfur-Containing Polypyridyl Ligands Michael Fraser,a Raphael Horvath,a Holly van der Salm,a Nigel Lucas,a Keith C Gordon,a aMacDiarmid Institute for Advanced Materials and Nanotechnology, Department of Chemistry, University of Otago, Dunedin New Zealand. E-mail: [email protected] Metal complexes based on dipyridophenazine (dppz) ligands are of considerable interest due to their rich photophysical properties, which are due to the presence of two unoccupied molecular orbitals with their electron density found of different sections of the ligand.[1] The LUMO is generally found on the phenazine portion, the LUMO+1 found over the phenanthroline. This work presents our findings on rhenium dipyridophenazine complexes appended with electron-rich sulfur-based substituents at the 11,12-position.[2] These have been shown to exhibit unique photophysical effects where a metal-ligand charge-transfer and an intraligand charge transfer occur, donating electron density to the phenazine based orbital. The effects of appending similar electron-rich moieties to a similar ligand, hexaazatrinapthalene are also discussed. Hexaazatrinapthalene (HATN) is a tris-bidentate ligand able to bind up to three metal ions. HATN-based ligands appended with long alkyl chains have been shown to form discotic liquid crystals, with the ability to effectively carry charge.[3] We have previously demonstrated the ability to synthesize mono-, bi- and tri-nuclear {Re(CO)3Cl} complexes of a simple HATN ligand, and characterized their photophysical properties.[4] Presented here are the electronic properties a series of rhenium complexes of HATN ligands with electron-donating thioether groups.

From hybrid multifunctional multilayers towards monolayer systems Efrén Navarro-Moratalla,a Elena Pinilla-Cienfuegos,a Carlos MartíGastaldo,a, b Eugenio Coronado.a aInstituto de Ciencia Molecular (ICMol), Universidad de Valencia, Valencia, (Spain). bDepartment of Chemistry, University of Liverpool, Liverpool (UK). E-mail: efren. [email protected] Owing to the manifold of attractive properties that are intrinsic to molecules (lightness, biocompatibility and easy processability for instance), molecule-based materials are nowadays a key area within materials science. Molecular building blocks allow for the blend of their inherent properties with electronic ones, that are classically attributed to solid-state materials (electrical conductivity, non-linear optics, ferroelectricity, ferromagnetism, etc.).[1] Furthermore they provide a wide range of functionalities that may be combined at will. This sets the basis of the hybrid approach, in which two or more different molecular building blocks are combined in the same material. Unprecedented multifunctionality has consequently arisen.[2] A more recent alternative for the synthesis of multifunctional materials takes advantage of the combination of molecule-based components with solid-state inorganic structures. This new strategy paves the way for obtaining hybrid systems that combine the robustness of an inorganic host with the versatility of molecular building blocks. The principles of this approach are based on the chemical combination of two distinct electrostatic counterparts, each carrying its intrinsic property into the final single-phase hybrid material. It is a selfassembly technique that provides an entirely new route for combining functionalities in a highly controllable way. So far, the method has opened the door for the combination of what are considered to be two antagonistic states of matter: ferromagnetism and superconductivity. [3] Moreover it has also proved as a useful approach for the insertion of single-molecule magnets in between superconducting [TaS2] layers. [4] This technique relies on the facile exfoliation of the layered inorganic solid-state counterpart, which is built from the stacking of neutral weakly-interacting 2D layers. One may therefore easily envision the isolation of individual crystalline sheets of the inorganic host. Either mechanically or via wet chemistry methods, single layers may be conveniently deposited on a wide variety of surfaces. It is the starting point of an all-new strategy for the synthesis of multifunctional multilayers and for their application in potentially sensing devices. [1] Miller JS. Adv. Mater. 1990, 2, 98-99. [2] For instance: Bénard S, Yu P, Audiére JP, Riviére E, Clément R, Ghilhem J, Tchertanov L, Nakatani KJ. J. Am. Chem. Soc. 2000, 122, 9444–9454. [3] Coronado, E., Martí-Gastaldo, C., Navarro-Moratalla, E., Ribera, A., Blundell, S., Baker, P. Nature Chem 2010, 2, 1031–1036. [4] Coronado, E., Martí-Gastaldo, C., Navarro-Moratalla, E., Burzurí, E., Camón, A., Luis, F. Adv. Mater. 2011, 23, 5021–5026.

Fig 1. Example of Re(I) dppz (left) and HATN (right) complexes presented.

Keywords: hybrid superconductors

multifunctional

materials,

layered

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[1] G. Salassa, A. M. Castilla, A. W. Kleij, Dalton Trans., 2011, 40, 52365243. [2] G. Salassa, M. J. J. Coenen, S. J. Wezenberg, B. L. M. Hendriksen, S. Speller, J. A. A. W. Elemans, A. W. Kleij, J. Am. Chem. Soc., DOI: 10.1021/ ja3030802. [3] M. Martínez Belmonte, S. J. Wezenberg, R. M. Haak, D. Anselmo, E. C. Escudero-Adań, J. Benet-Buchholz, A. W. Kleij, Dalton Trans., 2010, 39, 4541-4550.

Microsymposia MS.B3.C.14 Synthesis and STM studies of a new family of nanovehicles and alternative wheels Romain Garbage,a Henri-Pierre Jacquot de Rouville,a Rita Cook,a Adeline Pujol,a Agnès Sirven,a Gwénaël Rapenne,a,b aNanoSciences Group, CEMES-CNRS, Toulouse (France). bUniversité de Toulouse, UPS, Toulouse (France). E-mail: [email protected] Technomimetic molecules[1] are molecules designed to imitate macroscopic objects at the molecular level, also transposing the motions that these objects are able to undergo. Particularly interested in controlling the rotation at the nanoscale and following a bottom-up approach, we synthesized an aromatic axle functionalized with two triptycenyl nanowheels 1. For the first time the rotation of a wheel on a copper surface has been demonstrated, induced by the tip of a Scanning Tunneling Microscope.[2] Two nanovehicules equipped with these wheels have been synthesized[3] and STM experiments are currently underway on alternative semiconductor surfaces to be able to work at room temperature. In order to build more efficient nanovehicles, we also synthesized[4] a new family of bowl-shaped nanowheels based on subphtalocyanine 2. The bowl shape allows to decrease the interaction between the aromatic system and the surface. Furthermore, a labelling nitrogen atom has been introduced in the nanowheel to directly monitor the rotation movement by contrast changes in the STM image. As an example of a target, nanovehicule 3 is our ultimate target including these new wheels.

for device optimization. A key breakthrough is then to realize “synchronic bistability”, in which the physical properties derived both from an individual molecule and from an assembly of molecules can be simultaneously interconverted with an inseparable correlation. This paper will show our recent developments in synchronizing molecular and macroscopic transformations by electron transfer processes induced by heat, light, and electrochemical redox reactions.[1]

[1] H.-C. Chang, K. Komasaka, K. Kishida, T. Shiozaki, T. Ohmori, T. Matsumoto, A. Kobayashi, M. Kato, S. Kitagawa, Inorg. Chem., 2011, 50, 4279-4288. [2] D. Kiriya, K. Nakamura, S. Kitagawa, H.-C. Chang, Chem. Commun., 2010, 46, 3729-3731. [3] D. Kiriya, K. Nakamura, H.-C. Chang and S. Kitagawa, Chem. Commun. 2009, 4085-4087. [4] D. Kiriya, H.-C. Chang, K. Nakamura, D. Tanaka, K. Yoneda, S. Kitagawa, Chem. Mat. 2009, 21, 19801988. [5] D. Kiriya, H.-C. Chang, S. Kitagawa, J. Am. Chem. Soc. 2008, 130, 5515-5522. [6] H.-C. Chang, T. Shiozaki, A. Kamata, K. Kishida, T. Ohmori, D. Kiriya, T. Yamauchi, H. Furukawa, S. Kitagawa, J. Mat. Chem. 2007, 17, 4136-4138 (Front Cover).

Keywords: bistability, electron transfer, non-innocent ligand

MS.B3.C.16 [1] G. Rapenne, Org. Biomol. Chem., 2005, 3, 1165-1169. [2] L. Grill, F. Moresco, G. Rapenne, S. Stojkovic, X. Bouju, C. Joachim, Nature Nanotech., 2007, 2, 95-98. [3] H.P. Jacquot de Rouville, R. Garbage, R.E. Cook, A.R. Pujol, A.M. Sirven, G. Rapenne, Chem. Eur. J., 2012, 18, 3023-3031. [4] H.P. Jacquot de Rouville, R. Garbage, F. Ample, A. Nickel, J. Meyer, F. Moresco, C. Joachim, G. Rapenne, submitted.

Keywords: triptycene, subphtalocyanine, STM

MS.B3.C.15 Molecular and Macroscopic Transformation of Assembled Metal Complexes by Electron Transfers Ho-Chol Chang,a aDepartment of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, Hokkaido (Japan). E-mail: [email protected] The use of bistable molecules as switches, sensors, recording material and actuators holds promise for future molecule-based electronics, leading to well-defined bistable molecules that have to date demonstrated photochromism, spin crossover, electrochromism, and so on. Although advances in strategies for synthesizing bistable molecules have enabled control of behaviors and cooperativity in solid phases, the requirement that macroscopic phases are synchronously controlled, to utilized not only the molecular properties of an individual molecule but also integrated properties of molecular assemblies with different shape, physical properties and essential perfect cooperativity

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Supramolecular assembly of 1D metal-organic structures Rubén Mas-Ballesté, Mohammad-Reza Azani, Felix Zamora, Departamento de Química Inorgánica, Universidad Autónoma de Madrid, 28049 Madrid (Spain). E-mail: [email protected] A main challenge in nanotechnology is to build functional organized systems based on molecules in order to reach the maximum level of miniaturization. 1D structures with metal atoms in close contact are specially appealing for their potential use as molecular wires. This communication presents from various perspectives the generation of supramolecular 1D metal-organic structures. Initially, obtention of 1D structures based on metal-metal interactions has been explored. Specifically, the factors that affect interactions Pt2+···Pt2+ and Au+···Au+ have been analyzed in depth. On one hand, assembly [AuL2] (L= dithiocarboxylate) results on formation of species [AuL2]n (n=1-3) in solution and oligomeric/polymeric structures in crystalline samples. Such phenomenon is due to the combination of several interactions including aurophilia. On the other hand, d8-d8 weak interactions account for reversible assembly in solution of [PtL4]n (L= dithiocarboxylate). The factors that modulate such assemblies have been investigated. Finally, in a different basis, the reversible process of assembly-disassembly of conductor coordination polymers, based on metal-ligand interactions has been studied. In particular, the electrical conductor MMX polymers [PtIL4]n (L= dithiocarboxylate) disassemble in solution into equimolar amounts of [PtL4] and [PtI2L4]. Interestingly, crystallization allows to regenerate the polymeric structure preserving electric conductivity. Such behavior facilitated

Microsymposia

[1] Ruben Mas-Ballesté, Rodrigo Gonzalez-Prieto, Alejandro Guijarro, Miguel A. Fernandez-Vindel, Felix Zamora, Dalton Trans., 2009, 7341-7343. [2] Maria Luz Gallego, Alejandro Guijarro,Oscar Castillo, Teodor Parella, Rubén MasBallesté, Félix Zamora, Cryst. Eng. Comm. 2010, 12, 2332–2334. [3] Denis Gentili, Gonzalo Givaja, Rubén Mas-Ballesté, Mohamad-Reza Azani, Arian Shehu, Eva Mateo-Martí, Pierpaolo Greco, Félix Zamora and Massimiliano Cavallini, Chem. Sci., 2012 accepted, DOI: 10.1039/C2SC00029F. [4] Rubén Mas-Ballesté, Julio Gómez-Herrero and Félix Zamora, Chem. Soc. Rev., 2010, 39, 4220–4233.

[1] J.-M. Lehn, Supramolecular Chemistry; Wiley-VCH: New-York 1995. [2] a) G. K. Such , A. P. R. Johnston, F. Caruso Chem. Soc. Rev., 2011, 40, 19-29; b) T. Kato, Science 2002, 295, 2414, 2418. [3] T. Kato, N. Mizoshita, K. Kishimoto, Angew. Chem. Int. Ed. 2006, 45, 38-68. [4] a) R. Perochon, P. Davidson, S. Rouzière, F. Camerel, L. Piekara-Sady, T. Guizouarn, M. Fourmigué, J. Mater. Chem., 2011, 21, 1416-1422; b) S. Debnath, J.-F. Bergamini, F. Artzner, C. Mériadec, F. Camerel, M. Fourmigué, Chem. Commun., 2012, 48, 2283-2285; c) S. Debnath, H. F. Srour, B. Donnio, Marc Fourmigué, F. Camerel, RSC Adv., 2012, DOI: 10.1039/C2RA20332D.

Keywords: Metal-bis(dithiolene), Gels, Liquid crystals

Keywords: Molecular Wires, Supramolecular Assemblies, Weak Metal-Metal Interactions, Coordination Polymers

MS.B3.C.17 Active and soft nanostructures containing metal-bis(dithiolene) Complexes Franck Camerel, Bertrand Donnio, Sisir Debnath, Marc Fourmigué, Sciences Chimiques de Rennes, Université Rennes 1, UMR CNRS 6226, Campus de Beaulieu, 35042 Rennes, France. E-mail: fcamerel@ univ-rennes1.fr Supramolecular chemistry,[1] in which non-covalent interactions drive the formation of elaborated and exotic superstructures, is an elegant way to organize small molecules into highly functional architectures of potential interest in life and material sciences.[2] Among the diversity of materials able to self-assemble into organized superstructures at the micro and macroscopic scale, liquid crystalline and gel-like materials continuously emerge as attractive candidates to form active architectures, especially in the fields of optics and electronics.[3] We present here the design and the successful synthesis of new functional metal-bis(dithiolene) complexes able to self-assemble in solid state or in solution into highly organized supramolecular architectures. Self-assembly into soft materials allow the emergence of original optical and magnetic properties which can be modulated by external stimuli.[4] a) Chemical structure of a liquid crystalline gold-bisdithiolene complex; b) Texture of the hexagonal columnar phase of the gold complex at 100 °C observed between crossed-polarizers (symbolized by the cross in the corner of the picture); c) Chemical structure of a cholesteryl based metallogelator containing a nickel-bis(dithiolene) core; d) AFM tapping mode image (0.25 mm × 0.25 µm) of a dried diluted gel of the metallogelator in cyclohexane (C = 0.2 mg.L-1) showing extended fibers with an average diameter of ~12 nm.

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the use of “wet lithographic” methods for the design sub-micrometric electronic devices.

9 - 13 September 2012

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MS.C1.KN2

Products for the Formation of Monomers from Waste Natural Oils David J. Cole-Hamilton,a Marc R. L. Furst,a Ronan Le Goff,a James Mgaya,a,b Egid Mubofu,b Jennifer Julis,a aSchool of Chemistry, University of St. Andrews, St. Andrews, Fife, KY16 9ST. Chemistry Department, bUniversity of Dar es Salaam, P.O.Box 35061, Dar es Salaam, Tanzania. E-mail: [email protected]

On the Catalytic Properties of Ionic Liquid Soluble Metal Nanoparticles Jairton Dupont. Institute of Chemistry, UFRGS, Porto Alegre, RS, Brazil. E-mail: [email protected]

Walk into any room in your house and look around you. The carpets, clothes, paint, polishes, plastics, shampoo, perfume, lino, medicines, cleaning fluids – almost everything has been made by the Chemical Industry. We all need and use products from the chemical industry every hour of every day and yet their production is threatened, since almost all of them come from petrochemical resources. As the supply of crude oil comes towards its end the prices will rise and eventually the very many useful products will not be available. Replacing oil as a feedstock for Chemical production is a huge challenge, which will lead to a complete reinvention of the petrochemical industry into a Chemical industry based on renewable resources. We shall describe work in which the C1 compounds, CO and methanol are used to convert unrefined natural oils, including Tall Oil a chemical available at 2 M tonnes per year into a,w-diesters of different chain lengths directly or after double bond metathesis.[1, 2] The hydrogenation of the product diesters to diols or nylons will also be described,[1] as will the condensation polymerisation of the diesters and diols to form important polyesters for fibres and packaging directly from natural resources.[3, 4] Finally we shall describe the synthesis of a range of single monomers from the carbonylation of cardanol, a major component of waste cashew nut shell liquid, available at 300,000 tonnes per year[5] either directly or after metathesis.

Fig. 1 Polyesters from C1 modification of natural oils [1] M. R. L. Furst, R. le Goff, D. Quinzler, S. Mecking, D. J. Cole-Hamilton, Green Chem., 2011, 14, 472-477. [2] C. Jimenez-Rodriguez, G. R. Eastham, D. J. Cole-Hamilton, Inorg. Chem. Commun., 2005, 8, 878-881. [3] D. Quinzler, S. Mecking, Angew. Chem. Int. Ed., 2010, 49, 4306-4308. [4] F. Stempfle, D. Quinzler, I. Heckler, S. Mecking, Macromolecules, 2011, 44, 4159-4166. [5] S. H. Azam-Ali, E. C. Judge, Small scale cashew nut processing Food and Agriculture Organisation, Rome, 2004.

Keywords: Methoxycarbonylation, natural oils, polyesters

Ionic liquids (ILs)[1] provide a flexible liquid platform for catalysis by transition metal nanoparticles. Indeed, ILs can act as the “solvent”, stabilizer, ligand and support for MNPs. It is possible to design metal nanoparticle catalysts for specific applications, in particular for the hydrogenation of arenes under very mild reaction conditions. Indeed, it appears that soluble MNPs in ILs behave as “single-site metal catalysts” for the hydrogenation of alkenes, but as “soluble-like” heterogeneous catalysts for the reduction of arenes or in Fischer-Tropsh synthesis. These MNPs may serve as simple reservoirs of soluble monometallic catalysts for C-C coupling reactions, such as the Heck and Suzuki reactions. ILs can be used as immobilizing agents, and a simple thin film of the fluid is necessary to give the desired properties for the catalytic device (stability, selectivity, etc.), thus significantly reducing the mass-transfer problems usually associated with reactions performed when ILs are used as solvents. [2] [1] J. Dupont, Acc. Chem. Res. 2011, 44, 1223-1231. [2] J. D. Scholten, B. C. Leal, J. Dupont, ACS Catal. 2012, 2, 184-200.

MS.C1.I1 Computational/experimental studies of molecular catalysts for reactions of CO2 with arenes Markus Hölscher,a Andreas Uhe,a Thomas Ostapowicz,a Walter Leitner,a Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Aachen, (Germany). E-mail: hoelscher@itmc. rwth-aachen.de Carbon dioxide (CO2) is a cheap, non toxic, highly abundant and renewable compound, which makes it an interesting C1 building block for chemical synthesis.[1] With regard to sustainable novel synthetic routes for intermediate and fine chemicals the atom economic production of aromatic and aliphatic acids would be highly attractive. In this context we have recently started to investigate two carboxylation reactions: a) the direct insertion of CO2 into C-H bonds of arenes to form aromatic carboxylic acids and b) the carboxylation of alkane C-H bonds or the hydrocarboxylation of alkene C-H bonds to arrive at aliphatic acids. Here we report on the latest computational and experimental results with a focus on the carboxylation of arenes. The introduction of CO2 into organic molecules usually is hampered by the high stability of the CO2 molecule just as is the functionalization of C-H bonds of arenes and alkenes which also are very stable. Accordingly, catalytic procedures are inevitable. Molecular catalysts for the direct transformation of CO2 are known though scarce.[2] Furthermore, more insight about the factors which govern carbon carbon bond forming events in reactions with CO2 is necessary. We therefore undertook a density functional theory (DFT) based computational investigation of promising catalyst lead structures, to elucidate if fundamental key steps of potentially active catalytic cycles can be carried out with activation barriers low enough for practical application. This concept then was extended to a complete screening of catalytic cycles to investigate if closed catalytic cycles can be calculated and furthermore to predict the expectable energetic spans and turn over frequencies (TOF) of plausible reaction mechanisms.[3] DFT calculations in recent years have developed into a standard tool for the direct support of experimental homogeneous catalysis as both the structures and energies of organometallic compounds can be

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Microsymposia predicted with satisfying accuracy. Accordingly, DFT calculations can now be incorporated into the catalyst design process at an earlier stage thus helping to plan experimental studies better prior to experimental art, and we have been following this approach for the development of carboxylation catalysts of the late transition metals. The studies presented here focus on pincer complexes of ruthenium and rhodium. Ruthenium pincer complexes have already proven to be active catalysts for H/D exchange reactions in a variety of arenes and –particularly important- ruthenium centres have been shown to active CO2 in many cases. We present a variety of complete catalytic cycles with an estimation of the TOF and initial results of experimental work directed at catalytic CO2 conversion for the production of aromatic acids. [1] a) T. Sakakura, J.-C. Choi, H. Yasuda, H. Chem. Rev. 2007, 107, 23652387; b) M. Aresta, A. Dibenedetto, Dalton Trans. 2007, 2975-2992; c) M. Peters, B. Köhler, W. Kuckshinrichs, W. Leitner, P. Markewitz, T. E. Müller, ChemSusChem 2011, 4, 1216-1240. [2] a) I. I. F. Boogaerts, S. P. Nolan, J. Am. Chem. Soc. 2010, 132, 8858-8859; b) I. I. F. Boogaerts, G. C. Fortman, M. R. L. Furst, C. S. J. Cazin, S. P. Nolan, Angew.Chem., Int. Ed. 2010, 46, 8674–8677; c) L. Zhang, J. Cheng, T. Ohishi, Z. Hou, Angew. Chem., Int. Ed. 2010, 46, 8670-8673; d) H. Mizuno, J. Takaya, N. Iwasawa, J. Am. Chem. Soc. 2011, 133, 1251-1253. [3] a) T. G. Ostapowicz, M. Hölscher, W. Leitner, Chem. Eur. J. 2011, 17, 10329-10338; b) A. Uhe, M. Hölscher, W. Leitner, Chem. Eur. J. 2012, 18, 170–177.

Keywords: catalysis, CO2 chemistry, DFT calculations

MS.C1.I2 Highly active magnesium catalysts for polycarbonates from CO2 and epoxides Charlotte K. Williams,a Michael R. Kember,a aDepartment of Chemistry, Imperial College London, London (UK). E-mail: m.kember07@ imperial.ac.uk The use of carbon dioxide as a renewable source of chemicals and fuels is very attractive as it is non-toxic, cheap and the waste product of many industries. The thermodynamic stability of CO2 makes its activation and transformation into useful chemicals challenging; low-energy activation of CO2 at ambient pressure (1 bar) is yet more difficult. Energy efficient, low-pressure catalytic transformations of CO2 are very rare and potentially very valuable. The low pressure copolymerisation of epoxides and CO2, which produces aliphatic polycarbonates, is a notable reaction.[1] Aliphatic polycarbonates have properties suitable for uses such as adhesives, packaging, elastomers and rigid plastics. Low molecular weight polycarbonate polyols are also precursors for the synthesis of polyurethanes, enabling transformation of CO2 into insulation foams. We have reported a series of di-zinc[2] and di-cobalt[3] catalysts based upon a macrocyclic pro-ligand, which showed excellent activity for the copolymerization of cyclohexene oxide (CHO) and CO2. These catalysts were particularly notable for their activity under low CO2 pressures (1 bar), producing poly(cyclohexene carbonate) (PCHC) with >99 % CO2 incorporation and high selectivity for PCHC (vs. cyclic carbonate). We have been particularly interested to explore the reactivity of different metals for this catalysis, as few metals are known to produce active catalysts. Most recent active catalysts use expensive, toxic cobalt; we were keen to explore cheaper, more biocompatible metals. We herein report the first highly active catalysts for this copolymerization based upon magnesium (see Fig. 1), which is biocompatible and inexpensive. The catalysts are analogous to our previously reported dizinc complexes, but show activity up to six times greater than zinc. The catalysts give greater selectivity for polymer (>99 %) than zinc, even at just 1 bar CO2 pressure and are highly tolerant of water; in fact

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water can be used instead of organic alcohols or acids as a renewable chain-transfer agent in the production of low-weight PCHC polyols for polyurethane synthesis.

[1] Kember, M. R.; Buchard, A.; Williams, C. K. Chem. Commun. 2011, 47, 141-163. [2] Kember, M. R.; Knight, P. D.; Reung, P. T. R.; Williams, C. K. Angew. Chem., Int. Ed. 2009, 48, 931-933; Jutz, F.; Buchard, A.; Kember, M. R.; Fredriksen, S. B.; Williams, C. K. J. Am. Chem. Soc. 2011, 133, 1739517405. [3] Kember, M. R.; Jutz, F.; Buchard, A.; White, A. J. P.; Williams, C. K. Chem. Sci. 2012, 3, 1245-1255; Kember, M. R.; White, A. J. P.; Williams, C. K. Macromolecules 2010, 43, 2291-2298.

Keywords: CO2, polymers, catalysis

MS.C1.I3 Olefin metathesis for the catalytic transformation of renewable resources Fischmeister Cédric, Raluca Malacea, Xiaowei Miao, Virginie Le Ravalec, Antoine Dupé, Pierre Dixneuf, Christian Bruneau, aInstitut des Sciences Chimiques de Rennes, University of Rennes 1, Rennes, (France). E-mail: [email protected] Olefin metathesis is a very powerful tool in organic and polymer synthesis that has shown a high potential for the transformation of renewable fats and oils.[1] In particular, cross-metathesis of fatty ester derivatives with functional olefins provides a direct access to compounds of interest as polymers precursors. The ruthenium catalyzed cross-metathesis of unsaturated renewable materials (Fatty Acid Methyl Esters) with various functional olefins and the direct synthesis of amino-esters by a tandem cross-metathesis/hydrogenation reaction will be presented (Scheme 1).[2][3]

The transformation of unsaturated derivatives by cross-metathesis reactions with alkynes leading to conjugated dienes emphasizing on the utilization of greener dialkyl carbonate solvents will be also presented.[4]

[1] A. Rybak, P. A. Fokou, M. A. R. Meier, Eur. J. Lipid Sci. Technol. 2008, 110, 797-804. [2] X. Miao, R. Malacea, C. Fischmeister, C. Bruneau, P. Dixneuf, Green Chem., 2011, 13, 2911-2919. [3] J.-L. Couturier, J.-L. Dubois, X. Miao, C. Fischmeister, C. Bruneau, P. Dixneuf, PCT Int. Appl. WO 2011138051, 2011

and manuscript submitted. [4] V. Le Ravalec, A. Dupé, C. Fischmeister, C. Bruneau, ChemSusChem. 2010, 3, 1291-1297.

Keywords: Metathesis, Ruthenium, FAMEs

MS.C1.C.01 Diolefin complexes of transition metals as ‘Venus fly-trap’ mimicking templates

Andreas Roodt,a Tania Hill,a Gideon Steyl,a aDepartment of Chemistry, University of the Free State, Bloemfontein 9300, South Africa. E-mail: [email protected] Olefins, and in certain transformations, diolefins in particular, are sometimes produced in a number of petrochemical conversions. In successive downstream processes, these diolefins may interact negatively with catalysts, effectively deactivating and trapping it to such an extent that it is no longer available for participating in the actual catalytic cycle. As part of our ongoing efforts to evaluate structure/ reactivity relationships via detailed fundamental studies, [1] we have in this current investigation identified 1,5-cyclooctadiene as a diolefin model and utilised it as ligand to evaluate its bonding mode in a range of middle to late transition metal complexes. We in particular investigated the opening/ closing of the ‘Venus fly-trap’ angle (y) and the bite angle (c) as defined below, as a function of variants such as metal centre, trans ligand donor atoms, metallocycle size and solid state packing effects.

This presentation thus includes a number of detailed solid state studies from X-ray structure determinations, and accompanying DFT calculations in the case where solid state data could not be obtained. It attempts to rationalise bond strengths of the diolefin bonds in terms of a number of a parameters, and will be discussed in detail in this presentation. The data of some 15 X-ray crystal structures, and the accompanying DFT optimised structures, will be presented. [1] A. Roodt, H.G. Visser, A. Brink. Crystallography Reviews 2011, 17, 241280.

component of growth hormones made in the thyroid gland, ingestion of excess ClO4- causes serious effects on growth of newborns and children. In 2005, the U.S. Environmental Protection Agency (EPA) announced that the acceptable exposure level of this anion was 24.5 parts per billion (ppb) in drinking water. However, reduction of the ClO4- concentration to lower than 25 ppb in short period is a tough subject.[2] We have focused on perchlorate removal from water by using metal complexes.[3] Recently, we have isolated a M2L4 type new molecular capsule [SO4 Cu2(m-bbitrb)4]SO4 (m-bbitrb = 1,3-bis(benzimidazol1-ylmethyl)-2,4,6-trimethylbenzene) (1·SO4), and have found that the compound had high perchlorate removal ability from water by exchange of SO42- outside the cage. The compound was obtained as blue solid from H2O/EtOH mixed solution of CuSO4·5H2O and m-bbitrb. Single crystal X-ray analysis showed that the compound involved SO42- within and outside the cage. Although the compound was not soluble in water, the SO42- outside the cage was exchanged with ClO4- in aqueous media (Figure 1). When 0.20 g (0.10 mmol) of the compound was added to the aqueous solution (100 mL) containing F-, Br-, NO3-, ClO4-, and SO42- at the same concentration (1.0 mM), 1.0 mM of ClO4- was preferentially reduced to about 0.070 mM at 5 min, and then 0.013 mM within 30 min. Other anions, NO3- and Br-, were also reduced from 1.0 mM to about 0.55 mM and 0.80 mM at 30 min. This result demonstrated that the compound can remove ClO4- effectively from aqueous solutions even in the presence of other anions. The compound was fixed in the membrane filter by filtration to prepare a ClO4- removal filter. The preliminary experiment showed that the obtained filter reduced concentration of ClO4- in water from 1000 ppb to about 16 ppb by passing through it.

Figure 1. Perchlorate removal by exchange of SO42- outside the cage.

[1] J. Wolff, Pharmacol. Rev. 1998, 50, 89-105. [2] P. B. Hatzinger, Environ. Sci. Technol. 2005, 39, 239A-247A. [3] T. Hirakawa, M. Yamaguchi, N. Ito, M. Miyazawa, N. Nishina, M. Kondo, R. Ikeya, S. Yasue, K. Maeda, F. Uchida, Chem. Lett. 2009, 38, 290-291. Keywords: perchlorate removal, molecular capsule, anion exchange

Keywords: diolefins, cyclooctadiene, X-ray structures, DFT

MS.C1.C.02 Removal of Perchlorate from Water by using Cationic Molecular Capsule Mitsuru Kondo,a Masaru Mochizuki,b aCenter for Instrumental Analysis, Shizuoka University, Shizuoka (Japan) bDepartment of Chemistry, Shizuoka University, Shizuoka (Japan). E-mail: scmkond@ ipc.shizuoka.ac.jp Perchlorate ion (ClO4-) is quite difficult to remove from aqueous solutions because of its high solubility in water. Since this anion interferes with the thyroid’s uptake of iodide which is an essential

MS.C1.C.03 Using Outer Sphere Coordination Chemistry to Tune the Strength and Selectivity of Metal Extractants Peter Tasker, EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, (UK). E-mail: [email protected] We have manipulated secondary bonding in the outer coordination spheres of metal ions to tune the strength and selectivity of solvent extractants for metal cations,[1] metal salts[2] or metallate anions.[3] Varying the hydrogen bond-buttressing involving a substituent ortho to the phenol group in commercial salicyl-aldoxime Cu-extractants and the oximic OH group (see below) can change the distribution coefficient for copper extraction by two orders or magnitude[1].

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Microsymposia This paper extends the approach to the structurally related salicylhydrazones and uses a combination of X-ray structure determination and DFT calculations to interpret the effects of the buttressing groups and to compare the strength with oxime analogues.

[1] S. Masaoka, K. Sakai, Chem. Lett., 2009, 38, 182. (Time cited 40). [2] M. Yoshida, S. Masaoka, K. Sakai, Chem. Lett., 2009, 38, 702. (Time cited 21). [3] M. Yoshida, S. Masaoka, J. Abe, K. Sakai, Chem. Asian J., 2010, 5, 2369. (Time cited 13). [4] A. Kimoto, K. Yamauchi, M. Yoshida, S. Masaoka, K. Sakai, Chem. Commun., 2012, 48, 239. [5] M. Okamura, M. Yoshida, R. Kuga, K. Sakai, M. Kondo, S. Masaoka, Submitted.

Keywords: Water oxidation, Ruthenium complexes, Protoncoupled electron transfer Hydrogen bonding in the outer coordination spheres of chlorometallates can also be manipulated to enhance recovery in “pHswing” processes, 2Lorg + MClx2- + 2H+ = [(LH)2(MClx)]org. We have a shown[3] that ligands with sterically hindered basic sites make it possible to recover kinetically labile chlorometallates by preventing the ligand from entering the inner coordination sphere. [1] R. S. Forgan, B. D. Roach, P. A. Wood, F.J. White, J. Campbell et al., Inorg, Chem. 2010, 4515-4522. [2] R. S. Forgan, J. E. Davidson, S.G. Galbraith, D. K. Henderson et al., Chem. Commun. 2008, 4049-4050. [3] R. J. Ellis; J. Chartres, D. K. Henderson, Rafel Cabo-Mesquida et al., Chem. Eur. J., 2012, DOI: 10.1002/chem.201103616.

Keywords: solvent extraction, outer sphere, platinum

MS.C1.C.04 Water oxidation catalyzed by mononuclear and multinuclear metal complexes Shigeyuki Masaoka,a,b aInstitute for Molecular Science, Okazaki, (Japan). bPRESTO, Japan Science and Technology Agency (JST), Saitama (Japan). E-mail: [email protected] Visible-light-induced water splitting reaction has attracted much attention due to its potential application toward artificial solar energy conversion and storage. This water-to-fuels conversion consists of the two half-cell reactions, reduction of water to H2 and oxidation to O2. Development of molecular catalysts toward water oxidation is a more serious challenge than that of the reduction side because it requires the removal of four protons and four electrons. Therefore, to develop highly efficient catalysts toward water oxidation is a key to achieve the complete water splitting reaction. In this study, the O2-evolving activities of new ruthenium catalysts have been evaluated using cerium(IV) ammonium nitrate as an oxidizing reagent. During the detailed studies on these systems, it was realized that some mononuclear systems are much higher in activity than the diruthenium ones, raising a question about the importance of a dinuclear character in the O2-evolving catalysis. This finding became a significant breakthrough in this field because it has long been believed that the water oxidation is much more effectively catalyzed by dinuclear or tetranuclear metal complexes. In this talk, recent progress of the study on the O2-evolving catalysis will be reported.

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MS.C1.C.05 From trash to resource: powerful reagents for a green NobleMetals dissolution Angela Serpe,a Flavia Artizzu,a Davide Espa,a Luciano Marchiò,b Maria Laura Mercuri,a Elisa Sessini,a Paola Deplano,a aDipartimento di Scienze Chimiche e Geologiche, Università di Cagliari., Cagliari (Italy), bDipartimento di Chimica Gen e Inorg., Chim. An., Chim. Fis, Università di Parma., Parma (Italy). E-mail: [email protected] In order to balance sustainability with economic development most countries are promoting new strategies on waste management to face the increasing demands on the planet’s limited resources. The goal is to create value from waste, including reuse, recycling, waste–to-energy and recovery without endangering human health and without using processes or methods that could harm the environment. Coordination Chemistry, as largely done in the past for the recovery/refinery of metals from ores, may help in providing suitable tools for metal recovery by waste. In particular, waste may contain precious metals in amount comparable or even higher than in their ores, as it happens for gold in e-waste (e=electronic). Reagents based on dihalogen adducts of cyclic-dithioxamides, which do not show cytotoxicity, are capable of dissolving metal palladium and even gold in a one-step reaction and under mild conditions.[1] Moreover these reagents have proved to be suitable for practical applications, such as for the palladium recovery from model spent three way catalysts (TWC), where even in a complex system such as an exhaust TWC, the metal is selectively and almost quantitatively dissolved. Quite satisfactory results have also been obtained in gold recovery from selected e-waste and from deprocessing procedures for the failure analysis of microelectronic devices. Here we report results of the leaching properties towards elemental gold of a mixture of diiodine and tetraalkylthiuramdisulphide in (CH3)2CO, in order to check their capability to work as suitable coordinationoxidation reagents to be employed for practical use. As shown below, the mixture is capable to dissolve quantitatively elemental gold in mild conditions and, depending on the ratio of the mixture components, different products 1, 2 and 3 have been isolated and fully characterized. Interestingly in compound 1, both gold(III) and gold(I) are present.

Microsymposia

These results show that the leaching mixture is very effective in dissolving gold in mild conditions. Experiments for recovering elemental gold from the complexes are in course. It is noteworthy that the obtained products have an intrinsic interest, since gold dithiocarbamates are under investigation as anticancer agents.[2] [1] A. Serpe, M. L. Mercuri, L. Pilia, P. Deplano , Coord. Chem. Rev., 2008, 252/10-11,1200-1212, and refs. cited therein.[2] L. Cattaruzza, D. Fregona, M. Mongiat, L. Ronconi, A. Fassina, A. Colombatti, D. Aldinucci, International J. of Cancer, 2011, 128, 1, 206–215.

Keywords: Noble-Metals, Halogen/S-donor Adducts, Recovery

MS.C1.C.06 Macrocyclic Tetraamidate Iron Complexes as Green Oxidation Catalysts L. James Wright,a Terrence J. Collins,b Brendan D. Harvey,a Laura G. Raymond,c Trevor R. Stuthridge,c aSchool of Chemical Sciences, University of Auckland, Auckland (New Zealand). bDepartment of Chemistry, Carnegie Mellon University, Pittsburgh, PA (USA). cScion Ltd., Rotorua (New Zealand). E-mail: [email protected] Oxidation chemistry plays a central role in many large industrial processes. In situations where chlorine-based oxidants are used in conjunction with organic compounds the formation of potentially harmful organo-chlorine compounds is often an inevitable side reaction. Hydrogen peroxide is an inexpensive alternative oxidant that does not pose this problem and accordingly it is often referred to as a “green oxidant”. However, the oxidation of organic compounds by H2O2 typically proceeds very slowly because of the high kinetic barriers to these reactions. This problem can be overcome through the development of suitable catalysts that increase the rates and selectivity of these reactions. In a long-term iterative design and testing process Prof. Collins and his group have developed the macrocyclic tetraamidate iron complex (FeB*) shown in Figure 1 [1]. This compound is an excellent catalyst for the oxidation of organic compounds with H2O2. It is moderately simple to prepare, contains non-toxic elements, is water soluble, has high activities (< 1 mmol L-1), and utilises H2O2 efficiently. The FeB*/H2O2 oxidation system therefore provides an attractive Green Chemistry alternative to chlorine-based oxidants where the formation of unwanted organochlorines is problematic [2]. An important feature of the tetraamidate macrocyclic ligand in FeB* is that it is amenable to chemical modification. Since it is known that the dimethylmalonamide part of the macrocycle is susceptible to rupture under oxidative stress, we have recently designed and synthesised a new tetraamidate macrocyclic ligand in which this section has been replaced with an oxalamide group. In the iron complex of this new ligand, FeBJ (see Figure 1), the contracted ring size and modified donor properties of the deprotonated oxalamide nitrogens alter the catalytic activity and behaviour. Compared with FeB* this new complex is much less prone to demetalation by acid, is more stable in the activated form, and catalyses oxidations by H2O2 in less strongly alkaline solutions. However, the rates of oxidation of organic molecules are slower. Unlike H4B*, the aromatic ring of the free macrocycle H4BJ is easy to functionalise and this provides a

[1] T. J. Collins, Acc. Chem. Res. 2002, 35, 782-790. [2] C. P. Horwitz, T. J. Collins, J. Spatz, H. J. Smith, L. J. Wright, T. R. Stuthridge, K. G. Wingate, K. McGrouther, Iron-TAML Catalysts in the pulp and paper industry, ACS Symposium Series, (2006) 921 (Feedstocks for the Future) Edited by J. J. Bozell and M. K. Patel, pp156-169.

Keywords: catalysts, oxidation, iron

MS.C1.C.07 Transition Metal Amine-bis(phenolate) Complexes as Catalysts for the Copolymerization of CO2 and Epoxides Christopher M. Kozak,a aDepartment of Chemistry, Memorial University of Newfoundland, St. John’s, (Canada). E-mail: ckozak@ mun.ca The reaction of CO2 and epoxides to give cyclic carbonates or polycarbonates is a promising method of utilizing CO2 as a C-1 feedstock. The preparation and catalytic CO2 activation activity of chromium and cobalt complexes of tripodal amine-bis(phenolate) ligands will be presented. By tuning the reaction conditions, the catalysts can be made selective for either cyclic carbonate or polycarbonate formation using cyclohexene oxide or propylene oxide as co-monomer.[1] The ligands used allow for high degree of tunability in the number of donor groups, the steric and electronic nature of the donors, and the coordination geometry around the metal centre.

[1] L. N. Saunders, N. Ikpo, C. F. Petten, U. Kumar Das, L. N. Dawe, C. M. Kozak and F. M. Kerton. Catal. Commun. 2012, 18, 165.

Keywords: Catalysis, Copolymerization, CO2 activation

MS.C1.C.08 Green Chemical Synthesis of Polynuclear 3d-4f Complexes Bridged by Amino Acidato Ligands Yasuhiko Yukawa,a Satoshi Igarashi,b Guillem Aromí,c Olivier Roubeau,d Floriana Tuna,e aFaculty of Science, Niigata University, Niigata, (Japan). bFaculty of Education, Niigata University, Niigata (Japan). cDepartment de Química Inorgànica, Universitat de Barcelona (Spain), dDepartamento de Física, Universidad de Zaragoza (Spain), eNational EPR Facility, Photon Science Institute, University of

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convenient way to rationally alter the properties of the resulting iron complexes. The syntheses, properties and catalytic oxidation studies of FeBJ and its derivatives that bear different aromatic substituents will be presented.

Microsymposia Manchester (United Kingdom). E-mail: [email protected]

MS.C1.C.09

Heteronuclear complexes have attracted special attention because of their versatile magnetic behaviour, as well as being single molecule magnets or magnetic refrigerants. To synthesize the complexes many excellent ligands have been designed and prepared by ingenious processes of organic syntheses. Sometimes, however, the synthesis of the ligands is not green chemical: it often brings a lot of waste and energy loss. An amino acid, which is safe and easily obtained, can be regarded as a typical multidentate ligand. Taking advantage of the properties of the amino acidato ligand, we have been carrying out the syntheses of heteronuclear complexes bridged by amino acidato ligands: a simple amino acidato transition metal complex has been used as a building block to synthesize new polynuclear 3d-4f complexes. Bis(amino acidato)metal complexes are at equilibrium in a solution as shown in scheme 1. The cis-complex would act as a “ligand” to any metal ion which is harder than a transition metal, such as lanthanide, alkaline, or alkaline earth metal. By controlling synthetic conditions, such as ratio of metals, combination of metals and amino acids, various complexes which have different structures and properties are easily obtained. Here we demonstrate three types of 3d-4f complexes: Ni6-Gd, Ni2Gd2 and Ni6-Gd2. The firs, Ni6-Gd, contains a central icosahedrally coordinated Gd surrounded by an octahedron of Ni centres, the second is an alternately cyclic tetranuclear Ni2Gd2 complex and the third is dinuclear Gd complex encapsulated by two of Ni3 moieties. Measurements of magnetic properties of these complexes showed that the presence of a large spin ground state: S = 13/2 for Ni6-Gd, S = 9 for Ni2-Gd2 and S = 13 for Ni6-Gd2. We made a preliminary evaluation of the potential of Ni2-Gd2 and Ni6-Gd2 for magnetic refrigeration, through the determination of the magnetic entropy change, ΔSm, from the magnetization data for selected field changes, ΔB. The results show that −ΔSm increases gradually as ΔB increases and T decreases, to reach a value of 27.5 J kg−1 K−1 at T=3 K and ΔB=7 T for Ni2-Gd2, and 17.6J kg−1 K−1 at T=3 K and ΔB=5 T for Ni6-Gd. In summary, amino acids have been confirmed to be a varied and versatile class of ligands for the preparation of 3d-4f heterometallic clusters. Preliminary magnetic studies show that Ni2-Gd2 and Ni6-Gd2 would be a good magnetic refrigerant for low-temperature applications.

Proton Reduction Catalysis at Iron Dimers with FerrocenylPhosphido Bridges Carolina Gimbert-Suriñach,a Mohan Bhadbhade,b Stephen B. Colbran,a aSchool of Chemistry and bMark Wainwright Analytical Centre, University of New South Wales, Sydney, NSW 2052 (Australia). E-mail: [email protected] [FeFe]-Hydrogenases are excellent proton reduction catalysts with turnovers of the order of 6000-9000 mol of H2/mol catalyst at less than 100 mV overpotential [1]. The enzyme cofactor is a unique diiron cluster, which has been the inspiration of many scientists giving rise to more than 250 new compounds mimicking its structure [2]. As a result, insights into the hydrogen evolution mechanism have been achieved, but many issues regarding inter-relationships between structure, overpotential, mechanism, and catalyst stability and efficiency remain to be addressed. This work focuses on the synthesis and study of hydrogenase analogs containing ferrocenyl pendants and primary phosphido bridges. The ferrocenyl groups are potential electron donors and act as internal electrochemical standard [3]. The diphosphido cluster {µ-P(H)(CH2Fc)}2Fe2(CO)6 (Fc = ferrocenyl) (1) was obtained from reaction of the corresponding primary phosphine and iron carbonyl. Typically (µ-PR2)2Fe2Lx diiron “butterflies” display a two-electron reduction process to afford the corresponding (µ-PR2)2Fe2Lx2– dianion in which the Fe-Fe bond is cleaved and the butterfly structure opened and flattened [2b,c]. In stark contrast, dimer 1 reveals a one-electron reduction that ultimately gives the anion [{µ-P(CH2Fc)}{µ-P(H)(CH2Fc)}Fe2(CO)6]– ([1 – H]–). The formation of [1 – H]– upon one-electron reduction of 1 requires homolytic fission of the P—H bond to give a molecule of H2 (formally loss of a hydrogen atom) and therefore represents a novel pathway for hydrogen evolution. Deprotonation of 1 gives a reactive intermediate, [(µ-PCH2Fc)2Fe2(CO)6]2–, that easily allows functionalisation of the cluster. New derivatives with potentially enhanced catalytic efficiencies towards hydrogen evolution will be presented.

[1] (a) C. Tard, C. J. Pickett, Chem. Rev. 2009, 109, 2245. (b) M. Frey, ChemBioChem 2002, 3, 153. [2] (a) G. A. N. Felton, C. A. Mebi, B. J. Petro, A. K. Vannucci, D. H. Evans, R. S. Glass, D. L. Lichtenberger, J. Organom. Chem. 2009, 694, 2681. (b) M. H. Cheah, S. J. Borg, M. I. Bondin, S. P. Best, Inorg. Chem. 2004, 43, 5635. (c) M. H. Cheah, S. J. Borg, S. P. Best, Inorg. Chem. 2007, 46, 1741. [3] C. Gimbert-Suriñach, M. Bhadbhade, S. B. Colbran, Organometallics 2012, DOI: 10.1021/om201126w. Scheme 1. Equilibrium between trans- and cis- bis(amino acidato)metal complexes in a solution.

Keywords: amino acidato ligand, 3d-4f complex, magnetic properties

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Keywords: diiron cluster, phosphido ligand, proton reduction

Microsymposia MS.C1.C.10 Activating Di-hydrogen by Borabenzene: A Frustrated Lewis Pair Partner Manab Sharma, Anthony F. Hill Research School of Chemistry, The Australian National University, Canberra, Australian Capital Territory 0200, Australia. E-mail: [email protected]

MSC1

In a remarkably short time, the ‘Frustrated Lewis Pair’ (FLP) concept of frustrated Lewis pairs has been widely embraced,1 primarily because this unusual situation is not just a fundamental curiosity, but rather opens up new avenues of reactivity, mostly in the activation of dihydrogen.2 Although free borabenzene remains elusive, numerous examples of Lewis base adducts have been described. Therefore, we computationally investigated the possibility of borabenzene (1)3 playing a role in dihydrogen activation being an agent of FLP. The combination of the two frontier orbitals resemble a situation of transition metals where, given a suitable d-occupancy, the metal is a capable of acting as both a s-acceptor and a p-retrodonor to an incoming ligand, including dihydrogen. The study of the activation of hydrogen by borabenzene, strong Lewis acid, in presence of Lewis bases, N-methylimidazoleylid (NHC) reveals that the process is highly exothermic with an initial activation barrier of ~31 kJ/mol only.

[1] Stephan, D. W.; Erker, G. Angew. Chem., Int. Ed. 2010, 49, 46. [2] Welch, G. C.; Stephan, D. W. J. Am. Chem. Soc. 2007, 129, 1880-1881; Welch, G. C.; Juan, R. R. S.; Masuda, J. D.; Stephan, D. W. Science 2006, 314, 1124-1126. [3] Herberich, G. E.; Ohst, H. Adv. Organomet. Chem. 1986, 25, 199; Fu, G. C. Adv. Organomet. Chem. 2001, 47, 101; Cade, I. A.; Hill, A. F. Dalton Trans. 2011, 10563.

Keywords: Dihydrogen activation, Borabenzene, Frustrated Lewis Pair

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MS.C2.KN2

Organometallic Catalysts for Olefin Polymerization Guo-Xin Jin, Department of Chemistry, Fudan University, Shanghai 200433, China. E-mail: [email protected]

Transition Metal Ions in Mesoporous Structures for Oxidation of Hydrocarbons Bao-Lian Su,a Viorica Parvulescu,b aLaboratory of Inorganic Materials Chemistry, University of Namur (FUNDP), (Belgium). bDepartment Institute of Physical Chemistry, Romanian Academy of Sciences, (Romania). E-mail: [email protected]

Recent years have witnessed dramatic advances in the design and applications of organometallic catalysts for olefin polymerization. A variety of half-sandwich transition metal complexes with the hemilable ligands which contain both strong and weak donor groups have been synthesized and characterized structurally.[1] The hemilabile arm in such ligands is capable of reversible dissociation from the metal center. Such dynamic behavior will produce vacant coordination sites that allow complexation of substrates during the catalytic cycle, at the same time the strong donor moiety remains connected to the metal center. The possibility of functionalizing the nitrogens in salicylaldiminato ligand makes them suitable for the generation of hemilabile ligands. Hence these complexes have been found widespread use in homogeneous catalysis for olefin polymerization in the presence of methylalumoxane (MAO) as co-catalysts. The half-sandwich iridium complexes were synthesized by the reaction of [Cp*IrCl(m-Cl)]2 (Cp* = h5-pentamethyl-cyclopentadienyl) with the corresponding lithium salts of the hemilable ligands. The Ir complexes can be employed for norbornene polymerization and shown moderate activities. The studies of the polymers indicate that: lowMAO catalyst produces ROMP polymer, while the high-MAO catalyst initiates vinyl-type polymerization.

Transition metals (TMt) play a vital role in the selective oxidation of organic molecules. A large series of single (Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Nb, Ru, La, W and Ta) and bimetallic (V-Ti, V-Co, V-Cu, CrNi, Cr-Ru, Ni-Ru, Ni-Ti, Cu-Ru, Co-La, La-Mn, Ti-Nb and Co-Nb) ions incorporated highly ordered mesoporous silica nanostructures have been investigated as efficient catalysts for liquid phase selective oxidation of alcohols, olefins and aromatics. Some of single metal ions incorporated mesoporous structures give a high catalytic conversion, but low selectivity and others led to the inverse results. The combination of two different metal ions can create new catalysts with different or new redox and acid properties and has been explored. The catalytic activity and selectivity has been correlated with the coordination chemistry of metal ions in the framework and type of reagents (alcohol, olefin or aromatic). The effect of the presence of a second metal ion on the activity and selectivity will be presented. Keywords: Metal ions, Mesoporous silicas, Selective oxidation

MS.C2.I1 The Structure-Activity-Function (SAF) of Multidentate Hybrid Ligands in Catalysis T. S. Andy Hora,b, F. Xuea, X.-L. Songa, Z. Wanga, L. Jianga, S. W. Chiena, J. Zhaoa,b, S. Q. Baib, W.-H. Zhangb and Y. Zong,b aDepartment of Chemistry, National University of Singapore, 3 Science Drive 3, S 117543(Singapore). bInstitute of Materials Research & Engineering, Agency for Science, Technology & Research, 3 Research Link S 117602 (Singapore). E-mail: [email protected]

Pure ROMP polymer and vinyl-type polymer were obtained depending on the amount of MAO. This interesting behavior not only provides a promising iridium catalyst for ROMP and vinyl polymerization of norbornene for the first time, but also shed lights on copolymerization of norbornene with ROMP and vinyl-type by changing the co-catalyst ratio.[2] [1]. a). J. Zhang, X. Wang, G-X. Jin Coord. Chem. Rev., 2006, 250, 95; b). Y-F. Han, W-G. Jia, G-X. Jin, Chem. Soc. Rev., 2009, 38, 3419; c). X. Wang, G-X. Jin, Chem. Euro. J., 2005, 11, 5758; d). A-Q. Jia and G-X. Jin, Organometallics, 2009, 28, 1872; e). P Hu, J-Q. Wang, F-S. Wang and G-X. Jin, Chem. Euro. J., 2011, 17, 8576; f). Z-J. Yao, G. Su, G-X. Jin, Chem. Euro. J., 2011, 17, 13298 (). [2]. a). X. Wang, S. Liu, G-X. Jin, Organometallics, 2006, 25, 3565; b). C. Guo, D. Zhang, F. S. Wang, G-X. Jin, J. Catal. 2005, 234, 356; c). Y-F. Han, W-G. Jia, G-X. Jin, Angew. Chem. Int. Ed., 2009, 48, 6234; d). P. Hu, Z-J. Yao, J-Q. Wang, G-X. Jin, Organometallics, 2011, 30, 4935; e). P. Hu, F. S. Wang, G-X. Jin, Organometallics, 2011, 30, 1008; f). Meng, G. R.Tang, G-X. Jin, ChemComm., 2008, 3178.

Hybrid ligands that carry hetero-donors are particularly effective in stabilising complexes in which the metal center(s) are in a dynamic state that require different sets of donor functions under different (steric and electronic) conditions.[1] When these ligands are further equipped with multidentate capability, they offer additional protection to active intermediates that are coordinatively exposed at different stages of catalytic cycle. Our focus in recent years is the design-andbuild of new materials[2] that can be potentially applied to challenging catalytic organic transformation.[3] (Refer to the figure below for a typical complex). In this presentation, we shall highlight our latest development, including those that have not been published and in press, and explain how these hybrid ligands can add invaluable structural flexibility and adaptability.

Keywords: Organometallic Catalysts, Olefin Polymerization

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Microsymposia [1] W.-H. Zhang, S. W. Chien, T. S. A. Hor, Coord. Chem. Rev., 2011, 255, 1991-2024. [2] S.-Q. Bai, A. M. Yong, J. J. Hu, D. J. Young, X. H. Zhang, Y. Zong, J. W. Xu. J. L. Zuo, T. S. A. Hor, Cryst. Eng. Comm., 2012, 14, 961-971. [3] F. Xue, J. Zhao, T. S. A. Hor, Dalton Trans., 2011, 40, 8935-8940.

Keywords: catalysis, multidentate, hybrid ligand

[1] P. T. Anastas, J. B. Zimmerman, Environ. Sci. Technol., 2003, 37, 94A. [2] Selected papers: a) J. A. Brito, S. Ladeira, E. Teuma, B. Royo, M. Gómez, Appl. Catal. A: General, 2011, 398, 88; b) I. Favier, A. Balanta Castillo, C. Godard, S. Castillón, C. Claver, M. Gómez, E. Teuma, Chem. Commun., 2011, 47, 7869. [3] Selected review: A. E. Diaz-Alvarez, J. Francos, B. Lastra-Barreira, P. Crochet, V. Cadierno, Chem. Commun., 2011, 47, 6208. [4] A. Zanardi, R. Corberan, J. A. Mata, E. Peris, Organometallics, 2008, 27, 3570.

MS.C2.I2

Keywords: green solvents, ligand design, metal-catalyzed multistep synthesis

New metallic catalytic systems for applications in tandem processes Montserrat Gómez. aLaboratoire Hétérochimie Fondamentale et Appliquée, UMR CNRS 5069, University Paul Sabatier, Toulouse (France). E-mail: [email protected]

MS.C2.I3

The synthesis of molecules showing an interest for the fine chemistry industry following sustainable protocols is one of the most important challenges since the beginning of XXI century [1]. In this context, metal-catalyzed organic transformations represent an appropriate tool because they permit to work under smooth conditions (low energetic cost) and to minimise the by-products formation (atom economy). In the last decade, alternatives to the organic volatile solvents commonly used, have been studied: water, supercritical fluids, perfluorinated solvents, ionic liquids [2]. However, their general use is still subject to some limitations (solubility issues, toxicity and non-biodegradability constraints, separation of products). Glycerol, a low-cost solvent coming from biomass, currently produced in high amounts as a waste in the biodiesel production and showing interesting properties (high boiling point, negligible vapour pressure, high solubility of organic and inorganic compounds), has specially attracted our attention [3]. Here, we will present in particular the reactivity for Rh-catalyzed Pauson-Khand carbocyclisations in neat glycerol. Surprisingly, the nature of the organometallic precursor and the Rh/ligand ratio trigger dramatic effects on the catalytic activity in contrast to that observed using coordinating organic solvents. A NMR study will be shown in order to reveal the role of glycerol. In our group, we are also interested in the design of ligands involving original skeletons, able to give different kind of interactions with the metallic centers, leading to an attractive topic to study new coordination modes and cooperative effects, mainly interesting for metal-catalyzed multi-step syntheses [4]. From this perspective, we have studied the coordination of original ligands coming from 9,10-dihydroanthracene succinic acid anhydrides (I), versatile frames which permit both to easily modulate the anhydride part and favor the p-coordination through the aromatic rings. Preliminary results concerning the catalytic behavior of these complexes will be also discussed.

Selective Oxidation with Non Porphyrinic Fe and Mn Complexes that Support High Oxidation States Miquel Costas, Julio Lloret-Fillol, Irene Prat, Zoel Codolà, Laura Gómez, Isaac García-Bosch, Anna Company, Olaf Cussó, Mercè Canta, Xavi Ribas, David Font, Institut de Quimica Computacional and Departament de Química.,Universitat de Girona, Girona, (Spain). E-mail: [email protected]. The formation and cleavage of the O-O bond is arguably the most important reaction in living organisms. Reductive O-O breakage takes place in cytochrome C oxidase.[1] This reaction constitutes the basic constituent of cellular respiration in aerobic organisms, and represents a primary source of energy. O-O cleavage also takes place in oxygenases,[2] and this reaction results in the generation of highly electrophilic high valent metal-oxo species, responsible for oxidative transformations. On the other hand, O-O bond formation takes place at a Mn4Ca cluster in the Oxygen Evolving Center of Photosystem II (PSII) of green plans and some bacteria. In both oxidative and respiration enzymes, metal ions adopting high oxidation states result from reductive O-O cleavage reactions while in PSII they are responsible for O-O bond formation.[3] Selected coordination complexes that reproduce structural aspects of enzymatic active sites have been shown to catalyze analogous reactions, and recently some of these complexes have turned into very attractive tools for organic synthesis.[4] In addition, the study of the mechanisms of action of these catalysts has shed light into the molecular details of enzymatic systems. Our research group undertakes this approach and aims at studying the chemistry of iron and manganese coordination complexes with chemically robust nitrogen-based ligands, and which can sustain high oxidation states and that can act as catalysts for very challenging reactions such as the selective oxidation of alkyl C-H bonds,[5] the cis-dihydroxylation of alkenes,[6] stereoselective epoxidation[7] and the oxidation of water. [7] Recent progress from our group will be discussed.

Acknowledgements: Generalitat de Catalunya (ICREA Academia and SGR 2009-SGR637), MICINN (CTQ 2009-08864 and Consolider Ingenio CSD2010-00065), ERC-StG-239910.

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Keywords: Bioinspired Catalysis, Oxidation, High-Valent

MS.C2.C.01 Pd(II)-catalyzed cicloisomerization of alkynoic acids in water. New tandem cicloisomerization/click chemistry reactions Joaquín García-Álvarez,* Josefina Díez, José Gimeno, Cristian Vidal, Departamento de Química Orgánica e Inorgánica (IUQOEM) Universidad de Oviedo, Julián Clavería 8, E-33006 Oviedo (Spain). E-mail: [email protected] The search for organic reactions proceeding with efficiency, selectivity and atom economy (i.e., all atoms of the reactants end up in the final product), has emerged as a major goal in synthetic chemistry [1]. Isomerization reactions are typical examples of atom economic processes as no by products are generated. In this sense, the catalytic cicloisomerization of γ-alkynoic acids (1) promoted by transitionmetals represents a straightforward route to synthetically useful cyclic enol-lactones (2). It is important to note that, in most of the cases, this catalytic transformation has only been carried out in organic solvents or in biphasic mixtures with water [2]. In this communication, we will present a simple and versatile iminophosphorane-Pd(II) complex 3, as catalyst for the rapid and efficient cicloisomerization of both terminal and internal γ-alkynoic acid (1) into their corresponding enol-lactones (2), in water, at room temperature and under air. In addition, the catalytic system could be also recycled in ten consecutive runs. Application of this methodology to the new tandem cicloisomerization/click chemistry reaction will be also discussed.

MS.C2.C.02 2-Indenylidene Pincer Complexes: From non-innocent behavior to Metal / Ligand Cooperative Catalysis Blanca Martín-Vaca, Noel Nebra, Jérôme Lisena, Rosie Shaw, Didier Bourissou, Laboratoire Hétérochimie Fondamentale et Appliquée UMR CNRS 5069, Université Paul Sabatier, Toulouse, (France). E-mail: [email protected] Pincer complexes have attracted an upsurge of interest in the last few years as a result of their particular balance between stability and reactivity. Tuning the ligand structure has given rise to a huge variety of pincer complexes. Those promoting original catalytic transformations involving metal / ligand cooperativity can be particularly highlighted. [1] In this context, we have recently reported a novel family of pincer ligands, consisting in an indene or indole skeleton bearing two coordinating side-arms on positions 1 and 3. The introduction of these donor groups has enabled the preparation of pincer complexes featuring unusual coordination modes between the indene ring and the metal such as h1-2-indenyle (1) and h1-2-indenylidene (2).[2] The particular bonding situation evidenced for complexes of type 2 results in a non-innocent behaviour of the pincer ligand, that has been demonstrated by the direct involvement of the ligand back-bone in the reaction with organic and metallic electrophiles.[3] We are now interested in taking advantage of this non-innocent behaviour in catalytic transformations, and the presentation will focus on the last results achieved in this field. The intramolecular addition of carboxylic acids to alkynes leading to lactones, catalysed by h1-2-indenylidene complexes (2), has been chosen as a model transformation. The scope of the reaction will be presented and a particular attention will be paid to the mechanistic investigations that strongly support a mechanism involving metal / ligand cooperativity.

[1] Gunanathan, C.; Milstein, D. Acc. Chem. Res. 2011, 44, 588. [2] (a) Oulié, P.; Nebra, N.; Saffon, N.; Maron, L.; Martin-Vaca, B.; Bourissou, D. J. Am. Chem. Soc. 2009, 131, 3493; (b) Nebra, N.; Lisena, J.; Saffon, N.; Maron, L.; Martin-Vaca, B.; Bourissou, D. Dalton Trans. 2011, 40, 8912. [3] (a) Nebra, N.; Saffon, N.; Maron, L.; Martin-Vaca, B.; Bourissou, D. Inorg. Chem. 2011, 50, 6378; (b) Oulié, P.; Nebra, N.; Ladeira, S.; Martin-Vaca, B.; Bourissou, D. Organometallics 2011, 30, 6416; (c) Nebra, N.; Ladeira, S.; Maron, L.; MartinVaca, B.; Bourissou, D. Chem. Eur. J. 2012 in press.

Keywords: Pincer complex, Cooperative catalysis, Indenyle

MS.C2.C.03

[1] (a) B. M. Trost, Science, 1991, 254, 1471-1477. (b) B. M. Trost, Angew. Chem. Int. Ed. Eng., 1995, 34, 259-281. (c) B. M. Trost, M. U. Frederiksen, M. T. Rudd, Angew. Chem. Int. Ed., 2005, 44, 6630-6666. [2] (a) T. L. Mindt, R. Schibli, J. Org. Chem., 2007, 72, 10247-10250. (b) J. Aleman, V. del Solar, C. Navarro-Ranninger, Chem. Commun., 2010, 46, 454-456. (c) J. Aleman, V. del Solar, C. Martín-Santos, L. Cubo, C. Navarro-Ranninger, Eur. J. Org. Chem., 2011, 76, 72877293.

Keywords: Palladium, Cicloisomerization, Aqueous-media

Highly active magnesium catalysts for polycarbonates from CO2 and epoxides Michael R. Kember,a Charlotte K. Williams,a aDepartment of Chemistry, Imperial College London, London (UK). E-mail: m.kember07@ imperial.ac.uk The use of carbon dioxide as a renewable source of chemicals and fuels is very attractive as it is non-toxic, cheap and the waste product of many industries. The thermodynamic stability of CO2 makes its activation and transformation into useful chemicals challenging; low-energy activation of CO2 at ambient pressure (1 bar) is yet more difficult. Energy efficient, low-pressure catalytic transformations of CO2 are very rare and potentially very valuable. The low pressure

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[1] S. Ferguson-Miller, G. T. Babcock, Chem. Rev. 1996, 96, 2889-2907. [2] a) M. Costas, M. P. Mehn, M. P. Jensen, L. Que, Jr., Chem. Rev. 2004, 104, 939-986. B) B. J. Wallar, J. D. Lipscomb, Chem. Rev. 1996, 96, 2625-2658. C) E. I. Solomon, et al. Angew. Chem. Int. Ed. 2001, 40, 4570. d) S. Shaik, et al. Chem. Rev. 2010, 110, 949-1017. e) E. G. Kovaleva, J. D. Lipscomb, Nat. Chem. Biol. 2008, 4, 186-193. [3] Y. Umena, K. Kawakami, J.-R. Shen, N. Kamiya, Nature 2011, 55. [4] a) L. Que, W. B. Tolman, Nature 2008, 455, 333-340. b) A. Company, et al. in Iron-Containing Enzymes, Versatile Catalysts of Hydroxylation Reactions in Nature (S. P. De Visser, D. Kumar), RSC, Cambridge, 2011. [5] a) A. Company et al. J. Am. Chem. Soc. 2007, 129, 15766. b) L. Gomez et al Angew. Chem. Int. Ed. 2009, 48, 5720. [6] a) A. Company et al. Chem. Eur. J. 2008, 14, 5727. b) I. Prat et al. Nat. Chem. 2011, 3, 788. [7] I. Garcia-Bosch Adv. Synth & Cat. 2012, 354, 65. [8] J. Lloret-Fillol Nat. Chem. 2011, 3, 897.

Microsymposia copolymerisation of epoxides and CO2, which produces aliphatic polycarbonates, is a notable reaction.[1] Aliphatic polycarbonates have properties suitable for uses such as adhesives, packaging, elastomers and rigid plastics. Low molecular weight polycarbonate polyols are also precursors for the synthesis of polyurethanes, enabling transformation of CO2 into insulation foams. We have reported a series of di-zinc[2] and di-cobalt[3] catalysts based upon a macrocyclic pro-ligand, which showed excellent activity for the copolymerization of cyclohexene oxide (CHO) and CO2. These catalysts were particularly notable for their activity under low CO2 pressures (1 bar), producing poly(cyclohexene carbonate) (PCHC) with >99 % CO2 incorporation and high selectivity for PCHC (vs. cyclic carbonate). We have been particularly interested to explore the reactivity of different metals for this catalysis, as few metals are known to produce active catalysts. Most recent active catalysts use expensive, toxic cobalt; we were keen to explore cheaper, more biocompatible metals. We herein report the first highly active catalysts for this copolymerization based upon magnesium (see Fig. 1), which is biocompatible and inexpensive. The catalysts are analogous to our previously reported dizinc complexes, but show activity up to six times greater than zinc. The catalysts give greater selectivity for polymer (>99 %) than zinc, even at just 1 bar CO2 pressure and are highly tolerant of water; in fact water can be used instead of organic alcohols or acids as a renewable chain-transfer agent in the production of low-weight PCHC polyols for polyurethane synthesis.

Atom Transfer Radical Polymerisation (ATRP) is a relatively young but strongly emerging polymerisation method, which allows the synthesis of well-defined polymers with regard to their composition, architecture and functionality. The basis of the ATRP process is an equilibrium between a dormant species and the free radical species, which is propagating. The activation and deactivation reaction is catalysed by a transition metal complex which has to be stabilised by a suited ligand.[1,2] Guanidine ligands are known to be strong N donor ligands [3] and copper- hybridguanidine complexes mediate fast and controlled ATRP with narrow weight distributions of obtained polymers.[4] Now, we use guanidine-pyridine systems [5] in an integrated approach of synthetic, electrochemical and theoretical efforts together with the evaluation of the polymerisation performance. These copper complexes are very robust to polymerisation conditions what is advantageous for industrial use. Especially the ligand 1,1,3,3-tetramethyl-2-(quinolin-8-yl)guanidine (TMGqu) convinces with an excellent polymerisation control. In comparison to 1,3-dimethylimidazolidin-2-yliden-(quinolin-8-yl)guanidine) (DMEGqu) with only slightly modified guanidine moiety, we could correlate the ATRP performance with structural features of the copper(I) and copper(II) complexes involved in the ATRP equilibrium. Furthermore, we investigated in detail the electrochemistry of the copper complexes and determined the ATRP equilibrium and the activation constant kact via UV/Vis spectroscopy and SEC. Density functional theory provides additional insights into the ligand influence by calculations on bond dissociation energies and the ATRP equilibrium constant.

[1] Kember, M. R.; Buchard, A.; Williams, C. K. Chem. Commun. 2011, 47, 141-163. [2] Kember, M. R.; Knight, P. D.; Reung, P. T. R.; Williams, C. K. Angew. Chem., Int. Ed. 2009, 48, 931-933; Jutz, F.; Buchard, A.; Kember, M. R.; Fredriksen, S. B.; Williams, C. K. J. Am. Chem. Soc. 2011, 133, 1739517405. [3] Kember, M. R.; Jutz, F.; Buchard, A.; White, A. J. P.; Williams, C. K. Chem. Sci. 2012, 3, 1245-1255; Kember, M. R.; White, A. J. P.; Williams, C. K. Macromolecules 2010, 43, 2291-2298.

Keywords: CO2, polymers, catalysis

MS.C2.C.04 Novel efficient ATRP catalysts through an integrated ligand design strategy Sonja Herres-Pawlisa,b Olga Bienemannb, Ines dos Santos Vieirab Department of Chemistry, Ludwig-Maximilians-Universität München, Munich (Germany). bFakulty of Chemistry, Technical University Dortmund, Dortmund (Germany). E-mail: sonja.herres-pawlis@cup. uni-muenchen.de

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[1] K. Matyjaszewski, T.P. Davis in Handbook of Radical Polymerization, Wiley-Interscience, Hoboken, 2002. [2] A. H. E. Müller, K. Matyjaszewski, Controlled Radical Polymerization, Wiley-VCH, Weinheim, 2009. [3] O. Bienemann, A. Hoffmann, S. Herres-Pawlis, Inorg. Chem. Rev. 2012, 31, 83-108. [4] O. Bienemann, R. Haase, A. Jesser, T. Beschnitt, A. Döring, D. Kuckling, I. dos Santos Vieira, U. Flörke, S. Herres-Pawlis, Eur. J. Inorg. Chem. 2011, 2367-2379. [5] J. Börner, I. dos Santos Vieira, A. Pawlis, A. Döring, D. Kuckling, S. Herres-Pawlis, Chem. Eur. J. 2011, 17, 4507–4512.

Keywords: Atom transfer radical polymerisation, Guanidine, Copper

MS.C2.C.05

MS.C2.C.06

Hydrogen Storage and Delivery: The Carbon Dioxide – Formic Acid Couple Gábor Laurenczy, École Polytechnique Fédérale de Lausanne (EPFL), Institut des Sciences et Ingénierie Chimiques (ISIC), Lausanne, Switzerland. E-mail: [email protected]

“Building” of cage cobalt complexes as electrocatalysts for H2 evolution from water Yan Voloshin, Alexander Dolganov, Alexander Belov, Yurii Bubnov, Nesmeyanov Institute of Organoelement Compounds of the Russian Academy of Sciences, Moscow (Russia). E-mail: [email protected]

The rising energy demand for transport, mobility is presently met by ever increasing use of fossil fuels, while the resulting CO2 emissions lead to global warming with all its environmental and socio-economic consequences. A solution could be the use of H2 as an energy vector for transport: with high fuel cell efficiencies to convert chemical energy into electricity; having water as the only direct by-product; seems to be an option. However current hydrogen storage technologies have weight and safety issues. CO2 and carbonates represent an abundant, cheap, and nontoxic C1 source. The first product of the stepwise reduction of CO2 with H2 is the formic acid [1-4], suggesting this system suitable for hydrogen storage. Numerous platinum group metal complexes catalyse the reduction of CO2 to formic acid in organic solvents, in water, in ILs or in biphasic systems. Despite of the fact that these noble metals are the most efficient today in the CO2/HCO3- hydrogenation, it has been shown recently, that the iron(II) complexes are also active [5], opening a new perspective to use the abundant and inexpensive iron based catalysts. Formic acid is considered as one of the most promising material for hydrogen storage today. Not only does its usable content of hydrogen (4.4 w%) surpass the storage materials used today, it also readily decomposes into H2 and CO2 in the presence of a suitable catalyst [6-8]. The selective homogeneous catalytic decomposition of formic acid in aqueous solution can be carried out using hydrophilic ruthenium-based catalysts, under mild experimental conditions. Recently cheap first row transition metal complexes – Fe(II) with tris[(2-diphenylphosphino) ethyl]phosphi-ne (PP3) ligand (Fig. 1) – have been proven to be very active. [9]

Nowadays, the great attention is paid to the evolution of the traditional methods of generating of heat and electricity into the modern hydrogen energetics. One of the most rapidly developing areas is the search for the highly efficient catalytic systems that can generate molecular hydrogen from aqueous solutions. We suggested the use of cheap and synthetically available clathrochelates with the encapsulated cobalt(I,II and III) ions, which demonstrate unusually high thermodynamic and kinetic stability in time and may easily be functionalized using up to eight substituents. Faradaic efficiency of the electrocatalytic process 2H+/H2 strongly depends on pK of the corresponding acid as a donor of H+ ions and on the Co2+/+ redox potential because of an acid-base equilibrium with electrochemically generated encapsulated cobalt(I) ion as a base. One of the possible ways to decrease the overpotential of this reduction and, hence, to make the process more thermodynamically favorable is to vary ribbed substituents in the encapsulating macrobicyclic ligands. Using the plot of E versus Hammett spara, the potentials of the redox couples Co2+/+ for the hexachlorine-containing cobalt(II) clathrochelates were deduced and appeared to be close to that for the redox couple 2H+/H2 (HClO4). These specially designed complexes exhibit high catalytic activity in this electrocatalytic process without overpotentials. These complexes and their sulfide analogs were immobilized on an electrode surface using the substituents with terminal reactive (in particular, mercapto) groups (Scheme). Moreover, H+ ions in their acidic aqueous solutions bind to sulfur atoms of the second coordination sphere of the redoxactive encapsulated metallocenter. The presence of these activated and spatially oriented H+ ions in the vicinity of the hydrid center Co...H causes the dramatical increase in the 2H+/H2 reaction rate due to a very fast intramolecular formation of the H – H bond. Along with an immobilization of these electrocatalysts on the working electrode, this resulted in the substantial improvement of the characteristics of the electocatalytic evolution of H2 from aqueous solutions. Thus, the synthetic versatility of this family of the metal complexes provides new prospectives for fine tuning their electrochemical properties and reactivity; an approach, based on the preliminary calculations of the electrochemical characteristics of these complexes, may be used for the design of the efficient electrocatalysts for a wide range of the hydrogen-generating systems. The study was supported by RFBR (grants 10-03-00837, 10-0300613 and 12-03-00961) and RAS (program 7).

Figure 1. [FeH(PP3)]BF4 Acknowledgement. The Swiss National Science Foundation and EPFL are thanked for financial support. [1] W. Leitner Angew. Chem. Int. Ed. 1995, 34, 2207-2221. [2] P. G. Jessop; F. Joó; C-C. Tai Coord. Chem. Rev. 2004, 2425-2442. [3] R. Tanaka; M. Yamashita; K. Nozaki JACS 2009, 131, 14168-14169. [4] Y. Himeda; S. Miyazawa; T. Hirose ChemSusChem 2011, 4, 487-493. [5] C. Federsel, A. Boddien, R. Jackstell, R. Jennerjahn, P. J. Dyson, R. Scopelliti, G. Laurenczy, M. Beller; Angew. Chem. Int. Ed., 2010, 49, 9777-9780. [6] B. Loges; A. Boddien; H. Junge; M. Beller Angew. Chem. Int. Ed. 2008, 47, 3962-3965. [7] C. Fellay; P. J. Dyson; G. Laurenczy Angew. Chem. Int. Ed. 2008, 47, 3966-3969. [8] G. Papp; J. Csorba; G. Laurenczy; F. Joó Angew. Chem. Int. Ed. 2011, 50, 10433-10435. [9] A. Boddien; D. Mellmann; F. Gärtner; R. Jackstell; H. Junge; P. J. Dyson; G. Laurenczy; R. Ludwig; M. Beller Science 2011, 333, 1733-1736.

Keywords: hydrogen storage, formic acid, carbon dioxide

[1] Y.Z. Voloshin et al., Eur. J. Inorg. Chem., 2010, 5401–5415. [2] Y.Z. Voloshin et al., Chem. Commun., 2011, 47, 7737–7739. [3] Y.Z. Voloshin et al., Dalton Trans., 2012, 737 – 746. [4] Y.Z. Voloshin et al., Dalton Trans., 2012, DOI:10.1039/C2DT12513G.

Keywords: hydrogen evolution, electrocatalysts, cage complexes

MS.C2.C.07 Behavior of iridium-based molecular catalysts during water oxidation with cerium(IV) Douglas B. Grotjahn,a David C. Marelius,a Derek B. Brown,a Jessica K. Martin,a Marie-Caline Abadjian,a Hai N. Tran,a Gregory Kalyuzhny,a Kenneth S. Vecchio,b Zephen G. Specht,a aDepartment of Chemistry and Biochemistry, San Diego State University, San Diego, CA 92182-

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Microsymposia 1030 (United States). bDepartment of NanoEngineering, University of California, San Diego, La Jolla, CA 92093-0448 (United States). E-mail: [email protected] Organometallic iridium complexes have been reported as water oxidation catalysts (WOC) in the presence of ceric ammonium nitrate (CAN). One challenge for all WOC regardless of the metal used is stability. Here we provide evidence for extensive modification of many Ir-based WOC even after exposure to only 5 to 30 equiv of Ce(IV) (whereas typically 100 to 10,000 equiv are employed during WOC testing). We also show formation of iridium-rich nanoparticles (likely IrOx) even in the first 20 min of reaction, associated with a Ce matrix. A combination of UV-vis spectroscopy, scanning transmission electron microscopy (STEM), and NMR spectroscopy are used. 1H NMR spectra acquired after addition of 1 to 30 equiv of CAN show the formation of oxidized products including those from attack at a Cp* methyl group, and small organic products (formic and acetic acids). In some cases, Ir-based WOC specifically labeled with 13C atoms are shown to produce labeled species. Our results (initial report, [1]) together with others [2] suggest oxidation at iridium-bound carbons by CAN is an issue in WOC. [1] Grotjahn et al., J. Am. Chem. Soc. 2011, 133, 19024. [2] Savini, A.; Belanzoni, P.; Bellachioma, G.; Zuccaccia, C.; Zuccaccia, D.; Macchioni, A. Green Chem. 2011, 13, 3360.

Keywords: catalysis, water oxidation, iridium

MS.C2.C.08 Anaerobic oxidation of methane in mild conditions catalyzed by Au-rutin complex Alexander Shestakov, Institute of Problems of Chemical Physics, Russian Academy of Sciences, 142432, Chernogolovka, Moscow region, (Russia). E-mail: [email protected] Previously, we found that complexes of gold with a bioflavonoid catalyze the selective oxidation of methane and its homologues to alcohols by air oxygen at room temperature in water [1,2]. Rutin and quercetin can support methane oxidizing function but the rutin system is more stable and more appropriate for experimental study. According to the quantum-chemical modeling, the role of O2 in this process is the oxidation of Au(I) to Au(III) in the intermediate alkyl complexes. From this analysis it follows that O2 can be replaced by another oxidant. We found that [K3Fe(CN)6] can be used as oxidizer instead of O2. In this case the reaction becomes much faster and initial specific activity of methane oxidation is 1.2 min-1 per the entire content of Au at 25 оС. This value is close to the specific activity of the enzymatic oxidation of methane by heterodisulphide at 60 °C, 11.4 nmol/min per mg protein [3] that corresponds to 1.5 min-1, taking into account arrangement of the enzyme [4]. However methane oxidation ends after 120 min when there are enough oxidizer in the system, and the yield of methanol, 50 mole per mole of Au, does not change for 24 hours. Ethane and propane are also selectively oxidized under these conditions. But the maximal yields of ethanol (for 60 min) and isopropanol (for 15 min) well correspond to the content of the oxidizer. Two-electron oxidation of alkanes to alcohols RH + H2O + 2[Fe(CN)6]3- = ROH + 2 Н+ + 2[Fe(CN)6]3is thermodynamically possible at the experimental pH = 8. But it requires the accumulation of two oxidizing equivalents of one-electron oxidizing agent. We propose that catechol B ring in the rutin ligand of Au(I) is used for that purpose. Formation of semiquinone radical from rutin requires the standard redox potential 0.38 V at pH = 8, close to the redox potential of [Fe(CN)6]3-. This scenario is consistent with the complete loss of the catalytic activity under replacing of rutin on

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morin, which has two ortho OH groups in the ring B. However, the oxidation-reduction cycles of the ligand pose a threat to the stability of the active form of the catalyst over time. That is why only under the slow oxidation of methane there is observable disappearance of the catalytically active centers because of side oxidation processes. The proposed mechanism is supported by the results of quantumchemical modeling. Interaction of H2O with Au(I) methyl complex with quinone form of quercetin ligand lead to exothermic formation of hydroxy-methyl Au(III) complex. Acknowledgments. This work was supported by the Chemistry and Materials Science Division, Russian Academy of Sciences, under program # 1, “Theoretical and Experimental Study of the Nature of Chemical Bonding and Mechanisms of Important Chemical Reactions and Processes.” [1] L.A. Levchenko, V.G. Kartsev, A.P. Sadkov, A.F. Shestakov, A.K. Shilova, A.E. Shilov, Dokl. Chem., 2007, 412, 35-37. [2] L.A. Levchenko, N.G. Lobanova, V.M. Martynenko, A.P. Sadkov, A. F. Shestakov, A.K. Shilova, A.E. Shilov, Dokl. Chem., 2010, 430, 50-53. [3] S. Scheller, M. Goenrich, R. Boecher, R.K. Thauer, B. Jaun, Nature , 2010, 465, 606-608. [4] S. Shima, M. Krueger, T.Weinert, Demmer U., Kahnt J., R.K. Thauer, U. Ermler, Nature, 2012, 481, 98-101.

Keywords: anaerobic oxidation, methane, Au-rutin complex

MS.C2.C.09 Mechanistic insights of nitrene insertion reactions catalyzed by metal-homoscorpionate complexes W. M. C. Sameera,a A. Locati,a F. Maseras,a,b S. Castillón,c P. J. Pérez, d a Institut Català d’Investigació Química (ICIQ), 43007 Tarragona, Spain. bDepartamento de Química, Universidad Autonóma de Barcelona, 08193 Bellaterra, Spain. cDepartamento de Química Analítica y Química Orgánica, Facultad de Química, Universitat Rovira i Virgili, Tarragona, Spain. dDepartamento de Química y Ciencia de los Materiales, Universidad de Huelva, Campus de El Carmen, 21007 Huelva, Spain. E-mail: [email protected] Nitrogen atom transfer reactions constitute an important area of research in bioinorganic and organic chemistry. Transition metalmediated aziridination of olefins is a promising route for nitrogen atom transfer processes,[1,2] and undergoes highly regio- and stereoselective transformations. Pérez and co-workers has previously reported TpxM complexes (M = Ag, Cu; Tpx = homoscorpionate ligand) as effective catalysts for the aziridination of olefins using PhINTs (Ts = 4- toluenesulfonyl) as the nitrene source.[2] We present herein a detailed mechanistic study to rationalize the puzzling kinetic and selectivity issues associated with the aziridination reactions. Our experimental kinetic studies and theoretical calculations (DFT) indicated that the two-electron transfer aziridination reactions proceed through a radical mechanism. We observed the minimum energy crossing points (MECP) between singlet and triplet energy profiles at the different regions of the potential energy surfaces lead to the stereoselectivity. In case of trans, trans-2,4- hexadien-1-ol substrate, the OH- group of the substrate forms hydrogen bonding with the Ts- unit of the catalyst at long-range separations, and this ‘directing effect’ controls the regioselectivity.

Microsymposia

Keywords: aziridination reactions, density functional theory, minimum energy crossing points

MS.C2.C.10 NHC-nitrogen donor ligands in rhodium complexes for use in the Monsanto process Stefan Warsink, Andreas Roodt, Department of Chemistry, University of the Free State, Bloemfontein, South Africa. E-mail: 2011009426@ ufs4life.ac.za In our research to improve the efficiency of homogenous rhodium(I) catalysts in the carbonylation of methanol (which provides acetic acid in a multimillion tonne scale per year) through better understanding of oxidative addition and reactivity of the metal centre, we use bidentate ligands with donor sets such as O,O’, N,O and S,O.[1, 2] The use of bidentate ligands, as well as the use of strongly coordinating phosphines shows improvements in the conversion of methanol to acetic acid. We have endeavoured to combine the characteristics of these two beneficial influences into one ligand set. Because phosphines sometimes show dissociation from the metal and are liable to oxidation, we opted for the use of N-heterocyclic carbenes (NHCs).[3] These ligands are not as well-established as phosphines, but the past two decades have shown that they are versatile ligands that give stable complexes with almost any metal in the periodic table over a wide range of reaction conditions. As a secondary donor, an amide-functionality was chosen, because of its ease of synthesis and the possibility of coordinating as a neutral or as an anionic donor. A series of imidazolium salt preligands was synthesized in high yields and purities by well-described methods. The NHCs were then generated by complexation to silver(I), as this provides the intermediate AgI(NHC) complexes in high yields without the need for inert conditions. Also, these complexes act as carbene-transfer agents when combined with a suitable metal-precursor, such as [RhCl(cod)]2 (cod = 1,4-cyclooctadiene). For several of the new compounds and complexes single crystals suitable for X-ray analysis were obtained, which gave insight into the mode of coordination of the bidentate ligand and structural properties of the complexes. The reactivity of the ligands with different rhodium(I)-precursors, as well as the reactivity of the resulting complexes with different ligands and substrates was investigated in detail. Future research focuses on application of the Rh(NHC-N) complexes in the methanol carbonylation, of which the first step involving the rhodium-moiety is the oxidative addition of iodomethane.

[1] A. Roodt, G. J. J. Steyn, Res. Research Dev. Inorg. Chem., 2000, 2, 1. [2] A. Roodt, H. G. Visser, A. Brink, Cryst. Rev, 2011, 17, 241. [3] J. M. Praetorius, C. M. Crudden, Dalton Trans., 2008, 4079-4094.

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[1] P. Müller, C. Fruit, Chem. Rev. 2003, 103, 2905-2919.
 [2] D. N. Zalatan, J. D. Bois, Top. Curr. Chem. 2010, 292, 347-378. [3] J. Llaveria, Á. Beltrán, M. M. Díaz-Requejo, M. I. Matheu, S. Castillón, P. J. Pérez, Angew. Chem. 2010, 122, 7246-7249.

Keywords: Rhodium, NHC ligands, homogeneous catalysis

MS.C2.C.11 Design of Cobalt Complex Catalysts for Enantioselective Borohydride Reduction Tohru Yamada, Satoshi Kikuchi, Tatsuyuki Tsubo, Department of Chemistry, Keio University, Kohoku-ku, Yokohama, 223-8522 (Japan). E-mail: [email protected] The enantioselective reduction of carbonyl or imine derivatives is one of the most reliable methods to provide various optically active compounds. From our research group, optically active cobalt(II) complexes with a conventional reductant, sodium borohydride, [1], [2] were proposed for the catalytic enantioselective reduction of ketones as well as imines to afford the corresponding alcohols and amines in high-to-excellent yields with high enantioseletivities. Based on the theoretical and analytical studies on the cobalt-catalyzed borohydride reduction, [3] newly designed cobalt(II) complex catalysts were recently released to employ the enantioselective reduction of aliphatic ketones. By using the optically active ketoiminatocobalt(II) complex in the presence of 1,1,1-trichloroethane, several aliphatic ketones were successfully applied to the present catalytic enantioselective reduction to be converted into the corresponding secondary alcohols in good-to high yields with high enantioselectivities.[4] Based on the ESI-MS, NMR, and X-ray analyses, [5] it was confirmed that on the cobalt(III) complex 1-chlorovinyl group was attached as an axial ligand. The resulting cobalt complex could be employed as the catalyst for the enantioselective borohydride reduction. Also several times of recycle use of the present cobalt complex was examined.

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Microsymposia [1] T. Nagata, K. Yorozu, T. Yamada, T. Mukaiyama, Angew. Chem ., Int. Ed. Engl., 1995, 34, 2145-2147. [2] T. Yamada, T. Nagata, K. D. Sugi, K. Yorozu, T. Ikeno, Y. Ohtsuka, D. Miyazaki, T. Mukaiyama, Chem. Eur. J., 2003, 9, 44854509. [3] I. Iwakura, M. Hatanaka, A. Kokura, H. Teraoka, T. Ikeno, T. Nagata, T. Yamada, Chem. Asian J., 2006, 1, 656-663. [4] T. Tsubo, H.-H. Chen, M. Yokomori, K. Fukui, S. Kikuchi, T. Yamada, submitted. [5] T. Tsubo, H.-H. Chen, M. Yokomori, K. Orisaku, Y. Koide, S. Kikuchi, T. Yamada, submitted.

Keywords: cobalt, enantioselective, reduction

MS.C2.C.12 Silyl-Migration-Induced Reaction in Coordination Sphere: ROCN Bond Cleavage Hiroshi Nakazawa,a Kozo Fukumoto,b Kazumasa Hayasaka,a Masumi Itazaki,a Nobuaki Koga,c aDepartment of Chemistry, Osaka City University (Japan). bDepartment of General, Kobe City College (Japan). cGraduate School of Information Science, Nagoya University (Japan). E-mail: [email protected] C-CN bonds in organonitriles and N-CN bonds in cyanamides are very strong, so the cleavage of these bonds is known to be difficult. Recently, selective bond cleavage of these strong bonds has been achieved [1, 2], which is induced by silyl migration from a transition metal to the nitrogen of the nitrile group coordinating to a transition metal in h2 fashion. We herein report O-CN bond cleavage of cyanates (ROCN) induced by silyl group migration. The reaction of cyanates (ROCN; R = iPr, Et, Ph, p-MeC6H4) with 2 equiv of Et3SiH in toluene at 100 ºC in the presence of a catalytic amount of CpMo(CO)3Me produced Et3SiCN and ROSiEt3, showing a catalytic O-CN bond cleavage [3].

The following reaction mechanism was proposed. RICN coordinates to CpMo(CO)2(SiEt3), which is produced from the starting complex CpMo(CO)3Me, using C≡N bond in h2-fashion, followed by SiEt3 group migration from Mo to the nitrogen in ROCN to give an Mo-C-N three-membered ring. The Mo-C-N three-membered ring is converted into the Mo-C-O three-membered ring. Then, the O-CN bond is cleaved to give the Mo complex with OR and CNSiEt3 ligands.

One complex corresponding to one of the intermediates in the catalytic cycle could be isolated and characterized by X-ray analysis. [1] (a) Nakazawa, H.; Kawasaki, T.; Miyoshi, K.; Suresh, C. H.; Koga, N. Organometallics 2004, 23, 117-126. (b) Nakazawa, H.; Kamata, K.; Itazaki, M. Chem. Commun. 2005, 4004-4006. (c) Nakazawa, H.; Itazaki, M.; Kamata, K.; Ueda, K. Chem. Asian. J. 2007, 2, 882-888. [2] Fukumoto, K.; Oya, T.; Itazaki, M.; Nakazawa, H. J. Am. Chem. Soc. 2009, 131, 38-39. [3] Fukumoto, K.; Dahy, A. A.; Oya, T.; Hayasaka, K.; Itazaki, M.; Nakazawa, H. Organometallics 2012, 31, 787-790.

Keywords: cyanates, strong bond cleavage, catalytic reaction

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9 - 13 September 2012

CHAIRS Prof. ERNESTO CARMONA Prof. MARTIN ALBRECHT Prof. EDUARDO SOLA

Keynote KNnn nn = number of the Keynote Lecture Invited Inn nn= number of the Invited Lecture Contributed Cnn nn = number of the Contributed Lecture

MS.C3.KN1

MS.C3.KN3

Fe model complexes of the interstitial atom of the cofactor: A molecular spring for N2 uptake and reduction Jonas C. Peters, California Institute of Technology, Division of Chemistry and Chemical Engineering, Pasadena, California, USA. Email: [email protected]

Mesoionic Carbenes: A Versatile Platform for Transition Metal Chemistry Martin Albrecht, School of Chemistry & Chemical Biology, University College Dublin, Belfield, Dublin 4 (Ireland). E-mail: martin.albrecht@ ucd.ie

Our group has suggested previously that a hemi-labile role may be played by the interstitial light X-atom of the FeMo-cofactor, enabling a high degree of conformational and redox flexibility at a single iron N2 binding site. In this regard the central X-atom could act like a spring as the iron site coordinates various reduced nitrogenous ligands during turnover. This scenario would allow the iron center to modulate its local geometry by varying its degree of interaction with the light X-atom under crude local three-fold symmetry, possibly sampling trigonal bipyramidal, trigonal pyramidal, and/or pseudotetrahedral geometries as a function of the nature of the state of reduction of the nitrogenous ligand. Iron metalloboratranes will be discussed as inorganic models that can help us to consider this hypothesis, with the Fe-B interaction serving the function of the postulated Fe-X spring. Related model complexes recently synthesized in our labs featuring an Fe-C, instead of an Fe-B, interaction will also be discussed for comparison.

N-heterocyclic carbenes (NHCs) have had a tremendous impact on inorganic chemistry and on catalysis in particular, which has been largely associated with the unique bonding features of NHC ligands. The covalent metal-ligand bond combined with the much stronger donor ability of carbenes as compared to phosphines has provided access to a variety of new reaction pathways and increased activities in catalytic reactions. We have been interested in furthering the specific (donor) properties of the NHC ligand in order to mediate the activation of strong and typically less reactive bonds. To this end, we have been actively pursuing the development and application of mesoionic N-heterocyclic carbenes, i.e. homologues of classical NHCs that do not feature a neutral resonance structure(see Figure below). These mesoionic carbenes display an exceptionally strong donor ability when compared to other formally neutral ligands such as phosphines and classical Arduengo-type carbenes.[1] We have recently obtained evidence that the mesoionic character also entails ligand-centered reactivity, which has been exploited in bond activation catalysis.[2] Specifically, we have developed efficient catalysts based on such mesoionic carbene ligands for the oxidation of silanes, alcohols, and water.[3] We will discuss most recent developments in this area, including also mechanistic insights.

Keywords: Iron, nitrogenase, nitrogen fixation

MS.C3.KN2 Molybdenum-Catalyzed Reduction of Molecular Dinitrogen into Ammonia under Mild Reaction Conditions Yoshiaki Nishibayashi, Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 1138656, Japan. E-mail: [email protected] Synthesis of transition metal-dinitrogen complexes and stoichiometric transformation of their coordinated dinitrogen into ammonia and hydrazine have so far been well investigated toward the goal of achievement of nitrogen fixation under ambient conditions. After Schrock’s report [1], there is no example on the catalytic conversion of dinitrogen into ammonia under ambient conditions. As an extension of our study, the dimolybdenum-dinitrogen complex bearing PNP pincer ligand has been found to work as an effective catalyst for the formation of ammonia from dinitrogen, where 23 equiv of amount of ammonia are produced based on the catalyst (12 equiv of ammonia are produced based on the molybdenum atom of the catalyst) [2]. This is another successful example of the catalytic and direct conversion of dinitrogen into ammonia under ambient reaction conditions [3].

[1] O. Schuster, L. Yang, H. G. Raubenheimer, M. Albrecht, Chem. Rev. 2009, 109, 3445–3478; M. Albrecht, Chem. Commun. 2008, 3601–3610; M. Melaimi, M. Soleilhavoup, G. Bertrand, Angew. Chem. Int. Ed. 2010, 49, 8810–8849. [2] A. Krüger, L. J. L. Häller, H. Müller-Bunz, O. Serada, A. Neels, S. A. Macgregor, M. Albrecht, Dalton Trans. 2011, 40, 9911–9920; A. Krüger, M. Albrecht, Chem. Eur. J. 2012, 18, 652–658; A. Krüger, M. Albrecht, Aust. J. Chem. 2011, 64, 1113–1117. [3] R. Lalrempuia, N. D. McDaniel, H. MüllerBunz, S. Bernhard, M. Albrecht, Angew. Chem. Int. Ed. 2010, 49, 9765–9768; A. Prades, E. Peris, M. Albrecht, Organometallics, 2011, 30, 1162–1167.

Keywords: N-heterocyclic carbene, oxidation, ligand cooperativity

MS.C3.I1

[1] D. V. Yandulov and R. R. Schrock, Science 301, 76-78 (2003). [2] K. Arashiba, Y. Miyake, and Y. Nishibayashi
, Nature Chemistry, 3, 120-125 (2011). [3] R. R. Schrock, Nature Chemistry, 3, 95-96 (2011).

Synthesis and Properties of Superazaporphyrins and Novel Subphthalocyanines Nagao Kobayashi,a Soji Shimizu,a Taniyuki Furuyama,a Akito Miura,a Samson Khene,b Tebello Nyokong,b Yosuke Ogura,a Tatsuya Otaki,a Hua Zhu,a Shota Nakano,a Takahisa Hosoya,a aDepartment of Chemistry, Graduate school of Science, Tohoku University, Sendai, (Japan). bDepartment of Chemistry, Rhodes university, Grahamstown 6140, South Africa. E-mail: [email protected]

Keywords: dinitrogen, ammonia, molybdenum

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Microsymposia

Microsymposia Pentapyrrolic azamacrocycles containing UO2 as the central core (i.e. superazaporphyrins, SAzPs) have been synthesized from the pentacyclization reaction of a 3,4-bis(phenyl)pyrroline-2,5-diimine derivative using UO2(OAc)2 as a template, and their spectro-scopic and electrochemical properties examined.[1] Their pi structure is not flat, but severely distorted in the solid state, and they show Q bands at around 870-890 nm. They are stable since both the LUMOs and HOMOs are stabilized compared to normal phthalocyanines (Pcs) and naphthalocyanines (Ncs). Various kinds of subPcs or subNcs containing reduced pyrrole rings, pyrene, and 1,8- or 1,2-naphthalene units have been synthesized and characterized. A reduced pyrrole-ring-containing subPc (i.e. subazachlorin) showed a significantly split Q band at 632 and 464 nm (splitting E = ca. 5730 kcm-1), while even the Soret band split at 308 and 269 nm (splitting E = ca. 4700 kcm-1) due to the lowering of the molecular symmetry.[2] The corresponding subaza-porphyrin also showed a split Q band at 561 and 383 nm (splitting E = ca. 8010 kcm-1) due to less pi-conjugation. The concave conjugation of pyrenefused subPc enhanced its co-crystallization with C60 molecules. [3] A low-symmetry subPc consisting of two di-substituted benzene and a 1,8-naphto unit was synthesized by mixed condensation of 4,5-disubstituted phthalonitrile and 1,8-dicyanonaphthalene in the presence of BCl3.[4] The Q band peaks of this compound appeared in the 600-708 nm region, compared with 573 nm for a subPc consisting of three phthalonitrile units. A subNc consisting of 1,2-naphthalene units was synthesized from 1,2-dicyanonaphthalene also using BCl3 as a template, and its C1 and C3 diastereomers and enantiomers were separated.[5] The chirality of this molecule, including the CD sign and intensities, was discussed with reference to enantiomerically-pure molecules whose absolute structures had been elucidated by singlecrystal X-ray diffraction analysis. Viewing from the axial ligand side of B, the compounds with a clockwise arrangement of benzene rings exhibited a negative CD band in the Q band region, while, inversely, those with an anti-clockwise arrangement showed positive CD bands. [1] Yosuke Ogura, Bachelor Thesis, Tohoku University, 2011. [2] S. Shimizu, T. Otaki, et al, Chem. Commun. 2012, 48, 4100-4102. [3] S. Shimizu, S. Nakano et al, Chem. Commun. 2011, 47, 316-318. [4] H. Zhu, S. Shimizu, N. Kobayashi, Angew. Chem. Int. Ed. 2010, 49, 8000-8003. [5] S. Shimizu, N. Kobayashi et al, J. Am. Chem. Soc., 2011, 133, 17322.

Keywords: phthalocyanine, subphthalocyanine, superazaporphyrin

MS.C3.I2 Iridium Complexes as Efficient Catalysts for Water Oxidation Alceo Macchioni, Arianna Savini, Gianfranco Bellachioma, Luca Rocchigiani, Cristiano Zuccaccia, Department of Chemistry, University of Perugia, Perugia, (Italy). E-mail: [email protected] The discovery of new complexes that efficiently catalyze water oxidation to molecular oxygen is extremely important in the framework of artificial photosynthesis and electrochemical split of water [1-4]. Recently, iridium organometallic complexes emerged as active (pre)catalysts for water oxidation driven by Ce(IV) [5]. Most of them bear the Cp*Ir moiety (Cp*=pentamethyl-cyclopentadienyl-ligand) [6-10]. The presence of an Ir–C– bond in those (pre)catalysts is, on one hand, beneficial in terms of high electron-density donation to the metal center that makes it more prone to be oxidized. On the other hand, the Ir–C– bond could be the Achilles’ heel of the catalyst where the oxidative degradation can initiate, as indicated by recent NMR studies [11-13]. In this contribution, we compare the activity of iridium (pre) catalysts for water oxidation based on their kinetics (order in catalyst and cerium) more than on TOF and TON values that are strongly

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dependent on the experimental conditions under which catalytic experiments are performed. We also report the results of in situ NMR studies shedding some light on the degradation pathways of selected archetypal catalysts. Finally, we show that the readily available and highly water-soluble [IrCl(Hedta)]Na [14] complex is an efficient (pre) catalyst for water oxidation to molecular oxygen having performance comparable with those of the best catalysts reported so far (TOF = 6.8 min-1 and TON > 12000) [15].

[1] V. Balzani, A. Credi, M. Venturi, ChemSusChem, 2008, 1, 26-58. [2] D. G. Nocera, ChemSusChem, 2009, 2, 387-390. [3] M. Grätzel, Acc. Chem. Res., 1981, 14, 376-384. [4] T. J. Meyer, Acc. Chem. Res., 1989, 22, 163-170. [5] N. D. McDaniel, F. J. Coughlin, L. L. Tinker, S. Bernhard, J. Am. Chem. Soc., 2008, 130, 210-217. [6] J. F. Hull, D. Balcells, J. D. Blakemore, C. D. Incarvito, O. Eisenstein, G. W. Brudvig, R. H. Crabtree, J. Am. Chem. Soc., 2009, 131, 8730-8731. J. D. Blakemore, N. D. Schley, D. Balcells, J. F. Hull, G. W. Olack, C. D. Incarvito, O. Eisenstein, G. W. Brudvig, R. H. Crabtree, J. Am. Chem. Soc., 2010, 132, 16017-16029. [7] A. Savini, G. Bellachioma, G. Ciancaleoni, C. Zuccaccia, D. Zuccaccia, A. Macchioni, Chem. Commun., 2010, 46, 9218-9219. [8] R. Lalrempuia, N. D. McDaniel, H. Mueller-Bunz, S. Bernhard, M. Albrecht, Angew. Chem., Int. Ed., 2010, 49, 9765-9768. [9] D. G. H. Hetterscheid, J. N. H. Reek, Chem. Commun., 2011, 47, 2712-2714. [10] D. Hong, M. Murakami, Y. Yamada, S. Fukuzumi, Energy Environ. Sci., 2012, 5, 5708-5716. [11] A. Savini, P. Belanzoni, G. Bellachioma, C. Zuccaccia, D. Zuccaccia, A. Macchioni, Green Chem., 2011, 13, 3360-3374. [12] D. B. Grotjahn, D. B. Brown, J. K. Martin, D. C. Marelius, M.-. Abadjian, H. N. Tran, G. Kalyuzhny, K. S. Vecchio, Z. G. Specht, S. A. Cortes-Llamas, V. MirandaSoto, C. van Niekerk, C. E. Moore, A. L. Rheingold, J. Am. Chem. Soc., 2011, 133, 19024-19027. [13] C. Zuccaccia, G. Bellachioma, S. Bolaño, L. Rocchigiani, A. Savini, A. Macchioni, Eur. J. Inorg. Chem., 2012, 1462-1468. [14] M. Saito, T. Uehiro, Y. Yoshino, Bull. Chem. Soc. Jpn., 1980, 53, 35313536. [15] A. Savini, G. Bellachioma, S. Bolaño, L. Rocchigiani, C. Zuccaccia, D. Zuccaccia, A. Macchioni submitted for publication.

Keywords: iridium complexes, water oxidation, water splitting

MS.C3.I3 Reversible Carbene Insertions into the Ru−Si Bond of Ru(k-P,P,Si) Pincer Complexes Eduardo Sola, María José Bernal, Marta Martín, Instituto de Síntesis Química y Catálisis Homogénea, CSIC-Universidad de Zaragoza, Zaragoza (Spain). E-mail: [email protected] The trans-labilizing capability of the sp3 silyl groups may favor distinctive coordination geometries in unsaturated complexes of d6 metal centers, as has recently been discussed for Ir(III) derivatives with k-P,P,Si pincer ligands. [1] This is also the case for Ru(II) (k-P,P,Si) analogues of the Grubbs catalyst: complexes that can coordinate incoming molecules in positions cis to their carbene ligand. Such a characteristic might be advantageous in the context of olefin metathesis catalysis, since it could afford new catalysts that - in contrast to all generations of Grubbs catalysts - do not need to preactivate via dissociation of an ancillary ligand. [2] Unfortunately, this possibility fails to be materialized given that coordination of ligands (olefins included) firstly causes an insertion of the carbene into the Ru−Si bond. Despite its inconvenience for olefin metathesis, this latter reaction can promote new C−H activation and C−C forming reactions, as will be illustrated and discussed for alkynes as incoming reagents.

[1] E. Sola, A. García-Camprubí, J. L. Andrés, M. Martín, P. Plou, J. Am. Chem. Soc., 2010, 132, 9111-9121. [2] R. H. Grubbs, Tetrahedron, 2004, 60, 71177140.

Keywords: Pincer Complexes, Silyl Complexes, C-C Bond Formation

Microsymposia MS.C3.I4

types of CC agostic interactions, one with Li with an electrostatic character, one with Y with a more covalent character.[5]

Reactivity of (Salen)ruthenium(VI) Nitrido Complexes T. C. Lau, Wai-Lun Man, William W. Y. Lam, Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong, P. R. China. E-mail: [email protected]

[1] W. L. Man, T. M. Tang, T. W. Wong, T. C. Lau, S. M. Peng, W. T. Wong, J. Am. Chem. Soc., 2004, 126, 478–479. [2] W. L. Man, W. W. Y. Lam, S. M. Yiu, T. C. Lau, S. M. Peng, J. Am. Chem. Soc., 2004, 126, 15336–15337. [3] H. K. Kwong, W. L. Man, J. Xiang, W. T. Wong, T. C. Lau, Inorg. Chem. 2009, 48, 3080–3086. [4] W. L. Man, W. W. Y. Lam, H. K. Kwong, S. M. Peng, W. T. Wong, T. C. Lau, Inorg. Chem. 2010, 49, 73–81.

[1] Selected examples: (a) S. K. Brayshaw, E. L. Sceats, J. C. Green, A. S. Weller, Proc. Natl. Acad. Sci. U.S.A. 2007, 104, 6921; (b) S. Scheins, M. Messerschmidt, M. Gembicky, M. Pitak, A. Volkov, P. Coppens, B. G. Harvey, G. C. Turpin, A. M. Arif, R. D. Ernst, J. Am. Chem. Soc. 2009, 131, 6154; (c) M. Gandelman, L. Konstantinovski, H. Rozenberg, D. Milstein, Chem. Eur. J. 2003, 9, 2595; (d) B. Goldfuss, P. v. R. Schleyer, F. Hampel, J. Am. Chem. Soc. 1996, 118, 12183 [2] P. E. Romero, W. E. Piers, J. Am. Chem. Soc. 2007, 129, 1698. [3] A. B. Chaplin, J. C. Green, A. S. Weller, J. Am. Chem. Soc. 2011, 133, 13162. [4] (a) C. Boulho, P. Oulié, L. Vendier, M. Etienne, V. Pimienta, A. Locati, F. Bessac, F. Maseras, D. A. Pantazis, J. E. McGrady, J. Am. Chem. Soc. 2010, 132, 14239; (b) C. Boulho, T. Keys, Y. Coppel, L. Vendier, M. Etienne, A. Locati, F. Bessac, F. Maseras, D. A. Pantazis, J. E. McGrady, Organometallics 2009, 28, 940; (c) J. Jaffart, M. L. Cole, M. Etienne, M. Reinhold, J. E. McGrady, F. Maseras, Dalton Trans. 2003, 4057. [5] Y. Escudié, C. Dinoi, O. Allen, L. Vendier, M. Etienne, Angew. Chem. Int. Ed. 2012, 51, 2461.

Keywords: nitrido, ruthenium, salen

Keywords: agostic interactions, CH activation, DFT calculations

MS.C3.I5

MS.C3.C.01

On the nature and consequences of CC agostic interactions Michel Etienne,a,b. aCNRS; LCC (Laboratoire de Chimie de Coordination); 205 route de Narbonne, BP 44099, F-31077 Toulouse, France, b Université de Toulouse; UPS, INPT; LCC; F-31077 Toulouse, France. E-mail: [email protected]

Multi-Electron Redox Reactions in f-Elements Schiff Base Complexes Clément Camp, Valentin Guidal, Jacques Pécaut and Marinella Mazzantia, aLaboratoire de Reconnaissance Ionique et Chimie de Coordination of Inorganic Chemistry, SCIB, UMR-E CEA/UJFGrenoble 1, CEA-Grenoble, INAC, 17 rue des Martyrs, 38054 Grenoble (France). E-mail: [email protected]

Despite their relative scarcity, agostic complexes where a CC,[1] rather than a CH, bond interacts with a main group or transition metal have been attracting strong attention recently. This stems from their involvement in metallacyclobutanes that are intermediates in alkene metathesis reactions,[2] and also in their ability to model CC s-complexes and CC bond cleavage.[3] In this talk, I will summarize some of our results highlighting structural (solid state and solution) and reactivity data as well as the importance of computational modelling. Two types of a-CC agostic complexes based on the cyclopropyl ligand will be considered: (i) hydrotris(pyrazolyl)borate niobium complexes [TpMe2NbX(c-C3H5) (MeCCMe)] (X = Cl, Me, etc.) from which hydrocarbon CH bond activation has been developed,[4] and (ii) an heterobimetallic lithium yttrium complex [(h5-C5Me5)2Y(m-c-C3H5)2Li(thf)] that exhibits two

Multi-electron redox reactions play a key role in many biological and synthetic catalytic processes. Multiple-electron transfer reactions can be achieved from the association of redox-active metal centers and polydentate unsaturated ligands which can store electrons in a reduced form. A particular high current interest arises from the ability of complexes of low-valent f-elements to promote unusual reductive chemistry through unusual reaction pathways, including attractive examples of CO, CO2 and N2 activation. This renders particularly attractive the development of f-elements complexes capable of performing multi-electron reductions. Accordingly, we investigated the association of low-valent uranium and lanthanides (Eu, Nd, Tb, Yb) with non-innocent highly

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Metal nitrides (M≡N) are believed to be one of the key intermediates in biological and chemical nitrogen fixation. They also have rich redox and catalytic properties. Recent work in our laboratory shows that (salen)ruthenium(VI) nitrido species [Ru(N) L]+ possess rich electrophilic properties.[1–4] For example, they react with a variety of nucleophiles including amines, olefins, phosphines, thiols and isocyanides to produce ruthenium(IV) hydrazido, aziridido, phosphiniminato, sulfilamido and ruthenium(III) carbodiimido complexes, respectively. In the presence of pyridine, [Ru(N)L]+ is also able to abstract C-H bonds from alkanes.

Microsymposia p-delocalized Schiff bases ligands. This led to the isolation of electronrich complexes [1], which are stabilized by storing electrons on the ligands through the formation of C-C bonds. Interestingly, these C-C bonds can be cleaved by oxidizing agents and the electrons released to participate in multi-electron redox reactions, thus providing a unique electron reservoir. Moreover, they offer a new entry to the rational design of homo- and hetero-bimetallic entities which combines multiple redox-active centers on the same molecule. The synthesis, structural characterization, electrochemistry, reactivity and magnetic studies of these new electron-rich f-elements complexes will be presented.

[1] C. Camp, V. Mougel, P. Horeglad, J. Pécaut and M. Mazzanti, J. Am. Chem. Soc., 2010, 132(49), 17374-17377.

Keywords: f-elements, Schiff bases, multi-electron transfer

Int. Ed. 2011, 50, 1711-1715. [5] F. F. Pfaff, F. Heims, S. Kundu , S. Mebs, K. Ray Chem. Commun., 2012, 48, 3730-3732.

Keywords: Metal-oxo units, C-H activation, Oxo-transfer reactions

MS.C3.C.03 Binuclear Complexes of the Siamese Twin Pophyrin Franc Meyer,a* Lina K. Frensch,a Christian Brückner,b Serhiy Demeshko,a Sebastian Dechert,a Michael John,a aInstitute of Inorganic Chemistry, Georg-August-University, Tammannstrasse 4, D-37077 Göttingen (Germany). bDepartment of Chemistry, University of Connecticut, Storrs, CT 06269-3060 (USA). E-mail: franc.meyer@ chemie.uni-goettingen.de The Siamese Twin Porphyrin is a novel type of expanded porphyrin that consists of four pyrrole and two pyrazole units.[1] It can be viewed as the fusion of two {N4} porphyrin-like coordination sites, and hence it can bind two metals in close proximity within the highly preorganized scaffold. The Siamese Twin Porphyrin and its dinuclear metal complexes feature various interesting properties that will be presented, including: (i) a complex protonation sequence of the two {N4} porphyrin-like sites (ii) persistent helical chirality that arises from the severe twisting of the pyrazole-expanded core (iii) unusual ferromagnetic coupling between the metal ions in the binuclear complexes (iv) non-innocence of the ligand scaffold that gives rise to a complex sequence of redox events, both metal- and ligand-centered.

MS.C3.C.02 High-valent terminal oxo and imido complexes of late transition metals Kallol Ray, Subrata Kundu, Florian Pfaff, Florian Heims, Department of Chemistry, Humboldt University, Berlin (Germany). E-mail: kallol. [email protected] Although terminal CoIV-O, NiIII-O and CuIII-O intermediates have been implicated as active intermediates in a number of important chemical transformations, no spectroscopic evidences for the species are available, leaving the pathway uncertain.[1,2] Evidences of the presence of terminal M-O units (M = Cu(III), Ni(III) or Co(IV)) are to date limited to mass spectrometric studies in the gas phase.[2b] Theory suggests that they should be powerful oxidants,[2a,2b] perhaps even more reactive than the related [FeIV=O]2+ units that have been extensively studied.[3] In this presentation, we will summarize some of our recent efforts to stabilize the elusive metal-oxo and isoelectronic metal-imido units of Cu(III), Co(IV)[4] and Ni(III)[5]) in solution phase at low temperatures. The high-valent metal-oxo or metal-imido assignments are made on the basis of a variety of spectrscopic methods. The reactivity of the intermediates in hydrogen atom abstraction and oxo transfer reactions are also discussed. [1] a) J.W. Egan, Jr., B. S. Haggerty, A. L. Rheingold, S. C. Sendlinger, K. H. Theopold, J. Am. Chem. Soc. 1990, 112, 2445-2446; b) O. M. Reinaud, K. H. Theopold, J. Am. Chem. Soc. 1994, 116, 6979-6980; c) W. Nam, I. Kim, Y. Kim, C. Kim, Chem. Commun. 2001, 14, 1262-1263. d) C. J. Chang, Z.-H. Loh, C. Shi, F. C. Anson, D. G. Nocera, J. Am. Chem. Soc. 2004, 126, 10013-10020. [2] a) A. W. Pierpont, T. R. Cundari, Inorg. Chem. 2010, 49, 2038–2046. b) D. Schröder, H. Schwarz, Angew. Chem. Int. Ed. 1995, 34, 1973-1995; c) S. Yao, E. Bill, C. Milsman, K. Wieghardt, M. Driess, Angew. Chem., Int. Ed. 2008, 47, 7110–7113. [3] J. Hohenberger, K. Ray, K. Meyer, Nat. Commun. 2012, 3:720 doi: 10.1038/ncomms1718. [4] F. F. Pfaff, S. Kundu, M. Risch, F. Heims, I. P. Ray, P. Haack, R. Metzinger, E. Bill, H. Dau, P. Comba, K. Ray. Angew. Chem.

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[1] L. K. Frensch, K. Pröpper, M. John, S. Demeshko, C. Brückner, F. Meyer, Angew. Chem. Int. Ed. 2011, 50, 1420-1424.

Keywords: Expanded Electronic Structure

Porphyrins,

Binuclear

Complexes,

MS.C3.C.04 Solution-State Self-Assembly of One-Dimensional Metal Wires Michael G. Campbell, Tobias Ritter, Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts (USA). E-mail: [email protected] One-dimensional metal wires organized by metal–metal bonding have been targets of synthesis for more than a century due to the interesting properties they have been predicted to display, such as roomtemperature superconductivity. [1-2] However, there are few welldefined examples of metal–metal bonded 1-D chains, and therefore a systematic study of conductivity with variation of molecular properties has not previously been reported. Our group has previously reported chemical reactivity from dipalladium(III) complexes featuring metal–metal bonding, and we have recently extended our work in metal–metal bonded complexes

Microsymposia many limitations of single-metal lithium reagents. This presentation will outline our latest contributions to this emerging area. We demonstrate how such co-operative (synergic) effects between these distinct metals in mixed-metal ate formulations can produce useful and surprising metallation reactions that cannot be replicated by the single metal complexes on their own. Key examples focusing on newly developed alkali metal dialkyl-diamidoaluminate reagents “M(TMP)2Al(iBu)2” (M is Li or K; TMP is 2,2,6,6-tetramethylpiperidide) will be discussed.[5] If, as is common practice, such metallation reactions are performed in situ, the synthetic chemist can be blind to the nature of the heterobimetallic reagent as well as to that of the metallated substrate intermediates. Here we attempt to open this black box of mixedmetal TMP metallating reagents by isolating and studying both the metallating reagents and the metallo intermediates formed on reaction with organic substrates.[6] Germane to the theme of the conference, this study reveals a remarkable hidden coordination chemistry manifested in novel metallocyclic ring motifs. A spectacular example of how an unwanted complication to a synthetic chemist, namely an unselective dimetallation of thiophene instead of a selective monometallation of this important heterocycle, can lead to a new type of zincacycle, which can be regarded as a polarity-reversed analogue of the rare zinc [16] crown-4 metallocycle. [1] A. R. Kennedy, J. Klett, R. E. Mulvey, D. S. Wright, Science, 2009, 326, 706-708. [2] S. H. Wunderlich, C. J. Rohbogner, A. Unsinn, P. Knochel, Org. Process Res.& Dev., 2010, 14, 339-345. [3] Y. Kondo, M. Uchiyama et al., J. Am. Chem. Soc., 2007, 129, 12734-12738. [4] R. E. Mulvey, Acc. Chem. Res., 2009, 42, 743-755. [5] B. Conway, E. Crosbie, A. R. Kennedy, R. E. Mulvey, S D. Robertson, Chem. Commun., 2012, 48, DOI: 10.1039/C2CC30795B. [6] J. A. Garden, A. R. Kennedy, R. E. Mulvey, S, D. Robertson, Chem. Commun., 2012, 48, DOI: 10.1039/C2CC31793A.

Keywords: ate compounds, metallation, metallocycles

MS.C3.C.06 Figure 1. Synthesis and x-ray crystal structure of a 1-D palladium(III) wire with metal–metal bonds [1] Bera, J. K. & Dunbar, K. R. Angew. Chem. Int. Ed. 2002, 41, 4453. [2] Little, W. Phys. Rev. 1964, 134, 1416. [3] Powers, D. C. & Ritter, T. Nature Chem. 1, 302 (2009). [4] Campbell, M. G., et al. Nature Chem. 2011, 3, 949.

Keywords: palladium, coordination polymers, molecular wires

MS.C3.C.05 FascinATES: Synthetic and Structural Consequences of Bimetallic Co-operation Robert E. Mulvey, WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow (Scotland, UK). E-mail: [email protected] Exploiting and understanding co-operative effects between different components in chemical reactions has long been of interest to chemists. This topic is presently making a substantial impact in synthetic chemistry especially with regard to fundamentally important reactions such as metallation and metal-halogen exchange, both of which are prominent in pharmaceutical and fine chemical manufacture. Lithium amides and lithium alkyls have generally been the reagents of choice for such applications but their dominance is now being challenged by new bimetallic systems [1]-[4] which can overcome

Connecting the Molecular and Solid State Chemistry of Technetium Alfred P. Sattelberger,a Frederic Poineau,b Erik V. Johnstone,b William Kerlin,b Paul M. Forster,b Kenneth R. Czerwinski,b aEnergy Engineering and Systems Analysis Directorate, Argonne National Laboratory, Argonne,(USA). bDepartment of Chemistry, University of Nevada Las Vegas, Las Vegas, (USA). E-mail: [email protected] At a fundamental level, the chemistry of an element is defined by its binary compounds with other elements. Almost every element in the periodic table has well-defined halide chemistry. One exception to this generalization is technetium. Prior to 2008, only 3 binary halides of this radioelement had been reported, viz., TcF6, TcF5 and TcCl4, and these compounds were prepared almost 60 years ago from the reactions of the metal with F2 or Cl2. Since 2008, we have synthesized and characterized an additional 6 binary halides, including two polymorphs of TcCl3, TcCl2, TcBr4, TcBr3 and TcBr2. The new halides fall into one of three categories: (1) those that have molybdenum and ruthenium analogs, (2) those that have rhenium analogs, and (3) those for which no analogs with neighboring elements exist. In this talk, we will describe several synthetic routes to the new halides and their relationship to molecular technetium systems where such relationships exist. We will also describe their solid-state structures, their individual thermal stabilities, and their aqueous and non-aqueous chemistry. The synthesis of these new halide compounds opens up new possibilities for exploring the synthetic and mechanistic chemistry of low-valent technetium. Keywords: Technetium, Binary halides, Structure

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to synthesize a new class of 1-D metal wires. [3-4] In this work, we describe a high-yielding solution-phase synthesis of 1-D palladium wires supported by metal–metal bonding, and their thin-film conductive properties. The 1-D wires are infinite in the solid state, and extended chain structures up to 750 nm long are maintained in solution, allowing for solution processing. By varying molecular properties such as palladium oxidation state and counteranion, different supramolecular architectures can be accessed. Thin films cast from solutions of 1-D palladium wires display divergent conductive properties based on palladium oxidation state, and an unprecedented metal-to-insulator transition is observed for films composed of palladium(2.5)-based wires. These results suggest that molecular control elements may ultimately be used to control the structures and conductive properties of self-assembled 1-D metal wires.

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MS.C3.C.08

Unusual activations of oxygen molecules by early transition metal chlorides Fabio Marchetti,a Mohammad Hayatifar,a Guido Pampaloni,a Stefano Zacchini,b aDipartimento di Chimica e Chimica Industriale, University of Pisa, Pisa (Italy). bDipartimento di Chimica Fisica e Inorganica, University of Bologna, Bologna (I). E-mail: [email protected]

Breakthroughs in Oxygenation and Hydrolysis of Zinc Alkyls Janusz Lewiński,a,b aInstitute of Physical Chemistry, Polish Academy of Sciences, Warsaw. bDepartment of Chemistry, Warsaw University of Technology, Warsaw (Poland). E-mail: [email protected]

NbCl5, MoCl5 and WCl6 are commercial non expensive compounds, which have found application in material and synthetic chemistry. Nonetheless the knowledge about the direct interaction of these transition metal halides with stoichiometric amounts of organic molecules is far from being well understood. Recently, our systematic study on the chemistry of MX5 (M = Nb, Ta; X = halide) with oxygen donors has provided evidence of interesting and unusual features. [1] Here we report the distinct activation routes followed by a series of simple carbonyl-containing molecules when contacted with the cited chlorides. For instance, natural aminoacids are deoxygenated by MoCl5, whereas rare decarboxylation to iminium may occur with NbCl5 (Figure 1). Furthermore WCl6 acts as efficient chlorinating agent towards ketones and amides. In particular, the reaction with acetanilide proceeds with C-N coupling and yields acylamidinium salt in mild conditions (Figure 2).

It is over 150 years since the interaction of zinc alkyls with O2 and H2O has been of a continuous interest, however significant uncertainties in the composition of the products have persisted. Continually, it is a big challenge to bring the hydrolysis reactions under control to favor the more rapid design and implementation of O2- and H2O-based reaction systems. We will provide a new look at these old problems, and in the second part , the lecture will focus on the preparative exploitation of the oxygenation and hydrolysis reactions in materials chemistry. Using various well-defined zinc alkyls, we have succeeded in the isolation and structure characterization of a series of the oxygenation reaction intermediates and products, such as peroxo, oxo, alkylperoxo, and even carboxylate complexes. The achieved fundamental knowledge has facilitated efforts to elucidate a new oxygenation mechanism, which is significantly different from the commonly accepted radicalchain mechanism. [1] We will also show structure characterization and thermal stability of the unprecedented example of alkylzinc hydroxide, i.e. hexameric [(RZnOH)6] cluster,[2] as well as its application as predesigned precursor of ZnO nanoparticles. [1] J. Lewiński, W. Śliwiński, M. Dranka, I. Justyniak, J. Lipkowski, Angew. Chem. Int. Ed., 2006, 45, 4826-4829; J. Lewiński, K. Suwała, M. Kubisiak, Z. Ochal, I. Justyniak, J. Lipkowski, Angew. Chem. Int. Ed.,, 2008, 47, 78887891; K. Zelga, I. Justyniak, M. Kubisiak, Z. Kaszkur, J. Lewiński, Angew. Chem. Int. Ed., 2012, submitted. [2] W. Bury, E. Krajewska, M. Dutkiewicz, K. Sokołowski, I. Justyniak, Z. Kaszkur, K. J. Kurzydłowski, T. Płociński, J. Lewiński, Chem. Commun., 2011, 47, 5467-5469.

Keywords: zinc alkyls, dioxygen, water

MS.C3.C.09 Figure 1

Figure 2 [1] (a) F. Marchetti, G. Pampaloni, Chem. Commun., 2012, 48, 635-653. (b) F. Marchetti, G. Pampaloni, C. Pinzino, S. Zacchini, Angew. Chem. Int. Ed. 2010, 49, 5268-5272.

Keywords: Transition metal halides; coordination chemistry; C-O activation

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Reduction of O2 to H2O with a Dinuclear Manganese(II)-Thiolate Complex Marcello Gennari,a Jacques Pécaut,b Marie-Noëlle Collomb,a Carole Duboc,a aDépartement de Chimie Moléculaire, Université Joseph Fourier, Grenoble (France). bLaboratoire de Reconnaissance Ionique et Chimie de Coordination, CEA, Grenoble (France). E-mail: marcello. [email protected] The highly exergonic 4-electron reduction of dioxygen to water in acidic medium (E0 = 1.23 V vs NHE) plays an essential role in both biology and energy production. In the final stages of aerobic respiration, the cytochrome c oxidase catalyzes this conversion, coupled with the production of ATP [1]. In addition, dioxygen is catalytically reduced to water in H2/O2 fuel cells to produce electrical work [2]. In this context, an important challenge is to replace the expensive Pt-containing catalysts that are currently used to promote this cathodic process with cheaper and more abundant metals. In the particular case of manganese, only one mononuclear Mn complex is known to catalyze dioxygen reduction to water, in presence of a chemical reducing agent [3]. Here, we report a Mn complex that activates O2, reducing it directly to H2O, in absence of external reducing agents. This study represents a rare example of mechanistic investigation in the field of O2 reduction. We prepared the dimeric Mn(II)-thiolate complex 1 (see figure) that promptly reacts with O2 in acetonitrile solution, yielding a dinuclear hydroxo-bridged Mn(III) species (3), via a (hydro)peroxo intermediate

Microsymposia hydroxido-complexes [PtCl6‑n(OH)n]- (n = 0-5) in alkaline solution are only resolved as a function of the various isotopologues. The isotope effects are ascribed to the extreme sensitivity of the 195Pt NMR shileding to differences in the M_35Cl/37Cl and M_16O/18O bond displacements at the 10-5Å level, as recently confirmed by DFT calculations[3].

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(2). Complex 3 can be protonated by 2,6-lutidinium tetrafluoroborate ([HLut]BF4), producing water and a Mn(III)-thiolate dimer (4). In the presence of [HLut]BF4, the initial complex 1 can be regenerated by electrochemical reduction (-0.5 V vs Ag/Ag+) of 4. The global reaction is: O2 + 4[HLut]+ + 4 e- → 2H2O + 4Lut. However, because the addition of the reagents (O2 and protons) and the application of the electrical potential are sequential events, the process is not catalytic. The reaction pathway (see figure) is proposed on the basis of different experimental evidences (X-ray structures, UV-vis and ESI-MS spectra, cyclic voltammetry). Electrocatalytic studies are in progress.

Pt NMR signal of cis-[Pt35/37Cl4(H216/18O)2]

195

[1] S. Ferguson-Miller, G. T. Babcock, Chem. Rev., 1996, 96, 2889-2908. [2] A. A. Gewirth, M. S. Thorum, Inorg. Chem., 2010, 49, 3557-3566. [3] R. L. Shook, S. M. Peterson, J. Greaves, C. Moore, A. L. Rheingold, A. S. Borovik, J. Am. Chem. Soc., 2011, 133, 5810-5817.

Similar 35Cl/37Cl effects are visible in the 103Rh NMR spectra of [RhCl6‑n(H2O)n](3-n)- (n = 3-6) complexes[4], allowing for the unambiguous assignment of these species in solution, as well as constructing an accurate ‘species distribution’ diagram in HCl, something of significance for efficient separation and recovery of this valuable precious metal.

Keywords: dioxygen reduction, manganese, thiolate

MS.C3.C.10 Cl and 16/18O isotope resolved 195Pt and 103Rh NMR as unique fingerprints of PtIV and RhIII complex anions Klaus R Koch, Department of Chemistry and Polymer Science, Stellenbosch University, P. Bag X1, Matieland, South Africa. E-mail: [email protected] 35/37

High resolution 195Pt and 103Rh NMR (at high magnetic fields, 14.09 T) is a powerful tool with which to understand the chemistry and speciation of thier complexes in aqueous solutions relevant to process solutions. The NMR nuclear shielding of PtIV and RhIII complexes is extremely sensitive to several factors, inter alia temperature, solvent composition, speciation and the isotopic distribution of coordinated ligands[1]. To date, the potential of isotope effects as a structural tool has largely been ignored. 195 Pt NMR resonance shapes of the complexes [PtCl6‑n(H2O) (4-2+n)] (n = 0-5) are well resolved into the various isotopomers for n each possible isotopologue, resulting from the 35Cl/37Cl (and 16O/18O) isotope effect on the 195Pt resonances. Such (mass) resolved 195Pt NMR resonances constitute unique ‘fingerprints’ for the unambiguously identifcation of such complexes including the stereoisomers in solution[2]. Interestigly, the 195Pt NMR resonances of the Pt(IV)

103

Rh NMR signal of [Pt35/37Cl5(H2O)]2-

[1] K R Koch, M R Burger, J Kramer and A N Westra, Dalton Trans., 2006, 3277-3284. [2] W J. Gerber, P Murray and K R Koch, Dalton Trans. 2008, 4113-4117. [3] J C. Davis, M Bühl,and K R. Koch, J Chem. Theory. Comput., 2012 dx.doi.org/10.1021/ct300105q. [4] T E Geswindt, W J Gerber, D J Brand, K R Koch, Analytica Chimica Acta, 2012, doi:10.1016/j.aca.2012.02.009.

Keywords: 35Cl/37Cl isotope effects, 195Pt NMR, 103Rh NMR

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Microsymposia MS.C3.C.11 Reactions of Cubane-type MoIr3S4 and TaIr3S4 Clusters with Hydrazine Compounds Hidetake Seino, Yusuke Shibata, Yuta Manaka, Yasushi Mizobe, Institute of Industrial Science, The University of Tokyo, Tokyo, (Japan). E-mail: [email protected] The cubane-type M4S4 structure is one of representative morphologies of metal sulfido clusters. Fe4S4 clusters are widely found at the active sites of metalloproteins that facilitate electron-transfer and catalysis, and some larger enzymatic clusters contain related structures as subunit. For example, FeMo cofactor of Mo nitrogenase is constituted of incomplete cubane-type Fe4S3 and MoFe3S3 clusters bridged by three μ2-S and one μ6-C atoms. In the study aiming to create functional models of FeMo-co, we have synthesized the cubanetype cluster binding molecular N2, [{Ru(N2)(Me2NCH2CH2NMe2)} (Cp*Ir)3(μ3-S)4] (Cp* = η5-C5Me5) [1]. Although this cluster consists of abiological noble metals, it proves that certain sulfido clusters of high electron count can reductively activate N2 by back-donation. To examine functions of various metals embedded in the electron-rich Ir3S4 subunit, the Ru site of the above cluster was replaced by group 5 or 6 metals, which are relevant to N2-fixation. Reactions of the incomplete cubane-type cluster [(Cp*Ir)3(μ3-S) (μ2-SH)3]Cl (1) with [Mo(CO)3(toluene)] or [W(CO)3(EtCN)3] gave the cubane-type clusters [{M(CO)3}(Cp*Ir)3(μ3-S)4] (M = Mo (2), W). Treatment of 2 with substituted o-quinones in THF led to the formation of [{MoO(cat)}(Cp*Ir)3(μ3-S)4] (3: cat = catecholate) bearing a catecholato chelate and a terminal oxo ligand at the Mo site. Cluster 3a with tetrachlorocatecholato ligand catalyzed reductive cleavage of hydrazines in the system using 2 equiv of Cp2Co and [Et3NH] [BF4] as electron and proton sources, respectively. MePhNNH2 and PhHNNH2 were converted to Ph(R)NH (R = Me, H) and NH3 at room temperature in the presence of 5 mol% 3a. In the conversion of N2H4, 3a showed catalytic activities not only for reduction into NH3 but also for disproportionation to N2 and NH3 in a 1:4 molar ratio. The cubane-type clusters containing group 5 metals [(MCl3) (Cp*Ir)3(μ3-S)4] (M = Nb, Ta (4)) were prepared by reacting the template 1 and equimolar [M(NMe2)5] followed by treatment with excess Me3SiCl. Addition of MeHNNH2 and H2O to a THF suspension of 4 afforded red crystals of the cluster dimer [{(Cp*Ir)3(μ3-S)4(Ta(OH))}2(μ2-O)(μ2-η2:η2-MeHNNH2)]Cl2 (5), in which two cubane-type cores were connected by one oxo and one hydrazine ligands. Treatment of 5 with KPF6 gave the double cubane [{(Cp*Ir)3(μ3-S)4Ta}2(μ2-O)2(μ2-η2:η2-MeHNNH2)][PF6]2 (6) with two oxo and one hydrazine bridges. These clusters have relatively long Ta–N distances (> 2.4 Å), and the N–N bond lengths are comparable to that of free N2H4.

[1] H. Mori, H. Seino, M. Hidai, Y. Mizobe, Angew. Chem. Int. Ed., 2007, 46, 5431-5434.

Keywords: sulfido clusters, cubane-type structure, hydrazines

MS.C3.C.12 Transition metal chemistry of multifunctional hydride-donor ligands Steve Colbran,a Alex McSkimming,a Graham Ball,a Mohan Bhadbhade,b School of Chemistrya and Mark Wainwright Analytical Centre,b University of New South Wales, Sydney (Australia). E-mail: [email protected] Standard protocols for chemical reduction demand the use of relatively expensive and dangerous reagents such as molecular hydrogen or reactive metal hydrides and borohydrides on vast scales. Biology points to an alternative methodology for chemical reduction: direct transfer of hydride from an organo-hydride to a metal-bound and polarized, thus activated, substrate. In biology, the dihydronicotinamide, NADPH, is the principle source of hydride for reduction processes, and directly transfers hydride to substrates in processes as diverse as, for example, the Calvin cycle for fixation and reduction of carbon dioxide to give carbohydrate (food) or fatty acid synthesis in all organisms — including you [1]. The NADPH is regenerated by photosynthesis or respiration. Inspired by biology, we have initiated research into completely abiotic, robust transition metal complexes of multifunctional ligands [3] with organic-hydride-carrier substituents [4, 5]. Following delivery of hydride to metal-bound substrate, we envisage regeneration of the organo-hydride substituent either by electrolysis or by photo-injection of electrons from appropriate dyes or semiconductor particles. Success would lead to a new catalytic methodology for chemical reduction that avoids use of molecular hydrogen or metal hydrides and borohydrides. There is a long way to go! Preliminary results, our first tottering steps towards this long-term goal, will be presented.

[1] (a) N. Pollak, C. Dölle, M. Ziegler, The Power To Reduce: Pyridine Nucleotides – Small Molecules With A Multitude Of Functions, Biochem. J., 2007, 402, 205–218; (b) J. M. Berg, J. L. Tymoczko, L. Stryer, Biochemistry, 6th Ed., © W. H. Freeman, 2007, pp 1120. [2] R. H. Crabtree, Multifunctional ligands in transition metal catalysis, New J. Chem. 2011, 35, 18–23. [3] A. McSkimming, M. Bhadbhade, S. B. Colbran, Hydride-carrier ability in Rh(I) complexes of a nicotinamide-functionalised N-heterocyclic carbene ligand, Dalton Trans. 2010, 39, 10581–10584. [4] A. McSkimming, M. Bhadbhade, G. Ball, S. B. Colbran, Rhodium complexes of a chelating ligand with imidazol-2-

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Keywords: metal-activated, organo-hydride, reduction

MS.C3.C.13 Synthesis and Reactivity of a Cationic Pt(II) Alkylidene Complex Riccardo Peloso, Jesús Campos, Ernesto Carmona, Departamento de Química Inorgánica, Instituto de Investigaciones Químicas (IIQ), Universidad de Sevilla - Consejo Superior de Investigaciones Científicas, Sevilla (Spain). E-mail: [email protected] The last decades have witnessed an explosive growth of interest in the chemistry of transition metal carbenes, [1] due mainly to their important catalytic applications. Great efforts have converged in recent years in platinum- and gold-catalysed reactions that have produced an astonishing variety of products of great structural complexity, by means of experimentally facile transformations of simple and commonly available starting materials. The remarkable catalytic behavior of platinum and gold complexes stems from their unusual Lewis acid properties, in particular from those of their carbene complexes, which are generally proposed as active reaction intermediates. [2] In view of the importance of cationic Pt(II) alkylidenes, [PtII=C(R) (R’)]+, in catalysis [2] we planned to generate and characterize some compounds of this kind. We envisaged that sterically protected platinum bis-metallacycles [3] containing five-membered rings as a result of metalation of aryl phosphine ligands could be suitable candidates for this enterprise, as cationic benzylidene structures could then be readily generated by a-hydride abstraction. At -80 ºC, the bis(platinacycle) trans-Pt{P[2,6-(CH2)(Me)C6H3] Pri2}2, 1, experiences a-hydride abstraction by action of [Ph3C]+[PF6]-, to yield the trans-alkyl-alkylidene complex 2 of moderate thermal stability (t1/2 ca. 44 h at 20 °C). Reactivity studies corroborate the expected electrophilicity of the [Pt=CH]+ unit of 2, which is shown by the following observations: (i) ylide formation by reaction with Lewis bases; (ii) step-wise hydrogenation to afford cationic agostic complexes; (iii) carbene cross-coupling with N2C(H)CO2Et (EDA) to produce the cis and trans isomers of a terminal alkene derivative.

MS.C3.C.14 From Amido to Imido Iridium and Rhodium Complexes Luis A. Oro, Miguel A. Casado e Inmaculada Mena, Instituto de Síntesis Química y Catálisis Homogénea, Departamento de Química Inorgánica Universidad de Zaragoza, CSIC, 50009 Zaragoza, (Spain). E-Mail: [email protected] Amido-bridged polynuclear complexes [{M(µ2-NH2) (diolefine)}x] (M = Ir, Rh; diolefin = 1,5-cyclooctadiene (cod) or tetrafluorobenzobarrelene (tfbb)) can be prepared by treatment of the methoxo-bridged compounds [{M(µ-OMe)(diolefine)}2] with gaseous ammonia in diethyl ether at atmospheric pressure. [1] The nuclearity of these unprecedented parent amido complexes depends on the olefin (trinuclear for tfbb, 1-2, and dinuclear for cod, 3-4). They are active catalysts in hydrogen transfer reactions from isopropanol to unsaturated substrates. The studies performed on the diiridium(I) complex [{Ir(µ2-NH2)(cod)}2] evidences the dinuclear nature of the species involved and the participation of the two iridium centers in the catalytic hydrogen transfer reactions. Interestingly, under the absence of unsaturated substrates the concerted isopropanol dehydrogenation process gives rise to the formation of unusual mixed amido/imido tetraiiridium and bis(imido) triiridium clusters.

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ylidene and pyridin-2-ylidene donors: the effect of C-metallation of nicotinamide groups on uptake of hydride ion, Inorg. Chem. 2012, 51, 2191–2203.

[1] I. Mena, M. A. Casado, P. García-Orduña, V. Polo, F. J. Lahoz, A. Fazal and L. A. Oro, Angew. Chem. Int. Ed., 2011, 50, 11735-11738.

Keywords: Amido, Imido, Clusters

MS.C3.C.15 Molecular Wheels of Ruthenium and Osmium with Bridging Chalcogenolate Ligands: Edge-Shared-Octahedron Structures and Metal-Ion Binding [1] a) Y. Chauvin, Angew. Chem. Int. Ed. 2006, 45, 3740; b) R. R. Schrock, Angew. Chem. Int. Ed. 2006, 45, 3748; c) R. H. Grubbs, Angew. Chem. Int. Ed. 2006, 45, 3760; d) J. A. Arduengo, G. Bertrand, Chem. Rev. 2009, 109, 3209; e) J. W. Herndon, Coord. Chem. Rev. 2011, 255, 3. [2] a) A. Fürstner, Chem. Soc. Rev. 2009, 38, 3208; c) D. Benítez, N. D. Shapiro, E. Tkatchouk, Y. Wang, W. A. Goddard III, F. D. Toste, Nature Chem. 2009; d) B. Trillo, F. López, S. Montserrat, G. Ujaque, L. Castedo, A. Lledós, J. L. Mascareñas, Chem. Eur. J. 2009, 15, 3336; e) A. M. Echavarren, E. Jiménez-Núñez, Top. Catal. 2010, 53, 924. [3] M. Albrecht, Chem. Rev. 2010, 110, 576. [4] Z. Lu, W. M. Jones, W. R. Winchester, Organometallics 1993, 12, 1344.

Keywords: Metallacycles, Alkylidenes, Cross-coupling

Sharon L.-F. Chan,a,b Lam Shek,a Jie-Sheng Huang,a Stephen S.-Y. Chui,a Raymond W.-Y. Sun,a Chi-Ming Che,a aState Key Laboratory of Synthetic Chemistry, Department of Chemistry and Institute of Molecular Functional Materials, The University of Hong Kong. b Department of Applied Biology and Chemical technology, The Hong Kong Polytechnic University. E-mail: [email protected] Considerable efforts have been made to assemble molecular entity into different architectures such as molecular squares, rectangles, polyhedral and etc.[1] The well-defined entity could be further used as a secondary building unit for the assembly of metal-organic framework (MOF) or giant metal clusters.[2] Among the metallomacrocycles, metal molecular wheels are relatively unexplored and are dominated by the 1st row transition metal ions bridged by O-type ligands.[3] Herein, we report the synthesis of Anderson-type molecular wheels of

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Microsymposia 2nd and 3rd transition metal ions (Ru and Os) bridged by chalcogenolate (RS- or RSe-). Despite its intriguing structure, the wheel complex demonstrates a selective binding towards coinage metal ions as revealed from electrospray-ionization mass spectrometry (ESI-MS) and single X-ray crystallography. Density Functional Theory (DFT) calculation has been performed to explore the electronic structures of the wheel complexes. [4]

Computational Chemistry, University of Georgia, Athens, Georgia 30602, USA, bCollege of Science, Northwest A&F University, Yangling, Shanxi 712100, P. R. China, cCenter for Computational Quantum Chemistry, South China Normal University, Guangzhou 510631, P. R. China), d Institute of Chemical Physics, Beijing Institute of Technology, Beijing 100081, P. R. China. E-mail: [email protected] The chemistry of metal thiocarbonyls is much more limited than that of metal carbonyls because of the instability of CS as a synthetic reagent. In view of the many resulting gaps remaining in experimentally realized metal thiocarbonyl chemistry, theoretical studies using density functional methods have been used to explore the possible future scope of metal thiocarbonyl chemistry. This paper surveys the highlights of such theoretical studies on binuclear metal thiocarbonyl derivatives of the types M2(CS)2(CO)n and Cp2M2(CS)2(CO)n (Cp = h5-C5H5; M = V through Ni) as well as the trinuclear and tetranuclear iron carbonyls Fe3(CS)3(CO)n (n = 9, 8, 7, 6) and Fe4(CS)4(CO)n (n = 12, 11, 10, 9). The substitution of one or two CO groups with CS groups to give less symmetrical structures leads to many more isomers. Structures in which a four-electron donor thiocarbonyl group uses its sulfur atom to bridge a metal-metal bond as a h2‑µ‑CS ligand are more favorable in binuclear metal thiocarbonyl chemistry than corresponding structures in metal carbonyl chemistry owing to the basicity of the sulfur atom. Six-electron donor thiocarbonyl groups bridging clusters of three or four iron atoms are also found in low-energy structures including a particularly favorable Fe4(CS)4(CO)10 structure suggested as a possible target for future synthetic chemistry. In thiocarbonyl substitution products of simple binuclear metal carbonyls structures with bridging CS groups are energetically favored over corresponding isomeric structures with bridging CO groups.

MS.C3.C.17

[1] S. Leininger, B. Olenyuk, P. J. Stang, Chem Rev., 2000, 100, 853-908; M. Fujita, K. Umemoto, M. Yoshizawa, N. Fujita, T. Kusukawa, K. Biradha, Chem. Commun., 2001, 509-518. [2] D. J. Tranchemontagne, J. L. Mendoza-Cortés, M. O’Keeffe, O. M. Yaghi, Chem. Soc. Rev., 2009, 38, 1257-1283; H. Chun, D. N. Dybtsev, H. Kim, K. Kim, Chem. Eur. J. 2005, 11, 3521-3529. [3] E. J. Mclnnes, S. Piligkos, G. A. Timco, R. E. P. Winpenny, Coord. Chem. Rev. 2005, 249, 2577-2590. [4] S. L.-F. Chan, L. Shek, J.-S. Huang, S. S.-Y. Chui, R. W.-Y. Sun, C.-M. Che, Angew. Chem. Int. Ed. 2012, 51, 2614-2617.

Keywords: Molecular wheels, chalcogenolate, self-assembly

MS.C3.C.16 Structural Changes upon Replacing Carbonyl Groups With Thiocarbonyl Groups in First Row Transition Metal Derivatives: New Insights R. Bruce King,a Zhong Zhang,b,c Qian-shu Li,c,d Yaoming Xie,a and Henry F. Schaefer,a Department of Chemistry and Center for

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A bis-palladium complex for CO2 activation Caterina Gruenwaldt,a Benjamin List,b Henrique E. Toma,a aChemistry Institute, University of São Paulo, São Paulo, (Brazil). b Department of Organocatalysis, Max-Planck Institute für Kohlenforshung, Mülheim a.d. Ruhr, Nord-Rhein-Westfalen (Germany). E-mail: [email protected] Carbon dioxide, as renewable resource, is the ideal carbon source for synthesis due to its abundance, price and low toxicity. During a long period of time, CO2 was thought to be a poorly reactive molecule, however, nowadays transition metal complexes are being pursued for activation purposes, in order to allow its coupling to other molecules. [1] Such coupling reactions provide real “gold mines” in chemistry, by aggregating value to CO2 while fulfilling the global warming prospects. Analogous to Heck, Suzuki and Stille reactions, CO2 was used to obtain carboxylic acids from coupling to double bounds, organoboron and organotin reagents. However, little has been done regarding its coupling to alkanes. The best examples are the studies involving methane and CO2 activation with palladium and vanadium compounds to obtain acetic acid under harsh conditions. [2] [3] [4] A complex able to activate an alkane and CO2 at the same time would be ideal. Such bi-functional complex could perform the carboxylation of alkanes with CO2. Accordingly, we synthesized a bimetallic complex composed of two catalytic sites of palladium (1). The synthesis of the desired complex (BPP(OPPh2Pd,OPPh2Pd), (1), was accomplished by using a modified Trost ligand and two equivalents of palladium chloride. Characterization was performed by IR, EDX, 1 H, 13C and 31P NMR spectrometry, satisfactory microanalysis and mass spectrometry. After bubbling carbon dioxide in a solution of (1), IR and UV-Vis spectroscopy data supported the formation of a CO2 bridge between the two palladium sites by means of a m2-h3, class II coordination. This type of complex, in the presence of methyl iodide, gives

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rise to methyl acetate. Carbon dioxide is hence activated by the BPP(OPPh2Pd,OPPh2Pd) complex. Cyclic voltammetry and spectroelectrochemistry of the complex, revealed two main processes at 1.2 and 1.59V, which can arise from the (Pd(II)-Pd(II) → Pd(II)-Pd(III) and Pd(II)-Pd(III) → Pd(III)-Pd(III)) processes, in addition to the phenol oxidation, observed in the free ligand at 1.3V. After CO2 bubbling, the two waves collapse into a single process, suggesting the break of the intervalence interactions promoted by the CO2 insertion between the two metal centeres. Finally, it was shown that this complex is able to promote CO2 insersion in a C-H bound of an alkane photochemically [5], converting iso-octane and CO2 into the 2,2,4,4-tetramethyl pentanoic acid.

(1)

[1] D.H. Gibson, Coord.Chem. Rev., 1999, 185-186, 335. [2] M. Zerella, M. S., A.T. Bell, Org. Lett., 2003, 5, 3193-3196. [3] Y. Fujiwara, H. Taniguchi, K. Takaki, M. Kurioka, T. Jintoku, T. Kitamura, Stud. Surf. Sci.Catal., 1997, 107, 275. [4] E.M. Wilcox, G.W. Roberts, J.J. Spivey, Appl. Catal. A, 2002, 226, 317–318. [5] R.H. Crabtree, Photosensitization and photocatalysis using inorganic and organometallic compounds, Kluwer Academic Publishers, Amsterdam, 1993.

Keywords: Carbon dioxide, Palladium complex, Reduction catalysis

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9 - 13 September 2012

MS.D1.KN1 Therapeutic and Diagnostic Metal Complexes in Medicinal Inorganic Chemistry Chris Orvig, Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver BC (Canada). E-mail: [email protected] The role of metal complexes as therapeutic and diagnostic agents is burgeoning due to interest from many academic and industrial concerns; the current value of medicinal inorganic chemistry is in excess of $109. Cisplatin, for example, is the archetypal inorganic drug containing as it does, no atoms of carbon. Principles in the design of metal compounds as drugs will be discussed in detail with examples from work in the speaker’s research laboratories presented to illustrate these principles. These examples are taken from our group’s work in insulin-enhancing vanadium compounds, diagnostic and therapeutic radiopharmaceuticals, and multifunctional agents for neurodegenerative diseases and malaria. Keywords: medicinal inorganic chemistry, therapy, diagnosis

MS.D1.KN2 Progress and Trends in Radiometal-Based Theranostics R. Schibli,a,b aDept. of Chemistry and Applied Biosciences, ETH Zürich 8093 Zürich (Switzerland). bCenter for Radiopharmaceutical Science ETH-PSI-USZ Paul Scherrer Institute, CH-5232 Villigen-PSI (Switzerland), E-mail: [email protected] Early and precise diagnosis and effective therapy of disseminated tumors are of paramount importance because metastases often results in poor prognosis for the patient. Application of tumor-seeking molecules labeled with diagnostic radionuclides (γ-emitters for SPECT; β+emitters for PET) is currently one of the most sensitive methodologies for the non-invasive detection of cancer in vivo. Systemic delivery of molecules radiolabeled with particle emitting radionuclides such as α-, β-- and Auger-emitters allow destruction of disseminated tumors. It is important to recognize that with a few examples like most radionuclides currently used in nuclear medicine or in development are transition metals and lanthanides (e.g. 67/68Ga, 89Zr, 99mTc, 111In, 177 Lu etc.). The production of such radionuclides and moreover their stable and rapid incorporation into tumor targeting molecules represent a challenging tasks for inorganic and bioinorganic chemistry. This lecture will include the presentation of strategies for the production of new radiometals preparation of new bifunctional metal chelating systems e.g. via “click-chemistry” and novel technologies for the bio-orthogonal and enzymatic functionalization of vitamins, peptides and antibodies. Selected preclinical and clinical examples of the development of novel vitamin B9 and B12 radiotracers and antibodies with different radiometal for diagnosis and potential therapy of various cancer types will be presented. Keywords: Cancer, Diagnosis, Therapy

MS.D1.I1 Gd(III)-based MRI Contrast Agents: Strategies in the Design of Novel Structural Platforms Teresa Rodríguez-Blas, Adrián Roca-Sabio, Aurora RodríguezRodríguez, Martín, Regueiro-Figueroa, David Esteban-Gómez, Carlos Platas-Iglesias, Andrés de Blas. Departamento de Química Fundamental. Universidade da Coruña (Spain), E-mail: [email protected].

MRI contrast agents are a group of contrast media used to improve the visibility of internal body structures in magnetic resonance imaging (MRI). These agents improve the image contrast by preferentially influencing the relaxation efficiency of water proton nuclei in the tissue of interest. The first and even nowadays most commonly used compounds for contrast enhancement are gadolinium-based complexes. For clinical application, these Gd(III)-based contrast agents (GBCAs) must fulfill a minimum of requirements: i) the presence of at least one Gd(III)-bound water molecule rapidly exchanging with the bulk water of the tissue; ii) a high relaxivity, which is a measure of the efficiency of a contrast agent defined as the relaxation-rate enhancement of water protons per mM concentration of metal ion; and iii) a high thermodynamic and/or kinetic stability under physiological conditions to prevent the release of toxic free Gd(III) ion in vivo. Particular attention deserves this last point due to the appearance of the Nephrogenic Systemic Fibrosis (NSF), a serious syndrome associated with exposure to certain GBCAs in patients with severe kidney failure. Depending on their ability to release free Gd(III) ion in the body, the European Medicine Agency has classified the GBCAs in three groups, considering those containing a macrocyclic skeleton as the safest ones. Moreover, babies and young children have immature kidneys and the GBCAs approved for clinical use nowadays cannot be injected in this case, or must be done in very low dose, making difficult the enhancement of the image contrast. Therefore, the development of safe GBCAs also for paediatric diagnosis is a real challenge today. On the other hand, the majority of the GBCAs used in vivo are unspecific. During the last years a great effort has been done in order to develop new compounds with higher specificity. Although some blood pool agents have been already approved and are used in vivo at the present time, many efforts continue being focused on the development of other specific agents including targeting (i.e. tumor-specific agents) and organ specific agents, as well as intelligent (responsive and pHsensitive) MRI agents, what in all cases requires functionalization of the basic skeleton of the Gd(III) complex. With regard to all of this, we are interested in the search of novel structural entries for the design of GBCAs highly stable and easy to functionalize. It is known that the pyridinecarboxylate group provides a strong binding to the lanthanide(III) ions. This one, together with its bidentate coordinating nature, makes this group very useful to be attached to azamacrocyclic frameworks in order to provide ligands that: i) ensure a high stability of Gd(III) complexes in water; ii) may provide octadentate binding to the metal ion leaving one coordination position available for an inner-sphere water molecule; and iii) may leave nitrogen atoms of the azamacrocycle available for further easy functionalization. Different strategies and examples will be presented. Keywords: Contrast Agents, MRI, Picolinates

MS.D1.I2 Metal Coordinated Nano-Sized Macromolecules for Intravascular and Organ-Specific Diagnoses Katayoun Saatchi1, Pavel Gershkovich1, Kishor M. Wasan1, Stefan A. Reinsberg2, Jennifer H.E. Baker3, Donald E. Brooks4, Francois Benard3 and Urs O. Häfeli, 1Faculty of Pharmaceutical Sciences, 2Department of Physics and 4Centre for Blood Research, University of British Columbia, 4British Columbia Cancer Research Agency; Vancouver, British Columbia, Canada. E-mail: [email protected] The importance of imaging in clinical diagnosis and cancer research is beyond words! All different imaging techniques utilized today such as X-ray, SPECT, PET and MRI have their own advantages and applications. However, all these techniques have different characteristics with respect to tissue contrast, depth penetration,

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Microsymposia spatial resolution, imaging time and cost. This validates combining these techniques to improve upon the limitations of each. As a result the interest in multimodal imaging has grown vastly over the past few years. A good contrast agent has a suitable circulating concentration and time, and high uptake in the target tissue. Having multiple probes on the same carrier molecule is preferred and obviates the need to administer two or more compounds with somewhat different pharmacokinetics. Many classes of macromolecules have been investigated to date as contrast agents. Examples include liposomes, block copolymers, micelles, dendrimers and even nanoparticles each modified with one or more imaging probes. This report summarizes our findings on a highly promising platform for a diagnostic (and potentially theranostic) agent. Initially synthesized and investigated as human serum substitute[1], high molecular weight hyperbranched polyglycerols (HPG) are globular macromolecules with radii of less than 10 nm (depending on molecular weight). Due to HPG’s ease of syntheses and modification, and missing toxicity and hemocompatibility, HPG are proven excellent mono- or multi-modality imaging bioprobes. Upon modifications with radioactive, MRI contrast enhancing, and fluorescent tags, HPG becomes a versatile tool for detection with PET, SPECT, MRI, and fluorescent imaging. Example applications of HPG are blood pool imaging (using 111In or 67Ga for SPECT imaging, 68Ga for PET imaging and Gd for MRI) and the investigation of vessel leakiness and perfusion in tumours. Further applications to explore will incorporate specific targeting molecules such as antibodies and peptides to enhance accumulation in the target tissue; allow for enhanced drug delivery and lead to chemotherapy with drug-filled HPG with reduced side effects and toxicity. HPG is therefore the ideal theranostic macromolecule for extensive use in preclinical research, clinical diagnostic and even potentially for therapy. Acknowledgements This research was jointly funded by a research/operating grant “Alternative radiopharmaceuticals for medical imaging” from the Canadian Institutes of Health Research (CIHR) and the Natural Sciences and Engineering Research Council of Canada (NSERC). [1] Kainthan RK, Janzen J, et al. Biomaterials 2008, 29, 1693-1704.

Keywords: Radiopharmaceuticals, imaging, macromolecules

MS.D1.I3 From Studying Vanadium-containing Anti-Diabetic Agents to Formulation of Platinum-containing Anti-Cancer Agents Debbie C. Crans, Department of Chemistry, Colorado State University 80523-1872, USA. Email: [email protected] Vanadium compounds are known insulin-enhancing agents, and as such a range of derivatives have been investigated for potential treatment [1,2]. Even though these compounds are presumed to inhibit protein tyrosine phosphatases, recent investigations investigated the potential function of these compounds at the membrane. The interactions of a range of metal complexes with interfaces and the lipid-like environment were found to affect the properties and thus the permeability of metal complexes [3]. The characterization of the Nano sized materials in combination with animal studies have allowed testing approaches to make materials that can be used for administration of a drug in tandem with targeting agent or co-drug. Lipid gels loaded with carboplatin and the targeting agent cholesterol were intracavitary administered after surgical removal of tumors [4]. Formulations have been designed with the concept of promoting a synergistic relationship between the drugs, coupling taxol’s antisarcoma potency with bisphosphonate agent’s tendency to concentrate

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at bone resorption sites as well as its treatment of hypercalcemia correlated with cancer malignancy. Model studies carried out using NMR and Langmuir monolayer studies combined with dynamic light scattering data with either the anionic AOT or the catonic surfactant cetyl trimethylammonium bromide systems documented the formation of organized self-assembled structures in the formulations tested. Acknowledgement. DCC thank all her students and collaborators for their contributions and NSF and NIH for funding. [1] K. H. Thompson, J. Lichter, C. LeBel, M. C. Scaife, J. H. McNeill, C. Orvig. J. Inorg. Biochem. 2009, 103, 554-558. [2] Debbie C. Crans, Alejandro M. Trujillo, Philip S. Pharazyn, and Mitchell D. Cohen Coor. Chem. Rev. 2011, 1920, 2178-2192. [3] Samantha Schoeberl, Debbie C. Crans, Alan K. Van Orden, B. George Barisas and Deborah A. Roess Dalton Transactions, 2012, 41(21), 6419-6430. [4] Kellie A. Woll, Elie J. Schuchardt, Claire R. Willis, Christopher D. Ortengren, Ernestas Gaidamauskas, Deanna R. Worley, David W. Osborne and Debbie C. Crans Chemistry & Biodiversity 2011 8, 2195-2210.

MS.D1.C.01 A Macrobicyclic Ligand for Targeted Cancer Imaging Brett M. Paterson,a Delphine Denoyer,b Carleen Cullinane,b Peter Roselt,b Jonathan M. White,a Rodney J. Hicks,b and Paul S. Donnelly,a a School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, (Australia). bPeter MacCallum Cancer Centre, Melbourne, (Australia). E-mail: brettp@ unimelb.edu.au Somatostatin-based radiolabelled peptides have made a genuine impact on both diagnostic and therapeutic patient care. The somatostatin analogue Tyr3-octreotate has a high capacity for binding to primary tumours and metastases, including neuroendocrine tumours, which express the somatostatin receptor subtype 2 (SSTr2). Targeted diagnosis and therapy also requires a suitable imaging and therapeutic radionuclide. The radionuclide 64Cu possesses emissions suitable for positron emission tomography (PET) and radiotherapy and its half-life of 12.7 h is ideal for regional cyclotron production and distribution. Macrobicyclic sarcophagine molecules form exceptionally stable complexes with 64Cu, preventing early release of the radionuclide and ensuring safe clinical use. The sarcophagine compound 5-(8-methyl-3,6,10,13,16,19hexaazabicyclo-[6.6.6]eicosan-1-ylamino)-5-oxopentanoic acid (L1) was synthesised and the copper(II) complex, CuL1(ClO4)2 was characterised by x-ray crystallography. The chelator possesses a carboxylic acid functional group that was used for coupling to the N-terminus of Tyr3-octreotate on solid phase. The resulting peptide conjugate, L1-Tyr3-octreotate, was labelled with 64Cu in high yield and good specific activity at room temperature. The radiolabelled conjugate retains high affinity for SSTr2 over-expressed by A427-7 cells. The conjugate selectively accumulates in mouse A427-7 xenografts and this tumour accumulation is combined with fast clearance from nontarget tissue via the kidneys. The L1-Tyr3-octreotate conjugate possesses promising pharmacokinetic properties for in vivo imaging of SSTr2-positive tumours and a clear potential for translation into the clinic.

Microsymposia tool for screening the biological activity of recombinant proteins using 99m Tc and 188Re labelling. Identification of sequences suitable for other types of specific modification is achievable using the high-throughput screening method. [1] R. Tavare, R. Torres Martin de Rosales, P. J. Blower, G. E. D. Mullen. Bioconjugate Chem 2009, 20, 2071-2081.

Keywords: Radiopharmaceuticals, Imaging, Cancer

MS.D1.C.03 MS.D1.C.02 Amino acid sequences for fast site-specific protein labelling with M(CO)3+ (M=99mTc, 188Re) Jennifer Williams, Gregory Mullen, Phil Blower, Division of Imaging Sciences and Biomedical Engineering, and Division of Chemistry, King’s College London, London, UK. E-mail: Jennifer.Williams@kcl. ac.uk Introduction: Radiolabelling proteins with radiometals Tc99m and Re-188 for molecular imaging and radionuclide therapy is challenging due to potential interference of the radiolabel at the active site and consequent loss of affinity of the protein for its target. For synthetic peptides, site-specific labelling has been achieved by introducing amino acid building blocks attached to chelators to the sequences. However, this approach is not applicable to proteins as they can only be produced recombinantly. Hexahistidine tags (histags) used for protein purification can be used for direct radiolabelling with [M(CO)3]+ (M = 99mTc, 188Re) but labelling efficiency varies from protein to protein and is often unsatisfactory. We have previously demonstrated1 that the presence of a cysteine in combination with the his-tag substantially improved the labelling of the generic his-tag with [99mTc(CO)3]+. To optimise the design of the metal binding sequence further, we have developed a high-throughput screening methodology using combinatorial peptide arrays. This method is suitable for the identification of genetically encodable tags based on amino acid sequences which provide a site of unique reactivity for the specific labelling of biomolecules with a radioisotope of choice. Using this high-throughput screening methodology we have identified a superior amino acid sequence, CLRRRLAHHHHHH (known as JenTag), for radiolabelling with [M(CO)3]+ (M = 99mTc, 188Re). Method: Combinatorial peptide libraries were produced containing 384 specifically designed peptides in duplicate, at 4.91 pmol per spot. These arrays were used in a high-throughput screening methodology: incubated with [99mTc(CO)3]+ for 15, 30, 60 and 120 minutes; washed with serum for 1, 2 and 18 hours; and incubated at a pH of 5.1, 7.4 and 8.8 with citrate, tris and phosphate buffer respectively. Additional radioisotopes including other 99mTc complexes, 188Re and 64Cu were also tested. Results: The combinatorial library has demonstrated its ability to provide an efficient and straightforward method for the identification of novel sequences for coordination to radioisotopes and also for the optimisation of the radiolabelling conditions required. It was found that for coordination with [99mTc(CO)3]+ peptide sequences required the presence of at least one histidine, a high isoelectric point (pI>10) and a cysteine residue within 3-6 amino acids away from the his-tag. Labelling was best achieved at 37oC, pH 7.4 in PBS buffer. The JenTag demonstrated 8 fold higher radiolabelling efficiency at 15 minutes (p 18 hours in serum. Conclusion: Incorporating the JenTag has the ability to offer a fast and efficient method for the site-specific labelling of any recombinant protein with [99mTc(CO)3]+. Consequently it is a potent

Coordination Complexes of Gallium(III) and Antimicrobial Resistance Katja Dralle, Michael J. Abrams, Chris Orvig, Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, Vancouver (Canada). E-mail: [email protected] The World Health Organization (WHO) has identified the resistance of microbes to known antimicrobial drugs as one of the greatest threats to human health, because it hampers the control of infectious diseases, threatens a return to the pre-antibiotic era and jeopardizes the achievements of modern medicine; in addition, it increases global health care costs [1]. New antimicrobial agents that target new biological sites of action are needed to overcome the growing antimicrobial resistance. One potential target is iron metabolism. Iron is critical for the metabolism and growth of most organisms, and many animal species, including humans, limit the availability of iron at the site of infection as a mechanism of host defense [2]. Ga3+ shares many chemical similarities with Fe3+, which makes it difficult for biological systems to distinguish the two metals; however, the +3/+2 redox chemistry essential for the iron metabolism cannot be accessed for gallium, which leads to cellular toxicity. Consequently, Ga3+ has been stamped as the Trojan horse in biological systems [3]. In a coordination chemistry approach to new potential metalloantimicrobials, our group has synthesized gallium(III) complexes of the (fluoro-)quinolones, a class of synthetic broadspectrum antibiotics. The corresponding iron(III) complexes were included in the antimicrobial susceptibility studies to further explore the structure-activity-relationship and to test the Trojan horse theory. Acknowledgements. The University of British Columbia is acknowledged for a Four Year Doctoral Fellowship (K.D.) and the Natural Sciences & Engineering Research Council of Canada for a Discovery Grant. [1] WHO (2012). Antimicrobial resistance [Fact sheet]. Retrieved from www. who.int/mediacentre/factsheets/fs194/en/. [2] U.E. Schaible, S.H.E. Kaufmann, Nat. Rev. Microbiol., 2004, 2, 946-954. [3] Y. Kaneko, M. Thoendel, O. Olakanmi, B.E. Britigan, P.K. Singh, J. Clin. Invest., 2007, 117, 877-888.

Keywords: antimicrobial, bioinorganic, gallium

MS.D1.C.04 Copper ligands to combat Alzheimer’s disease Christelle Hureau,a,b Sabrina Noël,a,b Sarah Cadet,a,b Madeleine Jensen,a,b Isabelle Sasaki,a,b Emmanuel Gras,a,b Peter Faller,a,b aCNRS; Laboratoire de Chimie de Coordination, Toulouse, (France); b Université de Toulouse, UPS, INPT; LCC; Toulouse, (France). E-mail: [email protected] Alzheimer’s Disease (AD) is a multifactorial disease, in which the amyloid-β peptide takes a central role. Indeed it is found as

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Keywords: technetium, rhenium, radiolabelling

Microsymposia aggregated forms in the senile plaques detected in AD patients’ brains, where it is co-localized with high concentrations of metal ions (Cu, Zn, Fe). Hence, it has been proposed that such ions can modulate the aggregation process of the monomeric Aβ peptide found in healthy brains. Redox active ions such as Cu or Fe are also linked to AD via the production of Reactive Oxygen Species (ROS) such as H2O2 and HO● that leads to oxidative stress, another factor thought to be important for AD progression [1]. In the last years, we have been mainly interested in disentangling the intricate role of Cu ion into processes linked to the aetiology of the disease (Cu coordination to Aβ and its influence on aggregation and oxidative stress) [2-4]. This was a necessary step to design new therapeutic tools able to interfere with the deleterious impacts of Cu in both the aggregation process of Aβ and in the Cu(Aβ) ROS production. More recently, different strategies to obtain Cu ligands that can prevent Cu induced Aβ aggregation and/or stop Cu(Aβ) ROS production have been developed in our group. For in vitro studies, having watersoluble counterparts of such ligands is a key issue since solvent such as DMSO can interfere with classical in vitro assays for aggregation and ROS production. Hence, several Cu(I) and Cu(II) ligands, including bi-functional molecules incorporating an Aβ-targeting moiety and a Cu coordinating unit [5], have been obtained and characterized. Their impacts on both the Cu induced aggregation process of Aβ and the Cu(Aβ) ROS production will be shown and discussed.

[1] C. Hureau, Coord. Chem. Rev., 2012, in press. [2] C. Hureau, Y. Coppel, P. Dorlet, P. L. Solari, S. Sayen, E. Guillon, L. Sabater and P. Faller, Angew. Chem., Int. Ed. Engl., 2009, 48, 9522-9525. [3] V. Balland, C. Hureau, J.-M. Savéant, Proc. Natl. Acad. Sci. U. S. A., 2010, 107, 17113-17118. [4] B. Alies, B. Badei, P. Faller and C. Hureau, Chem. Eur. J. 2012, 18 1161-1167. [5] M. Jensen, A. Canning, S. Chiha, P. Bouquerel, J. T. Pedersen, J. Østergaard, O. Cuvillier, I. Sasaki, C. Hureau and P. Faller, Chem. Eur. J. 2012, 18, 4836-4839.

Keywords: Copper, ligands, Alzheimer

MS.D1.C.05 fac-{99mTcO3}+-Complexes: Versatile Precursors for Imaging Probe Development Henrik Braband, Sebastian Imstepf, Michael Benz, Roger Alberto, Institute of Inorganic Chemistry, University of Zurich, Winterthurerstr. 190, 8057 Zurich, Switzerland. E-mail: [email protected] Tc is a very practical nuclide for nuclear medical applications due to its availability from generators, its short physical half-life time (6 h), and the emission of low energy g-rays (140.5 keV). Today, 90% of all nuclear medical treatments involve 99mTc-containing drugs.[1] We are aiming at a general understanding of the reactivity of technetium at its highest oxidation state +VII. Our research foremost focuses on compounds containing the fac-{99(m)TcO3}+-core, due to its interesting chemical reactivities ((3+2)-cycloaddition with alkenes).[2] To make these complexes accessible for a broad range of investigations, new 99m

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methods for their synthesis needed to be developed. Activation of [99TcO4]- by reaction with strong Lewis acids and the oxidation of stable Tc+V and Tc+I complexes are new opportunities for the synthesis of fac-{99TcO3}+-complexes.[3-6] Recently, the first synthesis of a negatively charged fac-{99TcO3}+-complex, [99TcO3(nota)]2- (nota = 2,2’,2’’(1,4,7-tria­zonane-1,4,7-triyl)triacetat, was achieved by the oxidation of [99Tc­(nota∙2H)­(CO)3] with sodium perborate.[6] At the tracer level phosphates were used to develop a synthesis for fac-{99mTcO3}+-complexes.[4] A main aim of our research is the establishment of a new labeling strategy based on the reactivity of fac-{99mTcO3}+-complexes with alkenes ((3+2)-cycloaddition) to enable new opportunities for nuclear medicine.[4-6] Water stable [99mTcO3(tacn-R)]+ type complexes (tacn-R = 1,4,7-triaza­cyclo­nonane and derivatives) are versatile precursors for this approach. First biodistribution studies of the hydrophilic [99mTcO3(tacn)]+ showed that the bioprofile of this compound differs fundamentally from the well known precursor [99mTc(OH2)3(CO)3]+ which unspecifically binds to blood pool proteins, thereby inhibiting a fast clearance from the body (essential for imaging). To demonstrate the potential and flexibility of the (3+2)-cyclo­addition labeling concept, the Fmoc-protected 1-allyl-Lhistidine, as a possible single amino acid chelate (SAAC) analouge,[7] and the monosaccharide allyl 2,3,4,6-tetra- O-acetyl-β-(D)-gluco­pyra­ noside were synthesized and labeled with [99mTcO3(tacn)]+.[5] Finally, the flexibility that fac-{99mTcO3}+ complexes introduce into the imaging probe synthesis allowed us to devise a new mixed (3+2)-cycloadditionBFC approach for the development of bifunctionalized radioprobes.[6]

[1] F. Roesch, F. F. Knapp, Handbook of Nuclear Chemistry. Kluwer Academic Publishers: 2003, 4, 81-118. [2] R. M. Pearlstein, A. Davison, Polyhedron, 1988, 7, 1981-1989. [3] Y. Tooyama, H. Braband, B. Spingler, U. Abram, R. Alberto, Inorg. Chem. 2008, 47, 257-264. [4] H. Braband, Y. Tooyama, T. Fox, R. Alberto, Chem. Eur. J., 2009, 15, 633-638. [5] H. Braband, Y. Tooyama, T. Fox, R. Simms, J. Forbes, J. F. Valliant, R. Alberto, Chem. Eur. J. 2011, 17, 12967-12974. [6] H. Braband, S. Imstepf, M. Benz, B. Spingler, R. Alberto, Inorg. Chem. 2012, 51, 4051-4057. [7] M. Bartholomä, J. F. Valliant, K. P. Maresca, J. Babich, J. Zubieta, Chem. Commun. 2009, 493-512.

Keywords: technetium, radiopharmacy, (3+2)-cycloaddition

MS.D1.C.06 Macrobicyclic amine chelators for 68Ga and 64Cu radiopharmaceuticals Michelle Ma,a Oliver C. Neels,b Delphine Denoyer,b Margaret S. Cooper,a Jonathan M. White,c Philip J. Blower,a Rodney J. Hicks,b Paul S. Donnelly,c* aDepartment of Imaging Chemistry and Biology, King’s College London, London (United Kingdom). bThe Centre for Molecular Imaging and Translational Research Laboratory, The Peter MacCallum Cancer Centre, Melbourne, (Australia). cSchool of Chemistry, The University of Melbourne, Parkville (Australia). With the advent of the application of high resolution positron emission tomography (PET) to the diagnosis of disease, new bifunctional chelators for the positron-emitting metallic radionuclides, 64 Cu and 68Ga, have been developed. Metal complexes of the macrobicyclic amine ligand, 3,6,10,13,16,19-hexaazabicyclo-[6.6.6] icosane (commonly referred to as “sarcophagine”) exhibit remarkable stability as a result of the encapsulating nature of the chelator. We have characterised the first reported Ga3+ sarcophagine complex and report details of a sarcophagine-peptide conjugate labelled with 68 Ga.[1] This tracer consists of a bifunctional sarcophagine ligand

tethered to two αVβ3 integrin-targeting peptides (1). This species can be labelled in > 99 % radiochemical yield. Stability studies demonstrate that 68Ga3+ does not dissociate from 1 in the presence of the endogenous Ga3+-binding protein, transferrin. Biodistribution and micro-PET imaging studies (see Figure) in tumour-bearing mice indicate that 1 accumulates specifically in tumours with high integrin expression and that non-specific uptake and clearance properties of the tracer are favourable for diagnostic imaging purposes. Detailed radiochemical studies and in vivo studies of a 64Cu-labeled antibody are also reported, in which a bifunctional sarcophagine ligand has been conjugate to rituximab, a therapeutic antibody used to treat leukemia and lymphoma.[2,3] The 64Cu-sarcophagine-rituximab conjugate can be synthesised in high radiochemical yield and high specific activity, and in vivo studies demonstrate high complex stability.

[1] M. T. Ma, O. C. Neels, D. Denoyer, P. Roselt, J. A. Karas, D. Scanlon, J. M. White, R. J. Hicks, P. S. Donnelly, Bioconj. Chem., 2011, 22, 2093–2103. [2] M. S. Cooper, M. T. Ma, K. Sunassee, K. P. Shaw, J. D. Williams, R. L. Paul, P. S. Donnelly, P. Blower, Bioconj. Chem., 2012, in press, DOI: 10.1021/ bc300037w. [3] M. T. Ma, M. S. Cooper, R. L. Paul, K. P. Shaw, J. A. Karas, D. Scanlon, J. M. White, P. J. Blower, P. S. Donnelly, Inorg. Chem., 2011, 50, 6701–6710.

Keywords: PET imaging, radiopharmaceuticals, sarcophagine

4-oxo-1,4-dihydro-pyridin-2-ylmethyl)-amide], which binds Ga-68 extremely rapidly at very low concentration. For this to succeed, the chelator must transchelate Ga-68 previously bound to transferrin under in vivo conditions. We explored the possibility of pretargeting using metal chelation by administering an antibody-CP256 conjugate followed by Ga-68 citrate. Methods: In vitro studies were performed with free CP256 and Ga-68 acetate in serum, with analysis by TLC and size exclusion chromatography. For in vivo studies, the macrophage-binding antibody SER4 was coupled with YM103, a maleimide derivative of CP256. There were three groups of 2-3 wild type or sialoadhesinknockout mice. Group 1 received prelabelled Ga-67/68 YM103-SER4 (positive control), Group 2 received unmodified SER4 followed by Ga-67/68 citrate (negative control), and Group 3 received YM103SER4 followed by Ga-67/68 citrate (pretargeting). Imaging was performed using NanoPET/CT (Mediso) followed by sacrifice and tissue counting. Results: In vitro studies showed that CP256 rapidly and efficiently bound Ga-68 in serum, even if the Ga-68 had been incubated with serum and bound to transferrin prior to addition of CP256. Under similar conditions no labelling of NOTA (1,4,7-triazacyclononaneN,N’,N’’triacetic acid), an established chelator used for Ga-68 labelling, was detectable. In the wild type mice, Group 1 showed targeting of macrophages in the spleen (36% ID/g) whereas Group 2 showed only 4% in the spleen. Group 3, with pretargeting, showed 10% in the spleen. In the sialoadhesin knockout mice there were no differences in splenic activity between groups, indicating the role of macrophage sialoadhesin in targeting. NanoPET/CT images showed spleen and liver activity in Group 3 but only blood pool and joints in Group 2. Conclusions: The feasibility of a simple pretargeting approach using a CP256-conjugated antibody followed by Ga-68 citrate has been demonstrated. Further work will optimise the interval between antibody and radiotracer administration. [1] D. J. Berry, Y. Ma, J. R. Ballinger, E. Tavaré, A. Koers, K. Sunassee, T. Zhou, S. Nawaz, G. E. D. Mullen, R. C. Hider, P. J. Blower. Chem Commun, 2011, 47, 7068 - 707.

Keywords: gallium, imaging, PET

MS.D1.C.07 Metal ion chelation as a basis for pretargeting with gallium-68 for PET imaging Phil Blower, Maggie Cooper, Saima Nawaz, Alex O’Neill, Alex Koers, Kavitha Sunassee, David Berry, Gregory Mullen, Jim Ballinger, Division of Imaging Sciences and Biomedical Engineering, King’s College London; and Department of Nuclear Medicine, Guy’s and St Thomas’ Hospital, London, UK. E-mail: [email protected] Radiometals such as Ga-68 attached to molecular targeting agents such as proteins and peptides are important in medical imaging using positron emission tomography (PET). Short half life isotopes are preferred to minimise radiation dose, but slow molecular targeting processes (e.g. using monoclonal antibodies) are not compatible with the short half life. A potential solution is pretargeting, in which an unlabelled antibody conjugate is allowed to clear from circulation before a radiolabelled chaser is administered that binds to the antibody conjugate. The avidin-biotin system, with antibody is conjugated to avidin/streptavidin and the radionuclide conjugate to biotin, has been used most widely. Click chemistry and related bio-orthogonal approaches have also been explored but surprisingly, metal chelation has not. We developed[1] a high-affinity tripodal tris(hydroxypyridinone) chelator, CP256 (CP256 = 4-Acetylamino-4{2-[(3-hydroxy-1,6-dimethyl-4-oxo-1,4-dihydro-pyridin-2-ylmethyl)carbamoyl]-ethyl}-heptanedioic acid bis-[(3-hydroxy-1,6-dimethyl-

MS.D1.C.08 Molecular imaging applications based on Ln3+ complexes Eva Toth, Centre de Biophysique Moléculaire, CNRS, Orléans (France). E-mail: [email protected] In the last two decades, lanthanide coordination chemistry has witnessed a spectacular evolution, largely promoted by the successful use of lanthanide complexes in biomedical applications. Millions of clinical magnetic resonance imaging (MRI) examinations are carried out after the injection of Gd3+ chelates. Emerging applications in molecular imaging seek a real-time, repeatable, in vivo visualization of molecules or molecular events at the cellular and tissue level. One important field in molecular imaging involves the in vivo detection of physico-chemical parameters of tissues, concentration of ions, metabolites, etc. by applying smart, activatable imaging probes that are responsive to the specific parameter to detect. In contrast to nuclear imaging modalities, MRI is particularly well adapted to the design of responsive probes, involving Gd3+-based or PARACEST (Paramagnetic Chemical Exchange Saturation Transfer) agents. The efficacy (relaxivity or CEST properties) of the probe has to be selectively influenced, based on coordination chemistry concepts, by the particular biomarker that we wish to detect. In this presentation, we will report on potential smart contrast agents to detect cation concentration changes or to monitor enzyme activity.

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Microsymposia We have developed smart MRI agents designed to detect Ca2+ concentration changes in the extracellular space. Ca2+ is crucial at several steps during neuronal signalling, and its intra- and extracellular concentration changes dramatically during brain activity. Our Ca2+ sensitive CAs are capable of reversible Ca2+ binding and subsequently altering their magnetic properties. We have recently reported on a versatile platform of PARACEST agents designed for specific detection of a wide variety of enzymes. The molecular design involves coupling an enzyme specific substrate to a lanthanide chelating unit via a self-immolative spacer. The approach is based on the intrinsic instability of benzyloxycarbamates possessing an electron donor substituent in ortho or para position. With benzyloxycarbamates as self-immolative unit, the substrate can be any enzyme-recognized moiety capable of transitionally reducing the electron donor capabilities of the phenyl substituent. [1] T. Chauvin, P. Durand, M. Bernier, H. Meudal, B.-T. Doan, F. Noury, B. Badet, J.-C. Beloeil, É. Tóth, Detection of Enzymatic Activity by PARACEST MRI: A General Approach to Target a Large Variety of Enzymes, Angewandte Chemie, Int. Ed. 2008, 47, 4370-4372. [2] T. Chauvin, S. Torres, R. Rosseto, J. Kotek, B. Badet, P. Durand and É. Tóth, Lanthanide(III) complexes bearing a self-immolative arm: potential enzyme responsive contrast agents for magnetic resonance imaging, Chem. Eur. J, 2012, 18, 1408–1418. [3] C. S. Bonnet and E. Toth, Magnetic resonance imaging probes for sensing biologically relevant metal ions, Future Medicinal Chemistry, 2010, 2, 367-384.

Keywords: lanthanide, contrast agents, MRI

MS.D1.C.09 New Gold Thiolates Containing Aminoacid Moieties with Antitumoral Properties M. Concepción Gimeno,a Alejandro Gutierrez,a Javier Bernal,a Antonio Laguna,a M. Dolores Villacampa,a Carlos Cativiela,a Lucía Gracia,b Soledad Isern de Val,b Isabel Marzo,b aInstituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Zaragoza, (Spain). bDepartamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, Zaragoza (Spain). E-mail: [email protected] In recent years the interest in non-platinum metal complexes for cancer chemotherapy has been rapidly growing and being stimulated by the possibility to develop new agents with a mode of action and clinical profile different from the established platinum drugs. Gold complexes have gained much attention because of their strong antiproliferative effects and the observation that they inhibit the enzyme thioredoxin reductase (TrxR) with high potency and specificity [1]. A series of gold complexes containing aminoacid and peptide moities have been prepared starting from the thiolate complexes [Au(SpyCOOH)(PPh3)] or [Au2(m-SpyCOOH)(PPh3)2](CF3SO3) by coupling with the corresponding aminoacid ester derivatives. The aminoacid ester derivatives were reacted with LiOH or amines to afford the corresponding acid or amide compounds (Scheme 1). Cytotoxic studies towards several cell lines, such as Jurkat (T cell leukaemia), A549 (adenocarcinomic human alveolar basal epithelial cells) and MiaPaca2 (pancreas carcinoma) have been performed using the MTT viability assay. The complexes exhibited activity with IC50 values ranging from 2.4-8.6 mM in Jurkat cells and for the solid tumours ranging from 6.9-30.5 mM. The gold complexes with the proline ester derivative showed the highest activity in all cell lines. Preliminary studies of interaction of compounds with cells were carried out with the goal of increasing the knowledge on the mechanism of action of these potential drugs.

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Scheme 1. i) [AuCl(PPh3), K2CO3, ii) aminoacid ester, pyBOP, DIPEA, iii) LiOH, MeOH, iv) iPrNH2, pyBOP, DIPEA [1] I. Ott, Coord. Chem. Rev., 2009, 253, 1670-1681.

Keywords: gold complexes, cytotoxic activity, thioaminoacids

MS.D1.C.10 Zinc-Specific Fluorescent Response of Quinoline-Based Tripodal Ligands Yuji Mikataa and Keiko Kawata, KYOUSEI Science Center, Nara Women’s University, Nara (Japan). E-mail: [email protected] Zinc ions are indispensable metal ions in living systems. Zinc plays many important structural and catalytic roles in enzymes, and is one of the key components in cellular processes including gene expression and signal transduction. Fluorescent zinc sensor molecules have been extensively developed in recent years, aiming at the visualization and/ or quantification of the dynamic and transient zinc ion distribution inside the cell. We have previously reported that N,N,N’,N’-tetrakis(2quinolyl-methyl)ethylenediamine (TQEN) can act as a fluorescent zinc detection molecule.[1] The structure of TQEN is based on wellknown heavy metal chelator, N,N,N’,N’-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN). The 1- and 3-isoTQEN, isoquinoline derivatives of TQEN, exhibited improved properties compared to TQEN.[2] In this study, isoquinoline-based tripodal ligands, tris(1- or 3-isoquinolylmethyl)amine (1- or 3-isoTQA), have been prepared and their zinc-induced fluorescence enhancement was investigated.[3] The structure of isoTQAs is related to tris(2-pyridylmethyl)amine (TPA) or its quinoline derivative, TQA. Upon excitation at 324 nm, 1-isoTQA shows very weak fluorescence (f = ~0.003) in DMF/H2O (1/1) solution. In the presence of zinc ion, 1-isoTQA exhibits fluorescence increase (f = 0.041) at 359 and 470 nm. This fluorescence enhancement at 470 nm is specific for zinc. On the other hand, 3-isoTQA exhibited a smaller fluorescence enhancement upon zinc complexation (f = 0.017, lem = 360 and 464 nm) compared with 1-isoTQA. Crystal structures of zinc complexes of isoTQAs demonstrate the diminished steric crowding and shorter Zn-Naromatic distances compared with isoTQENs leads to a higher fluorescent response toward zinc relative to cadmium. [1] Y. Mikata, M. Wakamatsu, and S. Yano, Dalton Trans., 2005, 545-550. [2] Y. Mikata, A. Yamanaka, A. Yamashita, and S. Yano, Inorg. Chem., 2008, 47, 7295-7301. [3] Y. Mikata, K. Kawata, S. Iwatsuki, and H. Konno, Inorg. Chem., 2012, 51, 1859-1865.

Keywords: zinc, quinoline, fluorescence

Microsymposia MS.D1.C.11 When Chemical Kinetics Meets Radiopharmaceutical Design: Focus on [Re(CO)3]+ Hendrik G. Visser,a Andreas Roodta, Marietjie Schuttea, Alice Brinka, Gerdus Kemp,b aDepartment of Chemistry, University of the Free State, Bloemfontein, (South Africa). bPetlabs, Little Company of Mary Hospital, Pretoria, (South Africa). E-mail: [email protected]

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Significant interest has been shown over the past decade or more in rhenium and technetium complexes, bearing the fac[M(CO)3(H2O)3]+ entity (M = Tc(I), Re(I)), as potential diagnostic and therapeutic radiopharmaceuticals respectively [1, 2]. Characteristics which render these complexes so attractive for application in nuclear medicine include the inert [M(CO)3]+ core and the relative labile water molecules bound to it. This work describes the aqua and methanol substitution reactions of fac-[M(CO)3(L-L’-Bid)(X)]n (L-L’-Bid = neutral or monoanionic bidentate ligands with varied L,L′ donor atoms, N,N′, N,O, or O,O′: 1,10-phenanthroline, 2,2′-bipydine, 2-picolinate, 2-quinolinate, 2,4-dipicolinate, 2,4-diquinolinate, tribromotropolonate, tropolonate (Trop) and hydroxyflavonate; X = methanol/H2O; n = 0, 1) and the relevance to radiopharmaceutical design following the [2 + 1] approach [3, 4, 5]. A four order-of-magnitude of activation for the methanol substitution is induced as manifested by the second order rate constants with (N,N’-Bid) < (N,O-Bid) < (O,O’-Bid). Forward and reverse rate and stability constants (k1, M-1s-1; k-1, s-1; K1, M-1) from slow and stopped-flow UV/vis measurements for pyridine ligands as entering nucleophile range from (6.4 ± 0.3) x 10-5, (5.8 ± 0.3) x 10-6, 11 ± 1 to 1.38 ± 0.08, 3 ± 1) x 10-1, 4600 ± 100 for L-L’-Bid = 1,10-phenanthroline and hydroxyflavonate respectively. A dissociative interchange mechanism is proposed, confirmed by a high-pressure kinetics study. The aqua substitution of fac-[M(CO)3(Trop)(H2O)] was also followed at various pH levels and as expected it was found that fac-[M(CO)3(Trop)(OH)]- is unreactive towards substitution. The acid dissociation constant (pKa1) was determined as 9.04 ± 0.02 and is very favourable for future kit design (saline solution at pH = 7). Another important aspect from this part of the study is that the water substitution reactions are 10 times faster than the corresponding methanol substitutions as indicated by the second order rate constants. Finally, the methanol substitution reactions between fac[M(CO)3(L-L’-Salen)(MeOH)] (L-L’-Salen = a range of salicylidene derivatives) are presented and yields very interesting results in terms of the rate law obtained from spectroscopic kinetic studies. Overall, the large variation in rate and the different rate laws obtained from seemingly simple substitution reactions by simply modifying the characterestics of the bidentate ligand in fac-[M(CO)3(LL’-Bid)(X)]n illustrates the importance of mechanistic studies in radiopharmaceutical design. [1] R. Alberto, R. Schibli, R. Waibel, U, Abram, A.P. Schubiger, Coord. Chem. Rev.., 1999, 192, 901-919. [2] F. Zobi, O. Blacque, R.K. Sigel, R. Alberto, Inorg. Chem, 2007, 46, 10458-10460. [3] B. Salignac, P.V. Grundler, S. Cayemettes, U. Frey, R. Scopeletti, A. Merbach, Inorg. Chem., 2003, 42, 3516-3526. [4] P.V. Grundler, L. Helm, R. Alberto, A. Merbach, Inorg. Chem., 2006, 45, 1037810390. [5] M. Schutte, G. Kemp, H.G. Visser, A. Roodt, Inorg. Chem., 2011, 50, 12486-12498.

Keywords: Radiopharmaceuticals, Kinetics, Rhenium(I)

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Merging Metal-Nucleobase Chemistry with Supramolecular Coordination Chemistry Bernhard Lippert, Fakultät Chemie, Technische Universiät Dortmund, 44221 Dortmund (Germany). E-Mail: [email protected] The past two decades have witnessed a fruitful merging of (bioinorganic) metal-nucleobase chemistry with supramolecular coordination chemistry in numerous disciplines such as medicinal chemistry, materials sciences, analytical chemistry, and nanotechnology. The lecture will provide a brief overview on these developments and will subsequently focus on topics from the author’s laboratory. These include discrete 2D- and 3D-supramolecular complexes between model nucleobases and N-heterocyclic ligands in general with metal units such as cis- or trans-a 2 M(II) (with a = am(m)ine and a 2 = diamine; M = Pt or Pd). While some of these complexes can be considered artificial analogs of naturally occurring structures (e.g. of Guanine quartets in quadruplex DNA),[1] others represent constructs without any natural prototype, being composed exclusively of metal units and nucleobases and displaying versatile topologies (L-, U-, Z-shape; vases, open boxes, closed tetrahedron).[2, 3] Because of their cationic nature, these compounds have a high affinity for anions, including for negatively charged nucleic acids. [1] B. Müller, W.-Z. Shen, P. J. Sanz-Miguel, F. M. Albertí, T. van der Wijst, M. Nogera, L. Rodríguez- Santiago, M. Sodupe, B. Lippert, Chem. Eur. J., 2011, 17, 9970 – 9983. [2] S. Ibanez, F. M. Albertí, P. J. Sanz Miguel, B. Lippert, Chem. Eur. J. , 2011, 17, 9283 – 9287. [3] B. Lippert, P. J. Sanz Miguel, Chem. Soc. Rev., 2011, 40, 4475 – 4487, and refs. cited.

Keywords: nucleobases, architectures

platinum

complexes,

molecular

MS.D2.KN2 Dipyridophenazine Complexes and DNA; Photophysics and Crystallographic Studies John M. Kellya and Christine J. Cardin,b aSchool of Chemistry, Trinity College Dublin, Dublin 2, Ireland bSchool of Chemistry, University of Reading, Reading RG6 6AD, UK.. E-mail: [email protected]; [email protected] For many years of metal polypyridyl complexes have been extensively studied as probes for DNA. Of particular importance are dipyrido[3,2-a:2’,3’-c] phenazine (dppz) complexes which bind to DNA though intercalation of the heteroaromatic ligand between the base-pairs of the polynucleotide.1 The complex [Ru(phen)2(dppz)]2+ (phen = 1,1-phenanthroline) has attracted special attention as it acts as a DNA-light switch, being non-luminescent in water but luminescent when bound to DNA.[1] Other complexes such as [Ru(TAP)2(dppz)]2+ [2], [Cr(phen)2(dppz)]3+, [3] (TAP = 1,4,5,8-tetraazaphenanthrene) show contrasting behaviour as they are luminescent in aqueous solution but their emission is quenched upon binding to DNA, due to reduction of the metal complex excited state by guanine. The behaviour of the Dand Λ- enantiomers when bound to DNA and the effect of 11,12 –dppz substitution in [M(phen)2dppzR2]3+ (M = Ru, Cr; R = F or Me) will be discussed. Picosecond transient spectroscopic studies (both visible and IR monitoring) with [Ru(TAP)2(dppz)]2+ and with [Re(CO)3(dppzF2) (py)] + [4] provide insights into the nature of the electron transfer processes. Despite the very large numbers of studies carried out with [Ru(phen)2(dppz)]2+ and related compounds, the precise mode of

binding deduced from spectroscopic and biophysical measurements has been a matter of debate. Recent successful crystallisation by the Reading Group of both [Ru(phen)2(dppz)]2+ and Ru(TAP)2(dppz)]2+ [5] with small defined sequence DNA has for the first time provided a wealth of information on the interaction of these complexes with DNA and allowed a comparison with other DNA- intercalating molecules. This talk will relate the structural observations of groove, sequence and enantiomer preference to the intercalation angles observed and hence provide detailed insights into the solution behaviour. Acknowledgements. This work has been supported by Science Foundation Ireland and the Royal Society/Royal Irish Academy. The authors are grateful to their coworkers in Trinity College and the University of Reading and to their collaborators Andrée Kirsch- De Mesmaeker (Brussels), Michael W. George (Nottingham), Anthony W. Parker (Rutherford Appleton Laboratories) and their research teams. [1] B.M. Zeglis, V.C. Pierre, J.K. Barton, Chem Comm. 2007, 44, 4565–4579. [2] B. Elias, C. Creely, G. W. Doorley, M. M. Feeney, C. Moucheron, A. Kirsch De Mesmaeker, J. Dyer, D. C. Grills, M. W. George, P. Matousek, A. W. Parker, M. Towrie, J. M. Kelly, Chemistry – Eur. J, 2008, 14, 369-375. [3]. M. Wojdyla, J. A. Smith, S. Vasudevan, S. J. Quinn J. M. Kelly, Photochem. Photobiol. Sci., 2010, 9, 1196-1202. [4]. Q. Cao, C. M. Creely, J. Dyer, T. Easun, D.C. Grills, D. A. McGovern, J. McMaster, J. Pitchford, J. A. Smith, X.-Z. Sun, J. M. Kelly, M. W. George, Photochem. Photobiol. Sci., 2011, 10, 1355-1364. [5] J. P. Hall, K. O’Sullivan, A. Naseer, J. A. Smith, J. M. Kelly, C. J. Cardin, Proc. Natl. Acad. Sci., 2011, 108, 17610-17614.

MS.D2.I1 Metalation of non-coding RNA – a complementary mode of action for platinum-based drugs? Sofi Elmroth, Biochemistry and Structural Biology, Department of Chemistry, Lund University, POBox 124, SE-221 00 Lund, (Sweden). E-mail: [email protected] Clinical treatment of cancers typically involves the use of several regimens. Often, protein targeting is combined with so called “alkylating drugs” that are capable of modifying nucleic acid structure by covalent interaction. In the latter case, the use of platinum based drugs has been particularly successful. The first discovered compound cisplatin still remains the most frequently used metal-based anticancer drug worldwide, however with carbo- and oxaliplatin as frequently used alternatives.[1] The mode of action of these platinum-based compounds is known to involve DNA-binding, and result in downstream effects on both replication and transcription.[2] However, both our group and others have reported experimental studies showing that also RNA can be effectively targeted by these drugs.[3-5] In our laboratory, one particular aim is to elucidate how sensitive the mi- and siRNA-controlled translational machinery is towards drug exposure. Both mi- and siRNAs are duplex RNAs that are prone to platination.[3] In cellular systems, the siRNAs take advantage of an endogenous system allowing for sequence-specific recognition of a target mRNA by Watson-Crick base-pairing using the so called seedsequence as the guide. We have previously shown that both cellular uptake and repressive function of siRNAs remains efficient after platination.[6-7] In addition, metalation of siRNAs outside of the seedregion was recently reported to fine tune silencing capacity, typically by reducing silencing ability.[8] At present, we are in the process of also evaluating the effect of drug interference with the seed region. The here observed changes of protein production after platination will be discussed in light of tentative effects on miRNA-level, e.g. effects on production of proapoptotic- and tumor suppressor proteins. [1] For a recent review see: L. Galluzzi, L. Senovilla, I. Vitale et al. Oncogene, 2012, 31, 1869-1883. [2] R. C. Todd and S. J. Lippard Chemistry & Biology, 2010, 17, 1334-1343. [3] M. Hagerlof, P. Papsai, C. S. Chow and S.K.

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Microsymposia C. Elmroth, JBIC, 2006, 11, 974-990. [4] K. Rijal and C. S. Chow, Chemical Communications, 2009, 107-109. [5] A. A. Hostetter, M. F. Osborn and V. J. DeRose, ACS Chemical Biology, 2012, 7, 218-225. [6] M. Hagerlof, H. Hedman, H. and S. K. C. Elmroth, BBRC, 2007, 361, 14-19. [7] A. S. Snygg and S. K. C. Elmroth, BBRC, 2009, 379, 186-190. [8] H. K. Hedman, F. Kirpekar and S. K. C. Elmroth, JACS, 2011, 133, 11977-11984.

Keywords: platin, RNA, protein production

MS.D2.I2 Regulating gene expression by interaction of metal complexes with quadruplex DNA Ramon Vilar, Department of Chemistry, Imperial College London, South Kensington, London SW7 2AZ (United Kingdom). E-mail: [email protected] Recent bio-informatic studies have established that in the human genome there are ca. 350,000 guanine-rich sequences that can potentially form quadruplex DNA. Some of these sequences have been identified as targets for the development of novel anticancer drugs. Therefore there is great current interest in developing small molecules that can selectively interact with quadruplex DNA and study their potential as anticancer drugs. We have previously investigated the quadruplex DNA binding properties of several families of transition metal complexes;[1-5] more recently, we have shown by X-ray crystallography the binding mode between some of these complexes and quadruplex DNA.[6] In this lecture, our most recent results in this area will be presented. More specifically, it will be shown that a series of metal complexes (based on platinum, zinc, copper, vanadium and nickel) can have very high affinity and good selectivity for quadruplex DNA. The ability to fine tune the binding abilities of these complexes towards a given topology of DNA by changing the ligand framework will also be discussed. In addition, the cellular behaviour of some of these complexes will be discussed in the context of their ability to act as anticancer agents and optical probes.

In vivo applied Mn+ display a rather weak affinity and high dynamics in RNA binding, making it highly challenging to investigate their binding, location, and effect on RNA function. Here we present our results from our interdisciplinary approach including NMR, potentiometric pH titrations, single molecule FRET, and database mining to understand the diverse factors that place a given metal correctly within a complex RNA fold: A new calculation tool, ISTAR, helps us to determine intrinsic metal ion-affinity constants of given sites within RNAs.[4] Combined with NMR experiments and a stability concept, that relies on the stability increments provided by individual coordinating atoms, specific coordination patterns can be deduced.[5] In addition to more stronger coordination sites, e.g., N7 or the phosphate group, also 2’OH functionalities are rather common and also important in complex RNA architectures.[6] Complementary to the above experimental techniques, the Metal Ions in Nuclei AcidS (MINAS) database enables a PDB-wide search for specific coordination patterns in all to-date solved structures of nucleic acids.[7] Such, we have just evaluated the occurrence of ion-p interactions in nucleic acids. Well-known from small molecules and protein structures,[8] we also identified numerous in RNAs: phosphate groups, Na+ and Mg2+ (Figure), but also lysine and arginine residues are commonly found above the aromatic planes of purines and pyrimidines adding their share to stabilize the threedimensional structure and to mediate RNA-protein interactions.[9]

[1] J.E. Reed, A. Arola, S. Neidle, R. Vilar, J. Am. Chem. Soc., 2006, 128, 5992. [2] A. Arola, J. Benet-Buchholz, S. Neidle, R. Vilar, Inorg.Chem. 2008, 47, 11910. [3] K. Suntharalingam, A.J.P. White, R. Vilar, Inorg.Chem. 2009, 48, 9427. [4] K. Suntharalingam, A.J.P. White, R. Vilar, Inorg.Chem. 2010, 49, 8371. [5] S.N. Georgiades, N.H. Abd Karim, K. Suntharalingam, R. Vilar, Angew. Chem. Int. Ed. 2010, 49, 4020. [6] N.H. Campbell, N.H. Abd Karim, G.N. Parkinson, M. Gunaratnam, V. Petrucci, A.K. Todd, R. Vilar, S. Neidle, J. Med. Chem. 2012, 55, 209.

Keywords: DNA, Quadruplex, Cancer

MS.D2.I3 Metals Ions in RNA: Uncommon Coordination Patterns within Complex Architectures Roland K. O. Sigel, Institute of Inorganic Chemistry, University of Zurich, Zurich (Switzerland). E-mail: [email protected] Metal ions are crucial for RNA folding, structure and function: Aside from charge compensation of the negatively charged phosphate units, they occupy key sites to mediate tertiary contacts, stabilize local architectures, as well as to enable and fine tune catalytic activity. [1] For example, the catalytic activity of the Hammerhead ribozyme in the presence of different M2+ is directly related to the respective affinity of the ion towards phosphates.[1] In contrast, trace amounts of Ca2+ inhibit group II intron splicing and lead to two distinct folding pathways and subpopulations.[2,3]

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Financial support by the European Research Council, the Swiss National Science Foundation and the University of Zurich is gratefully acknowledged. [1] J. Schnabl, R. K. O. Sigel, Curr. Op. Chem. Biol., 2010, 14, 269-275. [2] M. C. Erat, R. K. O. Sigel, J. Biol. Inorg. Chem., 2008, 13, 1025-1036. [3] M. Steiner, D. Rueda, R. K. O. Sigel, Angew. Chem. Int. Ed., 2009, 48, 97399742. [4] M. C. Erat, J. Coles, C. Finazzo, B. Knobloch, R. K. O. Sigel, Coord. Chem. Rev., 2012, 256, 279-288. [5] R. K. O. Sigel, H. Sigel, Accounts Chem. Res., 2010, 43, 974-984. [6] F. M. Al-Sogair, B. P. Operschall, A. Sigel, H. Sigel, J. Schnabl, R. K. O. Sigel, Chem. Rev., 2011, 111, 4964-5003. [7] J. Schnabl, P. Suter, R. K.O. Sigel, Nucleic Acids. Res., 2012, 40, D434-D438. [8] A. Frontera, P. Gamez, M. Mascal, T. J. Mooibroek, J., Reedijk, Angew. Chem. Int. Ed. 2011, 50, 9564-9583; M. M. Gromiha, C. Santhosh, S. Ahmad, Int. J. Biolog. Macromol. 2004, 34, 203-211. [9] J. Schnabl, R. K. O. Sigel, 2012, to be submitted.

Keywords: RNA, ribozyme, MINAS

MS.D2.C.01

MS.D2.C.02

Xanthosinate 5’-Monophosphate. Metal Ion Affinity of Individual Binding Sites Helmut Sigel, Astrid Sigel, University of Basel, Dept. of Chem., CH4056 Basel, Switzerland. E-mail: [email protected]

Anti-tumor, Anti-inflammatory and Anti-coagulant Effects of Re and Cu complexes Christiana A. Mitsopoulou,a Zabelou Patiniotia, Michail Kaplanisa, Alexandros Tsouprasb, Georgios Stamatakisb, Konstantinos Demopoulosb, Maria Paravatouc, aLaboratory of Inorganic Chemistry, Faculty of Chemistry, National and Kapodistrian University of Athens 15771 (Greece).bLaboratory of Biochemistry, Faculty of Chemistry, National and Kapodistrian University of Athens (Greece).cInstitute of Radiosotopes &Radiodiagnostic Products, NCSR Demokritos, Athens15310 (Greece). E-mail: [email protected]

Xanthosine and its derivatives play important roles, e.g., in the purine metabolism. In textbooks the structure of xanthosine 5’-monophosphate (XMP2–) is commonly shown in analogy to the one of guanosine 5’-monophosphate (GMP2–) with a deprotonated phosphate group and a neutral xanthosine residue. Unfortunately, this structure is not correct for the physiological pH range of ca 7.6 [1-3]: Monoprotonated XMP2–, i.e., H(XMP)–, is deprotonated at the xanthine moiety with pKa = 5.30 ± 0.02 [1], the phosphate group still being monoprotonated, hence, XMP2– needs to be written as (X – H·MP·H)2–. This species loses its H+ from P(O)2(OH)– with pKa = 6.45 ± 0.02 [1] and exists thus at pH 7.6 overwhelmingly as (X – H·MP)3–, whereas the guanine moiety of GMP2– is neutral at this pH because of pKa = 9.49 ± 0.02 [1,3]. A tautomeric equilibrium exists for the (X – H·MP)3–species and its xanthosinate residue: (N3)–/(N1)H (N3) H/(N1)– [3]. The (X – H·MP·H)2– species forms complexes with Mg2+, Ca2+, 2+ Mn , Co2+, Cu2+, Zn2+, etc.; they all have M2+ coordinated at the N7/ (C6)O site (see below) and H+ at the phosphate group and are therefore best written as (M·X – H·MP·H)±. Interestingly, the nucleobase-bound M2+ form macrochelates with P(O)2(OH)–; their average formation degree amounts to 64 ± 9% (3s), independent of the kind of M2+. This can only be explained by an outersphere interaction with P(O)2(OH)– [3]. Of course, in complexes formed with (X – H·MP)3–, leading to M(X – H·MP)–, the phosphate group is the primary binding site and this ‘open’ form is designated as (X – H·MP·M)op–. In this case also ‘closed’ or macrochelated species, (X – H·MP·M)cl–, occur between the phosphate-coordinated M2+ and N7, possibly also involving an outersphere interaction with (C6)O. Here, the various M2+ behave as individuals and thus the extent of macrochelate formation varies; i.e., it amounts for Mn2+, Cu2+, and Zn2+ to about 50, 95, and 88%, respectively. Because the M2+ affinity of the phosphate group and the xanthinate moiety (for the dichotomy see [4]) can be individually evaluated. A recently developed method [5] quantifying the chelate effect can be applied allowing to calculate the formation degrees of the various isomeric complexes. For example, for Zn(X – H·MP)– one calculates [3] that 85.2% are present in the chelated form, (X – H·MP·Zn)cl–, and that 14.8% exist as ‘open’ isomers, that is, in 12.1% of the species Zn2+ is phosphate-coordinated and in 2.7% it is at the xanthinate moiety. Supported by the Department of Chemistry of the University of Basel.

[1] S.S. Massoud, N.A. Corfù, R. Griesser, H. Sigel, Chem. Eur. J., 2004, 10, 5129-5137. [2] E. Kulikowska, B. Kierdaszuk, D. Shugar, Acta Biochim. Polonica, 2004, 51, 493-531 [Review]. [3] H. Sigel, B.P. Operschall, R. Griesser, Chem. Soc. Rev., 2009, 38, 2465-2494. [4] A. Sigel, B.P. Operschall, H. Sigel, Coord. Chem. Rev., 2012, 256, 260-278. [5] M.J. Sánchez-Moreno, A. Fernández-Botello, R.B. Gomez-Coca, R. Griesser, J. Ochocki, A. Kotynski, J. Niclós-Gutiérrez, V. Moreno, H. Sigel, Inorg. Chem., 2004, 43, 1311-1322.

The antitumor activity of the inorganic complex cis-diamminedichloroplatinum(II) (cisplatin) led to the development of other types of non-organic cytostatic drugs. In general, the use of metal complexes as potential pharmaceutics is increasingly gaining ground. Numerous other platinum and non-platinum metal compounds were shown to be effective against animal model tumors as well as tumors in man [1], [2], [3]and references therein. In cancer, malignant situations such as angiogenesis and metastatic progression are strongly promoted by the inflammatory tumor microenvironment due to high levels of cytokine and chemokine secretion by the recruited inflammatory and stromal cells. Blood coagulation, inflammatory activation of platelets, monocytes and endothelial cells are typical steps in such situations and occur as a common mechanistic effect of an inflammatory network of mediators such as thrombin, factor X, tissue factor, fibrinogen, von Willebrand factor, platelet-activating factor (PAF), several cytokines and growth factors [4]. Taking into consideration the important applications of a-diimine Re(I) and Cu(I) metal complexes it becomes evident that the synthesis and characterization of new coordination complexes with these metals, is an issue of special interest. In this study, we further explored the synthesis of several Re and Cu metal complexes along with their in vitro effects against PAF-induced biological activities and anticancer effects. For this purpose, the potent inhibitory effect of these metal complexes was studied on PAF-induced platelet aggregation toward both washed rabbit platelets (WRPs) and rabbit platelet rich plasma (PRP). Moreover, the inhibitory action of some of these complexes towards thrombin was also investigated, in order to prove their selectivity with respect to either the PAF- or the thrombin-dependent platelet aggregation. In addition, these metal compounds were also tested for their ability to modulate PAF-basic metabolic enzymes activities in preparations of rabbit leukocytes. In vitro cytotoxicity properties of the ligands and their respective Re(I) and Cu(I) complexes were assessed using MTT colorimetric method, [5]. The human breast (MCF-7), prostate (PC3) and glioblastoma (T98G) cells were treated with a wide range of concentrations of molecules. It is interest that the Re complex which is active against these cancer cell lines, similar to cis-platin is also the most active against PAF and thrombin. [1] C. A. Mitsopoulou, C. Dagas, Bioinorg. Chem. & Appl., 2010, Artcl No 977342. [2] C. A. Mitsopoulou, C. E. Dagas, C. Makedonas, Inorg. Chim. Acta, 2008, 361, 1973. [3] C. A. Mitsopoulou, C. E. Dagas, C. Makedonas, J. Inorg. Biochem., 2008, 102, 77. [4]A. B. Tsoupras, C. Iatrou, C. Frangia, and C. A. Demopoulos, Infectious Disorders—Drug Targets, 2009, 9, 390. [5] S. Tzanopoulou, M. Sagnou, M. Paravatou-Petsotas, E. Gourni, G. Loudos, S. Xanthopoulos, D. Lafkas, H. Kiaris, A. Varvarigou, I. C. Pirmettis, M. Papadopoulos, M. Pelecanou, J. Med. Chem., 2010, 53, 4633.

Keywords: rhenium(I), copper(I), anticancer effects

Keywords: chelate effect, isomeric complexes, nucleotides

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Microsymposia

Microsymposia MS.D2.C.03 Computational Study of Biological Systems: Cd in DNA Bases Helena. M. Petrillia, Philippe A. D. Petersenª, Marcos. B. Gonçalvesª, Ana Maria C. Ferreirab, aDepartment of Materials Physics, Institute of Physics, University of São Paulo, São Paulo, (Brazil).bDepartment of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, (Brazil). E-mail: [email protected] Important steps towards understanding bio-molecular behavior are structural and electronic structure investigations, aiming the study of local interactions. A powerful promising tool to provide information in a nanometer scale, around a given probe atom, is to explore hyperfine interactions, which can be measured by different techniques. In the case of electric hyperfine interactions, the nuclear quadrupole moment of the probe atom interacts with the charges in its surroundings. The measured quantity in these nuclear quadrupole interactions, is usually expressed through the tensor product of the nuclear quadrupole moment and the electric field gradient at the nucleus (EFG). The EFG can nowadays be calculated with very high precision using ab-initio electronic structure calculations what helps interpreting experimental results and also to estimate the adequacy of molecular models in different conditions. It is known that the structure and function of DNA may be changed upon interaction with metal ions [1]. For example, many aspects of the base pairing can be modified by binding Cd ions to DNA bases, accordingly to the binding site [2]. Here, we perform electronic structure calculations in the framework of the Kohn-Sham scheme of the Density-Functional Theory (DFT) [3] to study different coordination features of Cd bound to DNA basis. Particular emphasis is given to EFG results and energetic analysis. The computational code used is the Projector Augmented Wave Method [4] combined with the Car-Parrinello [5] scheme (CP-PAW). [1] J. V. Burda, J. Sponer, P. Hobza, J. Phys. Chem., 1996, 100, 7250. [2] J. V. Burda, J. Sponer, J. Leszczynski, P. Hobza, J. Phys. Chem. B., 1997, 101, 9670. [3] W. Kohn, L. J. Sham, Phys. Rev. B., 1965, 140, 1133. [4] P. E. Blochl, Phys. Rev. B., 1994, 50, 17953. [5] R. Car e M. Parrinello, Phys. Rev. Lett., 1985, 55, 2493.

Keywords: DFT, DNA Bases, Cd

MS.D2.C.04 Scorpiand-like polyamines. Interaction with DNA and Nucleotides. Mario Inclán,a Enrique García-España,a M. Teresa Albelda,a Juan C. Frías,a Salvador Blasco,a Antonio García-España,b Carolina Serena.b a Institute for Molecular Science, University of Valencia, Valencia, (Spain). bInstitut de Investigació Sanitaria Pere Virgili (IISPV), University Rovira i Virgili, Tarragona (Spain). E-mail: mario.inclan@ uv.es Scorpiand ligands are polyamines consisting of a “fixed” macrocyclic core appended with an arm containing additional amine donor groups, and were prepared by Lotz and Kaden for the first time [1]. The pendant arm is flexible enough to fold and bind the metal ion encircled by the macrocycle, on a similar way as the tail of a scorpion. Previous studies show how this molecular motion can be controlled by the pH of the solution and by the presence or absence of metal ions [2]. We demonstrate now how the metal-induced intramolecular rearrangements affect the DNA intercalation ability of the compounds, and how these changes drastically affect their biological properties. We have also studied the stability of the species formed by our scorpiand receptors and different nucleotides, in order to explore the nucleotide-recognition capability of the protonated polyamines.

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[1] Lotz, T. J.; Kaden, T. A. J. Chem. Soc., Chem. Commun. 1977;15. [2] Blasco, S., Verdejo, B., Clares, M.P., Castillo, C. E., Algarra, A. G., Latorre, J., Máñez, M.A., Basallote, M. G., Soriano, C., García-España, E. Inorg. Chem. 2010; 49, 15, 7016.

Keywords: polyamine, DNA, nucleotide

MS.D2.C.05 Self-assembly of guanosine derivatives into functional nanostructures

Sushobhan Ghosh,a Ramon Vilar,a aDepartment of Chemistry, Imperial College London, London (UK). E-mail: [email protected] and [email protected] Non-covalent interactions can be efficiently used for the construction of supramolecular architectures. A biologically relevant assembly that lends itself well to synthetic supramolecular chemistry is the guanine-quartet, which is a H-bonded structure composed of four Hoogsteen-paired guanine bases. Guanine self-assembly in lipophilic systems governed by H-bonding interactions has been the focus of much research in the past. Supramolecular assemblies can also be developed using guanosines substituted with metal ligands. This can then lead to hierarchical assemblies that come together by a combination of metal-ligand coordination and H-bonding interactions. We have recently synthesized a new guanosine derivative, G1, substituted with a terpyridine subunit (see Scheme). When reacted with copper(II) nitrate in methanol G1 forms a supramolecular rectangle (G4) which has been characterized by spectroscopic means as well as X-ray single crystal structure determination. There is considerable evidence that the formation of quadruplexes in vivo in guanine-rich regions of the genome may play important roles in regulating gene expression [1]. There are several small molecules designed so far which can interact with the quadruplex structure of these gene sequences. Apart from purely organic DNA quadruplex binders, metal complexes have emerged as efficient and selective quadruplex DNA binders [2]. Our group has recently shown that metal complexes of terpyridinebased ligands can interact very strongly with quadruplex structures formed by c-myc and human telomeric DNA[3]. In the context of this project, we were interested in finding out whether the supramolecular terpyridine assembly G4 could interact strongly with the G-tetrad by end-stacking. In addition, due to its larger supramolecular structure we intended to enhance the selectivity for quadruplex vs. duplex DNA. Hence the structure may become a unique example of a selective quadruplex DNA binder molecule. The preliminary evidence of the selective interaction of G4 with quadruplex DNA was found by Fluorescent Intercalator Displacement (FID) assay. The details of the interaction of the molecule G4 with several quadruplex-forming sequences will be presented.

Microsymposia MS.D2.C.07

[1]. Balasubramanian, S.; Neidle, S. Curr. Opin. Chem. Biol. 2009, 13, 345. [2]. Georgiades, S. N.; Karim, N. H. Abd. ; Suntharalingam, K. ; Vilar, R. Angew. Chem. Int. Ed. 2010, 49, 4020. [3]. a) Suntharalingam, K..; White, A. J. P.; Vilar, R. Inorg. Chem. 2010, 49, 8371; b) Suntharalingam, K..; White, A. J. P.; Vilar, R. Inorg.Chem. 2009, 48, 9427.

Keywords: Molecular square, DNA, Quadruplex

MS.D2.C.06 Bifunctionality in design of metal-based antitumor compounds Jan Reedijk, Leiden Institute of Chemistry, Gorlaeus Laboratories, P.O. Box, 9502, 2300 RA, Leiden University, Leiden, (The Netherlands). E-mail: [email protected] Metal-coordination compounds displaying metal-ligand exchange rates comparable to cell-division processes, often appear to be highly active as anticancer agents. The involved metal compounds are usually those of Pt and Ru, but also other metals like Sn, Au, Ti and Rh have been shown to yield active compounds. The compound cisdiamminedichloridoplatinum(II), known since 1845, abbreviated as cisplatin, and several newer derivative Pt compounds are known to interact with DNA. Mechanistic knowledge has led to strategies for the design of new metal-containing drugs. In our work special attention has been given to bifunctional DNA binding systems, to generate new compounds. Detailed studies of the binding (i.e. kinetics and structures) of known and new metal coordination compounds to nucleic acids, could first of all lead to a better understanding of the mechanism of action; however, such studies may also result in developments of new drugs, with special DNA binding [1]. In the lecture, important chemistry facts that have led to a major improvement of our insight into the mechanism of action will be presented. More recently, we have also been studying other metals that bind to DNA, like Cu and Ru [2], and with a special focus on the multifunctional binding of such compounds. This work originated from our studies where a fluorescent group was attached, to follow the processing of the compounds in real time, while in the cells [3]. Finally, combining our work on Cu-DNA binding [4] with that of platinum, and ruthenium [5] has resulted in totally new compounds that have been used for both DNA cutting [6] and for developing new anticancer chemistry [7]. [1] J. Reedijk; Proc. Natl. Acad. Sci. U. S. A., 2003, 100, 3611-6. [2] K. van der Schilden, F. Garcia, H. Kooijman, A.L. Spek, J.G. Haasnoot and J. Reedijk; Angew. Chem.-Int. Edit., 2004, 43, 5668-5670. [3] G.V. Kalayda, B.A.J. Jansen, P. Wielaard, H.J. Tanke and J. Reedijk; J. Biol. Inorg. Chem., 2005, 10, 305315. [4] P.U. Maheswari, S. Roy, H. den Dulk, S. Barends, G. van Wezel, B. Kozlevcar, P. Gamez and J. Reedijk; J. Am. Chem. Soc., 2006, 128, 710-711. [5] S. van der Steen, P. de Hoog, K.van der Schilden, P. Gamez, M. Pitié, R. Kiss and J.Reedijk, Chem. Commun., 2010, 46, 3568 - 3570. [6] S. Özalp-Yaman, P. de Hoog, G. Amadei, M. Pitié, P. Gamez, J. Dewelle, T. Mijatovic, B. Meunier, R. Kiss and J. Reedijk; Chem. Eur. J., 2008, 14, 3418-3426. [7] J. Reedijk; Eur. J. Inorg. Chem. 2009, 1303-1312.

Multinitrogen macrocyclic schiff base ligands containing phenoxide groups have received special attention in the past decades because of their versatile coordination behaviors and biological activities. Researches show that this kind of macrocyclic complexes have good DNA binding and cleavage biological properties. In our previous work, we investigated the DNA binding and cleavage ability of some homodinuclear mutinitrogen macrocyclic complexes which cleavage DNA via intercalate mode with higher binding constants to DNA [1]. Recently, our interest has been directed towards the study of the unsymmetrical macrocycles. Here, we report the synthesis of new unsymmetrical macrocyclic complexes by cyclo condensation of N,N’-bis(3-formyl-5-methylsalicylidene) aliphatic/aromatic diimine with 1,2-Bis(aminooxy)ethane in the presence of the metal ions. These complexes are characterized by elemental analyses, IR spectra and X-ray determinations. Absorption spectroscopic investigation reveals that all the complexes show hypochromism and a red shift (bathochromism) of the absorption band. The results shows that the aromatic diimine containing macrocyclic binuclear complexes [M2L] display better binding propensity (5.4 × 104 to 17.9 × 104 M-1) with CT DNA than aliphatic diimine containing macrocyclic binuclear complexes (1.4 × 104 to 4.2 × 104 M-1). Fluorescence spectroscopy shows that the complex can displace ethidium bromide. The results shows that the naphthalene diimine containing macrocyclic binuclear complexes [M2L] display better relative binding propensity (12.2 × 105 to 15.4 × 105 M-1) with CT DNA than propylene diimine containing macrocyclic binuclear complexes (0.31 × 105 to 0.62 × 105 M-1). The agarose gel electrophoresis studies of plasmid pBR322 DNA show that macrocyclic binuclear copper(II) complexes/ mercaptoethanol system remarkably degrading the supercoiled pBR322DNA by oxidative (O2 –dependent pathway) cleavage mechanism using the singlet oxygen as the reactive species. In the presence of H2O2, the macrocyclic binuclear nickel(II) and zinc(II) complexes cleaves the DNA by hydrolytic mechanism.

[1] S. Anbu, M. Kandaswamy, P. Suthakaran, V. Murugan, B. Varghese, J. Inorg. Biochem., 2009, 103, 401-410. [2] S. Anbu, M. Kandaswamy, B. Varghese, Dalton Transactions, 2010, 39, 3823-3832.

Keywords: Unsymmetrical Macrocycles; Binuclear complexes; DNA binding and cleavage studies

metal

Keywords: platinum; ruthenium; anticancer; DNA

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Synthesis of new unsymmetrical macrocyclic binuclear copper(II), nickel(II) and zinc(II) complexes: Structural, DNA binding and DNA cleavage studies. Muthusamy Kandaswamy and Sellamuthu Anbu Department of Inorganic Chemistry, University of Madras, Chennai, (India). E-mail: [email protected]

Microsymposia MS.D2.C.08

MS.D2.C.09

Formation and Reactivity of a Mononuclear Copper(II) End-on Superoxo Complex Shinobu Itoh, Yuki Kobayashi, Kei Okubo, Nobutaka Fujieda, Hideki Sugimoto, Shunichi Fukuzumi, Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University (Japan). E-mail: shinobu@ mls.eng.osaka-u.ac.jp

Metallomacrocycles as ion-gated molecular devices Jim A Thomas,b Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, UK, E-mail: [email protected]

Mononuclear copper(II) superoxo complexes have attracted much recent attention due to their strong relevance to the reactive intermediate involved in the catalytic reactions of copper monooxygenases.[1] These enzymes catalyze hydroxylation reaction of aliphatic substrates by molecular oxygen at the simple mononuclear copper reaction center. To date, both side-on and end-on superoxo copper(II) model complexes have been reported to provide important insights into the structure and physicochemical properties of the reactive intermediate involved in the copper monooxygenases.[1] One of the most successful accomplishments in the synthetic modelling studies is the first crystal structure determination of the mononuclear copper(II) end-on superoxo complex using sterically demanding tren [tris(2-aminoethyl)amine] derivative, TMG3tren (tris(2-(N-tetra- methylguanidyl)ethyl)amine), as the supporting ligand.[1] HIPT3tren is also a tren derivate carrying bulky hydrophobic HIPT (hexaisopropylterphenyl) substituents on the nitrogen donor atoms. This compound can stabilize mononuclear transition-metal complexes by preventing dimerization using steric repulsion, whereas it still provides a space above the metal center for substrate binding. In this study, we have examined the ligand effects of HIPT3tren on copper(I)dioxygen chemistry to get more insight into the dioxygen activation at a mononuclear copper reaction center.

Ruthenium(II) polypyridyl complexes that interact reversibly with DNA can display high binding affinities and selectivities [1,2] as well as interesting photophysical properties [3]. Although such complexes offer potential as in cellulo probes for luminescence microscopy, poor cellular uptake by live cells restricts the use of such molecules. In recent studies we have shown that complexes such as 1 and 2 are taken up by both live eukaryotic and prokaryotic cells where they bind to nuclear DNA as evident by both luminescence and transmission electron microscopy[4] suggesting they may find use as cellular specific imaging agents and/or therapeutics [5]. A distinctive property of 2 - revealed by in vitro and in cellulo studies - is that high affinity binding of specific DNA structures leads to distinctive emission signatures [4,6]. Herein we present progress in this area, including structural studies aimed at delineating the cause of this complex’s structural binding preferences [7].

[1] (a) C. Metcalfe, J. A. Thomas, Chem. Soc. Rev. 2003, 32, 214. (b) M. R. Gill, J. A. Thomas, Chem. Soc. Rev., 2012, 41, 3179. [2] P. Waywell, V. Gonzalez, M. R. Gill, H. A. Adams, A. J. H. M. Meijer, M. P. Williamson, J. A. Thomas, Chem Eur J, 2010, 16, 2407.[3] (a) S. P. Foxon, T. Phillips, M. R. Gill, M. Towrie, A. W. Parker, M. Webb, J. A. Thomas, Angew. Chem. Int. Ed., 2007, 46, 3686-3689. (b) V. G. Gonzalez, T. Wilson, I. Kurihara, A. Imai, J. A. Thomas, J. Otsuki, Chem. Commun. 2008, 168. [4] M. R. Gill, J. Garcia-Lara, S. J. Foster, C. G. W. Smythe, G. Battaglia, J. A. Thomas, Nat Chem, 2009, 1, 662-667. [5] M. R. Gill, H. Derat, C. G. W. Smythe, G. Battaglia, J. A. Thomas, ChemBioChem, 2011, 12, 877. [6] T. Wilson, M. P. Williamson, J. A. Thomas, Org. Biomol. Chem., 2010, 8, 2717. [7] T. Wilson, P. J. Costa, V. Felix, M. P. Williamson, J. A. Thomas, in preparation.

Keywords: Ruthenium, DNA, imaging

Figure 1. Expected structure of end-on superoxo copper(II) complex 1 supported by HIPT3tren ligand.

Reaction of a copper(I) complex supported by HIPT3tren and O2 gave a mononuclear copper(II) end-on superoxo complex 1, on which spectroscopic (UV/vis, resonance Raman, ESR, and 1H-NMR) and DFT studies have been performed. The O2-binding process as well as the reaction toward external substrates has also been investigated kinetically to demonstrate a unique behavior of the copper(II) end-on superoxo complex, that may be due to the existence of the hydrophobic core around the copper coordination sphere created by the HIPT3tren ligand. [1] S. Itoh, in Copper-Oxygen Chemistry, Vol. 4 (Eds.: K. D. Karlin, S. Itoh), John Wiley & Sons, Hoboken, 2011, pp. 225-282.

Keywords: Copper, End-on Superoxo Complex, Reactivity

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MS.D2.C.10 Towards understanding the biological activity of coordination compounds with imidazole derivatives N. Barba-Behrensa, Soledad Betanzos-Lara,a I. Gracia-Mora,a I. Alfaro-Fuentes,a M. Bernal-Uruchurtub, R. Contreras,c A. FloresParra,b,c aDepartamento de Química Inorgánica, Facultad de Química, Universidad Nacional Autónoma de México, C.U., Coyoacán, México, D.F., 04510, México, bCentro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos (México), c Departamento de Química, Centro de Investigación y de Estudios Avanzados (México). Email: [email protected] We have been interested to study the coordination ability of biological active molecules towards transition metal ions and the structural properties of these coordination compounds. On the other hand, we have been investigating their antineoplasic and antimicrobial activity. Along these lines, synergistic effects on transition metal coordination compounds of imidazole and azole derivatives have been probed. The complexes hence obtained display promising therapeutic

Microsymposia

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potential as cytotoxic, antiviral, antibacterial, antineoplastic and/or antiamoebic agents.[1,2] In this work we present a series of cobalt(II) copper(II) and zinc(II) coordination compounds with imidazole and nitroimidazole derivatives, in an effort to combine the chemotherapeutic properties of the parental drug with the DNA binding (or other related) capacity of the central metal atom. The complexes were fully characterised by means of UV-Vis-NIR and EPR spectrophotometry, elemental analysis, mass spectrometry and X-ray diffraction in selected cases. It was evaluated the biological activity of these new complexes: antimicrobial and anticancer activities in order to establish a plausible mechanism of action.

[Zn(clotri)Cl2] Acknowledgements Financial support from DGAPA-UNAM IN212210 and Conacyt 60894-CB are acknowledged. [1] H. López-Sandoval H., M. Enrique Londoño-Lemos , R. Garza-Velasco, I. Poblano-Meléndez , P. Granada-Macías, I. Gracia-Mora, N. Barba-Behrens, J. Inorg. Biochem. 102 (2008) 1267. [2] O. Sánchez-Guadarrama, H. LópezSandoval, F. Sánchez-Bartéz, I. Gracia-Mora, H- Höpfl, N. Barba-Behrens, J. Inorg. Biochem., 103 (2009) 1204-1213.

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9 - 13 September 2012

Microsymposia MS.D3.KN1 Metalloprotein Design: New Zn Hydrolyases Using Varying Protein Scaffolds Pecoraro V.L, Zastrow M, Peacock A.F.A, Cangelosi V, Mocny C, Department of Chemistry, University of Michigan, Ann Arbor, MI, USA 48109-1055 De Novo Protein Design has recently been shown to be a powerful technique for modelling the active sites of Zn metalloproteins. Using this technique one may not only provide a synthetic construct which precisely mimics the first coordination sphere of a known metalloenzyme site, one may also develop a catalytic center that is embedded within a hydrophobic protein pocket and which has its coordination chemistry influenced by second coordination sphere ligands. In this presentation, we will discuss how to prepare a mixed Hg(II),Zn(II) protein that is capable of efficient, multiturnover hydrolysis of nitrophenylacetate in aqueous solution over the pH range 7.5 to 9.5. We also show this construct is capable of CO2 hydration. The Zn(II) catalytic center is structurally homolgous with those found in carbonic anhydrases and matrix metalloproteinases. We will also demonstrate how a structural site, in this case Hg(II), stabilizes the protein and leads to slightly enhanced catalytic activity. In the presented studies, we will discuss how to insert asymmetry into the designed construct either by using strategies to generate heterotrimeric 3-stranded coiled coils or through the preparation of 3-stranded bundles with tris histidine metal binding sites. Keywords: Protein design, Zn Enzymes, Metallohydrolases

MS.D3.KN2 Bionorganic Chemistry of alpha-Synuclein: Relevance to Parkinson Disease Claudio O. Fernández,a Andres Binolfi,a Valentina Torres-Monserrat,a Liliana Quintanar,b Christian Griesinger,c aInstituto de Biología Molecular y Celular de Rosario and Universidad Nacional de Rosario, Rosario (Argentina). bCentro de Investigación y de Estudios Avanzados, D.F. (México). cMax Planck Institute for Biophysical Chemistry, Göttingen (Germany). E-mail: [email protected] Alpha-synuclein (AS) aggregation is associated to neurodegeneration in Parkinson´s disease (PD). At the same time, alterations in metal ion homeostasis may play a pivotal role in the progression of AS amyloid assembly and the onset of PD. Elucidation of the structural basis directing AS-metal interactions and their effect on AS aggregation constitutes a key step towards understanding the role of metal ions in AS amyloid formation and neurodegeneration. This presentation provides a comprehensive view of recent advances made by our group in the bioinorganic chemistry of AS amyloid diseases [1-4]. A hierarchy in AS-metal ion interactions has been established: while divalent metal ions interact at a non-specific, low-affinity binding interface at the C-terminus of AS, copper binds with high affinity at the N-terminal region and it is the most effective metal ion in accelerating AS filament assembly. The strong link between metal binding specificity and its impact on aggregation will be discussed on a mechanistic basis. A detailed description of the structural features and coordination environments of copper to AS will be presented and discussed in the context of oxidative cellular events that might lead to the development of PD. Overall, our research findings support the notion that perturbations in copper metabolism may be a common upstream event in the pathogenesis of neurodegenerative processes.

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[1] R.M. Rasia, C.W. Bertoncini, D. Marsh, W. Hoyer, D. Cherny, M. Zweckstetter, C. Griesinger, T.M. Jovin, C.O. Fernández, Proc. Natl. Acad. Sci. U S A,, 2005, 102, 4294-4299. [2] Binolfi A, Rasia RM, Bertoncini CW, Ceolin M, Zweckstetter M, Griesinger C, Jovin TM, Fernandez CO., J Am Chem Soc., 2006, 128, 9893-9901. [3] A. Binolfi, G.R. Lamberto, R. Duran, L. Quintanar, C.W. Bertoncini, J.M. Souza, C. Cerveñansky, M. Zweckstetter, C. Griesinger, C.O. Fernández, J. Am. Chem. Soc., 2008, 130,11801-11812. [4] A. Binolfi, A.A. Valiente-Gabioud, R. Duran, M. Zweckstetter, C. Griesinger, C.O. Fernández, J. Am. Chem. Soc., 2011, 133, 194-196.

Keywords: Amyloid, oxidative-damage, neurodegeneration

MS.D3.I1 Biomimetic Metal-Oxygen Intermediates in Dioxygen Activation Chemistry Wonwoo Nam,a aDepartment of Bioinspired Science, Department of Chemistry and Nano Science, Ewha Womans University (Korea). E-mail: [email protected] Dioxygen is essential in life processes, and enzymes activate dioxygen to carry out a variety of biological reactions. One primary goal in biomimetic research is to elucidate structures of reactive intermediates and mechanistic details of dioxygen activation and oxygenation reactions occurring at the active sites of enzymes, by utilizing synthetic metal-oxygen complexes. A growing class of metaloxygen complexes, such as metal–superoxo, –peroxo, –hydroperoxo, and –oxo species, have been isolated, characterized spectroscopically, and investigated in various oxygenation reactions. During the past decade, we have been studying the chemical and physical properties of various reactive intermediates in oxygenation reactions, such as highvalent iron(IV)- and manganes(V)-oxo complexes of heme and nonheme ligands in oxo-transfer and C-H activation reactions, non-heme metal-peroxo complexes in nucleophilic reactions, and non-heme metal-superoxo complexes in electrophilic reactions. The effects of supporting and axial ligands on structural and spectroscopic properties and reactivities of metal-oxygen adducts have been extensively investigated as well. In this presentation, I will present our recent results on the reactivities of various metal-oxygen intermediates in electrophilic and nucleophilic oxidation reactions. The synthesis and structural and spectroscopic characterization of mononuclear nonheme metal-dioxygen intermediates will be discussed as well.

MS.D3.I2 Native ESI and Ion Mobility Mass Spectrometry studies on the zinc sensor SmtB Claudia A. Blindauer,a Frances D.L. Kondrat,a,b James Scrivens,b a Department of Chemistry, University of Warwick, Coventry, UK. a School of Life Sciences, University of Warwick, Coventry, UK. E-mail: [email protected] Reliable determination of the stoichiometry of non-covalent complexes is paramount for an understanding of biomolecular processes. This is also true for metalloproteins. The majority of methods for the determination of metal:protein binding stioichiometries relies on an acccurate knowledge of protein concentration, which in practice is more problematic than commonly appreciated. The zinc sensor protein SmtB [1] will be presented as a case study highlighting these issues, with a focus on the capabilities of native ESIMS, combined with Inductively-Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), to study the speciation of metalloproteins. ESI-MS does not only provide rapid access to the identity of major species, but can also be employed to monitor metal-transfer reactions in real time [2,3].

Microsymposia

We show that SmtB purified from bacterial cell lysate contains predominantly four zinc ions per dimer, and that zinc removal by EDTA generates all possible monomeric and dimeric species, with no clear preference for any particular intermediates. Like in the solution phase, zinc ions stabilise the dimer in the gas phase. Ion-mobility mass spectrometry studies for the various species demonstrate that zinc has a profound effect on the stability of the protein fold. The removal of one zinc ion has only small effects on conformational equilibria, but dimeric species with 3-0 zinc ions are increasingly more flexible, whereas monomeric species show a pronounced tendency to unfold. Acknowlegements: We thank the EPSRC and ACTF (studentship to F.K.), Advantage West Midlands and the European Regional Development Fund (Birmingham Science City) for support, and Prof. Nigel Robinson for the donation of an expression construct for SmtB.

[1] T. Tron, in Encyclopedia of Metalloproteins, Kretsinger, RH, Uversky, VN, Permyakov, EA. (Eds.) Springer, in press. [2] E. Solomon, U. Sundaram, T. Machonkin, Chem. Rev., 1996, 96, 2563-2605. [3] V. Balland, C. Hureau, A. Cusano, Y. Liu, T. Tron, B, Limoges, Chem. Eu. J., 2008, 14, 7186-92. [4] V. Robert, Y. Mekmouche, P. Rousselot Pailley, T. Tron, Curr. Genomics, 2011, 12, 123-129. [5] A. Simaan, Y. Mekmouche, C. Herrero, P. Moreno, A. Aukauloo, J. Delaire, M. Réglier, T. Tron. Chem. Eu. J., 2011, 17, 11743-11746.

[1] A. P. Morby, J. S. Turner, J. W. Huckle and N. J. Robinson, Nucleic Acids Res., 1993, 21, 921-925. [2] O. I. Leszczyszyn, C. D. Evans, S. E. Keiper, G. Z. L. Warren and C. A. Blindauer, Inorg. Chim. Acta, 2007, 360, 3-13. [3] O. I. Leszczyszyn and C. A. Blindauer, Phys. Chem. Chem. Phys., 2010, 12, 1340813418.

Keywords: Copper enzyme, photoinduced ET, dioxygen

Keywords: zinc sensor, ESI-MS, metal trafficking

Spectroscopic insights into the smallest possible metal-thiolate cluster Eva Freisinger, Institute of Inorganic Chemistry, University of Zurich, Zurich (Switzerland). E-mail: [email protected]

MS.D3.I3 Photoinduced Multi-Electron Transfer to a Multicopper Oxidase Tron Thierry, Npetgat Eloine, Schneider Ludovic, Simaan A. Jalila, Mekmouche Yasmina, Robert Viviane, Rousselot Pailley Pierre, Réglier Marius, ISM2 UMR 7313, CNRS, Aix-Marseille Université 13397 Marseille cedex 20, France. E-mail: [email protected] Laccases are very well known biocatalysts with great robustness, high oxidation power and substrate versatility (among other properties) [1]. Laccases contain a unique set of copper ions made of one each of the three types of biorelevant copper sites: type 1 (T1), type 2 (T2) and a binuclear type 3 (T3), and couple dioxygen reduction to the oxidation of substrates, either organic or metal ion [2]. They belong to the Blue Copper Binding Domain (BCBD) family of proteins in which the archetypal members are the plant or bacterial electron transfer protein cupredoxins (CUP). In this family, function is modulated by the number of CUP domains, the number and type copper atoms and the fusion to non metalled domains. Taking natural plasticity within the BCBD family as a source of inspiration for the engineering of laccases, we aim at shaping new catalysts using the enzyme as a platform functionalized with “plug-ins” [3, 4]. One of our targets is to develop robust systems where light absorption triggers electron transfer events that subsequently lead to the activation of a catalytic centre. The efficient accumulation of multi charges at the catalytic unit is a challenging issue. We report here on the light driven four-electron reduction of a laccase that ultimately converts dioxygen into water using ruthenium(II) polypyridine or porphyrin type chromophores and a sacrificial electron donor.

MS.D3.C.01

In metal clusters metal ions are coordinated both by terminal and bridging ligands. Metallothioneins (MTs), small cysteine-rich proteins involved among others in the homeostasis and detoxification of metal ions with the electron configuration d10, form metal-thiolate clusters of the Werner-type, i.e. clusters without direct bonds between neighbouring metal ions. The variety of metal-thiolate clusters observed in MTs so far is rather limited. For the divalent metal ions, i.e. essential ZnII and toxic CdII, only two basic structures were known: the M4Cys11 and the M3Cys9 cluster. Recently, we were able to describe a third form, M2Cys6, found in a plant MT [1,2]. Featuring just two metal ions, this cluster represents the smallest possible metal-thiolate cluster and was previously only known from yeast transcription factors [3]. The spectroscopic characterization of this cluster including its solution structure determined by NMR spectroscopy will be presented providing insights into specific metal ion coordination properties and possible metallation pathways. Results will be compared to the spectroscopic properties of the clusters in the yeast transcription factors and the larger metal-thiolate clusters from other MT forms. [1] E. A. Peroza, R. Schmucki, P. Güntert, E. Freisinger, O. Zerbe, J. Mol. Biol., 2009, 387, 207-218. [2] J. Loebus, E. A. Peroza, N. Blüthgen, T. Fox, W. Meyer-Klaucke, O. Zerbe, E. Freisinger, J. Biol. Inorg. Chem., 2011, 16, 683-694. [3] R. Marmorstein, M. Carey, M. Ptashne, S. C. Harrison, Nature, 1992, 356, 408-414.

Keywords: metal-thiolate cluster, metallothionein, spectroscopy

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Reduction of copper centres is demonstrated by UV/VIS and ESR spectroscopies. The fully reduced enzyme is able in turn to reduce dioxygen into water[5].

Microsymposia MS.D3.C.02 A Novel Alcohol Dehydrogenase from N2-fixing Bacteria Peter Kroneck,a Martha E. Sosa Torres,b aFachbereich Biologie, University of Konstanz, Konstanz, (Germany). bFacultad de Quimica, Universidad Nacional Autonoma de Mexico, Mexico D.F. (Mexico). E-mail: [email protected] The activation of kinetically inert molecules, such as dinitrogen (N2), nitrous oxide (N2O), or dioxygen (O2), usually requires a sophisticated catalytic machinery, with unique transition metal centers at the active site [1], [2]. To cleave the N,N triple bond of N2, up to 16 ATP molecules are needed by nitrogen-fixing bacteria to produce two molecules of NH3, and one molecule of H2. In the case of Gluconacetobacter diazotrophicus, a set of dehydrogenases is overexpressed when grown under nitrogen-fixing energy demanding conditions. Among these is the PQQ-dependent enzyme alcohol dehydrogenase (ADH) which is located in the cytoplasmic membrane of the microorganism. ADH (consisting of subunits I and II) is oriented towards the periplasm and transfers electrons to membrane-bound quinones. Ga. diazotrophicus can oxidize ethanol to acetic acid in two consecutive reactions, using ADH and a molybdenum-dependent aldehyde oxidase as catalysts. In this contribution, biochemical, spectroscopic, and structural properties of this metabolically important catalyst will be presented. ADH of Ga. diazotrophicus is a novel multi-heme enzyme, with one PQQ, four c-type cytochromes, and one [2Fe-2S] cluster as documented by low temperature EPR spectroscopy [3]. The oxidation-reduction potentials Em (pH 6.0/SHE) of the four heme iron centers range from - 64 mV to + 210 mV (spectroelectrochemistry), compared to - 250 mV for the [2Fe-2S] cluster and - 210 mV for the PQQ/PQQH2 couple (EPR spectroscopy). A structural model for the membrane-bound ADH of Ga. diazotrophicus will be proposed showing the intra- and intermolecular electron pathways. Subunit I binds the PQQ cofactor, the [2Fe-2S] cluster, and one c-type cytochrome, subunit II harbours three c-type cytochromes. In conclusion, the novel multi-component alcohol dehydrogenase provides a perfect electron transfer route to the quinonens located in the cytoplasmic membrane which is key for an efficient energy conserving system required by the nitrogen-fixing organism. [1] M. Rudolf, P.M.H. Kroneck, Met. Ions Biol. Sys., 2005, 43, 76-103. [2] A. Pomowski, W.G. Zumft, P.M.H. Kroneck, O. Einsle, Nature, 2011, 477, 234-237. [3] S. Gomez-Manzo, A. Solana-Peralta, J.P. Saucedo-Vazques, J.E. Escamilla-Marvan, P.M.H. Kroneck, M.E. Sosa-Torres, Biochemistry, 2010, 49, 2409-2415.

Keywords: metalloenzyme, catalysis, spectroscopy

MS.D3.C.03 An Iron Cysteinato Complex as a Functional Model for the Cysteine Dioxygenase Christian Limberg, Madleen Sallmann, Inke Siewert, Lea Fohlmeister, Christina Knispel, Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Straße 2, 12489 Berlin (Germany). E-mail: christian. [email protected] The cysteine dioxygenase (CDO) is a non-heme iron proteine that catalyzes the oxygenation of cysteine with molecular oxygen to yield cysteine sulfinic acid, needed for the assembly of central metabolites in the human organism. While the functions of many oxygenating iron enzymes could be successfully imitated within the last decades using molecular model compounds,[1] there are hardly any reports in

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the literature[2] to date on biomimetic models for the CDO, whose structure has been known since 2006 (the structure of the active site after substrate binding[3] is shown in the Scheme, right hand side). Obvious problems are the formation of FeIII-O-FeIII compounds instead of oxygenated sulfur-containing species, S-overoxidation and S-S bond formation. Recently, we have been able to develop the complex [TpMe,PhFeCysOEt], 1, which represents an excellent structural and functional replicate of the CDO: 1) The TpMe,Ph ligand excellently mimics the (His)3-coordination sphere of the FeII center (see Scheme), and the cysteine substrate is only slightly modified by esterification; 2) Treatment with O2 leads to dioxygenase activity, as confirmed inter alia by isotopic labeling experiments.[4] 1 therefore represents the hitherto most realistic model for the active site of the cysteine dioxygenase and thus an interesting source for the elucidation of structural information on the product complex within the CDO catalytic cycle as well as corresponding mechanistic details.

[1] M. Costas, M. P. Mehn, M. P. Jensen, L. Que, Jr., Chem. Rev. 2004, 465-465; I. Siewert, C. Limberg, Chem. Eur. J. 2009, 15, 10316-10328; S. Friedle, E. Reisner, S. J. Lippard, Chem. Soc. Rev. 2010, 39, 2768-2779. [2] Y. Jiang, L. R. Widger, G. D. Kasper, M. A. Siegler, D. P. Goldberg, J. Am. Chem. Soc. 2010, 132, 12214-12215; Y. M. Badiei, M. A. Siegler, D. P. Goldberg, J. Am. Chem. Soc. 2011, 133, 1274-1277; A. R. McDonald, M. R. Bukowski, E. R. Farquhar, T. A. Jackson, K. D. Koehntop, M. Sook Seo, R. F. De Hont, A. Stubna, J. A. Halfen, E. Münck, W. Nam, L. Que, Jr., J. Am. Chem. Soc. 2010, 132, 17118-17129. [3] S. Ye, X. Wu, L. Wei, D. Tang, P. Sun, M. Bartlam, Z. Rao, J. Biol. Chem. 2007, 282, 3391. [4] M. Sallmann, I. Siewert, L. Fohlmeister, C. Limberg, C. Knispel, Angew. Chem. Int. Ed. 2011, 51, 2234–2237.

Keywords: enzyme models, iron, S-oxygenation

MS.D3.C.04 Chiral Lanthanide Complexes as Luminescent Probes for Proteins Nicholas H. Evans,a David Parker,a aDepartment of Chemistry, Durham University, South Road, Durham, DH1 3HE (UK). E‑mail: nicholas. [email protected] Probes of the chiral environment, based on optical signalling, are rare. Emissive lanthanide complexes are attractive candidates,

Microsymposia as they are pure “spherical” emitters (obviating problems associated with anisotropy) and are known to produce large circularly polarised luminescence (CPL) responses.[1] Here we present the design, synthesis and study of lanthanide complexes that could act as selective chiral probes for proteins.[2] They are based on a 1, 4, 7-triazacyclonane macrocycle decorated with sensitising pyridyl groups enabling coordination of appropriate lanthanides cations (Eu, Tb).[3] Critical features such as configurational stability, water solubility and requisite photophysical properties have been considered and are built into the design of the complexes. By varying the functionality on the aromatic ring, the discrimination of a range of proteins and selected chiral anions in biological media by the complexes is being scrutinized by CPL spectroscopy.

Figure 1 ORTEP diagram of cation part of 1a

[1] G. Muller, Dalton Trans, 2009, 9692-9707. [2] For representative examples of lanthanide complexes acting as selective CPL probes for proteins see: (a) C. P. Montgomery, E. J. New, D. Parker, R. D. Peacock, Chem Commun, 2008, 4261-4263; (b) R. Carr, L. Di Bari, S. Lo Piano, D. Parker, R. D. Peacock, J. M. Sanderson, Dalton Trans, 2012, DOI: 10.1039/C2DT30143A. [3] For an example of a triazacyclonane-based lanthanide complex, see: J. W. Walton, L. Di Bari, D. Parker, G. Pescitelli, H. Puschmann, D. S. Yufit, Chem Commun, 2011, 47, 12289-12291.

Figure 2 Dioxygen activation of the diiron complex

MS.D3.C.05 Dioxygen Activation of Diiron Complex with CarboxylateContaining Dinucleating Ligand BPG2E Masahito Kodera,a Tomohiro Yasunaga,a Yuka Kawahara,a Yutaka Hitomia, Takashi Nomurab, Takashi Ogurab, Yoshio Kobayashi,c a Department of Molecular Chemistry and Biochemistry, Doshisha University, Kyoto, (Japan). bUniversity of Hyogo, Hyogo, (Japan). c The Institute for Physical and Chemical Research (RIKEN), Saitama, (Japan). E-mail: [email protected] A carboxylate-containing dinucleating ligand, 1,2-bis[2-(N-2pyridylmethyl-N-glycinylmethyl)-6-pyridyl]ethane (H2BPG2E) was synthesized to mimic the carboxylate-rich coordination environment of the nonheme diiron enzymes. H2BPG2E forms m-oxodiaquadiiron(III) complexes [Fe2(m-O)(H2O)2(BPG2E)]X2 (X = ClO4, 1a and OTf, 1b). The complexes are structurally characterized by X-ray analysis (Fig. 1). The coordinated water molecules take syn-configuration each other. The complex 1b reacts with an excess amount of H2O2 at low temperature in the presence of Et3N in MeCN to generate a dark green species exhibiting a broad absorption band at 500-600 nm, assignable to a peroxo-to-iron(III) LMCT band, indicating that m-oxom-peroxodi- iron(III) complex is generated. The peroxo complex is further characterized by the CSI MS and resonance Raman spectra. The peroxo complex precipitated as purple solid upon addition of an excess amount of Et2O at low temperature. The Mössbauer spectra of the isolated solid clearly show that the peroxodiiron(III) is converted to trioxodiiron(IV)[1] with increasing the temperature. The conversion of peroxodiiron(III) to trioxodiiron(IV) complex is a very important elementary reaction in a dioxygen activation via a O-O bond scission (Fig. 2). Moreover, 1b efficiently catalyzes the epoxidation of alkene with H2O2 as an oxidant. This is the first example for efficient oxygenation of external substrate with H2O2 catalyzed by diiron complex with carboxylate-rich ligand.

[1] M. Kodera; M. Itoh, Angew. Chem. Int. Ed., 2005, 44, 7104.

Keywords: nonheme diiron carboxylate-rich ligand

enzyme,

dioxygen

activation,

MS.D3.C.06 Metal-Coordinated Ligand Radicals and their Reactivity Rabindranath Mukherjee, Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016 and Indian Institute of Science Education and Research Kolkata, Mohanpur Campus, Mohanpur 741 252 (India). E-mail: [email protected]; [email protected] The interaction of transition-metal ions with organic radicals is a subject that currently receives much attention. One of the driving forces of this research direction is the realization that such systems exist in the active sites of metalloproteins. The mononuclear copper enzyme Galactose Oxidase (GOase) catalyzes the selective oxidation of primary alcohols to aldehydes by dioxygen, which is reduced to hydrogen peroxide. In addition to the copper atom, the active site of GOase contains a copper-bound, cysteine-linked tyrosine residue that operates as an additional one-electron cofactor. The two cofactors operate in tandem to accomplish substrate-oxidizing and dioxygenreducing half-cell reactions. Apart from bioinorganic perspectives an understanding of the nature of magnetic interaction between the ligand radical(s) coordinated to transition and non-transition metal ions is of fundamental importance. In recent years the determination of molecular structure, investigating the magnetic, spectral and redox properties, and correct assignment of electronic structure of metal complexes of 2-anilino4,6-di-tert-butylphenol-derived ligands in their di-deprotonated form have drawn the attention of inorganic chemists due to non-innocent (redox-active) nature of such ligands [1]. As a part of our continuing efforts to understand the properties of metal-coordinated ligand radical species from the standpoint of modeling GOase activity [2,3], we have directed our attention to designing new ligands of 2-anilino-4,6-ditert-butylphenol appended with a benzylthioether substituent in the ortho position of the N-aryl group or with a 2-arylazo group, and to investigate their coordination behavior towards transition metal ions.

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Keywords: chirality, lanthanide, luminescence

Microsymposia In this presentation, the synthesis, molecular structure (X-ray), and electronic structure (spectroscopic, magnetic, DFT calculations) of complexes of abovementioned non-innocent tailor-made organic ligands and radical-driven reactivity aspects, from general interest and also from the standpoint of the structure and properties of their counterparts in natural systems, will be discussed. [1] A. Mukherjee, R. Mukherjee, Indian J. Chem, 2011, 50A, 484-490 (Special Issue on Bioinorganic Chemistry; R. Mukherjee is one of the editors of this issue). [2] A. Mukherjee, F. Lloret, R. Mukherjee, Inorg. Chem, 2008, 47, 44714480. [3] A. Mukherjee, F. Lloret, R. Mukherjee, Eur. J. Inorg. Chem. 2010, 1032-1042.

Keywords: metal-coordinated ligand radicals, molecular and electronic structure, ligand radical-driven reactivity

MS.D3.C.07 New targets demand designed “bullets”: inhibition of transcription by cage complexes Yan Voloshina, Valentin Novikova, Oleg Varzatskiib, Valentina Negrutskac, Yurii Bubnova, Igor Dubeyc. aNesmeyanov Institute of Organoelement Compounds RAS, Moscow (Russia). bVernadskii Institute of General and Inorganic Chemistry NASU, Kiev (Ukraine). c Institute of Molecular Biology and Genetics NASU, Kiev (Ukraine). E-mail: [email protected] The recent concept of “allosteric drugs” implies the existence of the hidden allosteric sites, offering the opportunity to develop the inhibitors for biological targets. These sites are not known, and their choice depends on our ability to create the artificial molecules that are topologically complementary to them. The other new methodology, which is the targeting of protein – protein interactions, also promises the broad range of medical applications. The extensive surface and more diverse geometry of the cage compounds with an encapsulated metal ion (clathrochelates) are suitable for targeting both the allosteric sites and the macromolecular interfaces. These compounds show incredible stability even at the most severe conditions, and their macrobicyclic molecules can easily be functionalized using up to eight substituents; they demonstrate good ADMET properties, such as sufficient membrane permeability and low toxicity. We report the first example of an efficient transcription inhibition by the iron(II) clathrochelates in a model in vitro system based on T7 RNA polymerase (T7 RNAP). The in vitro testing in the T7 RNAP transcription assay revealed the structure- and concentrationdependent inhibition of the transcription by most of these compounds in the concentration range of 20 – 30 mM, and an increase in their concentrations resulted in a decrease in the amount of the RNA synthesized. Moreover, the monoribbed-functionalized iron(II) clathrochelates (Scheme) proved to be the highly efficient nanomolar inhibitors of this transcription. The binding mode of the clathrochelates to the T7 RNAP was studied by the molecular docking. The inhibitor molecule is located in the transcriptional “bubble” and involved in the intermolecular contacts with protein residues as well as with DNA and RNA: their surfaces form the framework of the pocket for the inhibitor’s binding.

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The possibility to “build” the structure of an inhibitor from a single center in eight different directions, combined with the plethora of functionalizing groups available for its modification, paves the way for the design of the clathrochelate-based inhibitors (so-called “topological drugs” as the prospective antiviral and anticancer drug candidates), whose shapes closely matches the macromolecular surfaces of a very complex topology, including protein – protein and protein – DNA interaction interfaces. This study was supported by RFBR–SFFR 11-03-90458 / F40.4/078. Keywords: drug design, inhibitors, cage compounds

MS.D3.C.08 Profiling the metal site of a Cu-enzyme through far-IR fingerprint (700-50 cm-1) D. Berthomieu1, L. Marboutin2, H. Petitjean1, B. Xerri1, J-P. Flament3 and C. Berthomieu,2 1 ICG MACS, UMR 5253 CNRS/ENSCM/UM2/ UM1 Ecole Nationale Supérieure de Chimie de Montpellier 8, rue de l’Ecole Normale, 34296 Montpellier cedex 5, France 2 Laboratoire des Interactions Protéine Métal, DEVM-DSV, UMR 6191 CNRS-CEAUniv. Aix-Marseille II, 13108 Saint-Paul – lez – Durance, France 3 Laboratoire de Physique des Lasers, Atomes et Molécules, UMR CNRS 8523, PhLAM, Bat. P5, Universite de Lille-1, 59655 Villeneuve d’Ascq Cedex. E-mail: [email protected] Characterizing the properties of active sites remains an experimental challenge for all enzymatic issues in particular for metalloenzymes that represent more than 1/3 of the enzymes. The active site of Cu,Znsuperoxide dismutase reacts very efficiently with superoxide both in the oxidized (Cu2+) and reduced (Cu+) states. To specifically monitor changes at the metal-binding site, a new experiment based on FTIR difference spectroscopy coupled to electrochemistry in the far infrared range (1000-50 cm-1) has been developed [1,2]. Since metal-ligands vibrations contribute in this range new structural information of the metal site center were obtained. DFT calculation of wavenumbers and potential energy distributions of vibrational modes on the protein metal sites were performed. We will show how a DFT approach helps at assigning these new accessible experimental vibrational data of CuI/II, Zn-superoxide dismutase active site. This far-IR domain provides unique markers to track structural changes of redox active sites for proteins in aqueous solution and enables thorough analysis of metal-ligand bond properties, notably metal-histidine interactions often found in enzyme active sites and absorbing below 500 cm-1. Finally, we will show that this approach broadens access of far-IR spectroscopy to a large range of proteins bearing redox metal centres [4]. [1]. C. Berthomieu, L. Marboutin, F. Dupeyrat, et P. Bouyer Biopolymers 2006, 82(4), 363-367. [2]. F. Dupeyrat, C. Vidaud, A. Lorphelin, et C. Berthomieu J. Biol. Chem. 2004, 279, 48091-48101. [3]. Xerri, B.; Flament, J. P.; Petitjean, H.; Berthomieu, C.; Berthomieu, D., J. Phys. Chem. B 2009, 113, 15119-15127. [4] Marboutin, L., H. Petitjean, B. Xerri, N. Vita, F. Dupeyrat, J.-P. Flament, D. Berthomieu and C. Berthomieu, Angewandte Chemie-International Edition, 2011. 50(35): p. 8062-8066.

Keywords: metalloenzymes, DFT, Terahertz

Microsymposia

Reactions of Oxoiron(IV) Porphyrin π-Cation Radicals with Chloride Ion Hiroshi Fujii, Zhiqi Cong, Institute for Molecular Science & Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Okazaki, (Japan). E-mail: [email protected] Chloroperoxidase (CPO) and myeloperoxidase (MPO) are the only heme peroxidases that catalyze oxidation of chloride ion with hydrogen peroxide. Numerous biological studies have suggested that an oxoiron(IV) porphyrin π-cation radical species known as compound I, is responsible for oxidation of chloride ion and for addition of a chloride ion to the ferryl oxygen atom of compound I to produce a transient ferric hypochlorite complex, Fe(III)-OCl. The ferric hypochlorite complex is believed to act as a key compound in the reactions leading to chlorination of organic substrates by CPO and antimicrobial activity in MPO. Although the oxidation process has been studied by multi-mixing stopped-flow experiments in which transiently formed compound I were reacted with chloride ion, spectroscopic evidence for the formation of the ferric hypochlorite complex has not been obtained and it remains unclear how compound I oxidizes chloride ion. Synthetic iron porphyrin complexes have been widely used as models of heme enzymes with the aim of gaining an understanding of the details of the enzymatic reaction mechanisms. While extensive studies have been shown to form compound I model complexes from various iron(III) porphyrin complexes and oxidants, such as m-chloroperoxybenzoic acid, iodosobenzene, and ozone, there are only a few reports of formation of an O-X bond between compound I model complexes and halides as models for CPO and MPO. In this presentation, we report the direct observation of oxidation of chloride ion with synthetic compound I model complexes and subsequent reactions leading to chlorination of organic compounds. In addition, we report that an oxoiron(IV) porphyrin π-cation radical can be converted to iron(III) meso-chloro-isoporphyrin in the presence of TFA and chloride ion and it is an excellent reactive agent for chlorinating aromatic compounds and olefins.

subsequent oxygen transfer to phenolate substrates. The ligands were synthesised following a general procedure that allows the modified Peterson reaction of pyrazoles or almost every substituted pyrazole with an aldehyde to form the desired bis(pyrazolyl)methane ligand.[2] They convince by their good donor properties which are tunable by the substitution pattern and their biomimetic character by resemblance to the ubiquitous occurring histidine. In the special case of HC(3-tBupz)2(py), we were able to identify the room temperature stable μ-η2:η2-peroxo-dicopper(II)-species [(HC(3-tBupz)2(py))2Cu2O2]2+ (Figure 1) which transfers one oxygen atom selectively to phenolic substrates at low temperatures as well as at ambient temperature, hence mimicking tyrosinase activity. This first functional tyrosinase model has been studied by means of UV/Vis absorption spectroscopy (Figure 1), resonance Raman spectroscopy, UHR ESI and density functional theory. Besides the donor competition between pyrazole and pyridine donors, the spectroscopic transitions and the phenolate binding have been analysed in detail. It appears that this complex shows oxidation and oxygenation ability in spite of its stability. Furthermore, the oxygen transfer ability of this system to other model substrates was investigated. A Hammett correlation showed that the oxygenation proceeds electrophilically.[3]

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Figure 1: UV/Vis spectra of the formation of [(HC(3-tBupz)2(py))2Cu2O2] [SbF6]2 and optimised structure

[1] Z. Cong, T. Kurahashi, H. Fujii, Angewandte Chemie Int. Ed., 2011, 50, 9935-9939. [2] Z. Cong, T. Kurahashi, H. Fujii, J. Am. Chem. Soc., 2012, 134, 4469-4472.

[1] L.M. Mirica, X. Ottenwaelder, T.D.P. Stack, Chem. Rev., 2004, 104, 1013-1045. [2] A. Hoffmann, U. Flörke, M. Schürmann, S. Herres-Pawlis, Eur. J. Org. Chem., 2010, 4136-4144. [3] A. Hoffmann, S. Binder, A. Goos, M. Rübhausen, O. Tröppner, I. Ivanovic-Burmacovic, S. Herres-Pawlis, manuscript in preparation.

Keywords: oxoiron complex, high-valent, chlorination

Keywords: tyrosinase model, copper complex, spectroscopy

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MS.D3.C.11

A Full Study on the First Functional Room Temperature Stable Tyrosinase Model Alexander Hoffmann,a Stephan Binder,b Arne Goos,b Michael Rübhausen,b Oliver Tröppner,c Ivana Ivanovic-Burmazovic,c Sonja Herres-Pawlis,a aDepartment of Chemistry, Ludwig-MaximiliansUniversität München, Munich (Germany). bInstitute for Applied Physics and Center for Free Electron Laser, University of Hamburg, Hamburg (Germany), cDepartment of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Erlangen (Germany). E-mail: [email protected]

Unravelling the Reactivity of Zinc Fingers toward H2O2 with Peptidic Models Olivier Sénèque,a Jean-Marc Latour,a aLaboratoire de Chimie et Biologie des Métaux, UMR CNRS-CEA-UJF 5249, Grenoble, (France). E-mail: [email protected]

The activation of dioxygen by Cu(I) complexes plays an important role in biological and synthetic oxidation processes. Tyrosinase and hemocyanin bind the O2 molecule by interaction with two copper atoms under formation of a Cu2O2 unit which contains a peroxo group and divalent copper.[1] Tyrosinase hydroxylates phenols in their orthoposition. This study deals with the copper coordination chemistry of bis(pyrazolyl)methanes, their ability to activate dioxygen and the

Zinc fingers are small protein domains where a Zn2+ ion is bound to the protein by four cysteine or histidine side-chains (Zn(Cys)4-x(His)x ; x=0,1,2). Due to the presence of cysteines in these sites, there are likely targets of reactive oxygen species (ROS = H2O2, O2°–, HOCl, …) produced in cells in conditions of oxidative stress. However, little is known about the reactivity of zinc-bound thiolates with ROS. Our goal is to describe the reactivity of zinc fingers towards ROS in order to get a deeper insight into their involvement in oxidative stress. For this purpose, we use small peptides (< 26 amino-acids) to model the zinc finger sites of various proteins. These peptides are designed to mimic perfectly the structure (peptide folding, hydrogen bond network) of natural zinc finger sites.[1,2,3]

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Microsymposia In this communication, we will report on models of structural zinc fingers of various types (treble clef, zinc ribbon or classical bba) and of the Zn(Cys)4 site of Hsp33, a bacterial holdase involved in the defence against oxidative stress. We will show that these small peptidic models allow detailed characterizations of the coordination properties of zinc fingers (binding constants, protonation state, influence of second coordination sphere) [2,3], as well as in-depth assessment of the products, mechanisms and kinetics of the oxidation reaction with H2O2 [1,4]. We will discuss how zinc-binding can modulate the reactivity of thiols. Indeed, we will show that biologically relevant data concerning the involvement of zinc fingers in peroxidic stress can be obtained from these structurally meaningful models. [1] O. Sénèque, E. Bourlès, V. Lebrun, E. Bonnet, P. Dumy, J.-M. Latour, Angew. Chem. Int. Ed. 2008, 47, 6888-6891. [2] O. Sénèque, E. Bonnet, F. L. Joumas, J.-M. Latour, Chem. Eur. J. 2009, 15, 4798-4810. [3] O. Sénèque, J.-M. Latour, J. Am. Chem. Soc. 2010, 132, 17760-17774. [4] E. Bourlès, M. Isaac, C. Lebrun, J.-M. Latour, O. Sénèque, Chem. Eur. J. 2011, 17, 13762-13772.

Keywords: zinc finger, oxidation, thiolate

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Sorption and structure in biologically-derived MOF materials M.J. Rosseinsky, Department of Chemistry, University of Liverpool The precisely defined interior cavities of porous metal-organic frameworks with a high degree of chemical diversity are attractive for selective sorption. The talk will describe the formation of porous materials based on biologically derived ligands. Amino acids are the simplest of this class of ligands and afford a range of structures depending on the auxiliary functional groups attached to the alpha carbon. We describe a family of amino-acid based open frameworks [1] which display chirally selective sorption that is highly specific to the functional group disposition within the sorbed molecules, formed using aspartic acid and a range of neutral linkers. The nature of the internal pores can be tuned using both linker length and postsynthetic functionalisation, which in turn allows the development of catalytic behaviour [2]. The guest sorption behaviour is studied using computational chemistry approaches. The covalent connection of amino acids into peptides allows the synthesis of metal peptide frameworks [3] as well as pure peptide porous materials [4]. Peptides can function as flexible linkers in metal-organic frameworks and the resulting guest response will be discussed. [5, 6]. The introduction of the porphyrin chromophore used in photosystems allows sacrificial hydrogen generation from water [7].

(2008); T. Takayama et al., B. Chem. Soc. Jpn. 69, 1579 (1996); M. Tiliakos et al., Inorg. Chem. Commun. 8, 1085 (2005); E. Ueda et al., B. Chem. Soc. Jpn. 77, 981 (2004). [4] A. Comotti, S. Bracco, G. Distefano, P. Sozzani, Chem. Commun. 284 (2009); D. V. Soldatov, I. L. Moudrakovski, J. A. Ripmeester, Angew. Chem. Int. Edit. 43, 6308 (2004); C. H. Gorbitz, F. Rise, J. Pept. Sci. 14, 210 (2008). [5] Vaidhyanathan, R., Bridges, C. A., Bradshaw, D. & Rosseinsky, M. J. Crystal Growth & Design 10, 4348-4356, 2010. [6] Rabone, J., Yue, Y. F., Chong, S. Y., Stylianou, K. C., Bacsa, J., Bradshaw, D., Darling, G. R., Berry, N. G., Khimyak, Y. Z., Ganin, A. Y., Wiper, P., Claridge, J. B. & Rosseinsky, M. J. Science 329, 1053-1057, 2010. [7] Fateeva, A., Chater, P., Ireland, C., Tahir, A. A., Khimyak, Y., Wiper, P., Darwent, J. R. & Rosseinsky, M. J. Angewandte Chemie-International Edition, 10.1002/anie.201202471, 2012.

MS.D4.I1 Metalloporphyrin-based MOFs: new strategies for catalyst immobilization Gotzone Barandika,a Begoña Bazán,b Arkaitz Fidalgo-Marijuan,b Miren-Karmele Urtiaga,b Luis Lezama,a María-Isabel Arriortua,b a Department of Inorganic Chemistry, UPV/EHU Vitoria and Leioa (Spain). b Department of Mineralogy and Petrology, Leioa (Spain). E-mail: gotzone.barandika@ehu Metalloporphyrin systems are one of the cornerstones on which the existence of life is based, as major biochemical, enzymatic and photochemical functions depend on the special properties of the tetrapyrrolic macrocycle [1]. Thus, porphyrin catalysts are well-known to be highly efficient in many catalytic reactions and, during the last years, a great effort has been devoted to the immobilization of distinct types of catalysts on solids [2]. In this sense, recent strategy consists of the immobilization of catalysts in MOFs (metal-organic frameworks) [3]. In our group we have started exploring the possibility of using metalloporphyrins both as structural units in MOFs and catalyst [4], in the same compound. Our preliminary results consist of a series of M-porphyrin-bipy compounds (M= Fe, Co; bipy= 4,4’-bipyridine) that have been structurally characterised. Catalytic activity has also been studied.

Structural hierarchy in a zinc aspartate open framework featuring three different metal environments and ligand conformations. (Gould, Chem Comm 2010)

[1] Vaidhyanathan, R et al Angew. Chem. Int. Ed. Engl. 45, 6495 (2006); Ingleson, M. J. et al Chem. Comm. (29), 3036 (2007); Barrio, J. P. et al Chemistry-a European Journal 14 (15), 4521 (2008); Rebilly, J. N. et al, Inorg. Chem. 47 (20), 9390 (2008). J.N. Rebilly et al Chemistry – an Asian Journal 4, 892-903, (2009); Gould J.A. et al Chem. Comm. (46), 2793 (2010); Gould J.A. et al Cryst. Growth Des. 10, 2977 (2010). [2] Ingleson, M. J.et al Chem. Comm. (11), 1287 (2008); Ingleson, M. J. et al Chem. Comm. (23), 2680 (2008). [3] H. Y. Lee, J. W. Kampf, K. S. Park, E. N. G. Marsh, Cryst. Growth Des. 8, 296 (2008); A. Mantion et al., J. Am. Chem. Soc. 130, 2517

[1] I. Beletskaya, V.S. Tyurin, A.Y. Tsivadze, R. Guilard, C. Stern, Chem. Rev.,

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Microsymposia 2009, 109, 1659-1713. [2] J. Mola, E. Mas-Marza, X. Sala, I. Romero, M. Rodríguez, C. Viñas, T. Parella, A. Llobet, Angew. Chem. Int. Ed., 2008, 47, 5830-5832. [3] C. Wang, Z. Xie, K.E. deKrafft, W. Lin, J. Am. Chem. Soc., 2011, 133, 13445-13454. [4] A. Fidalgo-Marijuan, G. Barandika, B. Bazán, M.K. Urtiaga, M.I. Arriortua, Polyhedron, 2011, 30, 2711-2716. This work has been financially supported by the Ministerio de Ciencia e Innovación (MAT2010-15375) and the Gobierno Vasco (Basque University System Research Groups, IT-177-07), which we gratefully acknowledge. SGIker technical support (MEC, GV/EJ, European Social Fund) is gratefully acknowledged. The authors like to thank Dr. Fernando Plazaola (UPV/EHU) for his help in the interpretation of Mössbauer spectra. A. Fidalgo-Marijuan thanks to the UPV/EHU fellowships.

Keywords: Metalloporphyrin, MOF, catalyst

MS.D4.I2 Nanoparticles for Biomedical Diagnosis and Therapy Natividad Gálvez,a Elsa Valero,a José Manuel Domínguez-Vera,a Rafael Cuesta,b Pasquina Marzola,c aDepartamento de Química Inorgánica, Universidad de Granada, Granada (Spain). b Departamento de Química Inorgánica y Orgánica, Universidad de Jaén, Jaén, (Spain). cUniversità degli studi di Verona, Verona, (Italy). E-mail: [email protected] Magnetite and/or maghemite (Fe3O4/γ-Fe2O3) nanoparticles have been used extensively as a model magnetic material in the biomedical research field. In particular, water soluble magnetic iron oxides which are coated with different biocompatible polymers serve as contrast agents for MRI nowadays or as colloidal mediators for cancer magnetic hyperthermia. The conjugation of tiny nanoparticles with specific biomolecules allows researchers to target the desired location and reduce overall toxicity. Incorporation of optical functionality to magnetic nanoparticles is of particular interest. The combination of optical and magnetic properties in a single nanoprobe would allow simultaneous optical and magnetic imaging, which could be of enormous importance, both from a diagnostic and therapeutic point of view. The pH-driven assembly-disassembly process that occurs in the apoferritin protein is effective for the encapsulation of maghemite nanoparticles of different sizes (Apomaghemite).[1] An in vivo biodistribution study showed that Apomaghemite nanoparticles preferentially accumulate in the liver. We have prepared two types of magneto-fluorescent nanostructures by functionalization of Apomaghemites: either using a classic fluorophore or a Quantum Dot. In vivo Optical Imaging (OI) studies pointed out that a substantial fraction accumulated in the liver, which opens the possibility to use them as MRI/OI bimodal probes for liver diseases. [1] Elsa Valero, Stefano Tambalo, Pasquina Marzola, Mariano Ortega-Muñoz, F. Javier López Jaramillo, Francisco Santoyo-González, Juan de Dios López, Juan J. Delgado, José J. Calvino, R. Cuesta José M. Domínguez-Vera and Natividad Gálvez. J. Amer. Chem. Soc. 2011, 133 (13), pp 4889–4895.

Keywords: maghemite, Biomedical Imaging, magnetic-fluorescent nanoparticles

MS.D4.C.01 Construction and Characterization of Supramolecular Hemoprotein Polymers Takashi Hayashi, Koji Oohora, Akira Onoda, Department of Applied Chemistry, Osaka University, Suita, (Japan). E-mail: thayashi@chem. eng.osaka-u.ac.jp

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A series of self-assembly systems in biological molecules are one of the most attractive nanomaterials, which quite often consist of supramolecular biopolymers defined as thermally equilibrated polymeric architectures. The supramolecular composite has been formed by spontaneous connections of the monomer components through non-covalent intermolecular interaction. They are ubiquitous and fulfill the biological functions via well-organized conjugations in nature. Over the last two decades, many groups have prepared a variety of self-assembly systems using organic and/or inorganic frameworks to mimic the biological supramolecular systems. Recently, we have also extended this basic principle of the supramolecular polymer chemistry to the supramolecular protein engineering using hemoproteins. A typical heme cofactor, protoporphyrin IX iron complex, is bound in a number of hemoproteins via non-covalent interaction and heme Fe–ligand coordination. To construct the hemoprotein polymer, a heme moiety was introduced onto the hemoprotein surface via a covalent linkage. After the removal of the native heme cofactor from the heme pocket, intermolecular hemoprotein polymers were obtained as shown in Figure 1. The hemoprotein polymers were characterized by UV-vis spectroscopy and size exclusion chromatography and AFM (atomic force microscopy) analyses. The AMF measurement of the polymers on the HOPG exhibited the beautiful fibrous structures with the length of 300–1000 nm including more than 100 proteins [1]. Our group tried to prepare not only a one-dimensional fibrous polymer but also a blanched polymer [2] and cross-linked polymer [3] using cytochrome b562 or myoglobin. In addition, a myoglobin– streptavidin alternative copolymer was also obtained from a mixture of a biotin-linked heme, myoglobin dimer and streptavidin [4]. Next, the present method is found to serve as a new way to generate an attractive composite between hemoprotein and gold surface. For example, the hemoprotein polymer was architected on the gold electrode [5]. In this presentation, our group will report the construction of supramoelcular hemoprotein polymer and its application for bionanomaterials.

Figure 1. Construction of supramolecular hemoprotein polymer [1] H. Kitagishi, K. Oohora, H. Yamaguchi, H. Sato, T. Matsuo, A. Harada, T. Hayashi, J. Am. Chem. Soc., 2007, 129, 10326-10327. [2] H. Kitagishi, Y. Kakikura, H. Yamaguchi, K. Oohora, A. Harada, T. Hayashi, Angew, Chem. Int. Ed., 2009, 48, 1271-1274. [3] K. Oohora, A. Onoda, H. Kitagishi, H. Yamaguchi, A. Harada, T. Hayashi, Chem. Sci., 2011, 2, 1033-1038. [4] K. Oohora, S. Burazerovic, A. Onoda, Y. M. Wilson, T. R. Ward, T. Hayashi, Angew. Chem. Int. Ed., 2012, 51, 3818-3821. [5] A. Onoda, Y. Kakikura, T. Uematsu, S. Kuwabata, T. Hayashi, Angew. Chem. Int. Ed., 2012, 51, 26282631.

Keywords: hemoprotein, supramolecular polymer, heme

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MS.D4.C.03

Monolayers of metal complexes for nanostructured antibacterial surfaces Piersandro Pallavicini,a Giacomo Dacarro,a Franck Denat,b Alice Donà,a Angelo Taglietti,a aInorganic Nanochemistry Laboratory inLAB, Dipartimento di Chimica, University of Pavia, Pavia, (Italy). b Institut de Chimie Molécularie ICMUB, University of Bourgogne, Dijon (France). E-mail: [email protected]

A New Ferritin Iron Core Growth Model. Consequences on the Study of on Vivo Samples by Electron Microscopy J.J. Delgadoa, J.D. López-Castro,a N. Gálvez,b Rafael Cuestac, JJ Calvinoa and J.M. Domínguez-Vera,b aDpto. Ciencia de Materiales e Ingeniería Metalúrgica y Química Inorgánica, Universidad de Cádiz. b Dpto. de Química Inorgánica. Universidad de Granada. cDpto. de Química Inorgánica y Orgánica. Universidad de Jaén. E-mail: [email protected]; [email protected]

Silica surfaces (glass, quartz, silicon chips bearing a native SiO2 film) are easily coated with monolayers of functional molecules terminating with trialkoxysilane groups. Coordination chemistry can be transferred on this type of nano-modified silica surfaces by equipping traditional ligands with such alkoxysilanes. With the aim of obtaining surfaces capable of exerting an antibacterial action, we have prepared bulk glass surfaces coated with monolayers of the Cu(II) complexes of the 13aneN4 tetraaza macrocycle and of 2,2’-bipyridine. Due to the antibacterial properties of the cupric cations, both surfaces exert a fair microbicidal effect either against Escherichia Coli (Gram -) and Staphilococcus Aureus (Gram+) bacterial strains over a prolonged (24 h) period. The Cu(II) complex of 13aneN4 also exhibits the usual enhanced kinetic inertness of macrocyclic complexes and bears a +2 charge: we have found that its monolayers on glass surfaces can be used as a “glue” for further coating with negatively charged nanoparticles. A successive layer of citrate-stabilized silver nanospheres and of lauryl sulfobetaine-stabilized gold nanostars are deposited on the 13aneN4 monolayer by straightforward solution methods.[1] Glasses coated with [Cu(II)(13aneN4)]/silver nanospheres exert an enhanced microbicidal effect agains Gram- and Gram+ bacteria, better than that of silver nanospheres grafted on glass bearing a mercaptopropyltrilakoxysilane monolayer.[2] Glass coated with [Cu(II)(13aneN4)]/gold nanostars display a strong photothermal effect if irradiated on the nanostar plasmon resonance. As the latter falls in the NearIR range (750-1000 nm) through-tissues laser treatment against biofilms can be imagined e.g. for protheses bearing such monolayers.

Iron plays a crucial role in many essential cellular functions, such as electron and oxygen transport, nitrogen fixation and deoxynucleotide synthesis. However, free iron (non-protein bound) is highly toxic to cells due to its capacity to participate in the formation of reactive oxygen species (ROS) superoxide, peroxide and hydroxyl radicals that cause damage to lipid membranes and other cellular constituents [1]. Living organisms have developed a molecule, ferritin, to store in a non-toxic form the iron that is not required for immediate metabolic needs. Hence, it is crucial to develop new tool for characterizing ferritins with the potential to identify modifications or dysfunctions of ferritins involved in some pathologies. Our work deals with an in deep Electron Microscopy study, in combination with modeling and image simulation, of reconstituted horse spleen ferritins (L subunit-rich) with increasing iron loading which allow us to suggest a new mechanism of iron core formation [2]. Our model is based on the fact that every L subunit contains a nucleation center and the iron core forms in the apoferritin cavity by the formula 24-n centers (where n is the number of H subunits). This model explains i) why all ferritin particles, even the heavily loaded iron cores, are hollow, ii) why horse spleen ferritin, with 90% L chain subunits forms cores with morphologies that have slight imperfections compared to the idealized model of ferritin with 24 nucleation sites, iii) why human heart ferritin, with 67% H chain subunits forms cores with complex morphologies, far from the cubic symmetry and iv) why homopolymers of recombinant human H ferritin do not form organized cores because they lack nucleation sites, but, homopolymers of L ferritin form well-defined, electron-dense cores. The ferritin core morphology is therefore a fingerprint of the protein composition. In addition, the present study suggests that the analysis of the morphology of the ferritin iron core might be used as a TEM biomarker to correlate the L/H subunit composition with the mineral core morphology. In practice, ferritin cores from the tissue of healthy individuals may be compared with those from patients suffering from iron metabolism diseases and the iron mineral morphologies might allow quick diagnosis of diseases, by revealing improper L/H ratios in ferritin.

[1] P.Pallavicini, G. Dacarro, L.Cucca, F. Denat, P.Grisoli, M. Patrini, N. Sok, A. Taglietti, New J Chem, 2011, 35, 1198-1201; [2] P. Pallavicini, A. Taglietti, Y.A. Diaz-Fernandez, M. Galli, P. Grisoli, M. Patrini, G. Santucci DeMagistris, R. Zanoni, J Colloid Interf Sci, 2010, 350, 110-116.

Keywords: self-assembled monolayers, macrocyclic complexes, antibacterial materials

[1] J. Dever, K. Kowdley, Expert Opinion on Medical Diagnostics 2010, 4, 67. [2] J. López-Castro, J. Delgado, J. Perez-Omil, N. Gálvez, R. Cuesta, R. Watt and J.M. Domínguez-Vera. Dalton Trans., 2012, 41, 1320.

Keywords: Ferritin, Electron Microscopy, Iron Core Growth

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Cored Functional Hyperbranched Biopolymers: Nanoreactors for the Preparation and Stabilization of Palladium Nanoparticles Salah-Eddine Stiriba, Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, C/. Catedrático José Beltrán 2, 46980 Paterna, Valencia, (Spain). E-mail: [email protected]

Metal-Organic Functional Nanoparticles with Application on Nano-Biomedicine and Smart Responses F. Novio,a Asli Raman,a D. Ruiz-Molina,a aCentre d’Investigació en Nanociència i Nanotecnologia CIN2, CSIC-ICN (Spain). E-mail: [email protected]

A great interest is placed on the use of palladium clusters and colloids of narrow particle size distributions in the range of 1-10 nm for organic catalysis and material sciences. [1] Such namometarials are for instance affective catalysts for carbon-carbon bond formations due to their large surface area and a unique combination of reactivity. Increasing the control the control of particles size and the stability of the metal nanoparticles remain then a key challenge. An excellent method to prepare palladium nanoparticles involves the chemical reduction of palladium(II) ions with an external reducing agent in the presence of surfactants or polymers with micellar structure such as dendrimers. In view of building biomaterials based on biopolymers for the preparation and stabilization of palladium nanoparticles, we propose using biodegradable amphiphilic hyperbranched polyether polyols, namely polyglycerols, of low polydispersity (1.2 380 nm) was followed in various solvent. Quantum yield measurements were carried out under irradiation by monochromatic light at 470 nm.

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MS.A4.P.167 Synthesis of a Novel Polyoxaaza Schiff-Base Macroligand and Luminescent Properties of the Complex With Eu(III) Sofía Rodríguez, Sara Rodríguez, Perla Elizondo and Nancy Pérez. Peña Yolanda. Universidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, Ave Pedro de Alba S/N Cd. Universitaria, San Nicolás de los Garza, N. L, México, 66450. E-mail: perlaelizondomx1@ gmail.com This work was focused in the synthesis of a new Eu(III) complex with a polioxaaza receiver type and to study of photoluminescent properties. The interest in the synthesis of complexes lies in the photoluminescent properties associated with this type of compounds, thus, can be applied in the development of light emitting devices [1]. A novel polyoxaaza Schiff-base macroligand L, has been synthesized from the condensation reaction between 2,6-bis(2formylphenoxymethyl)pyridine (P) and N,N´,N´´(aminobencyl) tris(2-aminethyl)imine (A) (Scheme 1). The complex, EuL, were obtained via template, in relation 1:1:1, P: A: Eu(III).5H2O(NO3)3. Compounds were characterized by elemental analysis, IR, 1H and 13C RMN

spectroscopy and thermal analysis. This showed that the M:L ratio in the complexes is 1:1 and suggest that two molecules of water and three nitrates are associated in the same one. Compound (L). Yellow solid (87%), m.p. 127.9ºC. Anal. Calcd. for C48H46N8O2 .2CH3OH: C, 60.70; H, 6.68; N, 13.85. Found: C, 72.30; H, 6.51; N, 13.49. IR (ATR) 1596 n(C=N)py, 1631 n(C=N)imin, 1237 n(C-O-C). Compound (EuL). Orange solid (87.7%), m.p. 173ºC. Anal. Calcd. for C48H46N11O11 . 2H2O: C, 50.53; H, 4.27; N, 13.34. Found: C, 50.87; H, 4.41; N, 13.60. IR (ATR) 1596 n(C=N)py, 1635 n(C=N)imin, 1229 n(C-O-C), 1330, 1035, 827 n(NO3-). The TG profile showed weight loss of 3.30 (calcd. 3.33) up to 120 °C, which indicates the crystallization or coordinated water molecules in the complex. The complex underwent a two-stage decomposition started at 240 °C and was completed at 330 °C, with a mass loss of 18.57 % (calcd. 18.45 %), corresponding to the loss of pendant moiety, The second stage of decomposition occurred in the temperature range 420–540 °C, with a mass loss of 57.93 % (Calcd. 58.91 %) due to the oxidative decomposition of the complex to Eu2O3. The complex showed photoluminescent properties in 1x10-5 mol/L acetonitrile solution. The Eu(III) complex in solid state under UV irradiation (254 and 366 nm), emit a bright orange light. The spectrum of Eu(III) complex, show two characteristic emission bands at 616 and 673 nm aproximalety, are corresponding to 5D0→7F2 and 5D0→7F4 respectively[2]. The photoluminescence signal intensity at 616 nm of the complex in solution, was increased with respect to that showed for Eu(III) salt, indicating that L is an effective sensitizer for f-f lanthanides transitions. According to these results, increase the interest on the synthesis of new lanthanides complexes and applied in the preparation of new materials with photoluminescent properties.

groups in the construction of metal-based supramolecular triangles as 60° angular building blocks is well known in literature [2]. In this work, two new metal-organic supramolecules, [Pd6(m-tmbim)3(mPz)6] (1) and [Pd6(m-bpym)3(m-Pz)6]Cl6 (2) (tmbim = 2,2’-bis4,5-dimethylimidazolate dianion; Pz = pyrazolato anion; bpym = 2,2′-bipyrimidine) were synthesized. Treatment of a solution containing Pd(II) and the appropriated bis-chelating ligand (tmbim or bpym) with pyrazolato anions yielded 1 and 2, respectively, in moderate yields. Anal.Calcd. for C48H54N24Pd6(%), 1: C, 35.91; N, 20.94; H, 3.39. Found: C, 31.54; N, 20.07; H, 3.11. Calcd.for C42H36N24Cl6Pd6(%), 2: C, 29.19; N, 20.47; H, 2.10. Found: C, 29.00; N, 21.41; H, 2.32. The exobidentate coordination of pyrazolato group in 1 and 2 was suggested by the shift to lower frequency (1487 cm-1) of the nring band when compared with the free ligand (1558 cm-1).The 1H-NMR spectra is consistent with a highly symmetrical structure and is indicative of a single product in solution. The quadridentate chelating mode of tmbim(1) or bpym(2) was deduced by the appearance of one single signal at 2.60 ppm assigned to the CH3 groups in 1and by the presence of two double doublets at 9.34 and 9.29 and one triplet at 7.98 ppm (2). On the basis of elemental analyses and spectroscopic data, we suggest that the structure of compounds 1 and 2 consists of a hexanuclear triangular architecture in which the core “Pd(m-Pz)2Pd” acts as vertices whereas the edges of the triangle are composed by quadridentate chelating L ligands {L = tmbim (1), bpym(2)}. Preliminary host-guest experiments indicated that, on immersing a freshly prepared sample of 1 in CHCl3, the color and the crystallinity of the solid have changed. The resulting material was filtered off, and dried in vacuum. Energy dispersive X-ray spectra (EDX) results clearly showed the presence of chlorine (from CHCl3) in the solid isolated after the immersion. Taking into account that the sample was treated with high vacuum as well the probable existence of a cavity in 1, it seems plausible the occurrence of encapsulation of chloroform inside its cavity. New binding experiments are currently underway in order to acquire more information about the ability of 1 and 2 to accommodate small guests. DFT calculations are also in progress aiming at estimating the size of the cavity. [1] M. Yoshizawa, J. K. Klosterman, M. Fujita, Angew. Chem. Int. Ed. Engl., 2009, 48, 3418-3438. [2] J.Pérez, L. Riera, Eur. J. Inorg. Chem., 2009, 33, 4913-4925.

Scheme 1. The preparation of EuL [1] K. Binnemans, Chem. Rev., 2009, 109, 4283-4374. [2] N. Shavaleev, R. Scopellti, Inorg. Chem., 2009, 48, 6178-6191.

Keywords: lanthanide, luminescent, macroligand

MS.A4.P.168 Self-Assembly of New Pd(II) Metallocages Bearing Pyrazolates as Angular Building Blocks Regina C. G. Frem,a Cristiana da Silva,a Adelino V. G. Netto,a Antonio E. Mauro,a Silmar J. S. Franchi,a Patrícia B. da Silva,a Oswaldo TreuFilho,a Patrícia Silva,b Filipe A. A. Paz,b aInstitute of Chemistry, Univ. Estadual Paulista-UNESP, Araraquara, (Brazil).bCICECO, Department of Chemistry, University of Aveiro, Aveiro (Portugal). E-mail: [email protected] Coordination-driven self-assembly is one of the most powerful synthetic protocols used to construct well-defined metal-organic container molecules. Discrete metal-assembled hosts have attracted considerable attention not only for their peculiar molecular recognition properties, but also for mediating a sort of chemical transformations on their encapsulated guest molecules [1].Among the several 2D discrete metal-based assemblies, the triangle is considered the simplest and smallest member of this group. Particularly, the use of pyrazolato

Keywords: self-assembly, pyrazolates, host-guest chemistry

MS.A4.P.169 Lanthanoid Complexes for Quantum Error Correction Alejandro Gaita-Ariño,a José-Jaime Baldoví,a Salvador CardonaSerra,a Juan-Modesto Clemente-Juan,a Eugenio Coronado,a Guillermo Mínguez-Espallargas,a aInstitute for Molecular Science, University of Valencia, Valencia, (Spain). E-mail: [email protected] Quantum error correction plays a crucial role in quantum information processing. Shor’s quantum error correction code uses nine qubits to encode and protect a single qubit from arbitrary singlequbit errors. We show that the complex ground-state structure of a molecule containing three coupled 159 Tb3+ ions is equivalent to nine electron-nuclear qubits. We present the general scheme to implement Shor’s code on such a molecule in an Electron-Nuclear DOuble Resonance (ENDOR) setup. We offer also concrete guidelines for two relevant sub-codes and we discuss two systems from coordination chemistry that would be adequate from an experimental point of view: [{Tb(TETA)}2 Tb(H2 O)8 ]+ and Tb3 Q9 (TETA=1,4,8,11tetraazacyclotetradecane-1,4,8,11-tetraacetic acid, Q=quinolinate).

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Poster Sessions We have recently shown that the microwave assisted synthesis and solvothermal synthesis are two useful alternatives to prepare diruthenium complexes.[2] Using solvothermal synthesis we have obtained single crystals of linear or zigzag chains of halotetraamidatodiruthenium complexes (Scheme 1).

Scheme 1. Structure of one-dimensional tetraamidato-diruthenium complexes

The electrical conductivity in one-dimensional compounds constructed with tetracarboxylatodiruthenium units has been little explored but the measurements on tetraamidatodiruthenium compounds are unknown. In this communication we extend this type of studies to tetraamidato complexes, Ru2X(μ-NHOCR)4 (X = Cl, Br and I), since they show analogous structures and similar magnetic properties than the corresponding carboxylato compounds. Electrical conductivity measurements of the one dimensional polymeric complexes [Ru2X(m-NHOCC6H4-o-Me)4]n (X = Cl, Br and I) show a similar semiconducting behaviour with a high activation energy for all of them. Conductivity values follow the expected order based on the orbital overlap (Cl < Br < I) whereas the average values of the activation energy follow the inverse order (I < Br < Cl) also in agreement with the better orbital overlap expected for the larger halogens. Keywords: lanthanoid, qubit, quantum error correction

MS.A4.P.170 Electrical Conductivity in One-dimensional Diruthenium Complexes with Amidate Ligands Rodrigo González-Prieto,a Patricia Delgado-Martínez,a Carlos J. Gómez-García,b Reyes Jiménez-Aparicio,a José L. Priego,a a Departamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria, 28040 Madrid (Spain). bInstituto de Ciencia Molecular, Universidad de Valencia, Parque Científico, 46980 Paterna, (Spain). E-mail: [email protected] In the last few years, the potencial uses of diruthenium complexes in molecular materials and nanochemistry have led to renewed interest [1] due to their interesting magnetic and electronic properties. The use of halide ligands as linkers between diruthenium units leads to onedimensional complexes also called MMX polymers. However, MMX polymers of ruthenium with amidate ligands bridging the metal atoms are scarce compared with the tetracarboxylato complexes.

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[1] (a) R. Kuwahara, S. Fujikawa, K. Kuroiwa, N. Kimizuka, J. Am. Chem. Soc., 2012, 134, 1192–1199. (b) L. Welte, R. González-Prieto, D. Olea, M. R. Torres, J. L. Priego, R. Jiménez-Aparicio, J. Gómez-Herrero, F. Zamora, ACS Nano, 2008, 2, 2051–2056. (c) D. Olea, R. González-Prieto, J. L. Priego, M. C. Barral, P. J. de Pablo, M. R. Torres, J. Gómez-Herrero, R. Jiménez-Aparicio, F. Zamora, Chem. Commun., 2007, 1591–1593. [2] S. Herrero, R. JiménezAparicio, J. Perles, J. L. Priego, S. Saguar, F. A. Urbanos, Green Chem., 2011, 13, 1885-1890.

Keywords: Tetraamidato complexes, Conductivity, Nanochemistry

MS.A4.P.172 The Enriched Coordination Chemistry of a Modified PyrimidineHydrazone Ligand Lyall R. Hanton, Daniel J. Hutchinson, Stephen, C. Moratti. Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand. E-mail: [email protected] Molecular strands of pyrimidine-hydrazone (pym-hyz) units have been shown to undergo structural isomerisation from a helical shape to a linear conformation due to the coordination of suitable metal ions. [1] In order to use this phenomenon to power useful devices, such as

actuators, we have added terminal hydroxymethyl arms to a ditopic pym-hyz ligand to allow the incorporation of the ligand into a polymer gel network. However, the positioning of the hydroxymethyl arms allows them to interfere with the binding of the metal ions. Consequently the coordination chemistry of our pym-hyz ligand is much more complicated than those previously reported.[1] An excess amount of copper(II), lead(II), zinc(II) and silver(I) ions have all been shown to create linear complexes with our ligand in solution and the solid state. However, reacting our ligand with a stoichiometric amount of copper(II) resulted in mono-copper bent complexes instead of the expected [2x2] grids seen with other pym-hyz ligands.[2] [2x2] grids were synthesized by reacting our linear with stoichiometric amounts of lead(II) salts, however the binding of the hydroxymethyl arms to the lead(II) ions resulted in considerable distortions to the grid shape. [3] Reacting silver(I) ions with our ligand resulted in the expected linear and double helicate complexes in solution, however the relative abundance of these complexes was not only dependent on the metal to ligand ratio used, but also the solvent and counteranion of the silver(I) salt. A dimeric linear silver(I) complex was also characterized by X-ray crystallography. The rich variety of complexes of our ditopic pym-hyz ligand in both solution and the solid state will be presented.

[1] (i) A.-M. Stadler, N. Kyritsakas, R. Graff, J.-M. Lehn, Chem.- Eur. J., 2006, 12, 4503-4522. (ii) A.-M. Stadler, N. Kyritsakas, G. Vaughan, J.-M. Lehn, Chem.-Eur. J., 2007, 13, 59-68. (iii) X.-Y. Cao, J. Harrowfield, J. Nitschke, J. Ramirez, A.-M. Stadler, N. Kyritsakas-Gruber, A. Madalan, K. Rissanen, L. Russo, G. Vaughan, J.-M. Lehn, Eur. J. Inorg. Chem., 2007, 2944-2965. [2] D. J. Hutchinson, L. R. Hanton, S. C. Moratti, Inorg. Chem. 2010, 49, 59235934. [3] D. J. Hutchinson, L. R. Hanton, S. C. Moratti, Inorg. Chem. 2011, 50, 7637-7649.

Coexistence of the ferroelectricity and ferromagnetism has been attracted extensive interests to develop novel multi-functional materials. We have been developing a ferroelectric molecular rotator in [Ni(dmit)2] crystals, where two-fold flip-flop motion of polar m-fluoroanilinium resulted in the ferroelectric-paraelectric transition at 346 K [1]. Single molecule magnets (SMMs) are one of the promising candidates to introduce such dielectric functions into molecular-based magnets due to the slow magnetic relaxation of spin flipping and magnetic hysteresis. Herein, we report the SMMs with polar rotational ligands of difluoroacetate (CHF2COO−) and m-fluorobenzoate (m-FPhCOO−). The crystal structures, dielectric and magnetic properties of two new crystals of [Mn12O12(CHF2COO)16 (H2O)4]·2CH2Cl2·4H2O (1) and [Mn12O12(m-FPhCOO)16(H2O)4]·2(mFPhCOOH)·8CH2Cl2 (2) were examined. Ligand exchange reactions using corresponding carboxylate ions yielded black single crystals of 1 and 2. In crystal 1, axial direction of {Mn12O12}-disk was arranged along the c-axis, which was parallel to the magnetic easy axis. Orientational disorder of –CHF2 groups were observed at axial six CHF2COO− ligands and at equatorial eight ligands parallel to the ab-plane at 100 K. In crystal 2, the axial direction of {Mn12O12}-disk was corresponded to the a-axis. The orientational disorder of F-atoms at m-positions of phenyl-rings was observed in four equatorial- and four axial-coordinated m-FPhCOO− ligands at 100 K. When these orientational disorders were dynamic properties, the change in the dipole moments was expected to achieve the dielectric responses. In addition, large solvent accessible voids were observed in crystals 1 and 2, which spaces were occupied by crystallization solvents of CH2Cl2 and H2O in 1 and neutral m-FPhCOOH and CH2Cl2 in 2. Magnetic properties of crystals 1 and 2 were characterized. Both crystals showed a large M-H hysteresis loop at 1.8 K with the step at 0 T due to quantum spin tunnelling and frequency-dependent, whereas the ac susceptibilities were also consistent with the SMM behaviour of typical Mn12 clusters. From the Arrhenius plots of ac susceptibilities, the relaxation parameters of ΔE = 49 cm−1 and τ0 = 3.4 s for crystal 1 and ΔE = 46 cm−1 and τ0 = 2.9 s for crystal 2 were deduced. Magnetic blocking temperatures (τ = 100 s) of crystals 1 and 2 were 3.2 and 3.0 K, respectively. Although the magnetic parameters of crystals 1 and 2 were quiet resemble to each other, completely different dielectric responses were observed. In crystal 1, two-step dipole freezing were observed at ~220 and ~100 K. From the Arrhenius plots of dielectric measurements in crystal 1, the activation energies at relaxations of ~220 and 100 K were 66 and 12 kJmol-1, respectively, which corresponded to the potential energy barrier for the molecular rotation and/or fluctuation of dipole units. On the contrary, both of the temperature- and frequency-dependent dielectric responses were not observed in crystal 2, suggesting that the orientational disorder of F-atoms in m-FPhCOO− ligands was static. [1] T. Akutagawa, H. Koshinaka, D. Sato, S. Takeda, S. Noro, H. Takahashi, R. Kumai, Y. Tokura, T. Nakamura, Nature Mat., 2009, 8, 342.

Keywords: Single Molecule Magnet, Dielectric Properties

Keywords: : Isomerisation, coordination, supramolecular

MS.A4.P.173 Dielectric Anomalies of Single Molecule Magnets with Polar Rotational Ligands Norihisa Hoshino, Tomoyuki Akutagawa, Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, Sendai (Japan). E-mail: [email protected]

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Poster Sessions MS.A4.P.174

MS.A4.P.175

Oligo-nuclear Cobalt Complexes of Fused Salphens and Their Function as Near-Infrared Dye Hirohiko Houjou, Yuta Nagano, Muneyuki Ito, Keisuke Yagi, Institute of Industrial Science, The University of Tokyo, Tokyo (Japan). E-mail: [email protected]

Using Polymers to Amplify the Isomerisation of PyrimidineHydrazone Strands Daniel J. Hutchinson, Lyall R. Hanton, Stephen C. Moratti. Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand. Email: [email protected]

Recently, p-conjugated framework composed of salen/salphen complexes is attracting growing interest [1]. We have so far studied about fused salphen complexes that contain naphthalene-2,6-diol moieties as linker units. Through the studies on di- and trinuclear complexes with Ni, Cu, and Zn ions, we found that their photophysical properties innate to the p-conjugated system are finely tuned by the nature of the metal ion. This finding led us to try another variation of metal ions. Meanwhile, the redox chemistry of salen/salphen complexes exhibits such interesting phenomena as valence tautomerism, when a redox-active metal center like CoII/III is employed. In this study, we have prepared some Co complexes of fused salphen ligands, and investigated their spectroscopic and electrochemical properties. Trinuclear complex [Co3(tri-L)](BF4)3 and related compounds were isolated as 4-dimethylaminopyridine adduct. The UV-VisNIR absorption spectra of these complexes exhibited intense peak around 400 nm and 600 nm. Each complex showed well-resolved multistep redox waves on cyclic voltammogram. The first oxidation wave was observed at lower potential as the nuclearity increases. Upon electrochemical oxidation at 1200 mV (vs. Ag+/Ag), a broad absorption band appeared in >800 nm region with moderate intensity. Simultaneously, a new peak at 650 nm developed while the peak at 600 nm diminished. The change in spectra was substantially reversible with respect to switching of the potential. The absorption band in near-infrared region may have resulted from a generation of phenoxyl radical on the naphthalenediol moiety. Relatively high intensity of this band implies some specific electronic effects, for example charge transfer between metal and ligand.

In recent years polymer gels have emerged as a new actuating technology due to their characteristically large volume changes that can be triggered by a range of external stimuli.[1] We are currently working towards creating a polymer gel which exhibits expansion and contraction due to dynamic changes in the ligand component of the gel upon coordination with metal ions. To this end we have synthesised a series of pyrimidine-hydrazone (pym-hyz) strands that have terminal hydroxymethyl or acryloyl groups. These functional groups allow the pym-hyz strands to be incorporated into a co-polymer gel network. X-ray crystallographic and NMR studies have shown that the strands are coiled in their free state, with the pym-hyz linkages in a transoid conformation. Upon coordination with suitable metal ions the strands uncoil into a linear arrangement as the pym-hyz linkages rotate to a cisoid conformation. [2]Copper(II), lead(II), zinc(II) and silver(I) ions have all been shown to cause this dynamic change, resulting in expanded linear complexes when an excess of the metal ion is used.[3] Co-polymer gels of the pym-hyz strands and methyl acrylate have been shown to swell in solvent upon coordination of metal ions. It is hypothesised that the extent of swelling is dependent on the uncoiling of the pym-hyz strands within the gel. In this way the incorporation of the pym-hyz ligands into a polymer gel network allows for the amplification of the ligands’ structural isomerisation from a molecular scale phenomenon to a macroscopic device.

[1] H. J. Schneider, R. M. Strongin, Acc. Chem. Res., 2009, 42(10), 1489- 1500 [2] A. M. Stadler, N. Kyritsakas, R. Graff, J-M. Lehn, Chem. Eur. J., 2006, 12, 4503-4522. [3] (a) D. J. Hutchinson, S. A. Cameron, L. R. Hanton, S. C. Moratti, Inorg Chem, 10.1021/ic2025582. (b) D. J. Hutchinson, L.R. Hanton, S. C. Moratti, Inorg Chem. 2011, 50, 7637-7649. (c) D. J. Hutchinson, L. R. Hanton, S. C. Moratti, Inorg. Chem. 2010, 49, 5923-5934.

Keywords: Polymers, Actuation, Isomerisation [1] C. J. Whiteoak, G. Salassa, A. W. Kleij, Chem. Soc. Rev., 2012, 41, 622-631, and references therein.

MS.A4.P.176

Keywords: salphen complex, redox, near-infrared absorption

Magnetic and Electrical Properties of a Cyanide Bridged Chiral 1-D Chain Complex Fumichika Iijima,a Norihisa Hoshino,a Norifumi Yoshida,a Takuya Shiga,a Graham N. Newton,a Akiko Nakao,b Youichi Murakami,b Kou Tazoe,c Michael Baker,c Hiroyuki Nojiri,c and Hiroki Oshio,a aGraduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba,

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(Japan). bHigh Energy Accelerator Research Organization, Tsukuba, (Japan) cInstitute for Materials Research, Tohoku University, Sendai, (Japan). E-mail: [email protected] Bistable compounds can exist in two interchangeable phases under identical conditions, and can act as switches when external stimuli are applied. A cyanide-bridged multinuclear complex can show interesting behavior due to the magnetic and electronic interactions between metal centers. In particular, cyanide bridged Fe-Co complexes can show bistability between a diamagnetic LT state (LS CoIII LS FeII) and a paramagnetic HT state (HS CoII LS FeIII) as a result of reversible electron transfer between FeII/III and CoIII/II ions and subsequent cobalt ion spin state transition. This behavior has been described as Electron Transfer Coupled Spin Transition (ETCST) behavior. However, the majority of compounds displaying this behavior are discrete (0-D) molecular systems or bulk (3-D) materials. Previously, we reported a single-chain magnet (SCM) composed of FeIII and NiII ions. [1] In our attempts to develop multifunctional molecular materials showing bistability, we tried to synthesize a cobalt-iron analogue of our previously reported SCM. In this work, a chiral Fe-Co cyanide bridged 1-D chain complex, catena-[FeCo(CN)3(tp)(L)](BF4)∙MeOH∙2H2O (1·MeOH·2H2O, tp = tris-(pyrazolyl) borohydride, and L = bidentate chiral ligand), was synthesized and was found to be ETCST-active. Its thermal and photo induced ETCST behavior was investigated by Mӧssbauer spectra, magnetic susceptibility, and single crystal X-ray analyses. At room temperature, a paramagnetic HT state (HS CoII- LS FeIII) was stabilized. Spin transition with large thermal hysteresis occurred around 250-280 K, and a diamagnetic LT state (LS CoIII- LS FeII) was stablized below 250 K. Concomitant electrical conductivity / permitivity switching was observed. In the low temperature region, the photo induced HT state showed slow magnetic relaxation originating from its 1-D magnetic structure. [1] N. Hoshino, Y. Sekine, M, Nihei, and H. Oshio. Chem. Commun. 2010, 46, 6117.

with 4-cyanopiridine the mononuclear complex Ni(O2CC14H9)2(4CNC5H4)2(OH2)2 (Figure 1b) is formed. In this compound the nickel atom is surrounded by two monodentate carboxylate groups, two cyanopyridines, and two water molecules. One-dimensional chains of the type [Ni(O2CC14H9)2(4,4´-bpy)]n are formed when 4,4´-bpy is used. This compound displays a zigzag chain of mononuclear cis-Ni(O2CC14H9)2 units joined by 4,4´-bypiridine ligands (Figure 1c).

Figure 1. Structure of complexes Ni(μ-O2CC14H9)2(O2CC14H9)2(μ-OH2)(py)4 (a) and Ni(O2CC14H9)2(4-CNC5H4)2(OH2)2 (b). Zigzag chain, in the solid state, of [Ni(O2CC14H9)2(4,4´-bpy)]n (c). Hydrogen atoms are omitted for clarity. [1] S. R. Batten, S. M. Neville, D. R. Turner, Coordination Polymers: Design, Analysis and Application, Royal Society of Chemistry, Cambridge, 2009.

Keywords: magnetic, electron transfer, bistability

Keywords: nickel, carboxylato complexes, one-dimensional

MS.A4.P.177

MS.A4.P.179

Anthracenecarboxylato Complexes of Nickel Belén Jerez,a Miguel Cortijo,a Santiago Herrero,a Reyes JiménezAparicio,a José L. Priego,a M. Rosario Torres,b aDepartamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Madrid (Spain). bCentro de Asistencia a la Investigación de Rayos X, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Madrid (Spain). E-mail: belenjerezsanchez@ estumail.ucm.es

Multifunctional Spin-Crossover Materials Laurence Kershaw Cook, Malcolm Halcrow. Department of Chemistry, University of Leeds, LS2 9JT, UK. E-mail: [email protected]

The reaction of an inorganic nickel(II) salt with carboxylic acids gives compounds with very different stoichiometries and structures depending on the nature of the acid and the reaction conditions [1]. In the present work, we explore the reaction of NiCO3·2Ni(OH)2·nH2O with 9-anthracenecarboxylic acid (HO2CC14H9) in different conditions to obtain discrete and polymeric complexes. The molecular complex Ni(O2CC14H9)2(OHC2H5)2(OH2)2 is obtained by the reaction of the nickel salt with the carboxylic acid in a mixture of ethanol and water. This compound reacts with an excess of pyridine to yield the dimetallic complex Ni2(m-O2CC14H9)2(O2CC14H9)2(m-OH2)(py)4 (Figure 1a), where the nickel atoms are bridged by two carboxylate ligands and one water molecule; the coordination of each nickel ion is completed with one monodentate carboxylate group and two pyridine ligands. Although N,N´-donor ligands are usually needed to obtain higher dimensionality, when the above-mentioned reaction is carried out

A series of iron, cobalt and ruthenium salts have been prepared containing derivatives of the heavily studied 2,2’;6’,2’’-terpyridine ligand system. The electronic properties of the metal complexes have been modulated by increasing the electron deficiency about the trischelate terpyridine ring system. Instead of the typical method which involves introducing electron-withdrawing substituents at different positions on the aromatic rings, replacement of CH groups with noncoordinating electron-deficient nitrogen atoms has been investigated. Utilising this approach, the volume of the disubstituted metal dications is altered only marginally and the roughly spherical shape of the molecules is maintained.[1] A large number of diazinyl derivatives of 2,2’;6’,2’’-terpyridine have been prepared by adapting known literature procedures for related chelators. The iron (II) and cobalt (II) salts have been subject to 1H NMR and EPR spectroscopy and solid-state variable temperature magnetic susceptibility measurements via the use of a SQUID magnetometer in order to attain information on their spin-switching behaviour. X-ray structures were deduced to provide information on solid state packing, and the electronic structures probed using cyclic voltammetry and absorption spectroscopy. The corresponding ruthenium (II) salts

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Poster Sessions were also, where possible, synthesised and isolated. The influence of the increased back-bonding of the electron deficient ligands upon the valence energy levels of the metal centre was deduced using the aforementioned spectroscopic techniques. In addition, the ruthenium salts were subject to fluorescence measurements to assess their room temperature emission due to an increase in the emissive properties observed in previously synthesised complexes of terpyridine derivatives.[2]

and S-coordination play an important role on the photo- and vapourcontrolled luminescence of 1.

[1] C. Tovee, C. Kilner, J.Thomas and M. Halcrow, CrystEngComm, 2009, 11, 2069-2077. [2] M. Maestri, N. Armaroli, V. Balzani, E. Constable and A. C. Thompson, Inorg. Chem., 1995, 34, 2759-2767.

Keywords: spin-crossover, iron, ruthenium

MS.A4.P.180 Photo- and Vapour-Controlled Luminescence of Rhombic Dicoppoer(I) Complex with DMSO Ligand Atsushi Kobayashi,a Kahori Komatsu,a Hiroki Ohara,a Waka Kamada,a Kiyoshi Tsuge,b Ho-Chol Chang,a Masako Kato,a aDivision of Chemistry, Faculty of Science, Hokkaido University, Hokkaido, (Japan). bDepartment of Chemistry, Faculty of Science, Toyama University, Toyama, (Japan). E-mail: akoba@sci. hokudai.ac.jp The materials showing chromotropism have attracted much attention because of their potential application for various sensing devices. We have recently reported on several vapochromic complexes built from Pt(II)-diimine complexes [1,2] or hydrogen-bonded protontransfer assemblies [3,4]. In this work, to develop a new luminescent multichromic system composed of non-precious metal ion, we have focused on copper(I) complexes bound by DMSO (DMSO = dimethyl sulfoxide) ligand, because copper(I) complexes are well known to exhibit strong phosphorescence and DMSO ligand would enable us to modify the luminescence property of Cu(I) centre by linkage isomerization between the O- and S-coordination modes. Herein, we report on the photo- and vapour-controlled luminescence of dicopper(I) complexes with DMSO ligand, [Cu(DMSO)(PPh3)-(m-I)2-Cu(DMSO) (PPh3)] (1). Figure shows the luminescence spectral change of complex 1 under light irradiation (l = 350 nm) at room temperature. In the first 5 min irradiation (1st step), the initial blue emission band centred at 435 nm decreased very rapidly, and a new broad green emission band at around 500 nm appeared (Fig. (a)). In the irradiation time between 5 min and 2 hours (2nd step), the newly appeared green emission band was gradually shifted to lower energy about 14 nm (Fig. (b)). In further UV light irradiation more than 2 hours (3rd step), the emission band was slowly shifted to lower energy about 23 nm and the intensity remarkably increased (Fig. (c)). Interestingly, the initial blue emission at 435 nm was recovered by exposure to saturated DMSO vapour for several hours at 363 K without UV light irradiation. These results clearly indicate that the luminescence property of 1 can be controlled by light irradiation and exposure to DMSO vapour. IR spectral change of 1 under UV-light irradiation suggests that both desorption/adsorption and linkage isomerization of DMSO ligand between O-coordination

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[1] A. Kobayashi, et al., Dalton Trans., 2012, 41, 1878-1888. [2] A. Kobayashi, et al, Dalton Trans, 2011, 40, 8012-8018. [3] A. Kobayashi, et al., Inorg. Chem., 2011, 50, 8308-8317. [4] A. Kobayashi, et al., J. Am. Chem. Soc., 2010, 132, 15286-15298.

Keywords: Copper, photochromism, vapochromism

MS.A4.P.181 Double Complex Salts as Promising Precursors of CuxRu1-X Metastable Nanoalloys Sergey V. Koreneva,b, Evgeny Yu. Filatova,b, Svetlana A. Martynovaa, Nataliya V. Kuratievaa,b, Pavel E. Plusnina,b aNikolaev Institute of Inorganic Chemistry, Novosibirsk, (Russia). bNovosibirsk State University, Novosibirsk,(Russia). E-mail: [email protected] The study of processes occurring at the two-phase ruthenium - copper boundary is of interest for application of ruthenium as an ultrathin barrier layer for copper metallization of interconnects in integrated circuits [1]. The use of ruthenium as a good diffusion barrier is considered as a promising future for the copper metallization technology [2], [3]. In the equilibrium the solid and liquid metals do not mix with each other, the maximum solubility of copper in ruthenium is about 2.5 at% [4]. The use of thermolysis of complex precursor compounds that contain both metals - ruthenium and copper - allows obtaining nano-sized metastable solid solutions with larger mutual solubility of metals. In this work three new double complex salts simultaneously containing ruthenium and copper have been synthesized: [Ru(NH3)5Cl] [Cu(C2O4)2]·H2O (I), [RuNO(NH3)4OH][Cu(C2O4)2]·1.5H2O (II) and [RuNO(NH3)5]2[Cu(C2O4)2(H2O)2][Cu(C2O4)2H2O]2·2H2O(III). The obtained salts have been characterized by IR spectroscopy, analytical data, powder and single-crystal X-ray diffraction. The prepared compounds aren’t isostructural and they crystallize in monoclinic (I, IIIb) and triclinic (II, IIIa) crystal systems (space groups (I) P21/n, Z=4, (II) P-1, Z=1, (IIIa) P-1, Z=2 and (IIIb) P21/c, Z=2). Crystal structures of these compounds consist of separate cations and anions. Preparation of metastable nano-sized powders containing ruthenium and copper was carried out under different atmospheres: reducing, oxidizing, and inert. Thermolysis products were examined by X-ray diffraction (XRD), the composition of the obtained solid solutions was estimated by the Retgers rule. Metastable solid solutions with the highest content of Cu were obtained in hydrogen atmosphere:

Poster Sessions

P.MS.A4

compound (I) - 15% at. Cu, (II) - 10% at. Cu, (III) - 23% at. Cu. It has been demonstrated that copper metal, which is not incorporated in the solid solution, can be removed by chemical etching. In an oxidizing atmosphere the final product is a mixture of oxides RuO2 and CuO. [1] C.-C. Yang, S. Cohen, T. Shaw, at al., Electron Device Letters 2010, 31, 722 - 724. [2] C.-C. Yang, F.R. McFeely, B. Li, at al., Electron Device Letters 2011, 32, 806 - 808. [3] Xin-Ping Qu, Jing-Jing Tan, Mi Zhou at al., MRS Proceedings, 2006, 914, 0914-F09-02. [4] P.R. Subramanian, D.E. Laughlin, Cu-Ru (Copper-Ruthenium), Binary Alloy Phase Diagrams, Second Edition, Ed. T.B. Massalski, ASM International, Materials Park, Ohio, 1990, 1467-1468.

Keywords: ruthenium, copper, thermolysis

MS.A4.P.183 Heteroleptic Bis(dipyrrinato)Zn(II) Complex with Intense Photoluminescence Shinpei Kusaka,a Mizuho Tsuchiya,a Ryota Sakamoto,a Hiroshi Nishihara,a aDepartment of Chemistry, School of Science, The University of Tokyo, Tokyo, (Japan). E-mail: [email protected] Dipyrrin is a mono-valent bidentate ligand, and is known to coordinate with various metal ions. A boron difluoride dipyrrin complex (BODIPY) is famous because of its strong light absorption, fluorescence and photostability, so that it is widely investigated as chemosensors, bioimaging, and optical materials. Dipyrrin metal complexes can be also fluorescent, especially zinc(II) complexes have the highest fluorescence quantum yield (fF) among them. The advantage of bis(dipyrrinato)Zn(II) complexes (ZnDIPY) against BODIPYs is a bottom-up design of materials via facile coordination with metal, and recently some supramolecular systems were developed utilizing this priority[1]. However, a ZnDIPY is inferior to the corresponding BODIPY in fF, which degrades the value of a ZnDIPY as photonic materials. In order to improve fF of ZnDIPY, we developed heteroleptic ZnDIPYs, in which two dipyrrin ligands have different excitation energies[2]. The precursor dipyrrin ligands were prepared by deboration from the corresponding BODIPYs using t-BuONa. Homoleptic ZnDIPY 1a, 1b, 2 and heteroleptic ZnDIPY 3a, 3b were synthesized by treatment Zn(OAc)2 with corresponding dipyrrin ligands. Formation of heteroleptic ZnDIPYs was confirmed by X-ray crystallographic analysis. fF of heteroleptic 3a was very high, 0.76 in toluene, which is superior to the corresponding homoleptic 1a (0.28) and 2 (0.72). This is more prominent in CH2Cl2: heteroleptic 3a showed even higher fF (0.53) than homoleptic 1a (0.00) and 2 (0.31). On the other hand, heteroleptic 3b exhibited only a faint fluorescence both in toluene (0.08) and CH2Cl2 (0.03). The electronic structures of ZnDIPYs were also examined by DFT calculation and cyclic voltammetry, and revealed that both first oxidation and reduction occur on dipyrrin ligand 2 in 3a, whereas the first oxidation occurs on ligand 1b, and the first reduction occurs on ligand 2 in 3b. The superiority and inferiority of fF in heteroleptic complexes can be explained by formation of non-emissive charge-separated states (CS) from p-p* excited states. In heteroleptic 3a, CS was effectively suppressed compared to the corresponding homoleptic complexes, whereas CS was promoted in 3b, the reason of which is that the energy of CS depends on the oxidation and the reduction potential of two dipyrrin ligands. The results indicate that the appropriate adjustment of oxidation and reduction potential effectively enhanced the fF of heteroleptic ZnDIPYs.

[1] H. Maeda, M. Hasegawa, T. Hashimoto, T. Kakimoto, S. Nishio, T. Nakanishi, J. Am. Chem. Soc., 2006, 128 , 10024–10025. [2] S. Kusaka, R. Sakamoto, Y. Kitagawa, M. Okumura, H, Nishihara, Chem. Asian. J., in press.

Keywords: Dipyrrin, Fluorescence, Zinc

MS.A4.P.184 Green Luminescence of a New Terbium(III) Binuclear Complex Marcelo G. Lahoud,a Lippy F. Marques,b Cecília C. P. da Silva,c Javier A. Ellena,c Marian R. Davolos,a Regina C. G. Frem,a aInstitute of Chemistry, Univ. Estadual Paulista-UNESP, Araraquara, (Brazil). b Department of Chemistry-ICE, Universidade Federal de Juiz de Fora-UFJF, Juiz de Fora (Brazil). cInstitute of Physics of de São Carlos, Universidade de São Paulo-USP, São Carlos (Brazil). E-mail: [email protected] The rare earth compounds have been intensively investigated in relation to their potential applications as luminescent materials [1]. However, their low luminescence efficiency can be overcome by some kind of coordination with ligand where it transfers energy to the metal through the antenna effect [2]. Within this context, the aim of this work is the synthesis and characterization of a Tb3+ complex containing succinate (suc2-) and 3,5-dicarboxypyrazolate (dcpz2-) ligands and the investigation of the luminescent properties. The compound [Tb2(dcpz)2(suc)(H2O)8].(H2O)2 was obtained from the reaction carried out in aqueous solution at room temperature. The infrared vibrational spectrum showed that both the ligands are present in the coordination sphere (Dndcpz2- = nasCOO - nsCOO = 266 cm-1; Dnsuc2- = 86 cm-1). Single-crystal X-ray diffraction study revealed that the complex is a binuclear species, consisting of two terbium(III) ions, a succinate anion, two pyrazolic ligands, eight coordinated water molecules and two crystallization water molecules. The coordination number of Tb3+ is nine and the coordination polyhedron can be best described as a tricapped trigonal prism (see Figure 1). The Tb3+ emission occurs both from a characteristic f → f excitation and also from intraligand transitions, the later indicating ligand → Tb3+ energy transfer. The broad excitation band at ~300 nm can also be assigned to the f → d Tb3+ transitions. From intraconfigurational excitations, the Tb3+ emission bands observed in the spectrum at 489, 546, 584, 621, 650, 666 and 679 nm are attributed to the 5D4 → 7F6-0 transitions, respectively. Thermal analysis showed that the compound release all coordinated water molecules at ~ 200 °C leading to a intermediate which is stable up to ~ 300 °C. The consecutive thermal decompositions suggest total destruction of the structure with loss of the organic ligands.

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Poster Sessions as examples. On the one hand, the EPR method allows to monitor directly paramagnetic transition-metal sites in the material. On the other hand, one can add spin probes (nitroxide molecules) to the reaction mechanism. These probes function as EPR spy molecules that can monitor the changing structure of the material during the synthesis process. [1]S. Velu, L. Wang, M. Okazaki, K. Suzuki, S. Tomura, Micropor. Mesopor. Mat., 2002, 54, 113-126. [2]L. Wang, A. Kong, B. Chen, H. Ding, Y. Shan, M. He, J. Mo. Catal. A: Chem., 2005, 230, 143-150.

Keywords: EPR, spin probe, Cu-PMOs

Figure1. ORTEP diagram of [Tb2(dcpz)2(suc)(H2O)8].(H2O)2.

MS.A4.P.186

[1] K. Binnemans, Chem. Rev,. 2009, 109, 4283–4374. [2] G. F. de Sá, O. L. Malta, C. de Mello Donegá, A. M. Simas, R. L. Longo, P. A. Santa-Cruz, E. F. da Silva Jr., Coord. Chem. Rev., 2000, 196, 165–195.

An Unexpected Behavior in FeIII Complexes: LIESST Effect in Oxalate-Based Multifunctional Materials. Photophysical and Magnetic Studies

Keywords: terbium, O-donor ligands, luminescence

M. López-Jordà,a M. Clemente-León,a E. Coronado,a A. Tissot,b A. Hauser,b C. Desplanches,c H. Wang,c J.-F. Létard,c aICMol, Universitat de Valencia, Valencia, (Spain). bDépartement de Chimie Physique, Université de Genève, Genève (Switzerland). cICMCB, CNRS, Université de Bordeaux, Pessac (France). E-mail: [email protected]

MS.A4.P.185 Obtaining Information About NanoPorous Materials from Spin Probing and EPR Feng Lin,a,b Pegie Cool,b Sabine Van Doorslaer,a aDepartment of Physics, University of Antwerp, Antwerp,(Belgium). bDepartment of Chemistry, University of Antwerp, Antwerp, (Belgium). E-mail: Feng. [email protected] Nanoporous materials are of great importance for applications in the field of sorption and catalysis. Since the 90’s, there has been an explosive growth in the development of new ordered mesoporous silicas (pore diameters between 2 and 50 nm). However, for sorption and catalytic applications it is necessary to activate the mesoporous silica structures. One of the most effective ways is to incorporate organic functionalities directly into the silica structure. Numerous potential applications exist for hybrid organic-inorganic porous materials, e.g. in the chemical industry (catalysis), in environmental applications (metal scavenging) and in medical applications (controlled drug release). This type of hybrid materials can be prepared via different routes whereby the functional organic groups are integrated in a different way into the silica network. Moreover, besides its inorganic silica matrix and organic functionalities, incorporation of additional metal atoms in the framework is also viable for producing solid acid/base or redox catalysts. Therefore, combining organic groups and active sites of metal atoms in the hybrid frameworks with ordered porosity, a desirable catalyst could be put into practice. Copper complexes have long been found to be effective catalysts and are used in a wide range of reactions. To date, copper-containing mesoporous molecular sieves (Cu-MMS) such as Cu-MCM-41[1] and Cu-SBA-15[2] have been successfully synthesized and show efficient catalytic performance in the liquid phase oxidation of aromatic compounds. Although, Cu-containing mesoporous materials have received considerable attentions, only a few Cu-containing periodic mesoporous organosilica (PMO) have been reported. Many problems need to be overcome, including the difficulty of removing the template, the loss of the ordered mesoporous structure and the morphological changes that occur with respect to loading. Furthermore, the coordination, dispersion and aggregation degree of copper species in mesoporous silica materials are still not well understood. Here, we show that electron paramagnetic resonance (EPR) is an excellent tool to obtain mechanistic insight into these porous materials, using mesoporous silica and periodic mesoporous organosilica (PMO)

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Multifunctional materials that combine two (or more) physical properties of interest are one of the most promising developments in molecular magnetism. Thus, a wise choice of the constituent molecules could allow the appearance in the same compound of an unusual combination of physical properties, or even a mutual interplay of the properties involved. A switchable multifunctional material can be obtained if a responsive network can influence the properties of the other network. A possible strategy to reach this goal and to prepare a switching magnet is the insertion of spin crossover complexes into oxalate-based extended networks [1]. Spin crossover complexes are capable of switching between two states of different size: low spin (LS) and high spin state (HS). The LS state is stable at low temperature, but it can be transformed to the metastable HS state by irradiation – through the well-known LIESST effect– (light-induced excited spin state trapping), much more common for FeII complexes than for FeIII ones. FeIII spin-crossover complexes have been used as templating cations to grow anionic bimetallic oxalate-based networks. Thus, [Fe(sal2trien)]+ complexes and derivatives have led to different compounds with 2D or 3D oxalate-based structures [1]-[4]. The compounds [Fe(sal2-trien)][MnCr(ox)3] ·S (S = CH2Cl2 1,CHCl3 2, CH2Br2 3, CHBr3, 4) present a 2D honeycomb anionic layer and coexistence of magnetic ordering and photoinduced spin-crossover (LIESST effect) [5]. Furthermore, the presence of different solvents causes changes in the distance between the oxalate layers (i. e. chemical pressure on the inserted spin-crossover cation) that modify the spin crossover properties of the inserted cation. This very rare and unexpected property for a FeIII spin-crossover compound has been attributed to the strong distortion exhibited by the metastable HS state. To understand these phenomena, spectroscopic measurements have been carried out on [Ga0.98Fe0.02(sal2-trien)][MnCr(ox)3]·S single crystals. In order to increase the interplay between the two properties, other compounds presenting 3D bimetallic oxalate-based networks have been studied as the magnetic ordering of 3D networks is very sensitive to the changes of size of the inserted cation. Preliminar results indicate that [Fe(5-Cl-sal2-trien)][MnCr(ox)3]·0.5(MeNO2), 5, present an unusual 3D chiral network [4], and a LIESST effect. [1] M. Clemente-León, E. Coronado, C. Martí-Gastaldo, F. M. Romero, Chem. Soc. Rev., 2011, 40. [2] M. Clemente-León, E. Coronado, M. López-Jordà,

G. Mínguez Espallargas, A. Soriano-Portillo, J. C. Waerenborgh, Chem. Eur. J., 2010, 16. [3] M. Clemente-León, E. Coronado, M. López-Jordà, Dalton Trans., 2010, 39. [4] M. Clemente-León, E. Coronado, M. López-Jordà, J. C. Waerenborgh, Inorg. Chem., 2011, 50. [5] M. Clemente-León, E. Coronado, M. López-Jordà, C. Desplanches, S. Asthana, H. Wang, J. F. Létard, Chem. Sci., 2011, 2.

Keywords: materials

Spin-crossover,

LIESST-effect,

multifunctional-

MS.A4.P.187 Metallo-Supramolecular Assemblies: New Chemistry of Cyclotricatechylene Jonathan Loughrey, Michaele Hardie, Malcolm Halcrow. School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK. E-mail: cmjjl@ leeds.ac.uk Cyclotricatechylene (CTC, 1), the tris-catechol analogue of the important bowl shaped cavitand cyclotriveratrylene (CTV, 2), is readily prepared via exhaustive demethylation of CTV using BBr3. [1] Little studied to date, this important molecular scaffold has the potential to demonstrate a functionalised upper-rim[2] and may also form clathrates in varying stoichiometries and bilayer arrangements.[3] Recently, CTC6- has been shown to form extended inorganic networks in clusters using VO2+ and Ca2+ cations[4] and a highly symmetric tetrahedral cage using Cu2+ and Na+ cations.[5] We hereby report our results to date regarding complexation at the upper rim of CTC using a variety of metal-ancillary ligand combinations. Owing to the interesting ability of dioxolene ligand systems to display the reversible oxidation/reduction series catecholate(2-)/semiquinone(1-)/quinone(0) our interest is in forming the first homologous series of complexes of CTC6- to CTC3- and characterising the different redox states where appropriate. We have prepared and characterised a number of such complexes utilising bipyridyl derivatives as ancillary ligands as these have previously been shown to participate in electronic transitions of LL`CT in character due to their empty and highly accessible π* orbitals.6 Our results (UV-vis and IR) offer evidence for intense charge transfer across the metal centres {Pd(II), Pt(II) and Cu(II)}, utilising different groups appended to the 4,4` position of the 2,2`-bipyridyl ancillary ligand. We have also performed voltammetric analysis (CV and DPV) on the complexes synthesised and found some reversibility in each of the three catecholate(2-) ± semiquinone(1-) oxidation/reduction processes, however these currently appear poorly resolved. Furthermore, owing to the interesting electronic nature of CTC, we also report its ability to crystallise as the first recorded cavitand electronic donor : acceptor complexes using tetracyanoethylene (TCNE) and tetracyanoquinodimethane (TCNQ).[7]

Fig. 1. Cyclotricatechylene; 1, Cyclotriveratrylene; 2. [1] A. Chakrabarti, H.M. Chawla, G. Hundal, N. Pant, Tetrahedron, 2005, 63, 12323-12329. [2] D. S. Bohle, D. Statsko, Chem. Commun., 1998, 568-568. [3] C. J. Sumby, M. J. Hardie, Acta Cryst. Sect. E, 2007, 63, o1537-o1539. [4] B. F. Abrahams, N. J. FitzGerald, R. Robson, Angew. Chem., Int. Ed., 2010, 49, 2896-2899. [5] B. F. Abrahams, B. A. Boughton, N. J. FitzGerald, J. L. Holmes, R. Robson, Chem. Commun., 2011, 46, 7404-7406. [6] J. Best, I. V. Sazanovich, H. Adams, R. D. Bennett, S. Davies, A. J. H. Meijer, M. Towrie,

S. A. Tikhomirov, O. V. Bouganov, M. D. Ward, J. A. Weinstein, Inorg. Chem., 2010, 49, 10041-10056. [7] J. J. Loughrey, C. A. Kilner, M. J. Hardie, M.

A. Halcrow, Supramol. Chem., 2012, 24, 2-13.

Keywords: Cavitand, Redox, Charge-Transfer

MS.A4.P.188 Synthesis and Studies of Novel 5-Substituted Tris-(9Oxidophenalenone) Aluminium Complexes Andrea Magria, Bernhard Schaefera, Mario Rubena,b. aInstitute of Nanotechnology, Karlsruhe Institute of Technology, EggensteinLeopoldshafen (Germany).b Université de Strasbourg, Institute de Physique et Chimie des Matériaux de Strasbourg (France). E-mail: [email protected] Design and synthesis of novel (in)organic materials with better electron transporting capability is an important pre-request for the realisation of efficient organic light emitting device[1]. In this regard we envisioned to synthesize novel organic ligands based on 9-Hydroxyphenalenone by introducing appropriate substituents at the position 5. Variety of substituents with electron donating, withdrawing and conformation directing capacities were introduced by adopting a Suzuki coupling procedure followed by a ring closing reaction [2]. The aforementioned ligands were complexed with aluminium salts. To check the possibility of incorporating the novel molecular frameworks in optoelectronic devices, electronic, photophysical properties and sublimation of the aluminium complexes were investigated. [1] L.S. Hung, C.H. Chen, Materials Science and Engineering, 2002, 39, 143–222. [2] R.C. Haddon, R. Rayford, A.M. Hirani, J. Org. Chem, 1981, 46, 4587-4588.

Keywords: Tris-(9-oxidophenalenone) aluminium electron transport materials, light emitting devices

complex,

MS.A4.P.189 Novel croconate- and anilate-based Molecular Materials with Conducting and/or Magnetic Properties Maria Laura Mercuri, Matteo Atzori,a Flavia Artizzu,a Paola Deplano,a Angela Serpe,a Elisa Sessini,a Samia Benmansour b and Carlos J. Gómez-García,b. aDipartimento di Scienze Chimiche e Geologiche, Università di Cagliari, Monserrato, (Italy). bInstituto de Ciencia Molecular, Universidad de Valencia, Paterna, (Spain) E-mail: [email protected] Over the three last decade Coordination Chemistry has played a key role in the design of supramolecular architectures whose physical properties and dimensionality are strongly dependent on the chemical nature of their molecular building blocks. Among them the d-transition metal complexes of the oxalate dianion have produced materials showing technologically interesting physical properties such as molecular ferri- and ferromagnets and in combination with organic radicals of the tetrathiafulvalene (TTF) family, paramagnetic (super) conductors and ferromagnetic conductors, the last significant advance in this field. [1] An overview of the most significant results obtained by playing with chiral d-transition metal complexes of selected ligands, showing coordination modes and bite parameter similar to the oxalate, such as the croconate (C5O5)2- and the anilate (X2C6O4)2- dianions, shown below, is reported in this communication.

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Poster Sessions

Poster Sessions driven rotation in the copper(I) state with a potential shift (DE°′ = 0.14 V) was analyzed by electrochemical measurements of the complex in the solution state. The rotor could be reset to the initial state by heating, thereby completing the cycle and enabling repeated operation fuelled by light energy. A significant redox potential shift associated with the copper(II)/(I) transition accompanied the rotation, thereby providing a new type of molecular signaling system.

Scheme 1. M(croconate)3 (left) M(anilate)3 (right) MIII=Fe, Cr

A novel family of paramagnetic conductors, a rare example of ferromagnetic coupling via H-bonds [2] and a novel class of layered molecular magnets showing ferrimagnetic ordering will be discussed in detail. [1] E. Coronado and P. Day, Chem. Rev., 2004, 104, 5419. [2] a) M. Atzori, E. Sessini, F. Artizzu, A. Serpe, P. Deplano, C. Gómez-García, C. Gimenez-Saiz and M. L. Mercuri, et al., Inorg. Chem., 2012, doi: 10.1021/ic300331e; b) M. L. Mercuri, P. Deplano, L. Pilia, A. Serpe, F. Artizzu, Coord. Chem. Rev., 2010, 1419, doi: 10.1016/j.ccr.2009.10.002.

Keywords: multifunctional molecular (super)conductors

materials,

molecular

magnets,

Figure 1. Conceptual diagram showing the photo- and heat-driven pyrimidine ring rotational isomerization. [1] Nomoto, K.; Kume, S.; Nishihara, H. J. Am. Chem. Soc. 2009, 131, 3830– 3831. [2] Kume, S.; Nomoto, K.; Kusamoto, T.; Nishihara, H. J. Am. Chem. Soc. 2009, 131, 14198–14199. [3] Kume, S.; Nishihara, H. Chem. Commun. 2011, 47, 415–417. [4] Kume, S.; Nishihara, H. Dalton Trans. 2011, 40, 2299– 2305. [5] Nishikawa, M.; Nomoto, K.; Kume, S.; Inoue, K.; Sakai, M.; Fujii, M.; Nishihara, H. J. Am. Chem. Soc. 2010, 132, 9579–9581.

Keywords: Copper, Photoisomerization, Redox

MS.A4.P.191 Cu(II)/(I) Redox Potential Switching Driven by Light-Induced Coordinated Ring Rotation Michihiro Nishikawa,a Kuniharu Nomoto,a Shoko Kume,a, Hiroshi Nishihara,a aDepartment of Chemistry, School of Science, The University of Tokyo, Tokyo, (Japan). E-mail: [email protected] Multi-stable molecules that are capable of intramolecular structural or chemical transitions form a subclass of molecules useful in nanotechnology applications. We have focused on simple copper complexes that include asymmetric pyrimidines, such as 4-methyl-2(2′-pyridyl)pyrimidine, which can undergo structural transitions based on chemical energy supplied by adding redox reagent solutions.[15] The structural transitions modulate the electrode potential,[1] and can manipulate intramolecular electron transfer within a redox array comprising a copper center and a bound ferrocene moiety.[2] We here describe the first metal complex system in which electronic signals can be repeatedly extracted by converting bistable states related to an intramolecular ligand rotational motion, which is fuelled by visible light. The molecular structure for relating an electron transfer and a motion consists of a copper center and a coordinated asymmetric pyrimidine derivative, whose rotational isomerization causes an electrochemical potential shift. To harness light energy effectively through metal-to-ligand charge transfer (MLCT) excitation, we prepared a simple copper(I) complex coordinated by a 4-methyl-2-(6′methyl-2′-pyridyl)pyrimidine and a bulky diimine. The thermodynamic and kinetic parameters of redox and rotational reactions were analyzed by cyclic voltammograms at variable temperatures, by considering four stable isomers related to copper(II)/(I) states and rotational isomeric states. The key feature of this compound is that the rotation is frozen in the copper(I) state (rate constant for the rotation, kIi→o = 10-4 s–1), but is active in the copper(II) state kIIi→o =10-1 s-1) at 203 K. The compound makes a bypass route to the isomeric metastable copper(I) state, via a tentative copper(II) state formed by photoelectron transfer (PET) in the presence of a redox mediator, decamethylferrocenium ion (DMFc+), or upon a partial oxidation of the complex. Light- and heat-

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MS.A4.P.192 Novel HOMO-LUMO Band Overlapped Molecular Conductors Based on Pt(dmit)2 Mitsushiro Nomura,a Akiko Tajima,a Hengbo Cui,a Abdel Jawad Majed,a Takao Tsumuraya,a,b Tsuyoshi Miyazaki,b Yugo Oshima,a Reizo Katoa, aCondensed Molecular Materials Laboratory, RIKEN (Japan), bNational Institute for Materials Science (Japan). E-mail: [email protected] (M.N.), [email protected] (R.K.) Most anion radical salts of the Pd-dithiolene complex [Pd(dmit)2] (dmit = 1,3-dithiol- 2-thione-4,5-dithiolate) are Mott-insulators at ambient pressure. In the Pd(dmit)2 system with the small HOMO-LUMO energy gap, the strong dimerization induces a HOMO-LUMO band inversion and provides 2D electronic structures associated with a halffilled HOMO band. The [Pd(dmit)2]2 dimer units form a 2D triangular lattice and then provide interplay between electron correlation and spin frustration.[1] In the Pd(dmit)2 salts with quaternary onium cations, the so-called β- or b’-(R4Z)[Pd(dmit)2]2 (R = Me and Et; Z = N, P, As and Sb), a chemical modification of the R4Z+ cation systematically controls the inter-dimer transfer integrals and thus anisotropy of the triangular lattice. On the other hand, we may control the degree of dimerization, that is, the intra-dimer transfer integrals (tH, tL in Figure below) by Pd/Pt substitution, because an intra-dimer M‒M distance is probably modified. However, to our knowledge, only the example in this series was the b-(Me4N) [Pt(dmit)2]2.[2] Accordingly, we have decided to study structures and physical properties of other Pt(dmit)2 salts with different onium cations R4Z+ including Me4P+, Me4As+ and Me4Sb+. The onium cation salts (R4Z)[Pt(dmit)2]2 (R4Z+ = Me4P+, Me4As+ and Me4Sb+) obtained in this work belong to the b’-forms, whereas the Me4N+ salt is the b-form.[2] The Pt(dmit)2 salts showed weaker dimerization than the Pd(dmit)2 salts. It is notable that the Pt‒Pt bond lengths were well modified by changing the cation; Me4P+ (Pt‒Pt = 3.308 Å), Me4As+ (3.283 Å) and Me4Sb+ (3.232 Å), respectively. In contrast to the Mott-insulating Pd(dmit)2 salts, the b’-Me4Z+ salts of Pt(dmit)2 showed metallic behavior under ambient pressure in the

high temperature region. Furthermore, metal-to-insulator transitions appeared in the temperature range of 150-215 K, suggesting existence of charge-ordered states below the critical temperature. Unlike these Pt(dmit)2 salts, the Pd(dmit)2 salts with the same cations have shown antiferromagnetic long range order at low temperature region.[1] The band structures of these Pt(dmit)2 salts obtained by first-principles calculations indicated overlap of the anti-bonding HOMO and bonding LUMO bands in the b’-Me4P+ and b’-Me4As+ salts, whereas these two bands were separated in the b’-Me4Sb+ salt.

one, respectively. This drop of the transition temperature in spite of the connection of the π-orbital is inconsistent with the result of the previous literature.[1] Therefore, there is a possibility of the existence of antiferromagnetic interaction between adjacent Co-LDH layers. On the other hand, the 2 intercalated Co-LDH shows the mixed state of open (2a) and close (2b) form of DAE intercalated one regardless of the states of starting anions for preparation. However, visible light irradiation to 2b intercalated one indicates the clearly reduction of the high temperature component of the zero field cooled magnetization, which is assigned to the close form intercalated domain as same as the complex of previously reported. These results indicate that the ferromagnetic transition can be controlled by the photoirradiation in the solid state. In the future work, we expect to realize the complex whose ferromagnetic transition temperature can be enhanced or reduced by photoirradiation with specific wave length for a mixed complex with 1 and 2 intercalated Co-LDHs.

[1] R. Kato, Chem. Rev. 2004, 104, 5319. [2] A. Kobayashi et al., J. Mater. Chem. 1991, 1, 827.

Keywords: platinum-dmit, molecular conductor, band structure

MS.A4.P.193 Photocontrollable Multi Step Magnetization in a Co-Layered Double Hydroxide Hirofumi Oosima,a Masaya Enomoto,a Atsushi Okazawa,b Norimichi Kojima,b aDepartment of Chemical Sciences and Technology, Tokyo University of Science, Tokyo (Japan). bDepartment of Basic Science, University of Tokyo, Tokyo (Japan). E-mail: [email protected]. tus.ac.jp Transition metal layered double hydroxides (M-LDHs) provide an excellent opportunity to control their magnetic properties by the selection of metal ion and intercalated anions, which result in various types of magnetisms, such as ferromagnetism, ferrimagnetism, or antiferromagnetism. Especially, the Co-LDHs shows the ferromagnetic transition, whose temperature can be tuned by the interlayer distance and unsaturation degree of intercalated anon. Recently, it was reported that an anionic diarylethene derivative (DAE) was intercalated to a CoLDH as an anion to control its magnetic interaction by the irradiation of light. DAEs underwent a thermally irreversible and fatigue-resistant photochromic reaction. According to the molecular orbital calculation, the π-electron system was divided in the open form of DAE, while that in the closed form was delocalized whole of molecule. The switching from open to close form of DAE anion gave the interaction between adjacent magnetic layers of Co-LDH. Consequently, enhancement of the ferromagnetic transition temperature was observed due to the photoisomerizaton of the intercalated DAE anion. On the basis of this strategy, we have used two types of anionic DAE derivatives 1 and 2 as intercalated molecules to a Co-LDH. Each DAE derivative is changed its structure by photo irradiation with different wave length. Therefore, it is expected that the photo-controllable multi step magnetization can be realized by the coexistence of the several types of DAE as the intercalated anions to the Co-LDH. Firstly, we carry out the individual intercalation of 1 and 2 to the Co-LDHs. In the case of 1 intercalated Co-LDH, the ferromagnetic transition temperature decrease from 17 to 12 K for 1a and 1b intercalated

Scheme 1 [1] H. Shimizu, M. Okubo, A. Nakamoto, M. Enomoto and N. Kojima, Inorg. Chem., 2006, 45, 10240-10247.

Keywords: cobalt layered double hydroxide, anionic diarylethene derivative, ferromagnetism

MS.A4.P.194 A tetrapropionatodirhodium(II) Compound Containing Different Dinuclear Units Josefina Perles†, Pilar Amo-Ochoa†,ǁ, Reyes Jiménez-Aparicio†, M. Rosario Torres‡, †Dpto. de Química Inorgánica. Facultad de Ciencias Químicas. Universidad Complutense de Madrid. Ciudad Universitaria, 28040-Madrid (Spain). ǁPresent address: Dpto. de Química Inorgánica. Facultad de Ciencias. Universidad Autónoma de Madrid. Campus de Cantoblanco. 28049 Madrid (Spain),‡ Centro de Asistencia a la Investigación de Rayos X. Facultad de Ciencias Químicas. Universidad Complutense de Madrid. Ciudad Universitaria, 28040-Madrid (Spain). E-mail: [email protected] Many paddlewheel dirhodium compounds with carboxylate ligands bridging the dimetallic units are known, with a wide variety of architectures constructed by different scientific approaches [1]. Although the majority of these compounds are based on discrete dinuclear units, the dimetallic fragments can be successfully used to achieve an emerging number of coordination polymers with interesting properties [1]. In this communication we describe the singular X-ray structure of a dirhodium(II) complex with propionate as equatorial ligand. The compound was obtained by reaction of the tetrapropionatodirhodium(II) derivative with KBr in the presence of HBF4. The structure of this compound was solved by single crystal X-ray diffraction methods. It consists of a complicated three-dimensional

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Poster Sessions arrangement that contains different kinds of dirhodium species. Thus, the compound has a formula K[Rh2(O2CEt)4(Br)0.5]2[Rh2(O2 CEt)4(H2O)2] and displays [Rh2(O2CEt)4]2 dimeric units joined by O-Rh interactions, in which the oxygen atom from the neighbour dirhodium unit occupies the axial position of a paddlewheel fragment and conversely. The two remaining axial positions of these tetramers are occupied by shared bromide ligands to create a bidimensional {[Rh2(O2CEt)4]2Br2}∞ network. In the second type of dirhodium units [Rh2(O2CEt)4(H2O)2], the axial positions are occupied by water molecules. The [Rh2(O2CEt)4]2 fragments and one half of the [Rh2(O2CEt)4(H2O)2] species form a three-dimensional framework through K-Br and O-K interactions. The remaining half of the [Rh2(O2CEt)4(H2O)2] molecules are located in the channels formed by the three-dimensional arrangement. This structure can be simplified as indicated in Figure 1.

a) Section of the pillared structure in 1 with disordered perchlorate and water removed for clarity; b) the kagome lattice in 1

Figure 1: Simplification of the network found in compound K[Rh2(O2CEt)4(Br)0.5]2[Rh2(O2CEt)4(H2O)2]. [1] Cotton, F. A.; Murillo, C. A. Walton, R. A. Multiple Bonds between Metal Atoms. Multiple Bonds Between Metal Atoms, 3er Ed. F. A. Cotton, A. Murillo, R.A. Walton 2005, 465-590.

Keywords: paddlewheel, dirhodium, X-ray structure

MS.A4.P.195 Multifunctional MOFs through carbon capture Jason Price,a Tony Keene,b Michael Murphy,b Natasha Sciortino,b Peter Southon,b Cameron Kepert,b aAustralian Synchrotron, Clayton, (Australia). bSchool of Chemistry, The University of Sydney, Sydney (Australia). E-mail: [email protected] We have combined the properties – carbon capture, zero thermal expansion and molecular magnetism, along with a singlecrystal to single-crystal transformation – in a single multifunctional nanoporous MOF, [Cu3(bpac)3(CO3)2](ClO4)2∙H2O, 1∙H2O (where bpac is 4,4′-bipyridylacetylene). The formation of compound 1∙H2O is an example of a modified Solvay process where CO2 is absorbed from the air and fixed as hydrogencarbonate by ammonia solution. Evaporation of the ammonia allows the copper ions to be chelated by the carbonate. The kagome lattice in 1∙H2O is a much sought-after topology in molecular magnetism: antiferromagnetic interactions in such a layer would lead to spin frustration and would be an excellent probe in the physics of such phenomena.[1]

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Compound 1∙H2O consists of [Cu3(CO3)2]2+ kagome layers in the ab-plane bridged by bpac through the Cu atoms in the c-axis. Disordered ClO4− anions reside in the hexagonal pores of the kagome layer and the voids between alkynes with a water molecule between the perchlorates. Variable temperature single crystal X-ray diffraction studies on this robust system allow us to remove the water molecule in situ on heating above 300K to yield 1. On cooling the desolvated crystal we retain the original lattice until temperature drops below 150K where the crystal undergoes a phase transition that leads to a doubling of the c-axis. Unit cell collections between 100-400-150 K show uniaxial negative thermal expansion in the c-axis in 1∙H2O with αc = −2.2(8) × 10−6 K−1 for the region 100−275 K (where αx = dx/xdT) and in 1 with αc = −2.1(8) × 10−6 K−1 for the region 400−175 K. In both 1∙H2O and 1, a large positive thermal expansion is seen in a and V with coefficients of +44(2) and +86(3) × 10−6 K−1, respectively, for 1∙H2O and +47(2) and +92(4) × 10−6 K−1, respectively, for 1. This work along with the effects of anion substitution will be presented. [1] S. Yan, D. A. Huse, S. R. White, Science, 2011, 332, 1173-1176.

Keywords: Multifuctional, MOF, Kagome

MS.A4.P.196 New Functional Hybrid Materials Based on Template VPO Cage Supported TM Ions Jabor Rabeah,a Angelika Brückner,a aLeibniz Institut for Catalysis e. V. University of Rostock. Rostock, (Germany). E-mail: jabor.rabeah@ catalysis.de New organic–inorganic hybrid materials based on the utility of [(V2O3)2(RPO3)4⊂F]— cage (VPF) as building block supported by different transition metal ion as a charge compensating have been designed, synthesized and characterized by single crystal XRD, such as Ni(2,2-bipy)3[(V2O3)2(tBuPO3)4,F].CH3CN, [Co(NCCH3)6] [(V2O3)2(PhPO3)4,F]2 and [Zn(NCCH3)4(OH2)2] [(V2O3)2(PhPO3)4,F]2. Figure 1. Compared to traditional procedures for preparation of VPO clusters, this has been achieved by a rather simple preparation protocol using our previously developed [Ag(NCCH3)3][(V2O3)2(RPO3)4⊂F] complex [1] via metathesis. In contrast to most mixed-metal organophosphonates, these compounds are soluble and stable in polar organic solvents. Therefore, the intact cage structure in solution has been easily proved by

multinuclear NMR (1H, 19F, 31P and 51V) and EPR spectroscopy upon one-electron reduction. Moreover, the magnetic interaction between the unpaired spins in the new TM-VPF compounds has been preferentially investigated by electron paramagnetic resonance (EPR). The new approach to prepare new hybrid materials is not restricted to specific compounds but opens access to a wide variety of VPF cage with other TM ions. Varying the TM ions in different valence states and with ligand spheres of different geometric constraint, could open a wealth of opportunities in solid-state chemistry to synthesize materials with exciting structural, redox and/or magnetic properties.

thermal, or pressure memories at the nanometer scale. To be useful in practice, a demanding set of material requirements must be met, such as room-temperature operation, control of the hysteresis with on demand, non-destructive writing, and readout of the information. Modulation of Tc and cooperativity has been achieved by applying external and / or chemical pressure. Particle size, isomorphic substitution of iron(II) SCO ions by inert SCO ions (ie. nickel(II), cobalt(II), etc) and engineering intermolecular interactions are common means to tune chemical pressure. Furthermore, porous coordination polymers (PCPs) have enabled an alternative strategy to enhance the ST features on the basis of host-guest chemistry of the framework. Here we present an example of drastic enhancement of cooperativity in the 3D SCO-PCPs {Fe(pyrazine)[M(CN)4]} (M = Pd(II) and Pt(II)). Inclusion of thiourea molecules capable of interacting with the organic pillar ligands and the unsaturated metal coordination sites through weak intermolecular interactions have lead to the clathrate compounds formulated {Fe(pz)[Pt(CN)4]}·0.5(CS(NH2)2)(1) and {Fe(pz) [Pd(CN)4]}·1.5H2O·0.5(CS(NH2)2) (2). These 3D porous coordination polymers exhibit unprecedented spin transitions accompanied by large thermal hysteresis cycles ca. 60 K wide.[1] [1] F. J. Muñoz-Lara, A. B. Gaspar, D. Aravena, E. Ruiz, M. C. Muñoz, M. Ohba, R. Ohtani, S. Kitagawa, J. A. Real, Chem. Commun. 2012, CCCOM-02-2012-031048, (accepted).

Keywords: spin crossover, coordination polymers, porosity

Figure 1. Crystal structure of [Zn(OH2)2(NCCH3)4] [(V2O3)2(PhPO3)4,F]2 showing the fluoride anion (with van der Waals radius of the atom) in the centre of the cage. [1] J. K. Jabor, R. Stösser, N. H. Thong, M. Meisel, B. Ziemer, Angew. Chem., Int. Ed. 2007, 46, 6354.

Keywords: vanadium phosphonate cage, hybrid materials, redox active

MS.A4.P.197 Enhanced Bistability by Guest Inclusion in Fe(II) Spin Crossover Porous Coordination Polymers J. A. Real,a F. J. Muñoz-Laraa, M. C. Muñozb , A. B. Gaspara, M. Seredyuka, Z. Arcís-Castilloa, T. Romero-Morcilloa, E. Ruizc, D. Aravenac, S. Kitagawad and M. Ohba,e aInstitut de Ciència Molecular, Universitat de València, Spain. bDepartament de Física Aplicada, Universitat Politècnica de València, Spain.c Departament de Química Inorgànica and Institut de Recerca de Química Teòrica i Computacional, Universitat de Barcelona, Spain. dInstitute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Japan. e Department of Chemistry, Faculty of Science, Kyushu University, Fukuoka, Japan. E-mail: [email protected] In the search for new advanced materials, sensory and memory are important functions that require switchable components. Iron(II) spincrossover (SCO) complexes have been demonstrated to be particularly suitable to this end. They reversibly switch between a diamagnetic (S = 0) low-spin state (LS) and a paramagnetic (S = 2) high-spin state (HS) under an external stimulus like temperature, pressure, magnetic field or light. A sharp variation of the structure, magnetism, colour, or dielectric constant of the system in response to these stimuli may occur in the solid state. Furthermore, hysteresis may accompany this first order spin transition (ST) when the structural changes are transmitted cooperatively through the whole solid. Due to their switching properties SCO materials are potentially useful for rewritable optical,

MS.A4.P.198 Quantum Yield of a Pr(III) Complex Derived of a Polyoxaaza Ligand Sara Luisa Rodrígueza, Perla Elizondoa, Nancy Péreza, Enrique Garcíab, Esther Carbonellb. aUniversidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, San Nicolás de los Garza, N. L, (México). b Institute for Molecular Science, University of Valencia, Valencia, (Spain). E-mail: [email protected] The luminescence quantum yield of the diaqua-[tris(nitrate)]bis[2,6-bis(2-formylphenoxymethyl)pyridine]praseodymium(III) complex was measured by the optically dilute method [1], [2]. Solutions of the complex and quinine sulphate (as standard) were prepared in 2, 4, 6, 8 and 9x10-5 mol L-1 concentration in acetonitrile. The complex was synthesized previously by direct reaction mixing Pr(NO3)3.6H2O salt and 2,6-bis(2-formylphenoxymethyl)pyridine (L) solutions, and was characterized by elemental analysis, infrared spectroscopy and by X- ray diffraction single crystal [3]. The refraction index as well as absorption, excitation- emission spectra were measured for each solution. The luminescence intensity of the transition 3P0→3F4 decreased as the concentration of the complex in the solution increased, it may occur due to energy deactivation, caused by inelastic collisions of molecules. Finally, the quantum yield was determined considering the values of the refraction index, absorption and luminescent intensity of the transition most sensible. According to the emission, the luminescent intensity is more strong in the complex that in the starting Pr(III) salt, indicating that L participate effectively in the transfer energy to the Pr(III). With respect to the results, the complex shows potential application for the development of luminescent materials.

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Poster Sessions Acknowledgments This work is supported by the Australian Research Council. HSS acknowledges receipt of an Australian Postgraduate Award. [1] A. Grosjean, N. Daro, B. Kauffmann, A. Kaiba, J.-F. Létard and P. Guionneau, Chem. Comm., 2011, 47, 12382-12384. [2]. T. M. Ross, B. Moubaraki, S. M. Neville, S. R. Batten and K. S. Murray, Dalton Trans. 2012, 41, 1512-1523.

Keywords: Multifunction, Spin-Crossover, Redox

MS.A4.P.200

[1] J. Demas, G. Crosby, J Phys Chem US, 1971, 75, 991-1024. [2] S. Petoud, G. Muller, E. Moore, J. Xu, J. Sokolnicki, J. Riehl, et al. J Am Chem Soc, 2007, 129, 77-83. [3] S. Rodríguez, L. Garza, S. Bernès, P. Elizondo, B. Nájera, N. Pérez, Polyhedron, 2010, 29, 2048-2052.

Keywords: quantum yield, luminescent, lanthanide complex

MS.A4.P.199 Spin-Crossover In 1D Ferrocene-1,2,4-Triazole Metal(II) Complexes Hayley S. Scott,a John D. Cashion,a Ayman Nafady,a Alan M. Bond,a Boujemaa Moubaraki,a Suzanne M. Neville,a Stuart R. Batten,a Keith S. Murray,a aSchool of Chemistry, Monash University, Clayton, VIC 3800, Australia. E-mail: [email protected] 1D spin crossover (SCO) complexes of the [FeII(1,2,4(R)-triazole)3] (anion)2 type have been long know for their wide room temperature thermal hysteresis loops (memory) and potential for applications, with the crystal structure of one member, [FeII(NH2trz)3](NO3)2·2H2O only recently being reported by Guionneau et al.[1] As part of a program aimed at making bifunctional FeII SCO materials,[2] particularly those having redox/electron transfer as the second function, we have made the new ferrocene-triazole ligand ATF ([(4H-1,2,4-triazol-4-yl)amino] methylferroene), (1), shown (Fig 1a), and a series of MII complexes of this ligand with emphasis on FeII. Polynuclear 1D-chain complexes [FeII(ATF)3](ClO4)2 (2), [FeII(ATF)3](Br)2 (3), and [NiII(ATF)3](ClO4)2 (4) were formed as powders that could not be crystallised thus far, while crystals of a mixed ATF/NCS-bridged CuII polymer [CuII(ATF)2(NCS)](ClO4) (Et2O)1/2(MeCN) (5) gave the structure shown below (Fig 1b). Magnetic, Mössbauer and solid state cyclic voltametric data on the FeII compounds will be discussed. Thus far, SCO has not been achieved though the Mössbauer data show interesting temperature dependence for doublets of the two Fe sites. a).

Multifunctional Conducting PEDOT thin Films Doped with Magnetic Nanosystems Elisa Sessinia, Carlos Giménez-Saizb, Carlos J. Gómez-Garcíab, Eugenio Coronadob, Maria Laura Mercuri,a aDipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Cagliari, Monserrato, (Italy). bInstitute for Molecular Science, University of Valencia, Valencia, (Spain) E-mail: [email protected] Hybrid organic-inorganic materials based on conjugated polymers constitute state-of-art compounds with recognized technological applications. [1] Among the conducting organic polymers, poly(3,4ethylenedioxythiophene) (PEDOT) possesses several advantageous properties: low oxidation potential, high conductivity, high transparency in thin, oxidized films. [2,3] Much research efforts have been addressed to the development of processing methodologies for the incorporation of magnetic nanostructures into polymeric matrices as thin films. The aim of this work is to integrate two different magnetic nanostructures following different methods tailored on their chemical nature. The in situ chemical oxidation of EDOT monomers using Fe(III) ions, allows the insertion (doping) of anions present in the solution medium into the resulting film. Following this method, the insertion of FeII[CrIII(ox)3]- anions, into matrices of conducting films of PEDOT have been performed. A different approach has been used for the insertion of nanoparticles of Prussian Blue analogues (NiII FeIII cyanide bridged nanoparticles) [4] that have been coated with a commercial blend of PEDOT/PSS (PSS : polystyrenesulfonic acid) conducting polymer. HR-TEM measurements reveal the presence of nanostructures, which are confirmed by magnetic measurements. (Figure 1) A semiconducting behavior have been observed for both materials, but the PEDOT thin film doped with FeII[CrIII(ox)3]- anions show a transition metal-insulator at about 250 K. Particularly interesting is the high conductivity of PEDOT thin film doped with NPs (114 S/ cm at r.t.) that has allowed magneto- resistance measurements at low temperature. The observed change of the conductivity at temperatures below the blocking temperature of the nanoparticles (at 2 K the resistivity increases by a factor above 2 at 8 T), is due to the interplay between the magnetic and conducting lattices. This work has been performed during my stay at ICMol (Valencia, Spain) supported by Regione Autonoma della Sardegna.

b).

Figure 1. Magnetic measurements of PEDOT thin films doped with FeII[CrIII(ox)3]- 2D layers (left) and with nanoparticles (right)

Figure 1. a). Structure of ATF ligand (1) b). Chain structure of [CuII(ATF)2(NCS)] (ClO4)(Et2O)1/2(MeCN) (5). (solvent and anions omitted).

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[1] J. Vailant, M. Lira-Cantu, K. Cuentas-Gallegos, N. Casañ-Pastor, P. GómezRomero, Progress in Solid State Chemistry, 2006, 147-159. [2] B. Groenendaal, G. Zotti, P.-H. Aubert, S.M. Waybright, J.R. Reynolds, Adv. Mater. 2003, 15,

855-879. [3] PEDOT, Principles and Applications of an Intrinsically Conductive Polymer, A. Elschner, S. Kirchmeyer, W. Lövenich, U. Merker, K. Reuter, 2011, CRC Press. [4] D. Brinzei, L. Catala, G. Rogez, A. Gloter, T. Mallah, Inorg. Chim. Acta, 2008, 361, 3931-3936.

Keywords: multifunctional materials, thin films, magnetic conductors

Inorg. Chem. 1999, 38, 4745-4752. [3] R. Chiozzone, A. Cuevas, R. González, C. Kremer, D. Armentano, G. D. Munno, J. Faus, Inorg. Chim. Acta. 2006, 7, 2194–2200.

Keywords: BEDT-TTF, Re complex, π-d interaction

MS.A4.P.202 MS.A4.P.201 Physical Properties of Novel Organic Conductor with Magnetic Re Complexes Fumitoshi Shimotori,a Masaya Enomoto,a Atsushi Okazawa,b Norimichi Kojima,b aDepartment of Chemical Science and Technology, Tokyo University of Science, Tokyo (Japan), bDepartment of Basic Science, The University of Tokyo, Tokyo (Japan). E-mail: jb111804@ ed.tus.ac.jp These days, the design of multifunctional materials has been intensively studied in the field of molecular science. Among them, the coupling between conductivity and magnetism have been attracted much attention in the area of organic conductors as π-d interaction[1]. For example, magnetic field induced superconductivity and localized d-electron ordering by RKKY interaction are successful compounds for π-d interaction system. In order to achieve such property, we employ organic donor molecules and transition metal anions as a conducting π-electron source and localized d-electron spin system. So far, these materials have been investigated by using of 3d metal anions. In this paper, we are focused on 5d metal complexes which are expected to interact with organic donor molecules due to its large d orbital. To investigate novel π-d interaction materials with 5d metal, we employ BEDT-TTF (ET) as an organic donor molecule and [ReX4(ox)]2(ox = C2O4, X = Cl, Br)[2], [3] as a counter anion. Black colored block type single crystals (X = Cl(1), Br(2)) are obtained by electrochemical crystallization. Judging from the X-ray structural analysis, each salt is isomorphous and consists of [ET]4[ReX4(ox)]C6H5CN. Each donor molecule forms β” type layered structure and the analysis of bond lengths suggests that ET molecules have positive charge of +0.5. From electrical resistivity measurements, each salt shows metallic conductivity through low temperature. Then, resistivity of these salts gradually increases along with temperature decreasing. This metalinsulator transition temperature is 154 K (1) and 43 K (2). Magnetic susceptibility at high temperature indicate that each salt has Curie paramagnetism of Re (IV, S = 3/2) and large Pauli paramagnetism by high conductivity. Also, Weiss constant is -7 K (1), -14 K (2), reflects the closest contact of Re complexes whose distances are 4.79 Å (1) and 4.18 Å (2), respectively. These results suggest that π-d interaction is comparatively expected for 2.

Optical Properties of MnPS3 Phases Intercalated by CuII Macrocyclic Complexes Evgenia Spodinea,c , Pablo Fuentealbaa,c, Jorge Manzurb,c, Verónica Paredes-Garcíac,d, Diego Venegas-Yazigi,c,e, aUniversidad de Chile, Facultad de Ciencias Químicas y Farmacéuticas (Chile), bFacultad de Ciencias Físicas y Matemáticas, Universidad de Chile, cCEDENNA, Chile, dUniversidad Andres Bello, Departamento de Ciencias Químicas, eUniversidad Santiago de Chile (USACH), Facultad de Química y Biología. E-mail: [email protected] Lamellar compounds have been the center of many studies because they can be intercalated, forming composites with interesting physical properties. This work presents the optical properties of composites based on the MnPS3 phase intercalated with CuII macrocyclic complexes with Schiff base ligands, obtained by the condensation of 2-hidroxy5-methyl-1,3-benzenedicarbaldehyde with 1,2-phenylenediamine, ethylenediamine, 1,3-diaminoepropane, or 1,3-diamino-2-propanol, of the type [M2L]X2. The composites were obtained by a two step reaction: i) the synthesis of a potassium precursor K0.4Mn0.8PS3, followed by ii) an ionic exchange of the potassium ions by the macrocyclic cationic complex, using microwave radiation, thus obtaining the composites in a few minutes. A study of the solution and solid state UV-visible spectra for the macrocyclic complexes and the composites, respectively, was done in order to see how the optical properties of the MnPS3 phase were modified by the intercalated complexes. The solution spectra of the complexes are dominated by charge transfer bands, which make them highly colored. The solid state spectra of all the composites show an absorption edge at lower energies (2.2- 2.35 eV), as compared with MnPS3 (2.5 eV) and K0.4Mn0.8PS3 (2.8 eV). Keywords: CuII macrocyclic complexes, MnPS3 layered phase, optical properties Acknowledgements The authors thank Financiamiento Basal, FB0807 project FONDECYT 1120001, and PF thanks CONICYT for a national doctoral scholarship 2011.

MS.A4.P.203 New Copper(Ii) Carboxylate Complexes with Amines as Precursors of Nanomaterials Iwona Barbara Szymańska,a Magdalena Barwiołek,a Piotr Piszczek, a Department of Chemistry, Nicolaus Copernicus University, Gagarina 7, 87-100 Toruń, (Poland). E-mail: [email protected]

Figure: structure (a), resistivity (b) and magnetic susceptibility (c) of 2. [1] E. Coronado, P. Day, Chem. Rev. 2004, 104, 5419-5448. [2] R. Chiozzone, R. González, C. Kremer, G. D. Munno, J. Cano, F. Lloret, M. Julve, J. Faus,

Copper is the important material in the advanced metallization for microelectronic and optoelectronic devices. The growth of thin films by Chemical Vapor Deposition (CVD) technique reveals a few advantages, such as: the kinetically controlled deposition process, the conformal coverage, and the possibility of the selective deposition. Therefore, the synthesis and the characterization of new copper coordination compounds, which can be useful as Cu CVD precursors, is still an area of an extensive research.

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Poster Sessions In the case of Cu(I) precursors the disproportionation reaction to metallic copper and copper(II) species take advantage (e.g. for [Cu(b-diketonate)(L)], L = tertiary phosphines, unsaturated silanes, cyclooctadienes [1]). However, copper(I) compounds reveal usually air and moisture sensitivity and they require special conditions during the preparation, the application and the storage. Copper(II) precursors (e.g. [Cu(b-diketonate)2] [1]) are more “user friendly” but an additional reducing agent (e.g. H2) is necessary for the reduction to Cu(0), during a CVD process. The most attractive are compounds, which can combine the advantages of Cu(II) and Cu(I) compounds. We would like to demonstrate that complexes, described below, can be belonging to this class of precursors. Three group of copper(II) complexes with perfluorinated carboxylates of the type: [Cu2{R’NH2}2(m-O2CR)4] (R=CF3, C2F5, C3F7, C4F9, C5F11, C6F13; R’=But, Bus, Et) were obtained in the reaction of copper(II) carboxylate with the amine. This last was generated in situ from the appropriate alkyl isocyanate and immediately coordinated. The analysis of the spectral data were suggested that the complexes were revealed the dimeric structure with bridging carboxylates and axially bonded amines. Thermal properties of complexes [Cu2{R’NH2}2(mO2CR)4] were studied using thermal analysis (TGA/DTA), EI-MS (30300ºC) and temperature-variable IR spectra analysis and they were used for the determination of the preliminary deposition parameters. In CVD experiments, which were performed in the hot-wall reactor, in argon atmosphere, with any additional reducing agent, nanolayers of copper were obtained (Figure 1). Acknowledgements: The authors wish to acknowledge the Polish Ministry of High Education and Science for the financial support grant no N N204 54653

Figure 1 The copper layer deposited using [Cu2(tBuNH2)2(m-O2CCF3)4] (Si(111), Ar, TV = 473 K, p = 1.5 mbar, m = 100 mg, TD = 643 K). [1] T.T. Kodas, M.J. Hampden-Smith, in: The Chemistry of Metal CVD, VCH, Weinheim 1994, pp. 20-30, 175- 238, 242.

Keywords: copper(II) carboxylates, amines, nanomaterials

MS.A4.P.204 Crystal Structures and Gas-Adsorption Properties of OneDimensional Coordination Polymers of Paddle-Wheel Cu(II) Complexes Kiyonori Takahashi,a Norihisa Hoshino,a,b Tomoyuki Akutagawaa,b, a Graduate School of Engineering., Tohoku University, Sendai (Japan). b Institute of Multidisciplinary Research For Advanced Materials (IMRAM), Tohoku University, Sendai (Japan). E-mail: jintokut@mail. tagen.tohoku.ac.jp Molecular motions in crystals have been attracted much attentions from the viewpoint of designs in new functional molecular materials. For instance, the ferroelectricity of (m-FAni+)(dibenzo[18]crown-6)

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[Ni(dmit)2] and huge dielectric responses in [Cu(II)2(adamantane carboxylate)4(DMF)2]•(DMF)2 were associated with the thermal rotations of m-fluoroanilinium (m-FAni+) and DMF molecules within the crystals [1, 2]. On the contrary, novel gas-adsorption properties of the one-dimensional Cu(II)-binuclear coordination polymer crystals have been reported [3]. Herein, we report the preparations, crystal structures, thermal stabilities, and gas adsorption-desorption properties of three new Cu(II)-binuclear coordination polymers of [Cu(mFBA)4(pz)]∞ (1), [Cu(2,3-F2BA)4(pz)]∞ (2), and [Cu(m-MeBA)4(pz)]∞ (3), here m-FBA, 2,3-F2BA, m-MeBA, and pz were m-fluorobenzoate, 2,3-difluorobenzoate, m-methylbenzoate, and pyrazine, respectively. These one-dimensional coordination polymers have the polar ligands, which was designed for the responsible units for the outer stimuli. The crystal structure of 1 was constructed by the one-dimensional [Cu2(m-FBA)4(pz)]∞ chain, where the binuclear Cu2(m-FBA)4-units were bridged by the axial pz ligand. The fluorine atom of m-FBA ligands indicated the orientational disorder (F1- and F2-sites) with the site occupancy factors of 0.5:0.5. The one-dimensional polymers were elongated along the c-axis, and the interchain p-stacking interactions were observed at neighboring m-FBA ligands. The similar onedimensional coordination structure of [Cu2(2,3-F2BA)4(pz)]∞ and orientational disorder of fluorine atoms of 2,3-F2BA ligands were observed in crystal 2. Between the [Cu2(2,3-F2BA)4(pz)]∞ chains, the interchain p-stacking interactions were also achieved. On the contrary, the orientational disorder of methyl-group in [Cu2(m-MBA)4(pz)]∞ chain was not observed in the crystal 3, and the effective interchain interaction was not observed between the chains. The void spaces between the one-dimensional chains of crystals 1, 2, and 3 were 642, 702, and 303 Å3, respectively, where the CH3CN molecules were included in the as-grown crystals and were easily replaced to H2O molecules under the ambient condition. The CO2-gas adsorption of crystal 1 at 195 K showed the stepwise CO2 adsorption-desorption process at ~10-3 and ~10-1 P/P0. At P/P0 ~ 1, three molar of CO2 were absorbed into the channel of 1. Similar CO2-adsorption processes were observed in crystals 2 and 3, where the amount of CO2-adsorption was depended on the void spaces of crystal 1, 2 and 3. The crystal structure and dielectric properties of these crystals will be discussed. [1] T. Akutagawa, H. Koshinaka, D. Sato, S. Takeda, S. Noro, H. Takahashi, R. Kumai, Y. Tokura, T. Nakamura, Nature Mat., 2009, 8, 342. [2] Y. Qiong, K. Takahashi, N. Hoshino, T. Kikuchi, T. Akutagawa, S. Noro, S. Takeda, T. Nakamura, Chem. Eur. J. 2011, 17, 14442. [3] S. Takamizawa, E. Nakata, T. Akatsuka, R. Miyake, Y. Kakizaki, H. Takeuchi, G. Maruta, S. Takeda, J. Am. Chem. Soc. 2010, 132, 3783.

Keywords: Paddle-Wheel Cu(II) complex, Gas Adsorption, Dielectric Response

MS.A4.P.205 Multistep Structural Phase Transitions of Organic-Inorganic Hybrid (CnH2n+1NH3)2CuCl4 Shunsaku Tamura,a Norihisa Hoshino,a,b Tomoyuki Akutagawaa,b a Grad. School of Eng. Tohoku University, Sendai (Japan). bInstitute of Multi-disciplinary Research for Advanced Materials (IMRAM), Tohoku University, Sendai (Japan). E-mail: [email protected]. tohoku.ac.jp Interesting structural and physical properties have been reported in organic-inorganic hybrid of (CnH2n+1NH3)2CuCl4. In the crystals, the two-dimensional inorganic perovskite layer was formed by the cornersharing of [CuCl6]-octahedrons, whereas the organic CnH2n+1NH3 cations were sandwiched by the inorganic layers. The electrostatic and N-H+~Cl hydrogen-bonding interactions connected the organic

cations to inorganic layer. In the crystal of (C2H5NH3)2CuCl4, a multiferroic property coexisting of ferromagnetism and ferroelectricity has been reported [1]. The magnetic property was governed by the two-dimensional Heisenberg ferromagnetic ordering between Cu(II)sites in the two-dimensional perovskite layer, whereas the dielectric property was associated with the motional freedom of ethyl-groups and structural modulation of [CuCl6]-octahedrons. Therefore, the ferroic properties in (CnH2n+1NH3)2CuCl4 system are dominated by both of the organic and inorganic layers. Herein, we examined the structural phase transitions and physical properties of (CnH2n+1NH3)2CuCl4 system by changing in the length of alkyl-chain (n) from n = 4 to n = 18. The single crystals of (CnH2n+1NH3)2CuCl4 (n = 4~10, 12, 14, 16, and 18) were obtained by a slow evaporation of aqueous (or methanol) solution of CuCl2 and corresponding (CnH2n+1NH3)Cl under the mixing of stoichiometric ratio. The phase transition behaviors of these compounds were evaluated by a DSC in the temperature range from 150 to 450 K. The temperature-dependent X-ray crystal structural analyses of (C4H9NH3)2CuCl4 were examined for each phase. DSC measurements of (CnH2n+1NH3)2CuCl4 (n = 4~10, 12, 14, 16, and 18) showed a rather complicated phase transition behavior depending on the structural parameter n. For instance, at least, six kinds of crystal phases (a, b, g, d, e, and f) were identified in (C4H9NH3)2CuCl4 by increasing in the temperature from 150 K. The stepwise phase transition temperature (transition enthalpy) was observed at 181 K (a-b; DH = 0.179 kJmol-1), 206 K (b-g; 0.737 kJmol-1), 211 K (g-d; 0.358 kJmol-1), 222 K (d-e; 1.724 kJmol-1), and 343 K (e-f; 0.086 kJmol-1), respectively. From the temperaturedependent X-ray crystal structural analyses of (C4H9NH3)2CuCl4, the crystal systems of a-phase (T = 153 K), b-phase (T = 198 K), d-phase (T = 208 K), and e-phase (T = 297 K) were a centric P21/n, P21/c, acentric P21, and P21/m, respectively. In the low temperature a-phase, the two-kinds of conformations for C4H9NH3+ groups were observed between the two-dimensional perovskite layers. On the contrary, only one C4H9NH3+ conformation with orientational disorder was observed in the high temperature e-phase. The temperature-dependent dielectric constants (e1) of (C4H9NH3)2CuCl4 showed the stepwise anomaly corresponding to the phase transition temperatures in DSC measurements. The magnetic properties of (CnH2n+1NH3)2CuCl4 with n = 4, 7, 12, and 18 also indicated the ferromagnetic transition at 7.4, 7.9, 8.5, and 8.5 K, respectively. The magnetic ordering was not affected by the length of alkyl-chains. [1] B. Kundys et al., Phys. Rev. B 81,224434 (2010).

Keywords:Organic-Inorganic Hybrid, Structural Phase Transition, Perovskite

MS.A4.P.206 Multifunctionality and Symmetry in Oxalate Networks C. Traina,b, E. Pardo,c C. Maxima, M. Verdaguerc, S.I. Ohkoshid , G.L.J.A. Rikkena and B. Dkhil,e aLaboratoire National des Champs Magnétiques Intenses, CNRS, UPR 3228, Grenoble. bUniversité Joseph Fourier, Grenoble. cInstitut Parisien de Chimie Moléculaire, UMR CNRS 7201, UPMC Univ Paris 06, Paris. dDepartment of Chemistry, School of Science, The University of Tokyo, Tokyo, Japan. eLaboratoire Structures, Propriétés et Modélisation des Solides, UMR CNRS 8580 Ecole Centrale Paris, Paris, 92295 Châtenay-Malabry cedex, France. E-mail: [email protected], [email protected] Molecular multifunctional materials gather in the same object several useful properties. The most appealing among them are the ones where two properties not only coexist but interact to give rise to a third,

second-order, property. Magnetism and chirality [1] lead recently to magneto-chiral dichroism (MChD) [2a] or magnetisation-induced second harmonic generation (MSHG) [2b]. In thoroughly sought-for multiferroics, magnetic and ferroelectric orders should be combined to give the magnetoelectric effect [3]. In any case, the overall symmetry of the chemical system is of utmost importance according to Curie’s principle since the symmetry of the properties must be present in the system [4]. To tackle the problem, we chose tris-oxalatochromate(III), a tris(chelated) precursor exhibiting propeller-like chirality, able to build anionic bimetallic oxalate networks, flexible enough to wrap a wide variety of well-chosen cations C+ [1] and provide systems of different dimensionalities D (0D to 3D). We report our endeavours to get 2D and 3D chiral magnets C[M1M2(ox)3], noted C[M1M2]. With resolved chiral template cations, an enantioselective templated [MnCr]- bimetallic anionic layer is induced [2]. The resulting ferromagnet (TC = 7 K) exhibits strong MChD and MSHG effects below TC [2]. With polar cations known for exhibiting ferroelectric properties, we succeed obtaining a similar assembly of honeycomb (6,3) layers and the first oxalate-based multiferroic material [5] (Figure, M, magnetization, P, polarization). With proton-rich cations, we obtain a 3D chiral magnet presenting high protonic conduction [6]. The flexibility of the system produces other appealing but unexpected 0D and 1D structures, also reported, to feed the endless discussion about serendipitic and rational approaches [7].

[1] C. Train et al., Chem. Soc. Rev., 2011, 40, 3297-3312. [2] (a) C. Train et al., Nat. Mater., 2008, 7, 729; (b) C. Train et al., J. Am. Chem. Soc. 2009, 131, 16838-16843. [3] W. Eerenstein, N. D. Mathur, J. F. Scott, Nature 2006, 442, 759; S. W. Cheong, M. Mostovoy, Nat. Mater. 2007, 6, 13; R. Ramesh, N. A. Spaldin, Nat. Mater. 2007, 6, 21. [4] P. S. Halasyamani, K.R. Poeppelmeier, Chem. Mater. 1998, 10, 2753. [5] E. Pardo et al., Angew. Chem. Int. Ed., submitted. [6] E. Pardo et al., J. Am. Chem. Soc. 2011, 133, 15328–15331. [7] E. Pardo et al., Dalton Trans., 2010, 39, 4951–4958; unpublished.

Keywords: Multifunctional materials, magnetism, oxalate ligand Tu peux peut-être supprimer la dernière page dans les références sauf si c’est recommandé.

MS.A4.P.207 Photochemical Properties of HEteroleptic Dinuclear Bis(Dipyrrinato)Zinc(II) Complexes Mizuho Tsuchiyaa, Shinpei Kusakaa, Ryota, Sakamotoa, and Hiroshi, Nishiharaa, a Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo (Japan). E-mail: [email protected] In the system of natural photosynthesis, there are structures that specialize in collecting photo energy called light-harvesting systems. The antenna pigment absorbs light and the resulting exciton is efficiently conveyed through the linker pigments by resonance energy transfer processes. The photo excitation energy is finally transferred to

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Poster Sessions the reaction center to induce a charge separation, followed by chemical reactions. Light-harvesting complexes surround the reaction center, so that they can collect solar energy efficiently. Dipyrrins, which are also called dipyrromethenes, are a group of bidentate ligands containing two pyrrole rings interconnected by a methine bridge at their a-positions. They are well known for their intense molar extinction coefficients in the visible region and high chemical and photochemical stability. Some of dipyrrin complexes are known to be fluorescent, such as BODIPYs and bis(dipyrrinato)zinc(II) complexes. BODIPYs are dipyrrin complexes of disubstituted boron, and they are often used as fluorescent dyes. Bis(dipyrrinato)zinc(II) complexes are zinc complexes of dipyrrins, some of which are known to be the most fluorescent among dipyrrinatometal complexes[1,2]. Unlike BODIPYs, they can be designed as oligomer wires. In this research, inspired by natural photosynthetic systems, heteroleptic dinuclear heteroleptic bis(dipyrrinato)zinc(II) complexes were newly synthesized to function as energy transfer cassettes using dipyrrins as pigments. The dinuclear bis(dipyrrinato)zinc(II) complexes were composed of linker ligands and terminal ligands, which were designed to have excitation energies different from each other and they were aligned based on their excitation energies so that “flow of energy” can be attained. The synthesis of the heteroleptic dinuclear bis(dipyrrinato) zinc(II) complexes were carried out by reacting solutions of dipyrrin ligands in chloroform and a solution of bis(acetylacetonato)zinc(II) in methanol alternately at room temperature. This method enables the stepwise and efficient synthesis of the complexes under mild conditions. Their performance as energy transfer cassettes were evaluated by obtaining their photochemical properties, such as absorption and fluorescence spectra and fluorescence quantum yields.

spectra were observed when o- catechol or other 1,2-diol was added into the solution of complex 1. Therefore, the reaction of the boronic acid group in the complex 1 can be monitored by the luminescence. The tuning of excited state properties by changing the N^N^N ligand in complex 1 will be also presented.

[1] I. V. Sazanovich, C. Kirmaier, E. Hindin, L. Yu, D. F. Bocian, J. S. Lindsey, D. Holten, J. Am. Chem. Soc. 2004, 126, 2664. [2] S. Kusaka, R. Sakamoto, Y. Kitagawa, M. Okumura, H. Nishihara, Chem. Asian J. 2012, in press.

Keywords: pigments, energy transfer, fluorescence

MS.A4.P.208 Synthesis and Luminescent Properties of Novel Cyclometalated Iridium(lll) Complexes Bearing Boronic Acid Group Toward Chemosensors Izumi Tsunoda, Masa-aki Haga, Department of Applied Chemistry, Chuo University, Bunkyo-ku, Tokyo, (Japan). E-mail: [email protected] Luminescent cyclometalated iridium complexes such as Ir(ppy)3 (ppy- = 2-phenylpyridine anion)[1] have been widely studied for applications to organic EL devices and sensors during the last decades. The cyclometalated Ir complexes exhibit wavelength tunable emission with high quantum yields and long emission lifetimes.[2] So, we intended to synthesize a highly phosphorescent Ir complexes bearing a boronic acid group toward chemosensors, since the reactions of boronic acid with bidentane ligands such as 1, 2-diol or sugars have been well known. Therefore, we synthesized a novel mixed-ligand Ir complex 1, [Ir(N^C^N)(N^N^N)]2+, where the ligands N^C^N and N^N^N stand for [(2,6-bis(N-methyl-benzimidazol-2-yl)-phenyl)benzeneboronic acid and 2.6-bis(N-methyl-benzimidazol-2-yl)pyridine(Fig. 1). The UV-vis absorption spectrum of complex 1 in CH3CN showed a typical p-p* ligandcentered (LC) transition at 301 nm and a MLCT transition around 400 nm. The phosphorescence spectrum of complex 1 in CH3CN showed a broad emission band at 597 nm. Upon the increase of solution pH, the phosphorescence intensity was gradually decreased. From the resulting luminescent titration curve, the pKa value of 1 was determined as 10.11 (Fig. 2). Similar changes on phosphorescence

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Fig.2. Luminescent pH-titration curve obtained by pH-dependent phosphorescence spectra of complex 1 [1] K. A. King, P. J. Spellane, R. J. Watts, J. Am. Chem. Soc , 1985, 107, 1431. [2] S. Obara, M. Itabashi, M. Haga, et al., Inorg. Chem., 2006, 45, 8907.

Keywords: Cyclometalated chemosensor

Ir

complex,

phosphorescence,

MS.A4.P.209 Light-induced Selective Dissociation of Pyrazine-bridged Diruthenium Complexes Motowo Yamaguchi, Sara Tsuyuki, and Kiyoshi Sato, Department of Applied Chemistry, Tokyo Metropolitan University, Minami-osawa, Hachioji, Tokyo Japan. E-mail: [email protected] Dinuclear ruthenium complexes have drawn much attention in the development of photochemical molecular devices as the building blocks [1]. We have reported the syntheses of the symmetrical pyrazine-bridged diruthenium complexes with a terpyridine and a bipyridine and their selective dissociation of the bridging ligand [2]. We have also reported that the switching of light-induced ligand exchange could be realized in the ruthenium complexes with a terpyridine ligand by introducing the redox-responsive quinone/ hydroquinone moiety. The quantum yield of ligand-exchange reaction for the 1,4-benzoquinone-functionalized complex was significantly smaller by a factor of about 40 compared to the complex with a

hydroquinone moiety [3]. To combine two previous studies, we have prepared the pyrazinebridged symmetrical diruthenium complexes having a terpyridine ligand with a redox-responsive benzoquinone moiety, and their visiblelight induced ligand exchange has been examined. Photoreactions of diruthenium complexes were examined in several solvents under irradiation (l > 300 nm). In acetone, the spectrum of 2 changed with an isosbestic point at about 375 nm and the absorption at 466 nm decreased. The reaction proceeded in two steps as shown in equation 1. At first, one of the coordination bonds of the bridging pyrazine was selectively cleaved to give the mononuclear pyrazine complex, then the pyrazine dissociated by further irradiation. The quasi-first order rate constant of the first step of the reaction for 2 having a quinone group was slower that of 3 with a dimethoxyphenyl group by a factor of six as shown in Fig. 1. It is assumed that the ligand photodissociation was suppressed by photo-induced electron transfer to the benzoquinone moiety in excited state.

crown-6) (DCH = dicyclohexano) between ferromagnetic layers of [MnIICrIII(oxalate)3]-. Figure 1 shows the crystal structure of (m-fluoroanilinium+) (DCH[18]crown-6)[MnIICrIII(oxalate)3]- (1) at 93 K. Crystal system and space group of 1 are orthorombic and P212121, respectively. In the crystal, two crystallographically independent supramolecular anions and [MnIICrIII(oxalate)3]- units were observed. The [MnIICrIII(oxalate)3]layers formed two dimensional honeycomb structure. Between the anionic layers, supramolecular cations of (m-fluoroanilinium+) (DCH[18]crown-6) were located, which formed through hydrogen bonding between the nitrogen atom of m-fluoroanilinium+ and the oxygen atoms of DCH[18]crown-6. The salt 1 exhibited a ferromagnetic behavior with the ferromagnetic transition temperature at 5.5 K by the AC susceptibility measurement. Details of dielectric properties in term of molecular rotation will be discussed.

Scheme 1

Figure 1. The absorption change at ca. 450 nm of the pyrazine-bridged diruthenium complexes [1] V. Balzani, M. Venturi, and A. Credi, Molecular Devices and Machines, WILEY-VCH, Weinheim, 2003, 37. [2] M. Yamaguchi and M. Jyumonji, 37th ICCC, 2006, p263. [3] M. Yamaguchi, T. Masano, K. Sato, submitted for publication.

Keywords: dinuclear ruthenium complex, photochemical ligand dissociation, photo-induced electron transfer

MS.A4.P.210 Structure and Dielectric Properties of a Supramolecular Rotator in (m-fluoroanilinium+)(dicyclohexano[18]crown-6) II III [Mn Cr (oxalate)3]Masashi Yoshitake,a Kazuya Kubo,a,b Toru Endo,a Shin-Ichiro Noro,a,b Tomoyuki Akutagawa,c Takayoshi Nakamura,a,b aGraduate School of Environmental Science, Hokkaido Univ. (Japan). bResearch Institute for Electronic Science, Hokkaido Univ. (Japan). cInstitute of Multidisciplinary Research for Advanced Materials Tohoku Univ. (Japan). E-mail: [email protected] We reported (m-fluoroanilinium+)(dibenzo[18]crown-6) [Ni(dmit)2-] salt showing ferroelectric behavior arising from flip-flop motion of the aryl moiety in the supramolecular structure[1]. As a next step, in order to develop multiferroic materials, we introduced a supramolecular cation stracture of (m-fluoroanilinium+)(DCH[18]

Figure 1 Crystal structure of 1. [1] T. Akutagawa et al., Nature Materials 2009, 8, 342.

Keywords: Multiferroic Materials, Supramolecular Cation, Molecular Rotation

MS.B1.P.212 Multiredox High-nuclearity Metallopolygons Masaaki Abe, Atsushi Inatomi, Yoshio Hisaeda, Department of Chemistry and Biochemistry, Kyushu University, Nishi-ku, Fukuoka, 819-0395 (Japan). E-mail: [email protected] Metallosupramolecular chemistry has gathered a widespread interest recently and yielded a versatile range of 2D and 3D discrete architectures. Not only their inherent geometrical beauty but also their diverse functions such as molecular recognition and catalysis have been a major focus of research. Cyclic supramolecules constructed from redox-active transition-metal components are recently emerged, new electronically-active species which may be applied to molecular quantum cellular automata for nanoscopic information transfer devices. Herein we report the synthesis, structures, and electron transfer (ET) phenomena of an unprecedented series of redox-active, polygonal nanostructures which was derived from oxo-triruthenium clusters and organic diazine spacers.

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Poster Sessions When pyrazine was used as a spacer, the molecular square, pentagon, and hexagon of the Ru3 component were isolated. Only a hexagonal cluster was obtained when 1,4-diazabicyclo[2.2.2]octane (dabco) was used, and the molecular structure was determined by X-ray diffraction (Fig. 1). The hexagon forms close-packed hexagonal sheet arrangement and 1D columnar stacking. Cyclic voltammetry revealed that pyrazine-bridged polygonal clusters exhibit reversible multiredox behavior ascribed to elecctronic delocalization over the molecule but the dabco hexagon, showing a reversible two-step feature in the reduction process, forms a trianionic intermediate as a mixed-valent state which can be electrostatically stabilized. Controlled-potential IR spectroscopy revealed that the pyrazine cluster shows nearly averaged line shape for n(CO) absorption band in the mixed-valent state, indicating that intramolecular electron transfer occurs in the IR timescale. In contrast, much slower ET kinetics was suggested for the dabco cluster. Structural determination of pz-bridged “Ru3 square” and porphyrin-bridged box-shaped assemblies will be also presented.

is more suitable to host large anionic guests such as perrhenate, perchlorate and iodide, despite their low density charge. On the contrary, nitrate, bromide and chloride fit better the smaller cavity of receptor. The higher affinity of 2H66+ towards chloride with respect to perrhenate was also demonstrated by the crystal structure of the adduct [2H6(Cl)](ReO4)5·6H2O. The outstandingly favourable affinity of receptor 1H66+ towards ReO4- opens new perspectives for the development of selective materials for both perrhenate recovery and postelution concentration of the anion solutions, obtained from the 188 W/188Re generator. Due to the similar features of perrhenate and pertechnetate, the obtained results are also promising for the application of receptor 1H66+ to 99mTcO4- recognition.

[1] V.Amendola, G. Alberti, G. Bergamaschi, R. Biesuz, M. Boiocchi, S. Ferrito, F.-P. Schmidtchen, submitted for publication;D. Farrell, K. Gloe, G. Goretzki, V. McKee, J. Nelson, M. Nieuwenhuyzen, I. Pál, H. Stephan, R. M. Town, K. Wichmann, Dalton Trans., 2003, 1961–1968;

Fig. 1. Molecular structure of the dabco-bridged Ru3 hexagon.

Keywords: molecular polygons, electron transfer, mixed-valent states

MS.B1.P.213 Cavity Effect on Anion Recognition by Polyammonium Cages Valeria Amendola,a Giancarla Alberti,a Greta Bergamaschi,a Raffaela Biesuz, a Stefania Ferrito,a Franz-Peter Schmidtchen,b aDepartment of Chemistry, University of Pavia, Pavia (Italy). bDepartment of Chemistry, Technical University of Munich, Garching (Germany). E-mail: [email protected] The affinity of azacryptands 1-5 towards perrhenate has been investigated by potentiometric, 1H-NMR and ITC studies in aqueous solution.[1] Only for receptors 1 and 2, in the hexaprotonated form, the association constants could be determined. The experimental results pointed out the outstanding affinity of receptor 1H66+ for perrhenate, attributable to the geometric complementarity between the anion and the receptor’s cavity. Single crystals of the inclusion complex, [1H6(ReO4)](CF3SO3)5·8(H2O), could be also obtained. The X-ray diffraction studies indicate that the perrhenate anion is included into the receptor’s cavity, and interacts with the ammonium groups by means of both direct and water mediated H-bonding interactions. Receptors 1-2 were also investigated in the presence of different anions (i.e. chloride, bromide, iodide, perchlorate and nitrate). The affinity trend demonstrates that receptor 1H66+’s cavity

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Keywords: anion receptor, H-bonded adduct, cryptand

MS.B1.P.214 Real time monitoring of DNA Structural Hybridization Rashid Amin1,2, Atul Kulkarni3, Taesung Kim2,3 and Sung Ha Park,2,4 1 Interdisciplinary Research Center in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology, Lahore, Pakistan, 2 Sungkyunkwan Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Korea, 3School of Mechanical Engineering, Sungkyunkwan University, Korea, 4BK21 Physics Division and Department of Physics, Sungkyunkwan University, Korea, Frontier Research Lab. Samsung Advanced Institute of Technology, Korea. E-mail: [email protected] We report here the electrical detection of DNA Structural Hybridization. In structural DNA nanotechnology, self-assembly of DNA oligonucleotides can create structures of great complexity in bottom up nanofabrication. Geometrical difference at the sticky ends is an effective method to assemble different DNA nanostructures. In our paper have used Double-crossover (DX) lattice structure; consist of two side-by-side double-stranded helices linked at two crossover junctions. The DX lattice structure consists of eight oligonucleotides; two tiles. A and B, each having four DNA strands. We have taken systematic I/V measurement of the fabrication of each tile and then assembly of DX lattice structure. The DNA tiles being insulator at room temperature give us an increase in resistance as the tiles hybridize for structure fabrication. This real time monitoring of DNA structure hybridization can be very useful for the future DNA nanotechnology and its potential applications. Keywords: DNA, DNA Nanotechnology, Hybridization

Poster Sessions MS.B1.P.215

The search for new methods of cancer diagnosis is leading to the development of multimodal imaging agents that may be detected by techniques such as Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET). A new bimodal imaging agent has been prepared which can be used for dual mode detection of cancer by both MRI and PET imaging. The imaging agent consists of an azamacrocyclic ligand, 1,4-bis (2-pyridilmethyl)-1,4,7triazacyclononane (DMP-TACN), linked to iron oxide nanoparticles through polyethylene glycol (PEG) chains (Mn ~ 600) that are attached to the nanoparticle surface by silanization. The azamacrocyclic ligands serve as complexing agents for radioactive copper (64Cu) for PET imaging, while the iron oxide nanoparticles work both as a carrier and an imaging agent for MRI. The iron oxide nanoparticles have been synthesized by thermal decomposition from iron oleate. The functionalized nanoparticles have sizes ranging between 7–10 nm, as determined by TEM, whilst Nanoparticle Tracking Analysis (NTA) experiments suggest an average hydrodynamic diameter of 50 nm. 64 Cu labeling experiments revealed that the nanoparticles loaded with DMP-TACN have a labeling yield of around 10%. MRI experiments in rats showed the nanoparticles accumulate in the liver 15 min after intravenous administration. 64Cu labeling and breast tumor cell labeling studies are currently being performed using the new nanoparticles. Keywords: iron oxide, azamacrocycle, PET/MRI cancer imaging

MS.B1.P.216 Metal Nanostructures onto a- Cyclodextrin Obtained by Magnetron Sputter Deposition Lorena Barrientos, Ma. Fernanda Fuentes, Daniela Rivas, Juan Pastrian, Carlos Orellana. Departamento de Química, Facultad de Ciencias Básicas, Universidad Metropolitana de Ciencias de la Educación, Santiago (Chile). E-mail: [email protected] The size- and shape-dependent physical properties of inorganic nanoparticles provide tunable materials with broad potential applications[1], such as biological and chemical sensing, diagnostic, and the fabrication of structurally complex nanoparticles further enhances their functionality.[2,3] Their interesting properties are attributed to localized surface plasmon resonances resulting in strong optical extinction at visible wavelengths. In this sense, here we report the chemical design, synthesis, characterization and optical properties of silver, copper and gold nanostructures with different size and shape, such as star-shaped gold nanoparticles, nanrods, and silver and copper nanoparticles onto a-cyclodextrin macrolecules by Magnetron Sputter Deposition. The a-cyclodextrin macromolecules were used as templates to induce of metal nanoparticles growth and agglomeration process of them to generate different nanostructures. The figure 1 shows the transmission electron micrographs of metal nanostructures that were achieved. Through this microscopy have been determinated the nanometric size and the morphology of these systems. On the other hand, the optical properties are in concordance with the surface plasmon resonance of metal nanostructures.

P.MS.B1

Multimodal Mri-Pet Iron Oxide Nanoparticles as Imaging Agents For Cancer José A. Barreto1, Bim Graham2, Holger Stephan3, Leone Spiccia,1 1 School of Chemistry, Monash University, Clayton, VIC, 3800, Australia.2Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia.3 Institute of Radiopharmacy, Forschungszentrum Dresden-Rossendorf, Dresden, 01328, Germany. Email: [email protected]

[1] L.Collen, H. Liao, and J. Hafner, Nano Lett. 2006, 6 (4), 683-688. [2] R.Elghanian et al. Science 1997, 277, 1078-1081. [3] A. Haes, et al. Nano Lett. 2004, 4 (6), 1029-1034. Finally, we want to thanks FONDECYT, grant No. 11110138, for the financial support.

Keywords:nanostructures, cyclodextrin, magnetron sputtering

MS.B1.P.217 Nanosheets of a Multifunctional Two Dimensional Coordination Polymer Salome Delgado,a Almudena Gallego,a Cristina Hermosa,a Oscar Castillo,d Isadora Berlanga,a Carlos Gómez,e Eva Mateo,f José I. Martínez-Ruiz,b Fernando Flores,b Julio Gómez-Herrero,c and Félix Zamora,a aDepartamento de Química Inorgánica, bDepartamento de Física Teórica de la Materia Condensada, cDepartamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Spain .dDepartamento de Química Inorgánica, Universidad del País Vasco, Bilbao, Spain. eInstituto de Ciencia Molecular, Universidad de Valencia, Valencia, Spain, fCentro de Astrobiología (CSIC-INTA), Madrid, Spain. e-mail:[email protected] Research on coordination polymers (CPs), including metal-organic frameworks (MOFs), is getting into the nanoscale. Thus, recent reviews have shown the potential of these materials in different fields. [1-3] Therefore, the development of simple procedures leading to structurally well-defined molecular layers would bring novel materials with unique technological applications. Herein we present the synthesis and structure of a multifunctional laminar 2D-CP, [Cu(μ-pym2S2)(μ-Cl)]n·MeOH (1) which crystal structure shows cavities occupied by the solvent molecules. Solvent exchange from crystals of 1 with H2O or ethanol produces crystalto-crystal transformations leading to [Cu(μ-pym2S2)(μ-Cl)]n·H2O (2) and [Cu(μ-pym2S2)(μ-Cl)]n·½EtOH (3) respectively. Heating crystals of 1-3 leads to formation of cluster [CuI4(μ3-Cl)4(pym2S2)4] 4. DFT calculations have been used for the theoretical analysis of the different structures involved in this study. The DC electrical conductivity and luminescent properties of all compounds has been studied.

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Poster Sessions By immersion of compound 1 to a great excess of water, layer-tolayer separation is observed. These layers can be isolated on surfaces and characterized by AFM and XPS. These experiments demonstrates that water induce exfoliation, without the use of mechanical forces, preserving the chemical composition and spectroscopic features of laminar crystals of compound 1. [1] (a) A. M Spokoyny, D. Kim, A. Sumrein, C. A. Mirkin, Chem. Soc. Rev. 38, 1218, 2009. (b) A. Carne, C. Carbonell, I. Imaz, D. Maspoch, Chem. Soc. Rev. 40, 291, 2011. [2] R. Mas-Balleste, J. Gomez-Herrero, F. Zamora, Chem. Soc. Rev. 39, 4220, 2010. [3] L. Welte, A. Calzolari, R. di Felice, F. Zamora, J. Gómez-Herrero, Nature Nanotech 5, 110, 2010.

Keywords: 2D coordination polymers, exfoliation, nanosheets

MS.B1.P.218 Perdeuterated Lanthanoid Cryptates: Extraordinarily Bright Near-IR Luminophores Christine Doffek,a Nicola Alzakhem,a Mariusz Molon,b Michael Seitza a Inorganic Chemistry I and bInorganic Chemistry II, Department of Chemistry and Biochemistry, Ruhr-University Bochum (Germany). E-mail: [email protected] Complexes that coordinate lanthanoid ions have received considerable attention over the past decades. Ln(III) ions exhibit unique electronic and photophysical properties, which make them highly promising candidates for a wide range of applications [1,2]. Upon irradiation, lanthanoids emit element specific luminescence, which is characterized by long luminescence lifetimes and high quantum yields. Nevertheless, lanthanoid luminescence is prone to non-radiative deactivation processes (quenching), which decrease the luminescence intensity dramatically. Quenching is mainly caused by energy-transfer from the lanthanoid’s excited states onto high energy oscillators near the metal center (O-H, N-H, and C-H). This problem is especially severe with lanthanoid complexes in solution, where these motifs are inevitably present. Synthesis of lanthanoid complexes has to meet several requirements. The ligand has to act as an “antenna”, which is able to absorb light and subsequently transfer it to the lanthanoid ion. Moreover, the ligand’s structure has to be stable and rigid to ensure an efficient shielding of the metal ion from the solvent molecules. In addition to this, the ligand has to be devoid of high energy oscillators to minimize the quenching effect. While this is easy to manage in case of N-H and O-H, the ligand mostly consists of an organic molecule where the C-H motif is ubiquitous. In the past, the method of deuteration has been developed in order to minimize the energy transfer probability [3,4]. This method was efficiently adapted to the ligand architecture 1 [5], a derivative of the famous Lehn cryptate [6]. This ligand turned out to be an efficient sensitizer for the near-IR emitting lanthanoids ytterbium, neodymium, erbium and even praseodymium. Perdeuteration of the ligand and the rigidification of the ligand’s backbone due to the incorporation of the N,N’-dioxide moiety, lead to an outstanding minimization of nonradiative deactivation processes. Exceptionally long luminescence lifetimes were obtained for each lanthanoid in deuterated acetonitrile. For the ytterbium cryptate, the longest lifetimes was measured in CD3OD (τobs = 91 µs), which is among the highest values reported so far for molecular complexes in solution. X-ray analysis and determination of the luminescence lifetimes revealed the complete absence of methanol molecules in the first coordination sphere. Furthermore, the cryptates exhibit remarkably resistance towards decomplexation, even under challenging HPLC conditions. The combination of high luminescence efficiency and remarkably stability makes 1 quite unique among near-IR luminophores.

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[1] S. V. Eliseeva, J.-C. G. Bünzli, Chem. Soc. Rev., 2010, 39, 189-277. [2] J.-C. G. Bünzli, S. V. Eliseeva, J. Rare Earth, 2010, 28, 824-842. [3] W. R. Browne, J. G. Vos, Coord. Chem. Rev., 2001, 219-221, 761-787. [4] C. Bischof, J. Wahsner, J. Scholten, S. Trosien, M. Seitz, J. Am. Chem. Soc., 2010, 132, 14334-14335. [5] C. Doffek, N. Alzakhem, M. Molon, M. Seitz, Inorg. Chem., 2012, 51, ASAP. (DOI: dx.doi.org/10.1021/ic202376k). [6] J.-M. Lehn, C. O. Roth, Helv. Chim. Acta, 1991, 74, 572-578.

Keywords: lanthanoids, luminescence, cryptands

MS.B1.P.219 Malonamide Ligands: a Supramolecular Approach for the Extraction of F-Elements Marie-Claire Dul,a Damien Bourgeois,a Jérôme Maynadié,a Daniel Meyer,a aInstitut de Chimie Séparative de Marcoule (ICSM), Laboratoire de Chimie et Physico-chimie des Actinides, UMR 5257, Bât. 426, BP 17171, 30207 Bagnols-sur-Cèze CEDEX, FRANCE. E-mail: [email protected] Malonates and malonamides ligands are well known to coordinate metal ions and especially f-elements ions, due to the hard Lewis character of the oxygen atoms (HSAB theory) and the thermodynamic stabilization induced by the chelate effect of the bidentate [η5-chelation] coordination mode. In addition, to behave as hard ligands due to their carbonyl oxygen atoms, further coordination of these versatile ligands has been exploited to get higher dimensionality compounds exhibiting interesting magnetic and/or luminescent properties for instance. The design of such compounds depends on the coordination bond between the metal ion and the ligands and also on supramolecular interactions (stacking interactions, hydrogen bonding…). The introduction of long alkyl chains and other substituents on the amide groups changes the hydrophobic properties of the malonamide ligands, giving birth to extraction properties. Indeed, in the field of nuclear waste reprocessing, new liquid-liquid solvent extraction processes have been developed in order to coextract some trivalent lanthanides and also minor actinides which are responsible for the long-term radioactivity of nuclear wastes. Besides their good extraction abilities, these malonamide ligands consist of carbon, hydrogen, oxygen, and nitrogen, and hence are completely incinerable. The presence of these hydrophobic groups enhances the solubility of both the free ligand and the metal complexes or ion pairs in the organic phase. These extractants contain lipophilic groups to be soluble in apolar solvents, as well as polar chelating groups. These malonamidebased extractants, with general formula (RR’NCO)2CHR’’, were developed by the French Commissariat à l’énergie atomique et aux énergies alternatives (CEA) and used in the Diamide Extraction (DIAMEX) process for instance.[1] In order to rationalize the liquid-liquid extraction of f-elements by this kind of coordinating bidentate ligand, our original approach consists in modulating the supramolecular organization by introducing various alkyl and other groups. We focus this study on N,N’-tetrasubstituted

malonamides derived from the system DMDBTDMA (R = CH3, R’ = n-C4H9 and R’’ = n-C14H29), as it can exhibit structured organic phases.[2] The supramolecular organization of the malonamides with different lanthanides salts is considered to study the organic phase and better understanding the resulting extraction properties.

[1] C. Cuillerdier, C. Musikas, P. Hoel, L. Nigond, X. Vitart, Sep. Sci. Technol., 1991, 26, 1229. [2] a) L. Berthon, L. Martinet, F. Testard, C. Madic, T. Zemb, Solvent Extr. Ion Exch., 2007, 25, 545 ; b) P. Bauduin, F. Testard, L. Berthon, T. Zemb, Phys. Chem. Chem. Phys., 2007, 9, 3776.

Keywords: Malonamides, f elements, supramolecular organization

MS.B1.P.220

There has been considerable research interest in the design and creation of multinuclear metal complexes that show attractive structures and properties. One-step assembly of multidentate organic ligands assisted by transition metal ions is the most common approach to construct multinuclear complexes. However, this approach often encounters difficulty in the rational construction of heterometallic systems, as well as difficulty in the control and modification of their structures by external factors. An alternative approach that could overcome these difficulties is the use of discrete metal complexes as metalloligands, which have several potential donor groups available for coordination to metal centers. Our interest has been directed to this approach based on thiolato metal complexes with sulfurcontaining aminocarboxylate ligands, such as l-cysteinate (l-cys) and d-penicillaminate (d-pen).[1,2] Recently, we have shown that the reaction of [Au(d-pen)2]3– with NiII gives an S-bridged NiII2AuI2 tetranuclear complex, [Au2{Ni(d-pen-N,S)2}2]2–, in which two square planer [Ni(d-pen-N,S)2]2– units are linked by two linear AuI ions, although other NiIIAuI polynuclear complexes, [Au3{Ni(d-penN,S)3}2]5–, [Au2{Ni(d-pen-N,O,S)2}2]2–, [Au3{Ni(d-Hpen-O,S)3}2]+, were also produced by changing the reaction conditions. Herein we report on structural interconversion between [Au2{Ni(d-penN,S)2}2]2– and [Au3{Ni(d-pen-N,S)3}2]5– by external factors, which is accompanied by drastic changes in color and chirality.

Interrogation of an Iron(II) Dynamic Combinatorial Library by ESI MS Nicholas C. Fletcher,a Hazel I. Phillips,a Aleksey V. Chernikov,a Alison E. Ashcroft,b Andrew J. Wilson,b aSchool of Chemistry and Chemical Engineering, Queen’s University Belfast, Northern Ireland (UK). b Astbury Centre for Structural Molecular Biology and the School of Chemistry, University of Leeds, (UK). E-mail: [email protected] Recently we have been examining ruthenium(II) polypyridyl complexes for the detection of anions.[1] However, the synthesis of these compounds has proved to be challenging given the possibility of geometrical isomerism, along with the wide variety of possible ligands available. One route to overcome this is to investigate a comparable labile system, using dynamic combinatorial chemistry (DCC).[2] This should inform us of the ideal target complex, without synthesizing and subsequently screening a large number of “hopefuls”. We demonstrate here that the composition of a library of 2,2’-bipyridine complexes of iron(II), bearing either an amide or an ester side chain, can be evaluated by ESI-MS. The distribution of components in the library, and the time taken for the system to come to equilibrium, can be readily monitored and both appear to be dependent on the counter anion. Further, for the first time, we show that the distribution of a library of metal complexes can adapt to the most favoured form following the introduction of a different anion. [1] N. A. C. Baker, N. McGaughey, N. C. Fletcher, A. V. Chernikov, P. N. Horton, and M. B Hursthouse, Dalton Trans., 2009, 965-972. [2] P. T. Corbett, J. Leclaire, L. Vial, K. R. West, J. L. Wietor, J. K. M. Sanders and S. Otto, Chem. Rev. 2006, 106, 3652-3711.

Keywords: 2,2’-Bipyridine, Iron(II), Anion-Recognition

MS.B1.P.221 Structural Conversion of d-Penicillaminato NiIIAuI Complexes by External Factors Akeha Fukushima, Nobuto Yoshinari, Asako Igashira-Kamiyama, and Takumi Konno, Department of Chemistry, Graduate School of Science, Osaka University, Osaka (Japan). E-mail: [email protected]. osaka-u.ac.jp

[1] M. Taguchi, A. Igashira-Kamiyama, T. Kajiwara, T. Konno, Angew. Chem. Int. Ed. 2007, 46, 2422-2425. [2] Y. Sameshima, N. Yoshinari, K. Tsuge, A. Igashira-Kamiyama, T. Konno, Angew. Chem. Int. Ed. 2009, 48, 8469-8472.

Keywords: Heterometallic complexes, S-bridged structures, Metalloligands

MS.B1.P.222 Supramolecular Spin-Crossover Complexes Malcolm A. Halcrow, Thomas D. Roberts, Amedeo Santoro, Simon A. Barrett. School of Chemistry, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, UK. E-mail: [email protected] Compounds that undergo a spin-state transition upon cooling or irradiation have potential applications in information storage, sensors or display devices [1]. It is still a challenge to engineer materials that undergo such transitions in a technologically favorable manner, and there is continuing wide interest in the chemistry and physics of these phenomena. For over ten years we have been studying compounds of formula [Fe(bpp)2]2+, where bpp is a tridentate ligand of the 2,6-di(pyrazolyl)pyridine type (either 1-bpp or 3-bpp) [2]. We can derivatise these ligand frameworks at both the pyrazole and pyridine rings, leading to a wide range of iron(II) compounds showing different spin-crossover regimes, but all based around the same metal/ligand core. We have recently demonstrated that [Fe(3-bpp)2]2+, which was first reported nearly 25 years ago [3], is remarkably sensitive to its environment. Its spin-crossover midpoint temperature T½ is shifted to 60-70 K higher temperature in aqueous solution compared to organic solvents [4]. As well as explaining some anomalous properties of that

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Poster Sessions

Poster Sessions complex, this is a much stronger sensitivity to solvents than for any compound reported before. Clearly the iron centre in [Fe(3-bpp)2]2+ is very sensitive to changes in hydrogen bonding to the ligand pyrazolyl N–H groups [4]. More recent data indicate that [Fe(3-bpp)2]2+ is also sensitive to anions in non-aqueous solvents, with halide counterions shifting T½ upwards to a small extent. These data, and other derivatives of [Fe(3-bpp)2]2+ designed to optimise these supramolecular interactions [5], will be described in the presentation.

[1] A. Bousseksou, G. Molnár, L. Salmon, W. Nicolazzi, Chem. Soc. Rev. 2011, 40, 3313-3335. [2] M. A. Halcrow, Coord. Chem. Rev. 2009, 253, 2493-2514 and refs. therein. [3] K. H. Sugiyarto, H. A. Goodwin, Aust. J. Chem. 1988, 41, 1645-1663. [4] S. A. Barrett, C. A. Kilner, M. A. Halcrow, Dalton Trans. 2011, 40, 12021-12024. [5] T. D. Roberts, F. Tuna, T. L. Malkin, C. A. Kilner, M. A. Halcrow, Chem. Sci. 2012, 3, 349-354.

Keywords: spin-crossover, supramolecular, iron

MS.B1.P.223 Highly Selective Al3+ Probe Based on Calix[4]arene Au(I) Isocyanide Scaffold Franky Ka-Wah Hau, Xiaoming He, Wai Han Lam and Vivian WingWah Yam*, Institute of Molecular Functional Materials (Areas of Excellence Scheme, University Grants Committee, Hong Kong) and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P.R. China. E-mail: [email protected]; wwyam@ hku.hk The development of chemosensors for the selective binding of various biological and environmental relevant cations has gained considerable attention in recent years with their great potential applications. The majority of the work in this area relies on signal transduction via photoinduced electron transfer, photoinduced chargetransfer or Förster resonance energy transfer (FRET). Previous works by our group have demonstrated the novel concept of the utilization of the on-off switching of Au···Au interactions for metal ion sensing [1,2]. As an extension of our previous work involving the use of Au···Au interactions for metal ion sensing, a bis-alkynyl calix[4]arene Au(I) isocyanide complex has been synthesized and characterized, and demonstrated to show selective binding towards Al3+ [3]. The unique mode of signal transduction by the switching on of Au···Au interactions to give a visual luminescence change from green to red color has been demonstrated.

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[1] V. W. W. Yam, C. K. Li, C. L. Chan, Angew. Chem., Int. Ed., 1998, 37, 2857– 2859. [2] X. He, W. H. Lam, N. Zhu, V. W. W. Yam, Chem–Eur. J., 2009, 15, 8842–8851. [3] F. K. W. Hau, X. He, W. H. Lam, V. W. W. Yam, Chem. Commun., 2011, 47, 8778-8780.

Keywords: aurophilicity, calixarenes, sensors

MS.B1.P.225 Supramolecular Architectures: Capsules, Catenanes and Coordination Networks James J. Henkelis,a Lindsay P. Hardingb and Michaele J. Hardiea a School of Chemistry, University of Leeds, Leeds (UK). bDepartment of Chemical and Biological Sciences, University of Huddersfield, Huddersfield (UK). E-mail: [email protected] Cyclotriveratrylene (CTV, 1) is a rigid bowl-shaped cavitand with intriguing host-guest capabilities.[1] Appending the upper rim with suitably tailored “arms” provides a unique set of binding sites capable of coordinating the transition, and lanthanide metal series alike. The resultant metallo-supramolecular structures are diverse, including: capsules and cages, such as C3-symmetric cryptophanes and stellated polyhedra;[2] various 1, 2 and 3-dimensional coordination complexes, many with significant internal void space; and topologically non-trivial constructs, such as knots and catenanes.[3] Such species highlight interesting properties and applications, including: gas storage and sequestration, anion recognition and in catalysis, by use as nano-scale micro-reactors.[4] We hereby report the synthesis of novel pyridine and pyridineN-oxide functionalised ligands, which have proven effective in coordinating the transition and lanthanide metals to afford a plethora of supramolecular assemblies. Topologically non-trivial species have been synthesized and elucidated, in the form of a triply interlocked [2]-catenane, [Ag6L13(DMF)n]∙6ClO4, where L1 = tris(3-pyridylmethyl) cyclotriguaiacylene.[5] This is the second structure of its kind – based on metallo-cryptophanes – to date. Here, two M3L2 capsules assemble and interlink simultaneously without the need of a template. Although mechanically interlocked, each M3L2 capsule is chemically independent of the other. 2-D and 3-D polymeric structures were formed from reactions of L2 with cobalt and silver salts respectively, where L2 = tris(isonicotinoylN-oxide)cyclotriguaiacylene. The former crystallizes as a (3,6)-connected coordination polymer with the rarely reported kagome

Poster Sessions coordination behaviour of an analogous digold(I) metalloligand that possesses thiomalic acid, instead of d-pen, will also be reported.

[1] A. Igashira-Kamiyama, T. Konno, Dalton Trans. 2011, 40, 7249-7263. [2] R. Lee, A. Igashira-Kamiyama, H. Motoyoshi, T. Konno, CrystEngComm, 2012, 14, 1936-1938.

Keywords: Supramolecular chemistry, Gold(I) ion, S-bridged structures

MS.B1.P.227

Fig. 1. CTG, 1 and {[Cu5(L3)2Cl10]}∞, 2 [1] M J. Hardie, Chem Soc Rev 2010, 39, 516. [2] T K. Ronson et.al, Angew. Chem. Int. Ed 2007, 46, 9086. [3] T K. Ronson et.al, Nat. Chem. 2009, 1, 212. [4] Y. Inokuma, M. Kawana and M. Fujita, Nat Chem 2011, 3, 349. [5] J J. Henkelis, T K. Ronson, L P. Harding and M J. Hardie, Chem. Commun, 2011.

Keywords: cavitand, capsule, catenane

MS.B1.P.226 Coordination of Diphosphine-Bridged Digold(I) Metalloligands Toward Nickel(II) Kosuke Igawa, Natsuko Matsushita, Nobuto Yoshinari, Asako IgashiraKamiyama, Takumi Konno, Department of Chemistry, Graduate School of Science, Osaka University, Osaka (Japan). E-mail: konno@ chem.sci.osaka-u.ac.jp To date, a number of multinuclear transition metal complexes and coordination polymers have been synthesized by the use of thiolato metal complexes as an S-donating metalloligand.[1] For example, it has been shown that a mononuclear AuI complex with d-penicillamine (d-H2pen), [Au(d-pen)2]3–, reacts with transition metal ions to afford a variety of S-bridged heterometallic multinuclear complexes.[1] In order to expand the range of this chemistry, we recently introduced a digold(I) unit having bis(diphenylphosphino)ethane (dppe) as a linker, in place of the AuI atom in [Au(d-pen)2]3–. The resulting digold(I) complex, [Au2(dppe)(d-pen)2]2–, was found to react readily with CoIII to produce a cationic AuI4CoIII2 hexanuclear complex [Au4Co2(dppe)2(dpen)4]2+, in which two CoIII ions are linked by two [Au2(dppe) (d-pen)2]2– metalloligands.[2] Herein, we report the coordination behaviour of [Au2(dppe)(d-pen)2]2– toward NiII. While an analogous, but neutral hexanuclear structure in [Au4Ni2(dppe)2(d-pen)4] (1) was constructed from the coordination of [Au2(dppe)(d-pen)2]2– to NiII, 1 constructed a supramolecular structure quite different from that found for [Au4Co2(dppe)2(d-pen)4]2+ in the solid state. In addition, 1 was found to exhibit a single-crystal to single-crystal transformation, accompanied by a drastic change in molecular arrangement. The

Long-Distance Hole Transfer in a Hydrogen-Bonded Supramolecular Assembly Atsushi Ikegami, Masaaki Abe, Hisashi Shimakoshi, Yoshio Hisaeda, Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka, (Japan). E-mail: ikegami@ ms.hisaeda.cstm.kyushu-u.ac.jp Electron and hole transfer over a long distance has attracted considerable attention from the viewpoints of both chemistry and biology. For example, mixed valence-state and charge separation are caused by the electron or the hole transfer through a spacer between the remote redox centers or electron donor and acceptor. A great number of compounds involving π-conjugated organic spacers have been synthesized to construct the long-range electron transfer systems. Recently, the noncovalent linkage of electron donor and acceptor systems are reported by using the supramolecular concepts to mimic the natural system more closely. However, there is difficulty in arranging the mediating units at an ideal place without any bonds. To overcome this issue, we fixed the mediating units between the remote redox centers. In this presentation, we report a long-distant hole transfer system within a dimeric structure of trinuclear clusters modified with ferrocenyl carboxylates. Monomeric subunit Ru2MgO(F cCOO)4(AcO)2(tbpy)2(H2O) (1) was prepared in the analogous manner we reported previously [1]. The dimeric structure constructed by the multipoint hydrogen bonds was confirmed by the X-ray crystallography (Figure 1). Eight ferrocenyl groups working as a hole transfer mediator were intervened in the edge of Ru2O cores. This structure retained in a solution, which was confirmed by the diffusion coefficients obtained by the DOSY measurement. The diffusion coefficient was increased after an addition of CD3OD because the dimeric structure dissociated into the monomeric subunit. The electrochemical properties were evaluated by measuring the cyclic voltammograms (CVs) and differential-pulse voltammograms (DPVs). Stepwise oxidations of the Ru2O units were observed, showing the occurrence of hole transfer between the trinuclear clusters. Another dimeric structure without the ferrocenyl units did not show the hole transfer between the trinuclear clusters, that strongly suggests the ferrocenyl units play an important role in this system.

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dual topology, and displays relatively high potential porosity within individual 2-D sheets; the latter as a 3-D (3,6)-connected coordination polymer of pyrite-like topology and features ligand unsupported argentophilic interactions. L3 (tris(2-pyridylmethyl-N-oxide)cyclotriguaiacylene) forms 2D coordination networks with 63 topologies in the complexes {[Cd(L3) (NO3)2]∙2(DMF)∞ and {[Cu5(L3)2Cl10]}∞, the latter displaying large uni-direction channels within the extended crystal lattice, 2. The discrete capsule [Ag2(L3)2(NMP)4]∙2(BF4) exists as a discrete M2L2 dimer and highlights “hand-shake” host-guest interactions, supported by π-π stacking.

Poster Sessions kinetically stable NdIII3·TCAS2 as the major product of the selfassembly. Contrary to the case of YbIII·TCAS, NdIII·TCAS was also detected on HPLC to show high kinetic stability unexpected form the exo-type ligation of TCAS, highlighting the inertness of the S-LnIII bonding for LnIII having larger ionic radii. In any cases, the construction of kinetically stable LnIII complex by formation of multi-LnIII core with an exo-type ligand is a very unique approach as compared to ligand design relying on endo-type ligands having high denticity. The luminescence properties of NdIII3·TCAS2 and YbIII3·TCAS2 complexes as well as the self-assembly behavior of other LnIII species with TCAS will be reported.

Figure 1. Crystal structure of 12. [1] A. Ikegami, M. Abe, A. Inatomi, Y. Hisaeda, Chem. Eur. J. 2010, 16, 4438-4441.

Keywords: Hole Transfer, Metallosupramolecular Assembly, Mixed Valence State [1] N. Iki, et al., Inorg. Chem., 2012, 51, 1648-1656.

MS.B1.P.228 Self-assembly of Thiacalix[4]arene and LnIII to Kinetically Stable Complexes Nobuhiko Iki, Shouichi Hiro-oka, Teppei Tanaka, Hitoshi Hoshino, Graduate School of Environmental Studies, Tohoku University, Sendai (Japan). E-mail: [email protected] Supramolecular complex containing lanthanide(III) (LnIII) has drawn growing attention owing to its sensing and signaling functions such as luminescence and 1H-relaxivity arising from the 4f electrons to lead to novel molecular probes and imaging agents. One of the prerequisites of the LnIII complex is high kinetic stability in vivo, where free ligands and LnIII ions are steadily separated each other. Because of its inherent nature such as the large ionic radius (112-130 pm) and the spherical shape, LnIII tends to form labile complexes with ligands having low denticity (up to 6). To circumvent the inherent lability of the LnIII complex, ligands providing high kinetic stability have been designed on the basis of endo-receptor-shaped ligands (e.g. DTPA and DOTA) to encapsulate the LnIII center inside the molecule with its high number of donating atoms (typically, 8). Recently, we found that thiacalix[4]arene-p-tetrasulfonate (TCAS) formed a 1:1 complex (LnIII·TCAS) with LnIII (= NdIII, YbIII) by simply mixing the components in aqueous solutions for an hour [1]. Notably, TCAS coordinates to LnIII ion with O,S,O-tridentate fashion at the surface of the narrower rim of calixarene ring, not encapsulating in the cone-shaped cavity, thus behaving as an exo- rather than endoreceptor. Very recently, we accidentally found that a part of absorption spectra of NdIII·TCAS and YbIII·TCAS gradually changed during a period of days, suggesting re-assembly of LnIII·TCAS. This prompted us to precisely monitor the self-assembly processes of LnIII (= NdIII, YbIII) and TCAS with using HPLC. As a result, the two LnIII-TCAS systems showed very slow processes of self-assembly to lead to a supramolecular complex LnIII3·TCAS2 having a LnIII3 core sandwiched by two TCAS cones. The fact that YbIII3·TCAS2 was detected on HPLC suggests its high kinetic stability. On the other hand, intermediates such as YbIII·TCAS were not observed, suggesting the lability. Thus, the significant outcome of the self-assembly to YbIII3·TCAS2 was the high kinetic stability to circumvent the lability of YbIII·TCAS. The NdIII system also gave

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Keywords: self-assembly, lanthanide, thiacalixarene

MS.B1.P.229 Synthesis and Redox Behavior of Triruthenium Core-Assembled Loop-like Complexes Atsushi Inatomi, Masaaki Abe, Hisashi Shimakoshi and Yoshio Hisaeda, Institute for Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Moto-oka 744, Nishi-ku, Fukuoka 819-0395, Japan. E-mail: [email protected]. kyushu-u.ac.jp Ligand-bridged assemblies of multinuclear metal complexes have been of considerable interest recently due to their unique properties such as electron transfer reactions in relevance with molecular electronics and computation. Oxo-centered acetate-bridged triruthenium clusters of the type [Ru3(m3-O)(m-CH3CO2)6L3] exhibit enormous advantage as building blocks because of their reversible multi-electron redox activity[1]. We have recently reported the synthesis of linearly linked oligomers including dimers, trimers, and tetramers of the triruthenium cores which were bridged by pyrazine (pz) and 4,4’-bipyridine (bpy) [2]. Herein we report the synthesis, structures, and redox properties of a series of triruthenium core-assembled loop-like complexes containing pz, bpy, 1,3-bis(4-pyridyl)propane (bpp), and 1,4-diazabicyclo[2,2,2] octane (dabco) as bridging ligands. The pz-, bpy-, bpp- and dabco-bridged loops were prepared by reacting [Ru3(m3-O)(m-C2H5CO2)6(CO)(THF)2] with 1 equiv. of pz, bpy, bpp and dabco, respectively. The products were separated by column chromatography and were characterized by spectroscopic methods, electrochemistry, ESI-MS, and X-ray crystallography. 1H NMR spectroscopy revealed highly symmetric structures of the loops. Single crystal X-ray diffraction study revealed that the dabco-bridged hexamer adopts chair-like conformation and the pz-bridged tetramer shows a perfectly planar, square shape. Cyclic voltammetry and differential-pulse voltammetry of the pz-bridged loops show multistep electron transfer for the Ru3(II,II,III)/(II,III,III) process, which indicates that the pz- and bpy-bridged loops show cluster–cluster interactions mediated by p* orbital of the bridging ligand as reported in the dimer of the triruthenium cluster. The redox wave of pz-bridged

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loops is more clearly separated than bpy-bridged loops, indicating p* orbital level is important for the degree of cluster-cluster interactions. The dabco-bridged hexamer shows two-step feature for the corresponding process, which indicates the existence of electrostatic interaction between the Ru3 units. The bpp-bridged loops show twostep electron-transfer in dimer and single step electron-transfer in trimer, tetramer, pentamer, and hexamer for the Ru3(II,II,III)/(II,III,III) process because of the lack of p-conjugation within the bridging ligand and the large electrostatic interaction which only occurs for the dimer with the smallest inner space. [1] A. Inatomi, M. Abe, and Y. Hisaeda, Eur. J. Inorg. Chem. 2009, 4830. [2] M. Abe, A. Inatomi, and Y. Hisaeda, Dalton Trans. 2011, 2289.

Keywords: molecular loop, redox, multinuclear complex

MS.B1.P.230 Coordination Polymers for ClO4- Removal from Water Tatsunari Inoue, Mitsuru Kondo, Department of Chemistry, Shizuoka University, Shizuoka (Japan). E-mail: [email protected] Perchlorate ion (ClO4-) is difficult to remove from water because of its high solubility. Since this anion interferes with the thyroid’s uptake of iodide which is an essential component of growth hormones, ingestion of excess ClO4- would cause serious effects, particularly, on growth of newborns and children.[1] Therefore, developments of materials which can remove ClO4- from water are important subjects. Recently, we have reported that 1,4-bis(imidazol-1-yl-methyl)-2,3,5,6tetramethylbenzene (bitb) afforded M2L4 type molecular capsule including ClO4-.[2] Since this molecular capsule was insoluble in water, ClO4- was conveniently removed from aqueous solutions. That is, additions of CuSO4·5H2O and bitb to aqueous solutions of ClO4-, the anion was removed due to the formation of water-insoluble molecular Cu2(bitb)4(ClO4)2]ClO4 (1). In this work, we have capsule [(ClO4) synthesized two coordination polymers constructed by Cu2+ ions and bitb as the new ClO4- removal materials from water. Treatment of Cu(OH)2 and bitb in EtOH/ammonia aq. yielded {[Cu(bitb)(CO3)]·2H2O}n (2) as purple crystals. The structure was clarified by single crystal X-ray diffraction study. The CO32- ion would be formed by reaction of OH- with CO2. The copper ions are connected by bitb and CO32- to give 2D structure (Figure 1). The other coordination polymer {[Cu2(bitb)3(CO3)2]·3H2O}n (3) was obtained by treatment of 2 with bitb in EtOH. The structural determination by X-ray analysis technique exhibited that 3 has a herringbone type 2D framework (Figure 1). After additions of 2 or 3 to the aqueous solution of ClO4- (1.0 mM), the change of ClO4- concentration depending on time was monitored for the each compound. This study showed that about 1.0 mM of ClO4was reduced to 0.9 mM within 120 min by 2. On the other hand, the concentration was reduced to about 0.2 mM within an hour by addition of 3. This result revealed that 2 and 3 have ClO4- removal ability from water, and the ability is higher for 3. Characterizations of the reaction products revealed that the ClO4- removal was due to the conversions of 2 and 3 to 1.

Figure 1. Structural conversions of the Cu-bitb system.

[1] J. Wolff, Pharmacol. Rev. 1998, 50, 89-105. [2] T. Hirakawa, M. Yamaguchi, N. Ito, M. Miyazawa, N. Nishina, M. Kondo, R. Ikeya, S. Yasue, K. Maeda, F. Uchida, Chem. Lett. 2009, 38, 290-291. Keywords: coordination polymer, perchlorate removal, structural conversion

MS.B1.P.231 Cage Effect of Cyclodextrin Dimers on Photolysis of Alkyl Complexes of a Water-soluble Cobalt Porphyrin Koji Kano, Hiroyuki Kuwano, Hiroaki Kitagishi, Department of Molecular Chemistry and Biochemistry, Doshisha University, Kyotanabe, (Japan). E-mail: [email protected] Methylcobalamin is a vitamin B12, which is one of the rare examples of organometallics in biological system and participates in methionine synthesis in vivo. Under ambient conditions, methylcobalamin is unstable because of photoinduced homolysis of the Co(III)-CH3 bond to yield Co(II) and a methyl radical. The methyl radical easily reacts with O2 affording formaldehyde. In the present study, we prepared a supramolecular methylcobalamin model composed of CH3-CoIIITPPS (TPPS: 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin dianion) and per-O-methylated b-cyclodextrin (TMe-b-CD) and found that a CH3Co(III)TPPS was markedly stabilized against photodecomposition upon complexation with TMe-b-CD. R-CoIIITPPS (R = -CH3, -CH2CH3, -CH(CH3)2) was prepared by the ordinary method [1]. CH3-CoIIITPPS (3 mM) in pH 7.0 phosphate buffer in the absence or the presence of b-cyclodextrin (b-CD, 10 mM) or TMe-b-CD (1 mM) was irradiated by light (310-510 nm) from a Xe lamp (150 W) under ambient conditions and the decomposition rate was followed by UV-Vis spectroscopy. The results are shown in Fig. 1. In the absence of cyclodextrin, CH3-CoIIITPPS rapidly decomposed upon irradiation under aerobic conditions. Photolysis converted CH3CoIIITPPS to CoIIITPPS quantitatively. In the presence of b-CD, the photodecomposition was meaningfully suppressed. The remarkable effect in inhibition of the photodecomposition of CH3-CoIIITPPS was observed in the case of TMe-b-CD. Under N2 atmosphere, no photodecomposition occurred, meaning that disappearance of the CH3-Co(III) complex is caused by the reaction of O2 with the methyl radical formed by photolysis. It has been known that the TPPSH2 free base forms an extremely stable 1:2 TPPSH2-TMe-b-CD inclusion

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Poster Sessions complex in aqueous solution [2]. FeTPPS also forms a similar inclusion complex [3]. A face-to-face dimer of TMe-b-CD prepared by inclusion of a porphyrin can be regarded as a capsule. Our results may be explained as follows. The homolysis of CH3-CoIIITPPS occurs to form a contact radical pair of CH3• and CoIITPPS. The CH3• radical reacts with surrounding O2 to afford HCHO immediately after escape from the cage. The CH3• radical in a TMe-b-CD capsule, however, cannot escape from the cage leading to predominant recombination of CH3• and CoIITPPS. Faster photodecomposition of CH3CH2- and (CH3)2CH-CoIITPPSs complexed with TMe-b-CD may be interpreted in terms of rapid H-transfer from an alkyl radical to CoIITPPS to form a corresponding alkene and H-CoIIITPPS.

Figure 1. Linear Zn(II)2-Tb(III) Trinuclear Complexes Fig. 1. Photodecomposition rates of CH3-CoIIITPPS in the absence (●) and the presence of β-CD (♦) and TMe-β-CD (■). [1] S. Baral, P. Neta, J. Phys. Chem., 1983, 87, 1502-1509. Y. Hisaeda et al., Bull. Chem. Soc. Jpn., 2005, 78, 859-863. [2] K. Kano et al., J. Am. Chem. Soc., 2002, 124, 9937-9944. [3] K. Kano et al., J. Am. Chem. Soc., 2004, 126, 15202-15210.

Keywords: methylcobalamin model, cyclodextrin, photolysis

MS.B1.P.232 Molecular Design of Zn (II)n – Ln(III) Multinuclear Complexes and Their Luminescence Properties Yumiko Kataoka,a Naoko Kusunoki,a Aika Yamashita,a Takayuki Nakanishi,b Yasuchika Hasegawa,b Takashi Kajiwara,a aDepartment of Chemistry, Faculty of Science, Nara Women’s University, Nara, (Japan). bDivision of Materials Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo, Hokkaido, (Japan). E-mail: [email protected] Lanthanide(III) complexes have received recent attension as function devices based on unique chemical, magnetic, and photophysical properties. Among them, luminescent lanthanide complexes offered further multifunctional applications. We synthesized a series of luminescent Zn(II)n-Ln(III) multinuclear complexes with Shiff base ligands including phenol framworks as chromophore moieties. Synthesized Zn(II)2-Tb(III) trinuclear and Zn(II)3-Yb(III) tetranuclear complexes showed luminescence by UV-irradiation at π-conjugated phenol moieties in both solid and CH3CN solution. The Zn(II)2-Tb(III) trinuclear complexes were observed luminescence around 550 nm at Tb(III). The Zn(II)3-Yb(III) tetranuclear complexes showed emission around 960 nm at Yb(III). Their luminescence properties dramatically changed with the addition of specific anion (Cl-, Br-) in CH3CN solution. Particulary, in Zn(II)2Tb(III) trinuclear complexs, the presence of Cl- anion induced 3 fold enhancement luminescence intensity. Luninescence titration curves between Zn(II)2-Tb(III) complexs and Cl- anion suggested that Clanions coordinated two Zn(II) axis, respectively, as a resulting increase of Tb(III) luminescence. Crystal structures of linear Zn(II)2-Tb(III) trinuclear complexes were obtained with Shiff base ligands, showing that each Zn(II) was occupied with two nitrogen and two oxygen atoms on ligand, and a halide anion (Cl-, Br-,. I-) (Figure 1). Two ligands possessing four oxygen donors also bound to a Tb(III), respectively.

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Keywords: Lanthanide complex, Luminescence

MS.B1.P.233 Molecular-Capsule Assemblies of Trinuclear Macrocyclic Metal Complexes Masayuki Koikawa, Masahiro Muto, Kosuke Morinaga, Kou Yoneda, Yasunori Yamada, Tadashi Tokii, Department of Chemistry and Applied Chemistry, Saga University, Saga (Japan). E-mail: koikawa@ cc.saga-u.ac.jp Development of macrocyclic metal ion arrays is of considerable interest in supramolecular chemistry and nano-structural science because these complexes often have characteristic redox, magnetism, molecular-mechanical functions and host-guest chemistry. We prepared modified bridging ligands, H3L5-X, based on 2-(salicylidene­ amino)phenol (H2sap), and obtained trinuclear metal complexes with unique macrocyclic structures [1].

Fig. 1 Chemical structure of H3L5-X Trinuclear manganese(III), vanadium(V), and iron(III) complexes, [Mn(L5-X)(CH3OH)]3 (X = -H; 1, -CH3; 2, and -Br; 3), [VO(L5-H)]3 (4), [Fe(L5-X)(py)]3 (X = -H; 5, -Br; 6) have been prepared and characterized by X-ray crystal structure analysis. The trinuclear structure of 6 is shown in Fig. 2(a). The complex comprises three sets of ligands, iron(III) ions and coordinating pyridines. Three iron(III) centers formed an equilateral triangle arrangement, and the Fe¼Fe distances is in the range 8.183(2) Å. The entire molecular structure of 6 is regarded as a corn-shape geometry with 3-fold rotation axis. Magnetic measurements of these complexes except for 4 indicate that weak anti­ferromagnetic interactions (J ~ –0.1 cm–1) are dominant in the trinuclear manganese(III) or iron(III) core. As for the characteristic structural properties, it is worth noting that these complexes have a cavity. Considering the van der Waals radius, a small molecule with an external diameter of about 3 Å can be held in the cavities. In the crystal packing of 6, two units of complexes are loosely aggregated to form capsular conformation (Fig. 2(b)).



(a)

(b)

[1] M. Muto, N. Hatae, Y. Tamekuni, Y. Yamada, M. Koikawa, and T. Tokii, Eur. J. Inorg. Chem., 2007, 3701-3709.

Keywords: macrocyclic complex, magnetic property, host-guest chemistry

MS.B1.P.234 Syntheses of Coordination Polymers Constructed by Bisimidazoletype Ligands Shiori Koike, Ayako Handa, Mitsuru Kondo, Department of Chemistry, Shizuoka University, Shizuoka (Japan). E-mail: scmkond@ipc. shizuoka.ac.jp Coordination materials constructed by flexible ligands have produced various structures, which were largely affected by many factors such as kinds of metal ions, counter anions, and solvents used for the syntheses. Flexible bisimidazole type ligands expressed by Im-CH2-C6HnMe(4-n)H-CH2-Im (n = 1 or 0, Im = imidazole) have yielded many M2L4 type molecular capsules, while constructions of coordination polymers by using these ligands are still rare.[1] Recently, we have found that 1,4-bis(imidazole-1-yl-methyl)-2,3,5,6-tetramethyl benzene (bitb) afforded M2L4 type molecular capsule including ClO4(Figure 1).[2] In this work, we have studied the effects of NCS- anions on the self-assembled structures for Cu-bitb system, and successfully isolated the two new coordination polymers. Additions of aqueous solutions of CuSO4·5H2O and NaNCS to a THF solution of bitb yielded [Cu(bitb)(NCS)2]THF·H2O (1) as green needle crystals within a few days. On the other hand, when this treatment was carried out in MeOH/MeCN/H2O mixed solvents, [Cu(bitb)2(NCS)](NCS)MeOH·H2O] (2) was obtained as blue needle crystals within a few days. Their structures clarified by the singlecrystal X-ray analyses are shown in Figure 2. For 1, Cu2+ center is bridged by bitb to yield 1-D zigzag chain. The 2+ Cu center is based on the square planar geometry surrounded by the four nitrogen atoms of two bitb and two NCS-. For 2, the Cu2+ centers are bridged by two bitb to form 1-D chain. Each Cu2+ center is based on square pyramidal geometry coordinated by five nitrogen atoms of four bitb and a NCS-. The NCS- occupies the apical position. Since the two bridging bitb binds to the Cu2+ center at the cis-positions, M2L2 type cave is created between the Cu2+ ions. The space is occupied by NCS- which binds to the Cu2+ center. The other NCS- is not associated with Cu2+ ion, but located between the chains. This study demonstrated that anion-dependent formations of coordination networks for Cu-bitb system.

Figure 2. Structures of Compound 2 (a) and 3 (b). [1] H.-K. Liu, J. Hu, T.-W. Wang, X.-L. Yu, J. Liu, B. Kang, J. Chem. Soc., Dalton Trans. 2001, 3534-3540. [2] T. Hirakawa, M. Yamaguchi, N. Ito, M. Miyazawa, N. Nishina, M. Kondo, R. Ikeya, S. Yasue, K. Maeda, F. Uchida, Chem. Lett. 2009, 38, 290-291.

Keywords: bis-imidazole type ligand, coordination polymer, Metal-organic framework

MS.B1.P.235 Unexpected Helical Chirality in Copper(I) Helicate with Chiral Sexi- and Quater-Pyridines Hoi-Lun Kwong,* Kiu-Chor Sham, Guoli Zheng, Yi Pan, Kai-Chung Lau, Shek-Man Yiu, Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR (China). E-mail: [email protected] Helicates, formed by self-assembly between ligand strands and metal ions, are of great current interest[1] because of their relevance to important process in nature and their potential application in fields like DNA binding, molecular machinery, single molecule magnet, luminescent stain, material, catalysis. They are inherently chiral and have both helical chirality (P/M) and chiral metal centers (Δ/Λ).[2] Although there have been interest in the formation of helicate and stereoselective synthesis of helicate is possible, study using chiral helicates in term of understanding the self-assembly process is rare.[3] Cu(I) helicates of chiral sexipyridine L1 and quarterpyridine L2 were synthesized. L1 and L2 bear the same isopinocamphenolbased chiral substituents at the 5,6-position, however, trinuclear Cu(I) complex of chiral sexipyridine L1 is a P-helix while the binuclear copper(I) quaterpyridine L2 is a M-helix.

Figure 1. Obtained compounds depend on kinds of present anions in the reaction solutions of bitb and CuSO4·5H2O.

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Poster Sessions that PHP can mediate the formation of homogeneous Ag(0) NPs assemblies. Interestingly, these assemblies are generated even in the presence of only one equivalent of functionalized peptoid oligomers. Moreover, the addition of PHP to the Ag(0) NPs solution resulted in an immediate color change, which was similar with different R-values. These peptoids/Ag(0) NPs hybrids, as well as the ability of functional biomimetic oligomers to mediate the assembly of metal NPs, hold potential for applications in sensor materials, biology and catalysis.

CD spectrum of [Cu3(L1)2](ClO4)3 and [Cu2(L2)2](ClO4)2 [1] S. E. Howson, P. Scott, Dalton Trans., 2011, 40, 10268. [2] J.-M. Lehn, A. Rigault, J. Siegel, J. Harrowfield, B. Chevrier, D. Moras, Proc. Natl. Acad. Sci. USA, 1987, 48, 2565. [3] C. Piguet, M. Borkovec, J. Hamacek, K. Zeckert, Coor. Chem. Rev., 2005, 249, 705.

Keywords: supramolecular, stereoselectivity, helicates

[1] Zuckermann, R. N.; Kerr J. M.; Kent S. B. W.; Moos W. H. J. Am. Chem. Soc. 1992, 114, 10646. [2] Maayan, G. *; Liu, L-K. Pept. Sci., 2011, 96 (5), 679.

Keywords: keyword-Nanoparticles assembly, keyword-peptoids, keyword-peptidomimetics

MS.B1.P.237

Silver Nanoparticles Assemblies Mediated by Functionalized Biomimetic Oligomers Galia Maayan, Department of Organic and Inorganic Chemistry, Faculty of Chemistry, Technion – Israel Institute of Technology, Haifa (Israel). Email: [email protected]

Azo Dyes Functionalized with Alkoxysilyl Ethers for Chromogenic Detection of the Fluoride Anion Alessandro Agostini,a Michele Milani,b María E. Moragues,a Luis E. Santos-Figueroa,a Ramón Martínez-Máñez,a Maurizio Licchelli,b Juan Sotoa and Félix Sancenón,b aCentro de Reconocimiento Molecular Desarrollo Tecnológico, Universidad Politécnica de Valencia, Valencia, (Spain). bDipartimento di Chimica Generale, Università degli studi di Pavia, Pavia (Italy). E-mail: [email protected]

The organization or self-assembly of nanoparticles (NPs) in multiple dimensions harness their nanoscale attributes and provides unique electrical and optical properties. Ensembles containing both metal NPs and organic or bioorganic molecules are of special interest because they display the properties of both components, leading to a variety of applications in biology, medicine and sensing. We are therefore interested in versatile oligomeric scaffolds that can be easily generated, functionalized and mediate the aggregation of metal NPs, for the construction of organic-inorganic hybrid assemblies, which are compatible with a wide range of temperatures, pH, chemical reagents and more. N-substituted glycine oligomers, or “peptoids”, are artificial mimics of peptides that can be easily synthesized by the solidphase “sub-monomer” method. [1] The efficient synthesis employs primary amines, enabling the incorporation of innumerable functional groups, including capping agents for the binding of NPs, at specified N-positions along their spine. Thus, properties such as chirality, solubility, interaction with metallic surface, hydrophilicity and hydrophobicity, can be tuned in a precise manner via introduction of different side chains at various positions. Moreover, peptoids are stable in a large range of temperature and pH conditions. Herein we present a simple method for the functionalization of silver NPs (Ag(0) NPs) by peptoid oligomers. Based on the established affinity between phenanthroline ligand and Ag(0), we synthesized a peptoid sequence bearing 1,10-phenanthroline at the N-terminus (PHP). The interaction between Ag(0) NPs and PHP was tested at different pH conditions. Clusters with a uniform size were formed at pH=3.5 as shown from UV-vis spectra. Different ratios between PHP and Ag(0) NPs (R = 1, 2 and 4) were used in the synthesis of PHP-Ag(0) clusters at pH = 3.5, enabling the generation of spherical assemblies with similar particles density, as revealed by UV-vis spectroscopy and transition electron microscopy (TEM). [2] These results indicate

Selective recognition of anions is a very active field in supramolecular chemistry. In particular, the development of fluorgenic and chromogenic chemosensors and reagents for anions has been extensively explored in the last years given the important roles played by anionic species in biological processes, in deleterious effects such as environmental pollutants, or as toxic compounds or carcinogenic species.[1] Among inorganic anions, fluoride is routinely used for the prevention of dental caries[2] and for the treatment of osteoporosis. [3] However, acute and chronic fluoride exposure can cause various diseases.[4] For all these reasons the development of chromogenic and fluorogenic chemosensors for the selective detection of fluoride has increased in recent years. Given our interest in the development of chromo-fluorogenic chemosensors for anions [5] and the very few examples described that are able to signal fluoride in the presence of water, we report herein the synthesis, characterization and sensing studies of a new fluoride-selective chemodosimeter based on a pyridine azo dye functionalized with a t-butyldimethylsylil moiety. The fluoride selective chromogenic response arose from the hydrolysis reaction of the silyl ether moiety of probe 1 induced by this anion, which resulted in the formation of the corresponding phenolate anion 2. This hydrolysis reaction results in a red-shift of the main absorption band from 350 to 470 nm which determine a dramatic color change from yellow to orange red (see Figure 1). The linear correlation between the increase of the band at 470 nm and the quantity of fluride anion present let us determine a limit of detection in CH3CN/H2O 9:1 of 0.09 ppm. We also studied the possible use of 1 to design dip-sticks for fluoride detection. For this purpose, chemodosimeter 1 was reacted with (3-iodopropyl)trimethoxysilane in order to obtain the corresponding pyridinium cation which was later covalently anchored to silica TLC surface. The obtained sticks were employed to sense fluoride in CH3CN/H2O 9:1 solution and we were able to detect it at 10-4 mol dm-3 concentration.

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On the other hand, weaker hydrogen bond between water and the ligand NH would be expected to stabilize the diradical electronic configuration to cause one-electron oxidation of [PtII(t-BuLISQ)2].

Figure 1. Chromogenic response of receptor 1 in the presence of fluoride anion [1] (a) J. L. Sessler, P. A. Gale , W.-S. Cho, Anion Receptor Chemistry, Royal Society of Chemistry, Cambridge, 2006. (b) A. Bianchi, K. Bowman, E. GarciaEspaña Supramolecular Chemistry of Anions, Wiley-VCH, New York, 1997. [2] M. Kleerekoper, Endocrinol. Metab. Clin. North. Am., 1998, 27, 441-452. [3] R. H. Dreisbuch, Handbook of Poisoning, Lange Medical Publishers, Los Altos, CA, 1980. [4] WHO (World Health Organization), Geneva, 2002. [5] R. Martínez-Máñez, F. Sancenón, Chem. Rev., 2003, 103, 4419-4476.

Keywords: fluoride, chemodosimeter, dip-stick

MS.B1.P.238 NIR Absorption Change of Diradical Complex Caused by Hydrogen Bond to Solvent Atsuko Masuya, Shotaro Wada, Nobuhiko Iki, Hitoshi Hoshino, Graduate School of Environmental Studies, Tohoku University, Sendai, (Japan). E-mail: [email protected] Near infrared (NIR; 700-1100 nm) light effectively penetrates into biological tissues, and hence in vivo imaging technique based on NIR absorption has received much attention. We have investigated NIR absorbing bis(o-diinimobenzosemiquinonato) platinum(II) to apply it as an NIR probe for recognition of chemical environment of medium such as hydrophobicity and pH.[1] In order to clarify the mechanism of the response to hydrophobicity, herein, we prepared a diradical complex having electron donating tert-butyl group ([PtII(t-BuLISQ)2], Fig.1) and investigated NIR absorption and redox properties of [PtII(tBu ISQ L )2] in DMSO/water mixture. We also discussed interaction between solvent and [PtII(t-BuLISQ)2]. [PtII(t-BuLISQ)2] displayed NIR absorption at 720 nm (e ≈ 7.2 × 104 –1 M ⋅cm–1) in DMSO solution. In DMSO/water mixture (3:7, 2:8 and 1:9 molar ratio), the absorption at 720 nm clearly decreased and the absorption bands at 450 and 840 nm, which are characteristic of oneelectron-oxidized dimer {[PtII(t-BuLISQ)(t-BuLIBQ)]2}, slightly increased (Fig. 2). Hence, the addition of water to DMSO caused one-electron oxidation and dimerization of [PtII(t-BuLISQ)2]. We investigated cyclic voltammetry of [PtII(t-BuLISQ)2] in DMSO and DMSO/water mixture (4:6 molar ratio) (Fig. 3) to reveal the effect of water on the redox behavior. In the DMSO solution, [PtII(t-BuLISQ)2] displayed four oneelectron redox waves. Upon addition of water, negative shift of E21/2 from –0.35 to –0.42 V and positive shift of E31/2 from –1.54 to –1.36 V (vs. Ag/Ag+) were observed. The potential range for [PtII(t-BuLISQ)2] became narrower to cause one-electron oxidation of [PtII(t-BuLISQ)2]. 1 H-NMR spectra of [PtII(t-BuLISQ)2] in various solvents showed that chemical shift of NH proton correlated with proton acceptor ability of the solvent to reveal the formation of NH⋅⋅⋅solvent hydrogen bonding. Strong hydrogen bonding occurs between DMSO and the ligand NH of [PtII(t-BuLISQ)2] accounting for increase of electron density at N which would be expected to stabilize the closed shell electronic configuration.

Fig.2 Absorption spectra of [PtII(tLISQ)2] in DMSO-water mixture. DMSO:water = 10:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9. [PtII(t-BuLISQ)2] = 2.0 × 10–5 M.

Bu

Fig.3 Cyclic voltammogram of [PtII(t-BuLISQ)2] in DMSO-water mixture. DMSO:water = 10:0 (top) and 4:6 (bottom). [PtII(t-BuLISQ)2] = 2.0 × 10–4 M, [[(n-C4H9)4]NClO4] = 0.10 M.

[1] A. Masuya et al, Eur. J. Inorg. Chem., 2010, 3458.

Keywords: diradical complex, near infrared, hydrogen bond

MS.B1.P.239 Displacement Assays With Binuclear Rhodium Complexes For The Fluorogenic Recognition And Signalling Of Carbon Monoxide María E. Moragues,a,c Luis E. Santos-Figueroa,a,c Alessandro Agostini,a,c Félix Sancenón,a,b,c Ramón Martínez-Máñez,a,b,c aCentro de Reconocimiento Molecular y Desarrollo Tecnológico, Mixto Universidad Politécnica de Valencia-Universidad de Valencia, Valencia (Spain). bDepartamento de Química, Universidad Politécnica de Valencia, Valencia (Spain). cCIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN). E-mail: [email protected] Carbon monoxide is known to be a major environmental toxicant that can present a real danger to humans. However, only in the recent years, have scientist begun to explore the possible biological activities of CO. Heme oxygenase-derived CO appears to play a major role as neurotransmitter, regulator of sinusoidal tone, inhibitor of platelet aggregation or suppressor of acute hypertensive responses. Exogenous CO has been found to suppress the inflammatory response associated with injury and/or inflammation (i.e. intestinal), to prevent rejection in organ transplantation and to act as a vasodilator. In this line, it would be interesting to carry out fluorogenic detection of CO in aqueous media. Following our interest on the design of novel chromo-fluorogenic systems,[1] we considered the application of binuclear rhodium compounds as potential probes for the fluorogenic sensing of CO by exploiting the well-known ability of these complexes to coordinate in their labile axial sites.[2] The design of the fluorogenic ensembles involves the use of binuclear rhodium(II) cyclometalated complexes as receptor which form a non-emissive complex with a fluorescent dye (the fluorescence was quenched by the bound metal). Based on the displacement assay approach, upon addition of CO (the target analyte) a displacement occurs; the receptor binds to CO and releases the fluorescent dye to the solution (see Scheme 1). As a consequence of the displacement reaction the fluorescence of the dye is completely restored and the intensity emission is proportional to the CO concentration.

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Scheme 1. Fluorophore displacement by axial CO coordination. [1] M.E. Moragues, R. Martínez-Máñez, F. Sancenón, Chem. Soc Rev., 2011, 40, 2593-2643. [2] M.E. Moragues, J. Esteban, J.V. Ros-Lis, R. MartínezMáñez, M.D. Marcos, M. Martínez, J. Soto, F. Sancenón, J. Am. Chem. Soc., 2011, 133, 15762-15772.

Keywords: displacement assay, carbon monoxide, fluorescence

MS.B1.P.240 Synthesis and Characterization of high quality core/shell nanocrystals Ayorinde Nejo,a Adeola Nejo,a Neerish Revaprasadu,a aDepartment of Chemistry, University of Zululand, Private Bag X1001, KwaDlangezwa 3886, South Africa. E-mail: funaina2004@yahoo. co. uk

work, we synthesized Au3AgAu3 and Au3AgAu3AgAu3 multi-decker ion clusters by alternate accumulation of trinuclear Au(I) complexes and Ag(I) ions within the box-shaped cages. [3 × n] Au(I) homo ion clusters served as templates of Au–Ag hetero ion clusters. When an aqueous solution of [3 × 2] Au(I) ion cluster was treated with AgNO3, the solution color immediately changed from orange to pale yellow. The UV-vis and NMR data proved that only one Ag(I) ion interacted with [3 × 2] Au(I) ion cluster. The structure of the Au–Ag hetero ion cluster was unambiguously determined by X-ray crystallographic analysis (Figure 1b). The Ag(I) ion was bound between the pair of trinuclear Au(I) complexes to form a Au3AgAu3 double-decker ion cluster 1 where Au–Ag interactions work (the Au–Ag distances: 2.731 to 2.922 Å). The alignment of Au– Ag ions in the cluster corresponds to the repeating unit of the Au–Ag infinite crystalline chains. Similarly, a larger Au–Ag hetero ion cluster was prepared in [3 × 3] Au(I) ion cluster. The 1H NMR spectrum revealed that alternate stacking of trinuclear Au(I) complexes and Ag(I) ions occurred to form Au3AgAu3AgAu3 triple-decker ion cluster 2 (Figure 1c). The metal alignment was not equivalent with that of the bulk crystalline chains and, hence, only available in the box-shaped cage. These metal ion uptakes were specific to Ag(I) ions and irreversible as a consequence of the effective Au–Ag interactions.

Recently, there is an increasing attention on multicomponent nanocrystals with a core-shell due to their fascinating and tailored properties for various applications in biological system and optic [1-3]. We report the synthesis and characterization of high quality Type I and Type II core/shell nanocrystals through a simple synthetic route. The properties and structures of the synthesized nanocrystals were characterized by absorption spectroscopy, photoluminescence spectroscopy, X-ray diffraction, transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). TEM images showed that the core/shell nanocrystals are monodisperse with narrow size distributions. The crystalline natures of the nanocrystals were confirmed powder X-ray diffraction. Absorption and photoluminescence spectra demonstrate the tunability of these core/shell systems. This study is expected to contribute to the potential application in the fundamental study as well as fabricating nanodevices. [1] A. Makhal, H. Yan, P. Lemmens, S.K Pal, J. Phys. Chem. C, 2010, 114, 627–632. [2] S. Wang, B.R. Jarrett, S.M. Kauzlarich, A.Y Louie, J. Am. Chem. Soc., 2007, 129, 3848–3856. [3] M. Bruchez Jr., Science 1998, 281, 2013–2016.

Keywords: core/shell, nanocrystals, monodisperse

MS.B1.P.241 Synthesis of Au–Ag Multi-Decker Ion Clusters within SelfAssembled Coordination Cages Takafumi Osuga,a Takashi Murase,a Makoto Fujita,a,b aDepartment of Applied Chemistry, School of Engineering, The University of Tokyo, (Japan), bCREST, Tokyo, (Japan). E-mail: [email protected] Self-assembled coordination cages are suitable box-shaped platforms for discrete stacks of cyclic trinuclear Au(I) complexes to produce [3 × n] (n = 1–3) Au(I) ion clusters (Figure 1a).[1] Imidazolatebridged trinuclear Au(I) complexes tend to interact with Ag(I) ions to form (Au3AgAu3)∞ infinite chains in the crystalline state.[2] In this

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Figure 1. (a) Schematic representation of the synthesis of metal ion clusters. (b) Au3AgAu3 double-decker cluster 1 and the X-ray structure. (c) Au3AgAu3AgAu3 triple-decker cluster 2. [1] T. Osuga, T. Murase, K. Ono, Y. Yamauchi, M. Fujtia, J. Am. Chem. Soc. 2010, 132, 15553–15555. [2] A. Burini, R. Bravi, J. P. Fackler, Jr., R. Galassi, T. A. Grant, M. A. Omary, B. R. Pietroni, R. J. Staples, Inorg. Chem. 2000, 39, 3158–3159.

Keywords: Self-Assembly, Gold, Cluster

MS.B1.P.242 Amphiphilic Anionic Pt(II) Complexes–From Spectroscopic to Morphological Changes Charlotte Po, Anthony Yiu-Yan Tam, Keith Man-Chung Wong, Vivian Wing-Wah Yam,* Institute of Molecular Functional Materials (Areas of Excellence Scheme, University Grants Committee (Hong Kong)) and Department of Chemistry, The University of Hong Kong, Hong Kong (China). E-mail: [email protected], [email protected]

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A new class of amphiphilic anionic platinum(II) bzimpy complexes has been demonstrated to show aggregation in water through Pt∙∙∙Pt and π–π stacking interactions. An interesting aggregation– partial deaggregation–aggregation process and a morphological transformation from vesicles to nanofibers have been demonstrated. These changes can be systematically controlled by the variation of solvent composition and could readily be probed by UV-vis absorption, emission, NMR, transmission electron microscopy and even with our naked eyes.

[1] M. Rancan, A. Dolmella, R. Seraglia, S. Orlandi, S. Quici, L. Armelao, Chem. Commun. 2012, 48, 3115-3117.

Keywords: self-assembly, self-sorting, host-guest

MS.B1.P.244 Study of Furyl-Thiosemicarbazones as New Chemosensors for Anion Recognition [1] C. Po, A. Y. Y. Tam, K. M. C. Wong, V. W. W. Yam, J. Am. Chem. Soc., 2011, 133, 12136–12143.

Keywords: platinum, amphiphilic, supramolecular assembly

MS.B1.P.243 Templating Guests Sort Out Molecular Triangles From a DimerTrimer Constitutional Dynamic Library Marzio Rancan,a Jacopo Tessarolo,a Alessandro Dolmella,b Roberta Seraglia,a Simonetta Orlandi,cd Silvio Quici,cd Lidia Armelao,a Eugenio Tondello,a aISTM-CNR and INSTM, Dept. of Chemical Sciences, University of Padova, Padova, (Italy). bDept. of Pharmaceutical Sciences, University of Padova, Padova, (Italy). cISTM-CNR, Milano, (Italy). dPST-CNR, Milano, (Italy). E-mail: [email protected] Self-assembly and self-sorting processes of dynamic systems are particularly challenging since they represent a key step to obtain functional supramolecular objects. In particular, coordination-driven supramolecular architectures generated from metal centres and well designed polytopic ligands turned out to be an excellent bench test for supramolecular and self-organization concepts. Herein, we present a system that in solution gives a mixture of a copper dimer and an elusive trimer in dynamic equilibrium. This system is a small constitutional dynamic library. The designed introduction of well suited guests allowed us to orchestrate the system response. The guest is able to drive the self-sorting of the mixture toward the trimer by forming a supramolecular triangle. Alternatively, the same guest is able to template triangle self-assembly in a one-pot synthesis. The nature of this multifaceted system has been unravelled by a combination of mass spectrometry (ESI-MSn), absorption spectroscopy and single crystal structural studies[1].

Luis E. Santos-Figueroa,a,b María E. Moragues,a,b Alessandro Agostini,a,b M. Manuela M. Raposo,*c Félix Sancenón,a,b Ramón Martínez-Máñez,*a,b Juan Sotoa. aCentro de Reconocimiento Molecular y Desarrollo Tecnológico (IDM), Centro Mixto Universidad de Valencia-Universidad Politécnica de Valencia (Spain). bCIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN). cCentro de Química, Universidade do Minho, Braga (Portugal). E-mail: [email protected] A family of heterocyclic thiosemicarbazone dyes (3a-f, see Figure 1) containing furyl groups were synthesized in good yields, characterized and their response in acetonitrile in the presence of selected anions studied. [1] Acetonitrile solutions of 3a-f show absorption bands in the 335-396 nm range which are modulated by the electron donor or acceptor strength of the heterocyclic systems appended to the thiosemicarbazone moiety. The anions fluoride, chloride, bromide, iodide, dihydrogen phosphate, hydrogen sulfate, nitrate, acetate and cyanide were used in recognition studies. From these anions, only sensing features were seen for fluoride, cyanide, acetate and dihydrogen phosphate. Two clearly different chromofluorogenic behaviours were observed, (i) a low shift of the absorption band due to coordination of the anions with the thiourea protons and (ii) the appearance of a new red shifted band due to deprotonation. [2] For the latter effect a change of the color solution from pale yellow to purple was observed. Fluorescence studies were also in agreement with the different effects observed in the UV/Vis titrations. In this case hydrogen bonding interactions were visible through the enhancement of the emission band, whereas in contrast deprotonation induced the appearance of a new red-shifted emission. Stability constants for the two processes (complex formation + deprotonation) for receptors 3a-f in the presence of fluoride and acetate anions were determined from spectrophotometric titrations.

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Figure 1.Structure of furyl tiosemicarbazone receptors 3a-f. [1] S. P. G. Costa, R. M. F. Batista, P. Cardoso, M. Belsley, M. M. M. Raposo, Eur. J. Org. Chem.2006, 17, 3938-3946; M. M. M. Raposo, B. García-Acosta, T. Ábalos, P. Calero, R. Martínez-Máñez, J. V. Ros-Lis, J. Soto, J. Org. Chem.2010, 75, 2922-2933. [2] D. Esteban-Gómez, L. Fabbrizzi, M. Licchelli, J. Org. Chem., 2005, 70, 5717-5720.

Keywords: Chromo-fluorogenic sensors, furyl thiosemicarbazone receptors, anion recognition

MS.B1.P.245 Facile Complexation of Tiara-Shaped Pd(II) Thiolate Cluster with Silver Ion Keita Seda,a Yukatsu Shichibu,a,b and Katsuaki Konishi,a,b aGraduate School of Environmental Science, Hokkaido University, Sapporo (Japan). bFaculty of Environmental Earth Science, Hokkaido University, Sapporo (Japan). E-mail: [email protected] Tiara-shaped macrocyclic systems of oligomeric metal thiolate [M(μ-SR)2]n have recently attracted attention due to their unique structural features and electronic properties. Much effort have been made on the syntheses and structural characterization, but there have been no examples of molecular recognition studies taking notice of the unique ring structures with an alternative arrangement of metal atoms and dual sulfur bridges. In this presentation, we provide the first example of host guest chemistry of tiara-cluster systems in the firm 1 : 1 complexation between sulfur-bridged palladium hexagon [Pd(SC12H25)2]6 (1) and Ag+ ion. 1 was synthesized from Na2PdCl4 and 1-dodecanethiol according to literature [1]. Upon titration with an acetonitrile solution of AgOTf, the UV-visible absorption spectrum of a dichloromethane solution of 1 (0.025 mM) showed notable changes (Fig. 1), where several clear isosbestic points were observed (e.g., 285 and 445 nm). Plots of the absorbance at 270 nm versus [Ag+]0 showed a clear inflection point at a [Ag+]0/[1]0 mole ratio of 1 : 1. Matrix-assisted laser desorption mass spectra (MALDI-TOFMS) of a mixture of 1 and AgOTf showed a main peak at 3164 assignable to the adduct 1·Ag+ (calcd, 3163). These observations indicate a strong one-to-one complexation between 1 and Ag+ with an association constant > 107. The clean and facile complexation is likely a result of effective chelating of multiple sulfur atoms of 1 with silver(I) ion. Actually, 1H NMR titration experiments revealed significant changes of the signals due to the SCH2 moieties. The high binding affinity of 1 towards silver(I) ion allowed efficient extraction of silver salt from aqueous phase to organic phase. When an aqueous solution of AgNO3 was mixed with 1 in dichloromethane, the separated organic phase exhibited an identical UV-visible absorption profile to that observed in the above homogeneous titration experiment.

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Fig. 1 (left) X-ray crystal structure of 1 and (right) spectroscopic titration of 1 with AgOTf in dichloromethane / acetonitrile at 25 °C. (inset) Plots of the absorbance change at 270 nm versus [Ag+]0/[1]0. [1] Z. Yang, A. B. Smetana, C. M. Sorensen, and K. J. Klabunde, Inorg. Chem., 2007, 46, 2427-2431.

Keywords: cluster, macrocycle, molecular recognition

MS.B1.P.246 Diastereoselective Synthesis of ΛΛΛΛ M4L6 Tetrahedral Cages Kiu-Chor Sham, Guoli Zheng, Yi Pan, Kai-Chung Lau, Shek-Man Yiu and Hoi-Lun Kwong* Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China. E-mail: [email protected] Stereoselectivity is an important factor in the synthesis of metal complexes.[1] It is especially crucial for the synthesis of polynuclear metal complexes as the number of possible isomers resulted from the synthesis increase exponentially with respect to the number of metal centers. Metallosupramolecular chemistry has provided a partial solution to this problem. For example, M4L6 tetrahedral cage as it contains four octahedral ML3 centers in which the configuration of all four centers are controlled in the formation of the three dimensional structure, though with achiral ligand two stereoisomers in a 1:1 ratio would still remain. Stereoselective formation of tetrahedral cages can be achieved by using chiral ligands.[2] ΛΛΛΛ M4L6 tetrahedral cages of manganese and zinc were synthesized by using chiral quaterpyridine L. Both X-ray crystal structures, and results of NMR studies of the Zn cages suggest that the cages have cavity, which can capture anion. Guest exchange study was carried on the manganese cage by using circular dichroism spectroscopy and mass spectroscopy.

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[1] T. Abe, K. Shinozaki, Inorg. Chem., 2005, 44,849. [2] T. Abe,T. Suzuki, K. Shinozaki, Inorg. Chem., 2010, 49,1794.

Keywords: Luminescence, Vapochromism, Isotope effect

MS.B1.P.248 [1] U. Knof, A. von Zelewsky, Angew. Chem. Int. Ed., 1999, 38, 302. [2] S. J. Dalgarno, N. P. Power, J. L. Atwood, Coor. Chem. Rev., 2008, 252, 825.

Keywords: supramolecular, anion sensing, stereoselectivity

MS.B1.P.247 Isotope Effect on Moisture Sensing: A New Class of Vapochromic Ru(dbb)2(CN)2 (dbb = 4,4’-di-t-butyl-2,2’-bipyridine) Crystal Kazuteru Shinozaki,a Kazuhiro Tenmyo,a Takayoshi Suzuki,b a Department of Nanosystem Science, Yokohama City University, Yokohama, (Japan). bDepartment of Chemistry, Okayama University, Okayama (Japan). E-mail: [email protected] We have investigated about the vapochromic behavior of Ru(dbb)2(CN)2·2H2O (dbb = 4,4’-di-t-butyl-2,2’-bipyridine) crystal. The reversible increase/decrease in lifetime and blue/red shift in emission spectrum due to the stepwise sorption/desorption of water vapor were observed under H2O atmosphere [1], [2]. In this study, we observed a difference between D2O and H2O vapors in the vapochromism. A ratio of emission lifetimes of Ru(dbb)2(CN)2·2D2O and Ru(dbb)2(CN)2·2H2O was tD/tH = 1.14, and that of Ru(dbb)2(CN)2·D2O and Ru(dbb)2(CN)2·H2O was evaluated as a much smaller value tD/tH = 1.05 at a low vapor pressure. The result indicated that the easily released water molecule effectively contributed to the isotope effect on emission lifetime. An X-ray crystallography for Ru(dbb)2(CN)2·2H2O single crystal showed two crystallographically independent water molecules in an asymmetric unit. As shown in Figure, all water molecules were attached to CN group via hydrogen– bonding and classified into two groups of Waters A and B by O···N length and O···N–C angle; O(Water A)···N = 3.004 Å, O(Water A)···N–C = 174.86° and O(Water B)···N = 2.784 Å, O(Water B)···N–C = 136.55°. For Water A, another hydrogen–bonding to CN ligand of an adjacent complex molecule (O···N = 3.157 Å) was seen. These data suggest that the greater number of hydrogen-bonds to CN for each of the water A molecules might be expected to result in greater stability toward desorption from crystal by heating or evacuating than Water B.

Photophysics of Ruthenium(II) Polypyridyl Supramolecular Complexes linked with Gold(I) or Platinum(II) Organometallics Michito Shiotsuka,a Naoki Nishiko,a Hiroshi Kondo,a Katsuya Sako,a Koichi Nozaki,b aGraduate School of Engineering, Nagoya Institute of Technology, Aichi, (Japapn). bGraduate School of Science and Engineering, University of Toyama, Toyama (Japan). E-mail:michito@ nitech.ac.jp The design of supramolecular systems by the photoactive ruthenium(II) complexes has been extensively pursued owing to potential applications in photonic devices. Platinum(II) and gold(I) complexes have been also intriguing because of their unique luminescent properties. We have been firstly synthesized and researched in the photophysical properties of ruthenium(II) polypyridyl complexes containing 3-ethynylphenanthroline and 3,8-diethynylphenanthroline linked by gold(I) ion organometallics, triads Ru(II)-Au(I)-Ru(II) [1] and H-Ru(II)-Au(I)-Ru(II)-H. We demonstrate that these hybrid supramolecular complexes constructed with ruthenium(II) polypyridyl and gold(I) bis-acetylide units convert a metal perturbed p-p* phosphorescence into the MLCT-based phosphorescence after the photo-absorption. However, more repeated Ru(II)-Au(I) supramolecular complexes were unobtainable. Therefore, we made an attempt to the synthesis of novel ruthenium(II)-platinum(II) supramolecular systems with mono- or diethynylphenanthroline and platinum(II) bis-tributylphosphine, Ru(II)Pt(II)-Ru(II) [1] and H-Ru(II)-Pt(II)-Ru(II)-H, and were exploring the photoinduced energy transfer process and the electron population under the photo-excited state in these systems. In this symposium, we report the synthesis of new more repeated type of supramolecular complex, H-Ru(II)-Pt(II)-Ru(II)Pt(II)-Ru(II)-H (see scheme 1), which are constructed from three ruthenium(II) polypyridyl complex units and two platinum(II) bis-tributylphosphine organometallic units and the photophysical properties of these supramolecular complexes linked with gold(I) or platinum(II) organometallics. Photophysical data of all complexes suggest an efficient energy transfer from metal bis-acetylide complex site to one of the ruthenium polypyridyl complex sites followed by the supposed charge injection from a ruthenium center to the extended p-conjugated phenanthroline under the excited state in present supramolecular system. The transient differential absorption spectra of H-Ru(II)-Pt(II)Ru(II)-H and H-Ru(II)-Pt(II)-Ru(II)-Pt(II)-Ru(II)-H were showed the distinctive breaching of the p–p* and MLCT absorption band, and an intensive absorption band in the region of 500-700 nm, which is probably assignable to p–p*(diethynyl phenanthroline radical) absorption.

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Poster Sessions MS.B1.P.251 Water-Nanotube Cluster like Chrathrate Hydrate Stabilized in Molecular Nanoporous Framework Makoto Tadokoro,a Hiroshi Matsui,b aDepartment of Chemistry, Tokyo University of Science, Tokyo, (Japan). bDepartment of Physical Science, Tohoku University, Sendai (Japan). E-mail: tadokoro@ rs.kagu.tus.ac.jp [1] M. Shiotsuka, N. Nishiko, K. Keyaki, K. Nozaki, Dalton Trans, 2010, 39, 1831-1835.

Keywords: ruthenium, phosphorescence, platinum

MS.B1.P.249 Molecular Computing Marketa Smidkova,a Edwin C. Constable,a Catherine E. Housecroft,a Alberto Credi,b aDepartment of Chemistry, University of Basel, Basel (Switzerland). bDepartment of Chemistry, University of Bologna, Bologna (Italy). E-mail: [email protected] Certain compounds can work as so-called molecular switches. Inherent properties of molecules such as conformation, isomerisation, redox properties, pH sensitivity, photoinduced electron transfer and photophysics form the basis of the input and outputs, desirable in a molecular computational device. Our group has reported molecular switching properties of ruthenium(II) terpyridine metal complexes with pendant pyridine units which can exist in different protonation states, each displaying different photophysical characteristics. By observing the change in luminescence is it possible to construct logic gates. The aim of this project is to synthesise heteroleptic ruthenium(II) complexes with a halogen or a methyl ester substituted pyridyl-terpy ligand. This functionality allows one to further modify the complex with a long side chain containing a secondary or tertiary amine unit which will act as an additional proton acceptor site. Each protonation state of the ruthenium(II) complex displays different photophysical characteristics in the emission spectra, which forms the basis for OR and AND logic gates of molecular switches.

Investigation of some water-molecule clusters formed in the interstitial space of supramolecular crystals has attracted attention as an important method to understand the behavior of bulk water and ice. However, since most of the water clusters are actually small in unit cell and stabilized by direct H-bonding with supramolecules, they display no macroscopic behavior of bulk water such as a phase transition and a glass one. We have constructed huge water clusters in porous molecular crystals with one-dimensional nanochannels by selforganization of designed molecular building blocks of [Ru(H2bim)3]3+ (Hbim– = biimidazolate) complexes and TMA3– (trimesate) ions. The water nanotube clusters (WNTs) in the channel spaces show a structural phase transition, and the crystal structure of WNT corresponding to the melting state is also observed. Interestingly, the crystal structure of WNT, stabilized by H bonds with porous outer walls is constructed from a partial structure {51262}n of type-I clathrate hydrates. Figures 1a and 1b show the crystal structure of the WNT along the b and c axes, respectively, obtained by X-ray structure analysis at 20 °C, after the phase transition from the ice to the melting state. The connecting structure of water oxygen atoms in the WNT is also shown. The structural unit of a 51262 tetradecahedron consists of twenty water molecules, which form two six-membered rings and twelve fivemembered rings that H-bond with two water molecules in the unit. The two faces of six- membered rings of consecutive 51262 units joined end to end form a 1-D tube-like {51262}n structure. The water oxygen atoms (O(4), O(4)*, O(5), O(5)*, O(6), and O(6)*) of the primary hydrate sphere in the WNT, which might be directly connected to the carboxylic oxygen atoms.

Figure 1. Crystal structure of WNT of 1 (a) along the b axis and (b) along the c axis. [1] S. Sisvi, E. C. Constable, C. E. Housecroft, J. E. Beves, E. L. Dunphy, M. Tomasulo, F. M. Raymo and A. Credi, Chem. Eur. J., 2009, 15, 178.

Keywords: ruthenium(II) complex, molecular switches, terpyridine

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[1] M. Tadokoro, et al., Chem. Lett., 2010, 39, 186-187.[2] M. Tadokoro, et al., J. Phys. Chem. B, 2010, 114, 2091-2099. [3] H. Matsui, and M. Tadokoro, et al., J. Phys. Soc. Jp., 2010, 79, 103601-4.

Keywords: proton conductivity, clathrate hydrate, porous framework

MS.B1.P.252

MS.B1.P.253

Twisting of a Tetrasubstituted Olefin via Inclusion in a TdSymmetric Cage Hiroki Takezawa,a Takashi Murase,a Makoto Fujita,a,b aDepartment of Applied Chemistry, School of Engineering, The University of Tokyo (Japan). bCREST, Japan Science and Technology Agency (JST) (Japan). E-mail: [email protected]

Diradical Complex Recognizing the Size of Microenvironment Kousaku Tamura, Atsuko Masuya, Nobuhiko Iki, Hitoshi Hoshino, Graduate School of Environmental Studies, Tohoku University (Japan) E-mail: [email protected].

Tetrasubstituted olefins with bulky substituents have two major conformers: anti-folded and twisted ones. They show different optical and chemical properties. Especially, twisted ones have distinct properties (e.g. absorption in visible region) from typical olefins because of their highly distorted C=C bond. Under thermal or photo stimuli, these conformers are usually in equilibrium, and the dynamic behaviors are difficult to predict and control. Here, we report that Td-symmetric self-assembled cage 1 traps the twisted conformer of tetrasubstituted olefin 2 and alters its optical properties and reactivities. Unusual bromination of the noncovalently-twisted olefin yielded a highly twisted one locked by bromines. Tetrasubstituted olefin 2 has anti-folded conformation in solid state, as evidenced by the yellow color.[1] When solid 2 was suspended in an aqueous solution of cage 1 and the mixture was irradiated with microwave at 100 ºC for 1 h, the solution turned deep purple. The color change suggested the inclusion of olefin 2 in cage 1 and its conformational change from the anti-folded to the twisted form. After dryness, the powdered inclusion complex 1•2 remained deep purple. Thus, the twisted conformation was stable within 1 even in solid state. The fixed twisted olefin 2 in the cavity of cage 1 showed unusual reactivity towards bromination. When N-bromosuccinimide (NBS, 2.0 eq.) was added to an aqueous solution of inclusion complex 1•2, the solution color immediately changed from deep purple to green. After extraction from cage 1, deep-blue tetrabrominated product 3 was obtained. The reaction of free 2 with NBS did not give product 3. X-ray crystallography revealed the highly twisted structure of olefin. The isomerizatin into the anti-folded form of 3 was sterically forbidden. Thus, anti-folded conformer of 2 was converted to highly twisted olefin 3 by the unusual bromination within cage 1.

We have investigated application of diradical complexes of d8metal ions to recognize hydrophobicity and pH of solution medium by means of their characteristic absorption in near-infrared (NIR) region [1,2]. Recently, we found that 3,4-diaminobenzoic acid (DBA) formed a diradical complex [PtII(LISQ)2]2- with PtII ion in alkaline aqueous solutions (LISQ: o-iminobenzosemiquinonate form of DBA) to exibit strong absorption band at 716 nm (8.0 × 104 M-1cm-1) [3]. By contrast, in acidic solutions, the NIR absorption disappeared by oxidation of the complex followed by dimerization to {[PtII(LISQ)(LIBQ)]2}2- (LIBQ: o-iminobenzoquinonate form of DBA). Thus, [PtII(LISQ)2]2- can act as a pH sensor. However, the response of this complex upon increasing pH from low pH region was irreversible, possibly due to the slow rate of dissociation of {[PtII(LISQ)(LIBQ)]2}2- to monomer [PtII(LISQ)(LIBQ)]-. Therefore, prevention of formation of the dimer is the key to improve the response ability. In view of isolating the complex in nanospace to hinder dimerization, we employed cyclodextrins (CD) to include the complex. Herein we report the unexpected finding of [PtII(LISQ)2]2capable of distinguishing the size of CDs. In alkaline aqueous solution, [PtII(LISQ)2]2- and β-CD formed an inclusion compound [[PtII(LISQ)2]2- ⊂ (β-CD)2] (Fig. 1 left), the composition of which was confirmed by NMR measurements. In contrast, [PtII(LISQ)2]2- and g-CD formed a 2 : 1 (= [PtII]Total : g-CD) inclusion compounds, the composition of which was confirmed by spectrophotometry. In this case NIR absorption at 716 nm characteristic of diradical complex disappeared, and a new NIR absorption band at 850 nm characteristic of dimerized complex {[PtII(LISQ)(LIBQ)]2}2appeared. Thus we concluded that γ-CD induced dimerization to form {[PtII(LISQ)(LIBQ)]2}2- by inclusion into the large cavity (Fig. 1 right). Furthermore, cyclic voltammetry of complex was recorded in the presence of β- or g-CD in the aqueous solution. As a result, β-CD caused positive shift in the peak potential for [PtII(LISQ)2]2- oxidation, suggesting that β-CD inhibits oxidation of complex by inclusion and cannot afford accommodation of {[PtII(LISQ)(LIBQ)]2}2-. In contrast, g-CD caused decrease in the peak current for [PtII(LISQ)2]2- oxidation, because the oxidized species was pre-formed by inclusion into g-CD. The sharp contrast of inclusion, oxidation, and NIR absorption of [PtII(LISQ)2]2- into b- and g-CD in turn means that it has size-recognition ability which can be applied to the probe recognizing subtle difference of the size of microenvironment.

Fig. 1 Left: [[PtII(LISQ)2]2- ⊂ (β-CD)2] complex. Right: [{[PtII(LISQ)(LIBQ)]2}2- ⊂ γ-CD] complex.

[1] P. U. Biedermann, J. J. Stezowski, I. Agranat, Chem. Eur. J. 2006, 12, 3345– 3354.

Keywords: self-assembly, chromism, conformation control Fig. 2 UV/vis spectral change of [PtII(LISQ)2]2- upon addition of g-CD in aqueous solution. [[PtII(LISQ)2]2-] = 5.0 × 10-5 M, [g-CD] = 0.01 M, pH 12.20.

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P.MS.B1

Poster Sessions

Poster Sessions [1] Y. Terazono, Ph. D Thesis, Tohoku University, 1999. [2] A. Masuya, N. Iki, C. Kabuto, Y. Ohba, S. Yamauchi and H. Hoshino, Eur. J. Inorg. Chem., 2010, 22, 3458. [3] K. Tamura, A. Masuya, N. Iki, Y. Ohba, S. Yamauchi and H. Hoshino, Inorg. Chim. Acta, 2012, 378, 81.

Keywords: Diradical complex, cyclodextrin, size recognition

MS.B1.P.254 Cyclotriguaiacylene Ligands for Synthesis of MetalloSupramolecular Assemblies Flora Thorp-Greenwood,a Michaele Hardie,b (Department of Inorganic Chemistry, University of Leeds, Leeds, England). E-mail: chmft@ leeds.ac.uk CTG is an analogue of cyclotriveratrylene, akin to the calixarene family of compounds, with three methyl groups removed to reveal three hydroxyl groups (see structure below) on which chemistry can be performed to yield specialised ligands for the binding of metals and organic molecules. This work describes the synthesis of novel CTGbased cavitands appended with various tridentate heteroleptic donors including pyridine, pyrazole, thiophene and amine functionalities. The ligand donors are incorporated through ester, amide and ether appendages to the upper rim hydroxyl groups associated with the CTG-core to infer limited flexibility and retain the bowl-shaped cavity into which the encapsulation of small molecules may be possible. The binding of Xe has already been demonstrated with similar ligands [1], so mono- and diatomic molecules are expected to show encapsulation not only in the solid state, but also to some extent in solution. The new CTG-functionalised ligands described in this work have been treated with various transition metal salts, concentrating on metals with a preference for square-planar geometries such as PtII or PdII, so once coordinated to the tridentate donors, only one vacant coordination site remains, to allow intermolecular interactions between complexes in an attempt to form higher order structures. Such structures include discrete capsule-shaped cryptophanes by the assembly of two cavitands in a head-to-head fashion, or the formation of coordination polymers which have the potential for post-synthetic modification. The applications of these metallo-assemblies in hostguest chemistry, catalysis and their scope as nano-reaction vessels will be investigated to discover the potential uses of these structures. It is also within the scope of this project to incorporate linear linkers such as 4,4’-bipyridine or linear porphrins or salen-type ligands to synthesis extended stuctures where the CTG core can act as the three-armed vertices of a cube with the linear linkers making the twelve edges of the cube to create larger void spaces within the discrete 3D structures in which chemistry can be performed or influenced for potential regio- and stereo-control in asymmetric catalysis. The “Solomon’s cube” structure has already been isolated within the group with other ridgid ligands [2], so this is a real possibility with these novel CTG-functionalised systems.

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[1] P. A. Hill, Q. Wei, T. Troxler, and I. J. Dmochowski, J. Am. Chem. Soc., 2009, 131, 3069-3077. [2] T. K. Ronson, J. Fisher, L. P. Harding, P. J. Rizkallah, J. E. Warren,. M. J. Hardie, Nature Chemistry, 2009, 1, 212-216.

Keywords: Metallo-supramolecular, cavitand, host-guest

MS.B1.P.255 Tetrahedral Cage of Chiral Tetradentate Pyridylthiazole Ligand: Synthesis, Characterization and X-Ray Crystal Structures Chiu-Shan Tsang, Chi-Chung Yee, Shek-Man Yiu, Hoi-Lun Kwong,* Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR (China) Fax: 852 3442 0522; Tel: 852 3442 7304. E-mail: [email protected] In the design of supramolecular structures, metal–ligand interaction is of particular interest because it is predicable and controllable based on the encoded information of ligands and metal ions.[1] Although various approaches have been employed, the directional bonding approach[2,3] is a very popular one. The angle between binding units in a ligand strand is of great importance in the construction of a well-defined supramolecular structure because the angle can provide directionality upon coordination with metal ions.[4] The study of the effect of the directional angle in a polydentate ligand on the formation of supramolecular structures is less clear because the angle in a polydentate ligand is less well-defined as it can be affected by the twisting of binding units and, upon coordination, the geometry of the metal ion. We have previously reported a chiral tetradentate pyridylthiazole ligand which has two bidentate pyridyl-thiazole binding domains for the complexation of Cu(I) to result in a dinuclear double-stranded helicate. [5] To explore the effect of the directional angle of a polydentate ligand on the formation of supramolecular structures, new chiral tetradentate pyridylthiazole ligand L, based on (-)-nopinone, was synthesized. It is a ditropic ligand very similar to the previously reported one but are coupled at different position. With the new ligand, two tetrahedral cages, with Ni and Cd, are reported.

Poster Sessions

P.MS.B1

region than with 1. However, the extraction of In3+ was not observed with 2 and 3. It was reported that the extractions of the group 13 metal ions are subject to the effect of the inter-ligand contact and the bite size (the O-O distance) [1]. The extraction of In3+ was not made with 2 and 3 having shorter bite size. The quantitative separation of Al and Ga from In can be achieved using 2 and 3 as the extraction reagent. The effect of the inter-ligand contact was not observed in the present work with 1 -3.

Figure 1 Structures of the cycloalkanones

Figure 1. (left) The ORTEP plot of cationic structure of [Ni4(L)6] showing one of the ligand strand and the perchlorate which is located on the face of the tetrahedron. H atoms and counterions are removed for clarity. (right) Spacefilling structure of [Ni4(L)6]8+ with colored ligand strands. 8+

[1] Alexeev, Y. E.; Kharisov, B. I.; Hernández García, T. C.; Garnovskii, A. D. Coord. Chem. Rev. 2010, 254, 794. [2] Fujita, M. Chem. Soc. Rev. 1998, 27, 417. [3] Stang, P. J.; Olenyuk, B. Acc. Chem. Res. 1997, 30, 502. [4] Chakrabarty, R.; Mukherjee, P. S.; Stang, P. J. Chem. Rev. 2011, 111, 6810. [5] Tsang, C.-S.; Yeung, H.-L.; Wong, W.-T.; Kwong, H.-L. Chem. Commun. 2009, 1999.

Keywords: supramolecular, tetrahedral cage, stereoselectivity

MS.B1.P.256 Selective Recognition of Group 13 Metal Ions (Al3+, Ga3+, In3+) with Trifluoroacetylcycloalkanones Shigeo Umetani, Yukari Sasaki, Yoshiki Sohrin, Institute for Chemical Research, Kyoto University, Kyoto (Japan). E-mail: umetani@scl. kyoto-u.ac.jp Trifluoroacetylcyclopentanone (1), -cyclohexanone (2) and -cycloheptanone (3) have been synthesized (Figure 1) and the complexation with group 13 metal ions (Al3+, Ga3+, In3+) has been investigated via the solvent extraction technique. The strength of the intramolecular hydrogen bond was found to depend on the distance between the two donating oxygen atoms in the enol form estimated by density functional theory (B3LYP/6-31G(d,p)). The O-O distance for 1 is larger than those for 2 and 3 as predicted from their cyclic structures. The strength of the intramolecular hydrogen bond increases in the order, 1 < 2 ≈ 3, which is also supported by 1H NMR. The very broad peak assigned to the enolic proton (-OH) for 1 appears at 12.95 ppm, while those for 2 and 3 are very sharp and shift downfield to 15.07 and 15.93 ppm, respectively. These signals did not move through changing the concentration (0.01 - 0.1 mol dm-3) and was found to disappear after adding D2O. The acid dissociation constants (pKa) were measured by the two phase distribution method. The pKa values increase in the order, 1 < 2 < 3, reflecting the strength of the intramolecular hydrogen bond. Group 13 metal ions were readily extracted to the chloroform phase from the aqueous phase with 1 in the order, Ga3+ > Al3+ > In3+, which is usually seen in the solvent extraction with the conventional β-diketones. The extractions with 1 were made in the lower pH region than those with 2 and 3 owing to the stronger acidity of 1. Al3+ and Ga3+ were extracted with 2 and 3 in the order Ga3+ > Al3+ in the higher pH

[1] Q. T. H. Le, S. Umetani, M. Matsui, J. Chem. Soc., Dalton Trans., 1997, 3835-3840.

Keywords: group 13 metal ions, selective recognition, solvent extraction

MS.B1.P.257 Structural Conversion of A Tripalladium(II) Complex with d-Penicillamine Anzu Yokoi, Yusuke Hirai, Nobuto Yoshinari, Asako IgashiraKamiyama, Takumi Konno, Department of Chemistry, Graduate School of Science, Osaka University, Osaka (Japan). E-mail: konno@ chem.sci.osaka-u.ac.jp The development of coordination chemistry involving [M(amine)2(thiolato)2]-type (M = NiII, PdII, PtII) square-planar species has been driven by their utility as an S-donating metalloligand for the construction of S-bridged multinuclear structures, as well as their structural relevance to the active centers of nickel-containing metalloproteins. To date, a number of [NiII(amine)2(thiolato)2]-type complexes have been prepared and their structures and properties have been extensively investigated. On the other hand, studies on the corresponding PdII complexes are much less common mainly because of the difficulty in isolating these species in a monomeric form. For example, it has been shown that the reaction of [PdCl4]2– with d-penicillamine (d-H2pen) in water produces an S-bridged tetranuclear complex, [Pd4Cl4(d-Hpen)4], which is convertible to an S-bridged trinuclear complex, [Pd3(d-pen)3].[1] Herein, we report that [Pd3(d-pen)3] is converted to a mononuclear structure in [Pd(d-pen)2]2– by treating with d-penicillamine. The reactions of [Pd3(d-pen)3] with another sulfur-containing amino acid will also be reported.

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Poster Sessions [1] J. Yoshida, H. Sato, N. Hoshino, A. Yamagishi, J. Phys. Chem. B, 2008, 112, 9677-9683.

Keywords: D, L isomers, liquid crystal, chiral dopant

MS.B1.P.259 Metallosupramolecular Structures Composed of d-Penicillaminato CuI8CuII6 Cluster Nobuto Yoshinari, Asako Igashira-Kamiyama, Takumi Konno, Department of Chemistry, Graduate School of Science, Osaka University, Osaka (Japan). E-mail: [email protected] [1] N. Yoshinari, Y. Hirai, T. Kawamoto, A. Igasihra-Kamiyama, K. Tsuge, T. Konno, Chem. Lett., 2009, 38, 1056-1057. Keywords: Sulfur-containing amino acids, Palladium(II) complex, S-Bridged structures

MS.B1.P.258 Induction of Chiral Nematic Phases by the Use of D, L-tris(bdiketonato)Ru(III) complexes Jun Yoshida, Hidetaka Yuge, Kitasato University, Japan, E-mail: [email protected] Nematic liquid crystal (N) phases are known to transform to chiral nematic liquid crystal (N* or cholesteric liquid crystal) phases on doping a small amount of chiral molecules (chiral dopants). This phenomenon is interesting as a chiral amplification as well as the basic mechanism of liquid crystal display. Chiral dopants so far examined are organic compounds in most cases. Organic chiral dopants are superior in the sense of flexibility and structural versatility. In contrast, we have examined the use D, L-tris(b-diketonato)Ru(III) complexes as chiral dopants with rigid structure.[1] In this presentation, we propose two types of dopants, which were designed to be elongated perpendicular to and in parallel with the molecular C2 axis. [Ru(acac)2(Lper)] (acac = acetylacetonato, Lper = 1,3-didodecyloxyphenyl-1,3-propanedionato) and [Ru(acac)2(Lpara)] (Lpara = 3-[4’-decyloxyphenyl]pentane-2,4-dionato) were synthesized and optically resolved into pure enantiomers. Resultant enantiomeric complexes were used as chiral dopants for four nematic liquid crystals. D-[Ru(acac)2(Lper)] induced M-helix in every liquid crystals, while D-[Ru(acac)2(Lpara)] induced P-helix. Induced helix is reversed between the two complexes with the same chirality. The direction of Lper and Lpara in the dopants with rigid structure probably determines the ordering direction in liquid crystals. We are also examining the synthesis and optical resolution of [Ru(acac)(Lpara)2] and [Ru(Lpara)3]. Correlation between the substituents of the acac ligands and induced helical structure will be discussed.

It has been recognized that a mononuclear cobalt(III) complex, K[Co(d-pen)2] (d-H2pen = d-penicillamine), acts as an S-donating metalloligand available for the construction of S-bridged polynuclear structures. For example, this complex has been shown to react readily with AuI or AgI to give S-bridged CoIIIMI complexes, [M3{Co(d-pen)2}3] (MI = AuI, AgI).[1] On the other hand, we have recently found that the reaction of K[Co(d-pen)2] with CuCl2 produce a heptacopper(II) cluster with a corner-sharing double cubane structure, [Cu7(μ3OH)6(μ3-Cl)2(d-pends)2] (d-H2pends = d-penicillaminedisulfide).[2] This result prompted us to investigate the reaction of K[Co(d-pen)2] with CuCl, which is expected to show different redox behavior. Herein, we report that this reaction does not give a simple thiolato-bridged CoIIICuI compound, but produces a fascinating metallosupramolecular compound consisting of thiolato-bridged CuI8CuII6 clusters, [CuI8CuII6(d-pen)12Cl]5–, that are linked by CoII and/or KI ions. Remarkably, three types of metallosupramolecular compounds with different dimensional structures were constructed only by a slight change in the buffer solutions used for the reactions. This is thanks to the presence of 12 free carboxyl groups in [Cu14(d-pen)12Cl]5–, the binding modes of which can be controlled by the solution pH, as well as by metal ions co-existed in solution.

[1] T. Konno, Bull. Chem. Soc. Jpn. 2004, 77, 627-649. [2] A. IgashiraKamiyama, J. Fujioka, S. Mitsunaga, M. Nakano, T. Kawamoto, T. Konno, Chem. Eur. J. 2008, 14, 9512-9515.

Keywords: Supramolecular chemistry, S-bridged structures, Redox reaction

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Poster Sessions

Europium(III) Mixed Ligand Complexes as a Basis for Luminescent Nanoparticles Rustem Zairov, Natalia Shamsutdinova, Dmitry Tatarinov, Asiya Mustafina, A.E.Arbuzov Institute of Organic and Physic Chemistry KSC RAS, Kazan, (Russia). E-mail: [email protected] In recent years nanoparticles have been the top of interest for researchers due to their applications in medicine and biology. The synthesis of nanoparticles with a core-shell architecture is the most recent trend in the nanotechnology field, since it expands the number of materials suitable for nanofabrication and enables to improve nanoparticles properties (lowering of quantum dots toxicity, improving of colloidal stability etc.) Core-shell nanoparticles are highly functional materials with tunable properties. Sometimes properties arising from either core or shell materials can be quite different resulting in the two or more functions inside one nanoparticle. Their properties can be modified by changing either the constituting materials or the core to shell ratio. That is why many examples of the core-shell nanoparticles applicability in bioanalysis, therapy and diagnostics can be found in the literature. We obtained novel highly-luminescent core-shell NP on the basis of europium(III) thenoyltrifluoroacetonate adduct with 2-(5-chlorophenyl-2-hydroxy)-2phenylethenyl-bis-(2methoxyphenyl)phosphine oxide. The Eu(III) complex reprecipitated from organic solvent to water forms the core of NP and the shell is built from oppositely charged polyelectrolyte (PE) layers. The negatively charged poly(sodium 4-styrenesulfonate) (PSS) was applied as the first layer. Positively charged polyethyleneimine (PEI) was deposited on PSS coated particles resulting in recharging of the surface of NP from minus to plus. Further layer-by-layer PE deposition enables to get up to six layers onto luminescent template. Photophysical properties, size and electrokinetic potential of NPs with the various number of PE layers in aqueous solutions indicate that the obtained colloids exhibit high colloidal stability. Moreover their quantum yields and lifetimes of the excited states are greater than for silica coated Eu(III) complexes. Microscopy images of dried NPs confirm their core-shell morphology. Our results represent the synthetic route to insert of d-metal ions and SPIONs into the polyelectrolyte multilayer fabricated onto Eu(III) complex core. The lack of the ion exchange between metal ions located within the core and the shell is the great advantage of this core-shell morphology, since it enables to combine magnetic or magnetic-relaxation and luminescent or dual luminescent functions within each nanoparticle. Acknowledgement: RFBR (grant 10-03-00352a) and Young Doctors grant (МК-4617.2013.3)

Keywords: europium(III) complex, core-shell nanoparticles, luminescence

MS.B2.P.261 Iridium-Containing Polyoxometalates: Synthesis, Structure and Reactivity Sergey A. Adonina,b, P.A. Sinkevich,a,b Maxim N. Sokolova,b and Vladimir P. Fedina,b, aNikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia. bNovosibirsk State University, Novosibirsk, Russia. E-mail: [email protected] Noble metal-containing polyoxometalates (POM) represent an area which attracts a keen attention of various research groups due to a number of interesting properties, such as catalytic oxidation of water and/or various organic substrates, transfer of nitrogen etc. Among them, complexes of POM with iridium remain little studied. Here we report the results of our recent work on synthesis and studies of Ir-containing POMs. Complex of Ir with lacunary polyoxotungstate with Keggin structure, [PW11O39Ir(H2O)]4- (1) has been obtained by hydrothermal reaction of [PW11O39]7- and K2IrF6. The compound has been characterized by various methods (ESI-MS, NMR, cyclic voltammetry etc.); the substututional lability of aqua ligand is studied by ESIMS1. Complex 1 reacts with Me3SnCl under harsh conditions to give organometallic derivative, [PW11O39Ir-CH3]5- (2) and with NCS- to give [PW11O39Ir-SCN]5- (3) with S-bonded thiocyanate. The use of Sn(II) as two-electronic reductant and K2IrCl6 as Ir source allowed us to obtain two POM complexes with rare {Ir2}4+ cluster core (figure). Both complexes have been characterized by X-ray structural analysis:

Both [(PW11O39Ir2(H2O)2]10- (left, 4) and [(W5O18)2Ir2(H2O)2]8- (right, 5) may be considered as sandwich-type complexes with lacunary Keggin and Linqvist units, respectively.

The oxidation state of Ir is Ir(II); therefore, rare cluster unit {Ir2}4+ is isoelectronic with the well-known {Rh2}4+ core. Terminal positions are occupied by aqua ligands. Reaction of K2IrF6 with Na2WO4 in slightly acidic media results in self-assembly of Anderson-type polyoxoanion [IrW6O24]8- (6). In this case (contrary to 1) Ir preserves its original oxidation state (IV). Complex 6 is isostructural with the corresponding Pt(IV)-containing POM. [1] M.N. Sokolov, S.A. Adonin, D.A. Mainichev et al. Chem. Commun. 2011, 47, 7833.

Keywords: Polyoxometalates, Noble metals, Clusters

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MS.B1.P.260

Poster Sessions MS.B2.P.262 Mixed-Valence Polyoxometalates: Use of Symmetry in the Dynamic Vibronic Problem Juan M. Clemente-Juan,a Alejandro Gaita-Ariño,a Eugenio Coronadoa, Andrew Paliib, Boris Tsukerblatc, aInstituto de Ciencia Molecular, Universidad de Valencia (Spain), bInstitute of Applied Physics, Academy of Sciences of Moldova (Moldova), cChemistry Department, Ben-Gurion University of the Negev (Israel). E-mail: [email protected] The 2e-reduced mixed-valence dodecanuclear Keggin anion in which the electronic pair is delocalized over twelve sites (overall symmetry Td) exhibits unusual magnetic properties and in particular, unexpected antiferromagnetic coupling between “blue” electrons. This was previously interpreted as a consequence of the electronic delocalization that, in turn, should be considered along with the vibronic coupling. Within the so-called PKS model one faces an multilevel/ multimode vibronic problems of the types of (1T2+1E+1A1)⊗(e+t2) and (3T1+3T2)⊗(e+t2) for the spin-singlet and spin-triplet low lying states of the electronic pair delocalized over twelve sites in Keggin structure. For the dodecanuclear Keggin anion which belong to class II in the Robin-Day scheme the failure of the Born- Oppenheimer approximation does not allow to adequately use the concept of the adiabatic surfaces and in particular the charge transfer transitions can not longer be interpreted as a transition between two potential surfaces. Here we present a theoretical approach and an efficient computer program aimed to the accurate solution of the dynamic vibronic problem in large scale mixed-valence systems. The algorithm for the solution of the eigen-problem takes full advantage of the point symmetry arguments [1]. The procedure includes two steps: first, the evaluation of wave-functions with a given symmetry and, second, coupling with the electronic functions to get full basis set. Within the symmetry adapted electron-vibrational basis the full matrix of the Hamiltonian is blocked according to the irreducible representations of the point group that allows one to essentially simplify the problem. The proposed approach is a part of our study of the nanosized mixed valence clusters with large number of delocalized electrons that are at the border line between quantum and classical objects. [1] B. Tsukerblat, A. Palii, , J.M. Clemente-Juan, A. Gaita-Ariño, E. Coronado, Int. J. Quantum Chemistry, 2012, DOI: 10.1002/qua.24152.

Keywords: polyoxomelates, mixed-valence, vibronic coupling

MS.B2.P.263 The structure of Silica-supported Preyssler Nanoparticles H14 [NaP5W30O110]/SiO2 Ali Ghariba,b M. Jahangir,a a Department of Chemistry, Islamic Azad University, Mashhad, Iran, [email protected], bAgricultural Researches and Services Center, Mashhad-IRAN. E-mail: aligharib5@ yahoo.com The first time in this research, heteropolyacid H14[NaP5W30O110]/ SiO2 nanoparticles were synthesized by a microemulsion technique. Various morphologies including nanotubes and nanowires were obtained by controlling the molar ratio and time during the synthesis. In a designed photoreactor by our research group, the photodegradation of methylorange as common azo dye pollutants in the environment was selected as a test reaction to estimate the catalytic activity of synthesized nanoparticles. Our findings showed that, the catalytic activity of nanoparticles is very excellent. Heteropoly compounds are by far more important for catalysis as well as for other applications. These properties make some difficulties in catalyst recovery and catalyst

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life. The present research illustrates the synthesis of nanoparticles H14 [NaP5W30O110]/SiO2 having various morphologies by controlling the molar ratio of water to surfactant as well as reaction time. The catalytic activity over the immobilized heteropolyacid was evaluated by the photo-degradation of methyl orange in a designed Photoreactor by our research group. The sodium 30-tungstopentaphosphate/ SiO2 nanoparticles was successfully obtained in our work. In a designed photoreactor by our research team, photodegradation of methylorange as an azo dye was investigated. The concentrations of methylorange were quantified by UV-vis spectroscopy and percentage of decolorization was calculated. The structure of Preyssler nanoparticles shows a typical photodegradation under the influence of nanoparticles. H14[NaP5W30O110]/SiO2 nanoparticles with different sizes and morphologies could be synthesized by varying the molar ratio of water/surfactant via microemulsion technique. The study for photocatalytic activity of the nanoparticles shows an excellent activity for photodegradation and decolorization of methyl orange. [1] P. Souchay, Ions Mineraux Condenses, Masson, Paris, 1969. [2] T. Okuhara, N. Mizuno, M. Misono, Appl. Catal, A: Gen, 2001, 222, 63. [3] A. S. Dias, S. Lima, M. Pillinger, A. A. Valente, Carbohydrate Res, 2006, 341, 2946. [4] D. Varisli, T. Dogu, G. Dogu, Chem. Eng. Sci, 2007, 62, 5349.

Keywords: Preyssler, Nanoparticles, Catalyst

MS.B2.P.264 The Coordination Compounds of Preyssler Heteropolyanions as Nanocatalysts Ali Gharib1,2,*, Manochehr Jahangir1, Mina Roshani,1 1 Department of Chemistry, Islamic Azad University, Mashhad, IRAN and 2 Agricultural researches and services Center, Mashhad, IRAN. E-mail: aligharib5@ yahoo.com Polyoxometalates (POMs) are discrete molecular structures composed of metal cations bridged by oxide anions. They are not multi-metal species with metal-metal bonding, one conventional definition of “clusters”, but they are clusters in the generic sense of the word. Although the basic structural principle for polyoxovanadates, molybdates, and tungstates is the samessince the structures are governed by the principle that each metal atom occupies an {MOx} coordination polyhedron, in which the metal atom is displaced, as a result of M-O δ-bonding, toward those polyhedral vertexes that form the surface of the structuresa more detailed view of this fascinating area of chemistry shows striking differences for the three compound types also with respect to the very large cluster systems discussed here. Heteropolyacid (HPA) compounds are the objective of research for a long time. The reactions catalyzed by them both in heterogeneous and homogeneous systems have been reviewed by many researchers [1]. Catalysis of keggin heteropolyacid has at tracted much interest since seventies. The heteropolyacid possesses the dual catalytic functions of strong acidity and oxidizing ability. HPA will be expected as an alternative acid catalyst to improve several organic processes which employ conventional acids [2]. In aqueous solution HPA such as PW, SiW, Preyssler”s anion and PMo are strong fully dissociated acids. HPAs in solution are stronger them the usual mineral acids such as HCl, Sulfuric acid, and etc [3]. HPAs are complex proton acid that incorporate polyoxometalate anions (heteropolyanions) having metaloxygen octahedra as the basic structural units and catalysis by them is a field of increasing importance [3]. [NaP5W30O110]14-, the socalled Preyssler’s anion, Na+ is encrypted inside a central cavity formed by five PW6O22 units arranged in a crown [4], as shown schematically in Fig. 1.

Poster Sessions the guiding principles for the deposition of POM anions in multilayers with respect to layer architecture, surface coverage, permeability, and electrochemistry.

Figure 1. Structure of [NaP5W30O110]14- polyhedral form showing WO6 octahedra and the central Na (open circle).

Figure 1. (Top) Coordination Polyhedra Representation of POM Figure 2. Anchored Nanoparticles: Nano Preyssler catalysts [1] T. Okuhara, N. Mizuno, M. Misono, Adv. Catal. 1996, 41, 113. [2] M. A. Schwegler, J. A. Peters, H. Van Bekkum, J. Mol. Catal. 1990, 63, 343. [3] S. Shikata, M. Misono, Chem. Commun. 1998, 12, 1293. [4] F. F. Bamoharram, M. M. Heravi, M. Roshani, M. A. Gharib, M. Jahangir, J. Mol. Catal. A: Chem. 2006, 252, 90.

Keywords: Nanocatalyst, Coordination, Nanoparticles

MS.B2.P.265 The coordination Structure of Self-Assembled Multilayers of Polyoxometalate Nanoclusters Ali Ghariba,b M. Jahangir,a a Department of Chemistry, Islamic Azad University, Mashhad, Iran, [email protected], bAgricultural Researches and Services Center, Mashhad-IRAN. E-mail: aligharib5@ yahoo.com Using electrostatic layer-by-layer self-assembly (ELSA), the formation of multilayers with polyelectrolytes and nanoscopic polyoxometalate (POM) clusters of different sizes and charges is investigated. The ability of POMs to accept electrons under alteration of the optical properties can be used for the construction of functional electrooptical materials. [1] While the extinction coefficients of reduced POMs are comparable to those of organic dyes, the photochemical stability of reduced POMs is far superior to that of organic molecules. [2] Although the number of functional POM compounds is steadily increasing, progress in POM synthesis has not been paralleled by a concomitant development of POM-based functional materials and devices. The realization of POM-based materials will require new methods to combine, position, and orient the clusters in the device architecture. [3] POMs are unique model systems to study fundamental questions in multilayer assembly. Moreover, we can address questions concerning environmental effects on the function by investigating changes in the physicochemical properties of the immobilized POM clusters, including electrochemistry, fluorescence, and optical absorption. [4] To learn more about the assembly of these systems, we present a detailed investigation on multilayer assemblies with POM clusters of different sizes and charges (Figure 1) and discuss some of

Clusters Used in This Studya and (Bottom) Schematic Illustration of the ELSA Films Assembled with Negatively Charged Nanoscopic POM Clusters (Polygons) and Macromolecular Polyelectrolytesb. Abbreviations: Co-POM, [Co4(H2O)2P4W30O112]16-; Na-POM, [Na(H2O)P5W30O110]14-; Eu-POM, [Eu(H2O)P5W30O110]12-.The Eu- and Na-POMs are isostructural but differ in the total charge. b The packing density of the POMs, the film architecture, and the permeability of the multilayers are readily controlled through the assembly conditions. a

[1]a) M. Jones, J. Smith, Abbreviated Journal Name, 2012, 9, 9-13. b) Liu, S.; Kurth, D. G.; Mo¨hwald, H.; Volkmer, D. AdV. Mater. 2002, 14, 225. [2] Yamase, T. Chem. ReV. 1998, 98, 307. [3] Kurth, D. G.; Volkmer, D. In Polyoxometalate Chemistry; Pope, M. T. [4]Muller, A., Eds.; Kluwer: Dordrecht, 2001; pp 301-318.

Keywords: Polyoxometalate, Coordination, Nanostructure

MS.B2.P.266 Crystalline Lattices of the [V12B18O60H6]n- with Different Countercations P. Hermosilla-Ibáñez,a,b J. Costamagna,a A. Vega,b,c E. Le Fur,d,e M. T. Garland,f E.Spodine,b,g D. Venegas-Yazigi.a,b aFacultad de Química y Biología, Universidad de Santiago de Chile, USACH,(Chile), b CEDENNA,(Chile), cUniversidad Andres Bello, Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, (Chile),dENSCR, CNRS, UMR 6226, Rennes, (France), eUniversité Européenne de Bretagne, (France), fFacultad de Ciencias Físicas y Matemáticas. Universidad de Chile, (Chile), gFacultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, (Chile). E-mail: patricio. [email protected]; [email protected] In recent decades the polyoxometalates (POMs) have been of great scientific interest due to their rich variety of structural and chemical properties. A new family of POMs which has been recently explored are the vanadoborates. An interesting feature of these polyanions is that they can present different mixed valence states, i.e. different V4+/ V5+ ratios [1-2]. The negative charge of the [V12B18O60H6]n- cluster

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Active component nanoparticles (Preyssler heteropolyacids) can be stabilized or anchored to various substrate materials by use of a chemical template.

Poster Sessions depends on the number of VIV in the structure. The lattices in which these clusters crystallize, present several water molecules and their negative charge is compensated by cations, such as alkaline ions, protonated organic amines and coordination complexes, among others. In this work, we present the synthesis and structural characterization of five compounds, derived from the [V12B18O60H6]n- vanadoborate cluster (figure). The countercations present in the studied complexes are alkaline ions (K+, Cs+), hydronium ions and protonated amines. (1) K10(H3O)[V12B18O60H6]·8.5H2O (2) K8Cs2[V12B18O60H6]·10.42H2O (3) (NH4)7(H3O)(1,3-diapH2)[V12B18O60H6]·5H2O (4) K5(H3O)(1,3-diapH2)2[V12B18O60H6]·11.8H2O (5) K(H3O)(enH2)4[V12B18O60H6]·9.6H2O

Figure. Polyhedral representation of the cluster [V12B18O60H6]n-

of the high symmetry of these clusters, new theories were developed which, in some cases, provide important suggestions on the role of the electron transfer processes on their magnetic properties. In the present work we studied the clusters formed by Nd3+ and 3+ Ho , respectively, with paramolybdate,[Mo7O24]6-. Magnetic susceptibility measurements of sample were performed on polycrystalline samples on a SQUID magnetometer in DC and AC field. Magnetic results have shown that the exchange interaction in the Nd3+ sample are antiferromagnetic and in Ho3+ sample are diamagnetic. The characterization of the systems Ln3+-POM was accomplished by means of FTIR and UV-Vis spectroscopy, thermal analysis. The structure was confirmed by single crystal X-ray structural analysis (see Figure). The structure was solved by the direct method and refined by the full-matrix least squares method on F2 using SHELXTL 97 crystallographic software package. The magnetic characterization of the investigated systems was realized by correlating the data from both ordered and paramagnetic states, which allowed the calculation of magnetic moments and the contribution of each element to the total magnetization of the compound. In the FTIR spectra of the obtained compounds the shape of peaks in the range 600-1800 cm-1 is nearly identical to initial POMs except slight shifts of some peaks due to the effect of coordination. This fact indicates that the polyoxomolybdates in the two compounds retains the basic structure, which is in agreement with the result of single-crystal X-ray diffraction analysis.

Acknowledgements: Authors acknowledge Financiamiento Basal Program FB0807 and FONDECYT 1120004 for partial financial support. The authors also thank ECOS-CONICYT C08E02 International Project. This work was done under the LIA-MIF CNRS 836 Collaborative Program. PHI thanks MECESUP UCH 0601 Doctoral Scholarship and AT-24100222 CONICYT. Thanks are given to the Consejo Superior de Investigaciones Científicas (CSIC) of Spain for the award of a license for the use of the Cambridge Crystallographic Data Base (CSD). [1] I. Williams, M. Wu, H. Sung, T. Law, X. Zhang, in “Contemporary Boron Chemistry”RSC, London, 2000, 104-111. [2] K. Brown, P.E. Car, A. Vega, D. Venegas-Yazigi, V. Paredes-García, M.G. Vaz, R. Allao, J-Y. Pivan, E. Le Fur, E. Spodine, Inorg. Chim. Acta, 2011, 367, 21-28.

Keywords: polyoxovanadoborate, vanadium, crystal structure

MS.B2.P.267 Lanthanide Polyoxomolybdates: Synthesis, Structure and Magnetic Properties Ionel Humelnicu,a Sergiu Sova,b Doina Humelnicu,a Petre Badica,c Marilena Ferbinteanu,d aAl. I. Cuza University of Iassy, Iassy (Romania). bState University, Chisinau, (Moldova). bNational Institute of Materials Physics, Magurele (Romania). dUniversity of Bucharest, Bucharest (Romania). E-mail: [email protected] Polyoxometalates field combines classical areas of metal oxides and coordinative compounds. Polyoxometalates of lanthanides ions are currently under extensive investigations for both theoretical and practical points of view. Lanthanide ions and POMs form classes of materials with various potential applications in different domains: photochemistry, catalysis, material science, magnetism. Our interest is to investigate the new synthesis method for polyoxometalates and their magnetic properties. A relevant role of the polyoxometalates in determining the desired magnetic properties is to function as ligands toward other metal magnetic centers, incorporating them, too. In this way, magnetic clusters with different spin topologies are formed. Quantitative interpretation of magnetic properties of POMs remains a challenge because they sometimes have a structure too complex to be handled with existing theories. Taking advantage

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Keywords: lanthanide, polyoxomolibdates, magnetism

MS.B2.P.268 Suzuki and Heck C-C Cross-Coupling Catalyzed by Palladium Supported on Polyoxometalates Ibrahim Karumea, Henry Ssekaaloa, Emmanuel Tebandekea and Ola F.Wendtb, aDepartment of Chemistry, Makerere University(Uganda). b Centre of Analysis and Synthesis, Lund University (Sweden). E-mail: [email protected] Over the past three decades there has been increased effort to develop new catalytic systems for carbon-carbon coupling reactions. The interest in these reactions was enhanced by the need for more efficient methods of producing biaryl systems and new drugs based on natural products. In this work, palladium nanoparticles were stabilized in aqueous solution by polyoxometalates (POMs) and eventually supported on potassium or barium salts of the POMs. Characterization of the supported catalysts was achieved using inductively coupled plasma atomic emission spectroscopy and single crystal X-ray crystallography among other analytical techniques. The palladium supported catalysts were applied in the Suzuki and Heck C-C cross-coupling reactions. Under optimized conditions palladium catalyst supported on the barium salt of the POM (PdBaPOM) proved to be an excellent catalyst for the Suzuki C-C crosscoupling between phenylboronic acid and several aryl halides in the presence of a base co-catalyst. The progress of the reactions was followed using GC and GC-MS studies. In this work, the corresponding biaryls were produced in excellent yields and selectivity. For example,

Poster Sessions

Keywords: suzuki, heck, c-c coupling

MS.B2.P.269 Triphosphatoperoxotungstates - 31P NMR and Structural Study Yusuke Kunigita,a, b Masato Hashimoto,a aDepartment of Material Science and Chemistry, Faculty of Systems Engineering, Wakayama University, Wakayama (Japan). bFaculty of Bioscience, Nara Institute of Science and Technology, Ikoma, Nara (Japan). E-mail (MH): [email protected] Phosphorus is the most common heteroatom in the polyoxometallate chemistry mainly because of its low toxicity, stability, large ability of anion construction and possibility to obtain structural information from NMR. Monomeric orthophosphate is usually selected as the heteroatom group, and a great numbers of anions have been found out so far. However, investigations on oligophosphate-containing polyoxometallates are exclusively limited to diphosphate systems. In the course of the authors’ investigations on peroxometallates, the complex formation of a linear triphosphate (P3) with peroxotungstates was tested and isolation of the formed anions was attempted with a variety of counter cations. The anion formation reactions were examined by 31P and 183W NMR as a function of pH, cation, time, total concentrations of W and P3, and molar ratios of peroxide/W and W/P3. An example of 31P NMR is shown in Fig. 1. The triphosphate is characterised by two 2:1 or three 1:1:1 signals. The central phosphorus, a triplet in coordinationfree form, appears at higher field area, usually 81% of the Cu(II) ions in a solution of different metal ions at pH 5.09. This selectivity can be explained by the formation of three six-membered chelate rings upon metal complexation which are more selective for smaller metal ions. Competitive transport experiments (water/chloroform/water) were undertaken employing each ligand separately as the ionophore in the membrane (chloroform) phase. The pH of the source phase was 5.09 and that of the receiving phase 1.0. Sole transport selectivity for Cu(II) was observed. Even though a large concentration of Cu(II) was present in the membrane phase, no Cu(II) was present in the receiving phase, indicating that a pH of 1.0 is not the optimum pH for stripping into the receiving phase. Several crystal structures were obtained, not only to see how the metal ion coordinates, but also to see how the anion is kept in position. One such crystal structure depicting Cu(II) bound to Ligand 3 is shown below. Further crystal structures and pH isotherms of these ligands with several metal ions are currently being determined. This study illustrates that simple ditopic ligands can be used to selectively extract metal salts which provides an advantage over conventional ion exchange reagents which add components to the aqueous stream.

Poster Sessions

[1] S. G. Galbraith,P. A. Tasker, Supramolecular Chemistry, 2005, 17, 191-13. [2] International Labour Orgainisation, Encyclopaedia of Occupational Health and Safety, Vol III, 1998, 82. [3] J. Szymanowski, in Hydroxyoximes and Copper Hydrometallurgy, CRC Press, Boca Raton, FL, 1993, 62.

Keywords: ligands, extraction, copper(II)

MS.C1.P.306

In this work, a photocatalytic system to degrade BTEX-phenol was developed using mixed oxide (Ti/Al), obtained by calcined hydrotalcites-like compounds (layered double hydroxides) synthesized by sol-gel technique with ultrasound vs. microwave irradiation. The effect of synthesis parameters: pH, time and power ultrasound and microwave irradiation were studied. The optimization of the synthesis was performed by X-ray diffraction. We found that in these methods textural propertiescan be controlled such as porosity and specific surface area, these properties depend significantly on the preparation method, the irradiation time, power-frequency of irradiation and the type of interlayer component. The new materials have excellent morphological properties in comparison with the commercial TiO2. The solids were characterized by X-ray diffraction (DRX), nitrogen physisorption (BET), Infrared spectroscopy (FTIR) and scanning electron microscopy (SEM-EDS). The synthesized materials in calcined form were evaluated in the photodegradation of BTEX-phenol mixture, the results were compared with those obtained by the photodegradation with TiO2 (Aldrich) anatase phase. The photodegradation process of the mixture BTEXPhenol was optimized considering the ratio of catalyst/pollutant concentration and contact time. It was found that the best photocatalyst was a mixed oxide (Ti/Al) obtained from hydrotalcites-like compounds with x = 0.25 and treated with ultrasound irradiation; the degradation percentage was 88 % greater than the obtained with TiO2 (Aldrich) anatase phase at 200 minutes of contact.

Recently it was shown that powders prepared by the entrapment of nickel complexes with tetra-aza-macrocyclic ligands in sol-gel matrices can be used as electron exchange columns.1 However repeated use of the same column resulted in loss of the redox reagent by elution of the complex from the matrix. It was decided therefore to bind covalently redox active complexes to the surface of silica-gel particles. This was done by reacting (C2H5O)3Si-(CH2)3-NH2 with the silica-gel particles followed by the reaction with 1,4,7,10-tetraazadecane in the presence of Ni(ClO4)2. The product thus obtained was identified by EPR, NMR, CV and UV-vis spectra. The product was shown to act as a stable electron exchange column. Oxidation of the Ni(II) complex was performed by S2O82- and reduction by organic substrates. [1] Y. Lavi, A. Burg, E. Maimon, D. Meyerstein, Chemistry Eur. J., 17, 51875191, 2011.

Keywords: keyword-1, keyword-2, keyword-3

MS.C1.P.307 BTEX-Phenol Photodegradation by Mixed Oxides (Ti/Al) Obtained from Hydrotalcites Synthesized by Ultrasound Vs. Microwave Irradiation Silvia P. Paredesa, Miguel A. Valenzuelaa, Martha L. HernándezPichardoa, ElimAlbitera. aNational Polytechnic Institute, ESIQIE, Catalysis and Materials Laboratory, Ed. Z-6 1er piso UPALM, Zacatenco, 07738, D.F. (México).E-mail:[email protected]

Keywords: photodegradation, BTEX- phenol

hydrotalcite-like

compounds,

MS.C1.P.309 Metal Ion Separation-A View to the Future Zenixole R. Tshentu, Adeleye I. Okewole, Nomampondo P. Magwa, Avela Majavu, Omolola Fayemi, Wesley Feldmann, Sam Chigome, Edith Antunes, Nelson Torto, Gareth M. Watkins. Department of Chemistry, Rhodes University, P.O. Box 94, Grahamstown 6140, South Africa. E-mail: [email protected] The use of solvent extraction (SX) in the separation of base metals continues to dominate the field of metallurgy and commercial plants based on this process account for more than 50% of base metal production [1,2]. Current industrial extractants, however, are based on oxygen donors such as the famous LIX and Cynex reagents [1,2], and a question of selectivity has not been addressed in full considering that hard ions have a greater affinity for these extractants. This necessitates for an initial precipitation step to remove Fe(III) at pH 3, followed by the extraction of the metals at pH 4-6 [2]. This study proposes the use of aromatic nitrogen donor extractants as reagents for the separation of metals in highly acidic sulfate solutions. The results of this investigation proved that the separation of Ni(II) from Co(II) using 1-octyl-2,2’-pyridylimidazole (OPIM)

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Design of Electron Exchange Columns Dan Meyersteina,b Smadar Attiaac, Alexander Shamesd, Eric Maimonac, Israel Zilbermannac, aChemistry Dept., Ben-Gurion University of the Negev, Beer-Sheva, Israel. bBiological Chemistry Dept., Ariel University Center of Samaria, Ariel, Israel. cNuclear Research Centre Negev, Beer-Sheva, Israel. dPhysics Dept., Ben-Gurion University of the Negev, Beer-Sheva, Israel.

Poster Sessions and dinonylnaphthalene sulphonic acid (DNNSA) in 2-octanol/ shellsol2325 can be achieved with ∆pH½ ~ 1.6, and the rejection of the hard ions such as Fe3+, Mn2+, Mg2+ and Ca2+ in highly acidic sulfate/chloride medium was also successful (see the figure below). A scrubbing step to remove the co-extractants and a selective stripping step have also been adopted to recover high purity nickel from a loaded organic (L.O.) phase [3]. Recently, these studies have been extended to include the development of chelating solid sorbents (Merrifield beads and nanofibers) for the separation of base metal ions. The paper will also share some of the advances in the use of microparticles and nanofiber platforms fabricated through the electrospinning approach [4] and their functionalization with ammonium and quarternary ammonium groups for the separation of PGM chloro species by ion exchange (IX) methods. This new class of sorbents could revolutionalize the separation technology of these metals.

It is proposed that this increased strength is due to the stability inferred by the formation of a six membered proton chelate ring between the amido oxygen and the ammonium proton. We have also observed unusual selectivities between chlorometallates such as ZnCl42- over FeCl4-, which appear to be due to different goodnessesof-fit of both N-H and C-H groups for the centres of negative charge on the chlorometallate. An example is provided by the pyridinomalonamide derivative shown below which was designed to be sterically hindered about its basic nitrogen atom to prevent innersphere complex formation.[3] It forms nine short H…Cl contacts when addressing the outer coordination sphere of ZnCl42-. These reagents have also been altered to examine the importance of the order of the atoms that constitute the proton-chelate ring.

[1] K. J. Bell, et. al. Angewandte Chemie, International Edition, 2008, 47, 9, 1745-1748, [2] R. J. Ellis et. al. Chem. Eur. J., 2012, in press, [3] R. J. Ellis, et. al. Chemical Communications, 2009, 5, 583-585.

Keywords: chlorometallate, anion, extraction [1] K.C. Sole, A.M. Feather and P.M. Cole, Hydrometallurgy, 2005, 78, 52-78. [2] B.R. Reddy, S.V. Rao, K.H. Park, Min. Eng., 2009, 22, 500-505. [3] A.I. Okewole, N.P. Magwa and Z.R. Tshentu. Hydrometallurgy, DOI: 10.1016/j. hydromet.2012.04.002. [4] A. Greiner, J. H. Wendorff, Angew. Chem. Int. Ed, 2007, 46, 5670-5703.

Keywords: base metals, platinum group metals, separation

MS.C1.P.310 Chlorometallate Extraction via Outer-Sphere Complexation Jennifer R. Turkington, Philip J. Bailey, Ross J. Ellis, Peter A. Tasker and Violina Cocalia,b aSchool of Chemistry,University of Edinburgh, EH9 3JJ (UK). bCytec Industries Inc., W. Main St, Stamford, CT 0690, (USA). Email: [email protected] a

a

a

a

In most cases the efficient transfer of chlorometallate anions, MClxy-, to a water-immiscible solvent requires an anion exchanger to show selectivity over chloride ions which are present in high concentration in aqueous feeds. Selectivity of extraction between different chlorometallates is very dependent on their relative hydration energies. We have recently investigated the effect of introducing hydrogen-bonding functionalities into anion-exchange extractants to address the outer coordination spheres of chlorometallate complexes to tune selectivity.[1],[2] The new reagents have been shown to be stronger extractants than simple trialkylamines in pH-dependent extractions, such as: yLorg + yH+ +MClxy- ⇌ [(LH)yMClx](org)

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MS.C1.P.311 Solvent Extraction of Platinum by Formation of Outer-Sphere Complexes Matthew Wilson,a Ross Gordon,b Richard Grant,b Jason Love,a Peter Tasker.a aEaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, (UK). bJohnson Matthey Technology Centre, Sonning Common (UK). E-mail: [email protected] Amide-functionalised amines have been shown to be strong extractants for both precious and base metals from acidic chloride solutions with potential application in extractive metallurgy. [1], [2] Extraction of a chlorometallate, MClxy-, into a water-immiscible liquid requires the formation of a neutral outer sphere-complex using cationic ligands. Metal uptake is conveniently accomplished by generating a cationic form of the extractant by protonation in an equilibrium which is pH dependent: yL(org) + yH+ + MClxy- ⇌ [(LH)yMClx](org) Recovery of the metal from the loaded organic solution can be achieved stripping with aqueous base: [(LH)yMClx](org) + yOH- ⇌ MClxy- + yL(org) + yH2O

This paper considers the mode of action of extractants for Pt(IV), work stimulated by the growth in the global demand for PGM’s which requires the development of more efficient recovery processes. On protonation the new amido/amine reagents present an array of N-H and C-H hydrogen bond donors to address the outer coordination spheres of chlorometallate anions, showing greater strength as PtCl62-

Poster Sessions extractants and higher selectivity over chloride than trialkylammonium ions which are models for the commercial Alamines.® The X-ray structure determination of [(LH)2PtCl6] confirms the formation of such an outer sphere complex with L = N-benzyl-3-(benzyl(phenyl)amino)N-phenylpropanamide. Scheme 1. Reaction pathway for HMF hydrogenation [1] J. N. Chheda, G. W. Huber, J. A. Dumesic, Angew. Chem. Int. Ed. 2007, 46, 7164. [2] A.A. Rosatella, S.P. Simeonov, R.F.M. Frade, C.A. Afonso, Green Chem., 2011, 13, 754. [3] B. L. Conley, M. K. Pennington-Boggio, E. Boz, T. J. Williams, Chem. Rev., 2010, 110, 2294; L.Busetto, D. Fabbri, R. Mazzoni, M. Salmi, C. Torri, V. Zanotti, Fuel, 2011, 90, 1197.

Keywords: 5-hydroxymethylfurfural, hydrogenation, Shvo’s catalyst

Keywords: solvent extraction, outer sphere, platinum

MS.C1.P.312 Hydroxycyclopentadienyl Ruthenium Hydride Catalyzed Homogeneous Hydrogenation: the Selective Reduction of Biomass Derived 5-Hydroxymethylfurfural Valerio Zanotti,a Rita Mazzoni,a Mattia Vaccari,a Thomas Pasini,b Stefania Albonetti,b Angelo Vaccari,b Fabrizio Cavani,b a Dip. di Chimica Fisica e Inorganica, viale del Risorgimento 4, 40136 Bologna, Italy. bDip. di Chimica Industriale e dei Materiali, viale del Risorgimento 4, 40136 Bologna, Italy E-mail: [email protected] Dehydration of glucose and/or fructose leads to the formation of 5-hydroxymethyl-2-furfural (HMF) which is a key precursor for applications in pharmaceutical and polymer industry [1]. Selective reduction of the formyl group of HMF leads to formation of 2,5-bis(hydroxymethyl)furan (BHMF), an important chemical building block for the production of polymers and polyurethane foams [2]. HMF reduction has been developed employing sodium borohydride, formalin and aq. NaOH, and several heterogeneous catalysts based on transition metals. In the latter cases, high temperature (140–200 °C) and hydrogen pressures (70–75 bar) were required. In order to perform the reaction under milder conditions our attention has been recently devoted to homogeneous hydrogenation mediated by ruthenium complexes. In particular Shvo catalyst (1) is a very good candidate for the selective reduction of aldehydes by means of homogeneous hydrogenation since it hydrogenates polar double bonds leaving aromatic rings unaltered [3]. The precursor 1 is in equilibrium with the hydroxycyclopentadienyl ruthenium hydride active specie [Ph4(η5-C4COH)]Ru(CO)2H [3], which works with a bifunctional metal-ligand mechanism leading to a quantitative yield of BHMF, with a complete selectivity and under mild conditions (P(H2) = 10 bar, T = 90 °C, HMF/1 molar ratio = 1000). The dependence of the hydrogenation on H2 pressure, total ruthenium concentration, temperature and time were investigated. Stability of the Shvo catalyst under operative conditions was evaluated by re-using it in consecutive runs. Reusability tests show that the catalyst is significantly stable in the reaction conditions and can be reused without any loss of activity.

MS.C2.P.313 Synthesis of Complexes of Ru (II) and their Catalytic Activity in Hydrogenation Of Imines Sergio Moya,a Matías Vidal,a, Rebeca Sartoria Pedro Aguirre,b Gabriel Abarca,b Camila Negrete.b Hubert Le Bozec,c Verónique Guerchais,c a Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago (Chile). bFacultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago,(Chile). cSciences Chimiques de Rennes, Université de Rennes 1, Rennes (France). E-mail: sergio. [email protected] A large number of metal catalysts have attracted considerable attention in recent decades because of their utility in the hydrogen transfer reaction [1]. A variety of metal complexes have been used extensively in catalytic reactions of hydrogen transfer, finding quite good activities in organic transformations [2]. In the present work, we report the synthesis of a series of compounds of Ru (II) containing polypyridine ligands. In addition, preliminary studies of the catalytic activity in hydrogenation of imines using 2-propanol as the source of hydrogen are reported. The compounds were characterized by IR spectroscopy and 1H and 31P-NMR. The results give support to the proposed formulation. The metal complexes derived from the precursor [RuCl2 (η6-p-cymene]2 and [Ru(CO)2Cl2]n containing polypyridine ligands derived from bipyridine. The new catalysts showed excellent catalytic activities for the hydrogenation of imines derived from N-benzylideneaniline. Conversions above 95% at 16 hours of reaction were obtained. Studies to improve the results are currently underway.

Figure 1 Synthesis of [RuCl(η6-p-cimeno)BpyFcn]PF6 complex [1] J. E. Bäckvall, J. Organomet. Chem. 2002, 652, 105. [2] J. R. Miecznikowski, R. H. Crabtree, Organometallics, 2004, 23, 629.

Keywords: catálisis, complexes of Ru (II), hydrogenation of imines Acknoeledments. We thank to Fondecyt-Chile (Grants 1120685 and 1120149) and LIA (Chile-France)

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[1] R. J. Warr, A. N. Westra, K. J. Bell, J. Chartres, R. Ellis, C. Tong, T. G. Simmance, A. Gadzhieva, A. J. Blake, P. A. Tasker, M. Schröder, Chem. Eur. J, 2009, 15, 4836 - 4850. [2] R. J. Ellis, J. Chartres, P. A. Tasker, K. C. Sole, Solvent Extraction and Ion Exchange, 2011, 25, 657-672.

homogeneous

Poster Sessions MS.C2.P.314

MS.C2.P.315

Palladium (II) Catalysts with Phosphorous-Nitrogen Ligands for the Reaction of Hydroesterification of Olefins

Catalytic Abilities of Novel Molybdenum-Cupper Clusters with Scorpionate Ligands Haruo Akashia, Ryouichi Yoshidaa, and Takashi Shibahara,b aResearch Institute for Natural Sciences, Okayama University of Science, Okayama, (Japan) bDepartment of Chemistry, Okayama University of Science, Okayama, (Japan). E-mail: [email protected]

P. Aguirrea*,G. Abarcaa, C. Negrete-Vergaraa, S.A. Moyab, M. Vidal,b aUniversidad de Chile, Facultad de Ciencias Químicas y Farmacéuticas, Departamento de Química Inorgánica y Analítica, Santiago (Chile). bUniversidad de Santiago de Chile, Facultad de Química y Biología, Departamento de Química de los Materiales, Santiago (Chile). E-mail: *[email protected] The olefins hydroesterification reaction is catalyzed mainly by palladium. Complexes of these metal containing ligands such as phosphine and phosphorous-nitrogen allow the formation of esters in high yield[1]. This reaction has been applied as a method of synthesis in many industrial processes; one of the most important being the obtention of methyl methacrylate by carbonylation of alkynes using nitrogen-phosphorus ligands. This work describes the synthesis and characterization of a new generation of complexes containing phosphorous-nitrogen ligands and their study as catalysts in the reaction of hydroesterification of olefins. The ligands and the catalysts were prepared by methods reported by us in the literature [2] and were characterized by the usual techniques in coordination chemistry such as NMR, elemental analysis and others. The catalytic reactions were carried out in high pressure reactors using variable pressures and temperatures in order to optimize the reaction conditions. The results show that the prepared catalysts allow conversions between 60-92% at pressures under 50 bar and at 75 º C. It was observed that this type of ligands directs the reaction to the formation of mainly a branched ester with a 98 ratio, with high chemoselectivity. The reaction requires the addition of low amounts of triphenylphosphine which allows obtaining a catalytic system with high stability under the reaction conditions. Scheme 1. General scheme for hydroxy and alkoxycarbonylation of olefins.

Table 1. Catalytic results for the hydroesterification reaction applied Pd (II) catalysts. Catalyst Pd-1 Pd-2 Pd-3 Pd-4 Pd-5

Conversion 52 56 76 15 90

Chemoselectivity >98 >99 100 100 100

Regioselectivity 95 95 >99 >99 >98

In 1986, we reported the first example of the metal incorporation reaction of Mo3S4 aqua cluster, [Mo3S4(H2O)9]4+ (1) [1]. Then, we have focused on the reactivity of lone pair electrons of mS atoms in 1 and its ability to incorporate heterometals to afford a variety of mixed-metal cubane-type sulfide clusters containing Mo3MS4 cores (M=Fe, Co, Ni, Cu, and so on.) [2]. We have recently reported that the reaction of [Mo3S4(H2O)9]4+ (1) with hindered hydrotris(methimazolyl)borate (= TmMe) ligands afforded [Mo3S4(TmMe)3]Cl (2) [3]. Complex 2 functions as a metal-complex ligand for preparing novel mixed-metal complexes in non-aqueous solvents. We have also reported novel molybdenum-copper compounds, [Mo3CuClS4(TmMe)3]Cl (3) and [{Mo3CuClS4(TmMe)2}2O2Cl]Cl (4) [3]. These compounds function as a catalyst for intramolecular cyclization of 4 - pentynoic acid. In this report, we succeeded in the development of a new compound [{Mo3CuClS4(Tp)2}2(pz)2O] (5) successfully isolated from the reaction of [{Mo3S4(Tp)2}2(pz)2O] (6) [4] with copper(I) chloride. We tested a catalytic system containing 5 and triethylammine in the intramolecular cyclization reaction of 4-pentynoic acid. The ratio of 4-pentynonic acid to catalyst is hundred thousand and the temperature is 40 degrees Celsius, and 70% of 4-pentynoic acid was converted. The TON reached 70000 after 24 h. Details will be discussed.

[1] T. Shibahara, H. Akashi, H. Kuroya, J. Am. Chem. Soc. 1986, 108, 1342-1343. [2] H. Akashi, K. Isobe, and T. Shibahara, Inorg. Chem. 2005, 44, 3494-3498. [3] H. Akashi, R. Yoshida, T. Shibahara, Abstract of XXIIIth International conference on coordination and bioinorganic chemistry 2011, C-2, (Slovakia). [4] F. A. Cotton, R. Llusar, W. Schwotzer, Inorg. Chim. Acta 1989, 155, 231-236.

Reaction conditions: C6H5Me/MeOH (15/5 mL), Pd/sust 1/600, Pd/TsOH 1/10, Pd/PPh3 1/1, 75°C, 50 bar CO, t= 9h.

Keywords: mixed-metal cluster, metal-complex ligand, catalyst

The proposed catalysts of the type [Pd(PN)(PPh3)Cl] Cl shown to be active catalysts in the reaction of hydroesterification of olefins. For these catalysts the reaction is favored by the presence of triphenylphosphine and phosphorus-nitrogen ligand.

MS.C2.P.316

[1] C. Zuñiga, S.A. Moya, P. Aguirre. Catal Letters, 2009, 130, 373. [2] P. Aguirre, C. Lagos, S. A. Moya, C. Zuñiga, C. Vera-Oyarce, J. C. Bayón. E. Sola. Dalton Trans. 2007, 46, 5419-5426. Keywords: Hydroesterification, Pd catalysts, methoxycarbonylation olefin Acknoeledments. We thank to Fondecyt-Chile (Grants 1120149 and 1120685 ) and LIA (Chile-France).

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Double H Transfers as Essential Steps in Homogeneous Hydrogenations and Transfer Hydrogenations Heinz Berke1, Anne Landwehr1, Subrata Chakraborty1, Balz Dudle1, Thomas Fox1, Olivier Blacque,1 1Anorganisch-chemisches Institut, Universität Zürich, Winterthurer Strasse 190, 8057 Zürich, (Switzerland). E-Mail: [email protected]. Double H transfers involve exchange of chemically bound two hydrogen atoms between a pair of a hydrogen donor and a hydrogen acceptor appearing in reaction courses of transition metal induced homogeneous hydrogenations, dehydrogenations and transfer hydrogenations either as concerted (see below) or stepwise steps with

Poster Sessions subsequent H transfers [1]. Polar “bifunctional” H atom transfers with formal transfers of H- and H+ or as H(d-) and H(d+) possess lower activation barriers.

Ligand–metal bifunctional catalysis is an efficient method for hydrogenations of unsaturated organic compounds in Shvo type hydrogenations [2] or Noyori type transfer hydrogenations [3]. We attempted a new approach with isoelectronic replacement of the hydridic H-Ru-CO moiety of Shvo systems with the H-Re-NO unit resulting in bifunctional Re(NO)(L)(H)(C5H4OH) complexes (L = PR3). Such complexes were prepared and the catalytic performance was probed in transfer hydrogenations of ketones and imines using isopropanol as a hydrogen donor (TOFs for acetophenone up to 1164 h-1 and for 1,2-diphenyl imine up to 79 h-1). Mechanistically these catalyses were feasible on the basis of the existence of hydrogen donor and hydrogen acceptor forms [4]. Very efficient hydrogenations of imines of the Noyori type could be achieved with W and Mo centers bearing PNP ligand systems showing TOFs of up to almost 3000 h-1. The crucial steps are H2 uptake followed by secondary coordination sphere H transfers [5].

to first oligomerize ethylene to 1-butene and 1-hexene; followed by Friedel-Crafts alkylation of the toluene by the olefins to mainly butyltoluene derivatives [2].In the current report we investigated the use of ferrocenyl-supported pyrazolyl nickel and palladium complexes as catalysts for the oligomerization of ethylene and higher olefins; using EtAlCl2 and toluene as solvent. We observed the oliogmerization of ethylene to 1-butene and 1-hexene and the Friedel-Crafts alkylation of toluene not only by 1-butene, but also of toluene by ethylene to ethyltoluene derivatives (Scheme 1). Although Lewis acids by themselves are able to catalyze the Friedel-Crafts alkylation of aromatic compounds by olefins, the facile manner in which our pyrazolyl nickel and palladium complexes are able to catalyze the alkylation of toluene by ethylene and 1-butene that the aluminium co-catalyst and the pyrazolyl nickel and palladium complexes act in tandem to catalyze these reactions. This presentation will discuss the synthesis of these pyrazolyl nickel and palladium complexes as well as their catalysis in these transformation reactions.

Scheme 1: Ethylene oligomerization and Friedel-Crafts alkylation of toluene. [1] S.O. Ojwach, J. Darkwa, Inorg. Chim. Acta, 2010, 363, 1947-1964. [2] S.O. Ojwach, I.A. Guzei, L.L. Benade, S.F. Mapolie, J. Darkwa, Organometallics. 2009, 28, 2127-2133.

Keywords: Ferrocenyl-pyrazolyl, nickel and palladium, olelfin transformation catalysts

[1] H. Berke, ChemPhysChem, 2010, 11, 1837. [2] B. L. Conley, M. K. Pennington-Boggio, E. Boz, T.J. Williams, Chem. Rev. 2010, 110, 2294. [3] R. Noyori, S. Hashiguchi, Acc. Chem. Res. 1997, 30, 97. [4] A. Landwehr, B. Dudle, T. Fox, O. Blacque, H. Berke, Chem. Eur. J. 2012, doi: 10.1002/ chem.20110. [5] S. Chakraborty, T. Fox, O. Blacque, H. Berke, 2012 to be submitted.

Keywords: Hydrogenation, Transfer hydrogenation, Ketone, Imine

MS.C2.P.317 Ferrocenyl-Pyrazolyl Nickel and Palladium Olefin Oligomerization and Polymerization Catalysts James Darkwa, Arnoux van der Westhuisen, Department of Chemistry, University of Johannesburg, Johannesburg (South Africa). E-mail: [email protected] Pyrazolyl-donor complexes have recently received a lot of attention as catalysts in a number of olefin transformation reactions [1]. In particular their nickel complexes have been found to catalyze the oligomerization of ethylene to butene, hexene and octene and have been reported by several research groups. However, we have observed that when the co-catalyst is EtAlCl2 and toluene is used as a solvent for the catalysis, pyrazolyl nickel complexes are able

MS.C2.P.318 Model Iridium Phosphine Based Complexes for use in Olefin Hydroformylation Ilana Engelbrecht, Andreas Roodt, Hendrik G. Visser, Department of Chemistry, University of the Free State, Bloemfontein, South Africa. E-mail: [email protected] The functionalization of olefins from petroleum sources to aldehydes through the process of Hydroformylation and is of great industrial importance. High selectivity for the desired isomer of the aldehyde can be kinetically manipulated by variation of the ligands and process conditions [1]. In rhodium systems, it is known that the presence of phosphine ligands give way to more active, highly selective catalysts reacting under milder reaction conditions [2]. Investigations as to the synthesis and evaluation of the solid state characteristics of the catalysts are very important, therefore in order to negate the complications frequently experienced with isolating Rh(I) and Rh(III) catalyst compounds, iridium complexes, with similar ligand sets, are used as model complexes as they tend to behave in the same way and are isolated more readily than the rhodium analogues. The coordination of various diphosphinoamine (PNP) ligands to different metal centres (Rh/Ir/Pt) (Figure 1) [3],[4] combined with structural and mechanistic studies are investigated to determine the importance of electronic factors and steric crowding from the phosphine based ligands for manipulating the reactivity and selectivity of the catalyst [5].

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Efficient hydrogenation catalyses could be developed with middle transition metals using the concept of bifunctional H transfers.

Poster Sessions 2011, 30, 6506-6509. [4] K. Fukumoto, A. Sakai, H. Nakazawa, Chem. Commun., 2012, 48, 3809-3811.

Keywords: desulfurization, thioamide, iron carbene complex

MS.C2.P.320 (a) (b) Figure 1: Crystal structures of (a) N,N-bis(diphenylphos-phanyl) cyclopentanamine and (b) bis[N,N-bis(diphenylphos-phanyl)cyclohexylaminek2P,P’]platinum(II) bis(hexafluorido-phosphate). [1] P.W.N.M. Van Leeuwen, Homogeneous Catalysis: Understanding the Art, 2004, Dordrecht: Kluwer Academic Publishers. [2] J.A. Osborn, G. Wilkinson, J.F. Young, Chem. Commun., 1965, 17. [3] I. Engelbrecht, H.G. Visser, A. Roodt, Acta Cryst., 2010, E66, o3322-o3323. [4] I. Engelbrecht, H.G. Visser, A. Roodt, Acta Cryst., 2010, E66, m994-m995. [5] A. Roodt, G. J. J. Steyn, Journal of Organomet. Chem., 1997, 536-537, 197-205.

Keywords: hydroformylation, iridium, phosphine

MS.C2.P.319 Desulfurization of Thioamide with Hydrosilane Catalysed by an Iron Complex Kozo Fukumotoa Akane Sakaib Hiroshi Nakazawa,b aKobe City College of Technology, Kobe (Japan). bDepartment of Chemistry, Graduate School of Science, Osaka City University, Osaka (Japan). E-mail: [email protected] Deoxygenation of amides including formamide with hydrosilane catalyzed by a transition metal complex to give amine and disiloxane has attracted considerable attention [1]. As iron is one of the best candidates as precious metal surrogates because of its price, abundance, and environmental compatibility, several such deoxygenation reactions catalyzed by iron complexes have been reported [2]. Quite recently, the sulfur version of deoxygenation of amides, that is, desulfurization of thioamides has been reported by Pannell (using Mo complex) [3] and by us (using Fe complex) [4]. We here report the reaction shown in eq 1 and the isolation and characterization of one of the intermediates in the catalytic cycle.

Carboxylate Based Manganese Complexes with Functional Relevance to Photosystem II Ching Ruey Raymond Gan,a Zhaolin Liu,b Shiqiang Bai,b Kian Soo Ong,b Tzi Sum Andy Hor,bc* aNUS Graduate School for Integrative Sciences and Engineering (NGS), Center for Life Sciences (CeLS), #05-01, 28 Medical Drive Singapore 117456, Singapore bInstitute of Materials Research and Engineering, Agency for Science, Technology and Research, 3 Research Link, S117602. Singapore. cDepartment of Chemistry, National University of Singapore, 3 Science Drive 3, S117543. E-mail: [email protected] Central to the Kok cycle of all oxygen evolving photoautotrophs harbours an inorganic core, Mn4CaOx coordinated within an embracing environment of carboxylic group in amino acids such as histidine, glutamic acid, aspartic acid and alanine.[1] The Mn4CaOx core denoted as the Water Oxidizing Complex (WOC) is the key to catalyzing one of the most energetically demanding reaction ever known (ΔH° = 572 kJ/mol);[2] in which the byproduct O2 fuels an amazing array of life form on earth: 2H2O à O2 + 4H+ +4e- [E°(pH =7): 0.815 V vs NHE] The photosynthetic WOC inspired a wide variety of artificial mimetrics ranging from molecular catalysts based on transistion metals such as Mn,[3] Ru,[4] Ir[5] to heterogenous cobalt catalyst constructed on electrochemical devices.[6] Our group has developed expertise on hematite nanorods for solar water oxidation[7] and explored several heterometallic manganese systems[8] towards artificial photosynthesis. Intrigued by the affinity of carboxylic acids towards the natural Mn4CaOx core, we began a systematic investigation on carboxylate coordinated manganese complexes and their influence on catalytic water oxidation. A series of dinuclear and trinuclear manganese complexes synthesized and isolated from carboxylate ligands were found to oxidize water using cerium ammonium nitrate (CAN) to varying degree. Under similar mole ratio of catalyst: oxidant = 1: 78, the trinuclear Mn complex 1 generated 17.5μmol of O2 with a TON of 15; much more than mono/ dinuclear Mn complexes (2 to 5) of various electronic configuration in figure 1. In short, numerical superiority followed by proximity of adjacent Mn centers and holds the key to successful utilization of dioxygen coupling mechanism approach[9] in PSII.

A photo irradiation of a solution containing THF (0.43 mL), CpFe(CO)2Me (1) (0.0531 mmol) (Cp = η5-C5H5), Me2NC(S)H (0.531 mmol) and Et3SiH (2.66 mmol) at 5 °C for 24 h generated (Et3Si)2S and NMe3, showing that 1 is a catalyst precursor. Similar desulfurization reactions were observed not only for thioformamide but also for thioamides. We also found that an iron carbene complex shown in Fig. 1 is one of the intermediates in the catalytic cycle. The structure of the SiPh3 derivative was determined by X-ray diffraction analysis. [1] D. Addis, S. Das. K. Junge, M. Beller, Angew. Chem. Int. Ed., 2011, 50, 6004-6011. [2] a) L. I. Kopylova, N. D. Ivanova, M. G. Voronkov, Zhur. Obshch. Khim., 1985, 55, 1649; b) S. Zhou, K. Junge, D. Adis, S. Das, M. Beller, Angew. Chem. Int. Ed., 2009, 48, 9507-9510; c) H. K. Sharma, K. H. Pannell, Angew. Chem. Int. Ed., 2009, 48, 7052-7054; d) M. Itazaki, K. Ueda, K. Kamata H. Nakazawa, Angew. Chem. Int. Ed., 2009, 48, 3313-3316; ibid, 48, 6938. [3] A.U. Renzo, K. S. Hemant, J. M.-M. Alejandro, K. H. Pannell, Organometallics,

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Figure 1: Oxygen output of complexes 1 to 5.

Poster Sessions

Keywords: water oxidation, manganese complexes, artificial photosynthesis

MS.C2.P.321 Recyclable Silica Supported Palladium Catalyst for Suzuki-Miyaura Cross-Coupling Reaction in Water Shanmugham Ganesamoorthy,a,b Kandasamy Shanmugasundram,b Govindasamy Manickam,b Manoharan Muthu Tamizh,a Ramasamy Karvembu,a aDepartment of Chemistry, National Institute of Technology, Tiruchirappalli 620015, India, bSynthetic Chemistry Unit, Syngene International Ltd., Biocon Park, Bangalore, 560099, India. E-mail: [email protected] The synthesis of biaryl systems and biheteroaryl systems by transition metal catalyzed cross coupling reactions are most attractive method in organic transformations. The recyclable palladium catalyst supported on silica is found to be very effective for SMC (SuzukiMiyaura coupling) reaction [1]. The Pd-loading of silica supported catalyst was determined by inductively coupled plasma (ICP-MS), SEM-EDX and XRS techniques. The surface area of silica supported catalyst was determined by BET and further characterized by solid state NMR and FT-IR spectroscopy. The catalyst stability against leaching of the active species into the reaction medium, and recycling capabilities are tested. The catalytic activity is optimized with different mole ratio, solvents and temperatures using 4-bromoacetophenone as model system. The scope of the reaction is extended to various types of aryl halides and heteroaryl halides. The use of recyclable Pd catalyst and water as a solvent under mild condition makes the reaction most interesting from both an economic and environmental point of view.

(France). bLaboratoire Charles Friedel, Chimie Paristech, Paris (France). cLPCNO, University Paul Sabatier, Toulouse (France). E-mail: [email protected] Commodity polymers such as polymethylmethacrylate or polydienes are ubiquitous in everyday life. On the other hand, biodegradable polymers such as aliphatic polyesters are attracting an ever growing attention, as potential answers to key environmental issues. They can be accessed by lactone ring-opening polymerization using rare-earth metal initiators. The polymers mechanical properties are chiefly governed by their microstructure, which in turn can be controlled through catalyst design, using ligands derived from multistep synthesis.[1] A simple way to produce stereoselective catalysts without time-consuming synthetic procedures is therefore of considerable interest. This problem can be efficiently tackled by use of well-defined supported catalytic systems based on rare-earth metal species.[2] Indeed, in sharp contrast to their homoleptic molecular counterparts, immobilized derivatives provide polymers with high degree of stereocontrol.[3] This has been demonstrated for several monomers (methylmethacrylate, isoprene, styrene, b-butyrolactone). We will show that this is linked to the grafting chemistry, by determining structure-selectivity relationships: a precise control over the surface species structure is of prime importance. Furthermore, understanding of this beneficial “surface effect” has been addressed through DFT calculations, which clearly demonstrate the impact of the silica surface on successive stereoselective monomer enchainments.[4]

[1] C. M. Thomas, Chem. Soc. Rev. 2010, 39, 165. [2] a) R. M. Gauvin, A. Mortreux, Chem. Commun. 2005, 1146, b) R. M. Gauvin, L. Delevoye, R. Ali Hassan, J. Keldenich, A. Mortreux, Inorg. Chem. 2007, 46, 1062. [3] a) N. Ajellal, G. Durieux, L. Delevoye, G. Tricot, C. Dujardin, C. M. Thomas, R. M. Gauvin, Chem. Commun. 2010, 46, 1032, b) M. Terrier, E. Brulé, M. J. Vitorino, N. Ajellal, C. Robert, R. M. Gauvin, C. M. Thomas, Macromol. Rapid Comm. 2011, 32, 215. [4]. I. Del Rosas, M. Tschan, R. M. Gauvin, L. Maron, C. M. Thomas. Polym. Chem. DOI: 10.1039/C2PY00472K.

Keywords: supported catalysis, rare-earth metals, polymerization

Scheme 1 Silica supported palladium catalyzed Suzuki-Miyaura cross coupling [1] S. Ogo, Y. Takebe, K. Uehara, T. Yamazaki, H. Nakai, Y. Watanabe, S. Fukuzumi, Organometallics, 2006, 25, 331-338.

Keywords: Suzuki reaction, silica support, catalyst recycling

MS.C2.P.322 Heterogenizing Rare-Earth Catalysts for Stereoselective Polymerizations R. M. Gauvin,a M. Tschan,b C. M. Thomas,b I. Del Rosal,c L. Maron,c L. Delevoyea. aUCCS, University of Lille-Nord-de-France, Lille

MS.C2.P.323 Palladium-Catalysed Direct Arylation of Organometallic Luminophores V. Guerchais,a M. Zaarour,a K. Beydoun,a J. Boixel,a J. A. G. Williams,b H. Doucet,a aInstitut des Sciences Chimiques de Rennes, UMR 6226 CNRSUniversité de Rennes 1 35042 Rennes Cedex, France. bDepartment of Chemistry, Durham University, South Road, Durham, UK DH1 3LE, United Kingdom. E-mail: [email protected] Catalytic C-H bond functionalisation, generally used for the synthesis of fine chemicals [1], has been applied to the organometallic luminophores and photochromic systems. Cyclometallated Ir(III) complexes of (hetero)arylpyridines are strongly phosphorescent at room temperature and chemical

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[1] J. Dasgupta, R. T. van. Willigen and G.C. Dismukes, Phys. Chem. Chem. Phys, 2004, 6, 4793-4802. [2] G.C. Dismukes, R. Brimblecombe, G. A.N. Felton, R. S. Pryadun, J. E. Sheats, L. Spiccia and G. F. Swiegers, Acc. Chem. Res, 2009, 42, 1935-1943. [3] J. Limburg, J. S. Vrettos, L. M. Liable-Sands, A. L. Rheingold, R. H. Crabtree and G. W. Budvig, Science, 1999, 283, 15241527. [4] L. Duan, A. Fischer, Y. Xu and L. Sun, J. Am. Chem. Soc, 2009, 131, 10397-10399. [5] A. Savini, G. Bellachioma, G. Ciancaleoni, C. Zuccaccia, D. Zuccaccia and A. Macchioni, Chem. Comm, 2010, 46, 9218-9219. [6] Y. Surendranath, M. Dinca, D.G. Nocera, J. Am. Chem. Soc, 2009, 131, 26152620. [7] Y. R. Hong, Z. Liu, S. F. B. S. A. Al-Bukhari, C. J. J. Lee, D. L. Yung, D. Chi and T. S. A. Hor, Chem. Comm, 2011, 47, 10653-10655. [8] Y. Liu, K. H. Lee, J. J. Vittal and T. S. A. Hor, J. Chem. Soc., Dalton Trans, 2002, 13, 27472751. [9] T. A. Betley, Q. Wu, T. V. Voorhis and D. G. Nocera, Inorg. Chem, 2008, 47, 1849-1861.

Poster Sessions modification of the cyclometallated ligand enables tuning of the emitting properties. Therefore, a straightforward and selective method for the functionalization of Ir complexes is highly desirable. In this contribution, we present the first example of palladium catalyzed C-H bond activation/arylation of the metallated thiophenes of fac-Ir(N^C3’-thpy)3 (1) with aryl bromides. This method allows the access to new families of Ir(III) complexes, a substantial modulation of their emissive properties being achieved [2].

electron-rich aryl chlorides under mild conditions is very important due to presence of di-ortho-substituted biaryls in numerous natural products, biologically active compounds and valuable polymeric materials. However, the high C-Cl bond strength makes their activation difficult[3]. To activate aryl chlorides several successful catalysts were used but the common problems were high temperature, long reaction duration and high catalyst loading[4]. Herein we synthesized and characterized very effective ionic ferrocene-diimine Pd(II) catalysts for aqueous phase Suzuki coupling reaction of unreactive aryl chlorides. Sodium (Na+), 1-butyl-3mithylimidazolium [Bmim]+ and tetrabuthylammonium [TBA]+ ions were selected for the ionic groups (Figure 1).

Figure 1: Synthesized catalysts

Furthermore, we report the palladium-catalysed direct regioselective functionalization of DTE (DiThienylEthene) derivatives (2) with (hetero)aryl bromides, giving rise to the formation of new photochromic compounds with either two different or two identical aryl groups. This method which tolerates several functional groups would be useful for the elaboration of photochromic metal complexes [3]. [1] D. Alberico, M.E. Scott, M. Lautens, Chem. Rev. 2007, 107,174; F. Poznan, J. Roger, H. Doucet ChemSusChem. 2008, 1, 404; J. Roger, F. Poznan, H. Doucet, Green Chem. 2009, 11, 425. [2] K. Beydoun, M. Zaarour, J. A. G. Williams, H. Doucet, V. Guerchais, Chem. Commun. 2012, 48, 1260. [3] K. Beydoun, J. Boixel, V. Guerchais, H. Doucet, Catal. Sci. Technol. 2012, DOI 10.1039/C2CY00491G. Keywords: C-H activation, Palladium, Luminescence

MS.C2.P.324

It was already known that, Suzuki coupling reaction works through active Pd(0) nanoparticules. The palladium nanoparticules generated from our reaction systems were analyzed by transmission electron microscopy (TEM). The palladium nanoparticules generated from C2a and C3a are observed to be well dispersed and have an average size average size ca. 4-5 nm. Nanoparticules derived from C2a was found denser than derived from C3a. The nanoparticules generated from C1a was analyzed by TEM and the average size of nanoparticules was found ca. -100 nm. Otherwise, experimental results showed that, C2a which ionic group is [TBA]+ was found the most effective catalyst and the effectiveness of catalysts are ranked as C2a>C3a>>C1a. The correlation between size of nanoparticules with the catalytic activity of complexes proved that [TBA]+ ions have great effects on stabilising of active Pd(0) nanoparticules. Hot filtration, Hg poisoning, PPh3 and SC2 tests were also performed in order to prove the reaction worked through the Pd(0) nanoparticules. [1] R. B. Bedford, C. S. J. Cazin, D. Holder, Coordin Chem Rev., 2004, 248, 2283-2321. [2] M. Shi, T. Zhang, W. F. Wang, X. X. Gu, Organometallics, 2008, 27 753-757. [3] M. J. Jin, D. H. Lee, Org Lett., 2011, 13, 252-255. [4] S. L. Buchwald, K. L. Billingsley, K. W. Anderson, Angew Chem Int Edit., 2006, 45, 3484-3488.

Keywords: Suzuki coupling, ferrocene, diimine, aryl chlorides

MS.C2.P.325

Ionic Ferrocene-Diimine Pd(II) Catalysts For Aqueous Phase Suzuki Reaction Murat Emre Hanhan,a Ramon Martínez-Máñez,b,c Jose Vicente Ros-Lisb. aZonguldak Karaelmas University, Science and Letters Faculty Chemistry Department Zonguldak,(Turkey).b Departamento de Quimica, Universidad Politécnica de Valencia, Camino de Vera, Valencia,(Spain). cCIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN). E-mail: [email protected]

Dehydrogenative Desulfurization of Thioureas to Give Carbodiimides Using Silane and Transition-Metal Complex Kazumasa Hayasaka,a Kozo Fukumoto,b Hiroshi Nakazawa,a a Department of Chemistry Graduate School of Science, Osaka City University, Osaka, (Japan). bKobe City College of Technology, Kobe (Japan). E-mail: [email protected]

Suzuki reaction is the most attractive palladium catalyzed cross coupling reaction which won Nobel Prize 2010, provides carboncarbon bonds easily with using arylboronic acids and aryl halides[1]. Using arylboronic acids in the reaction provides some advantages like being non-toxic, easy handling and easy finding nature. Early studies aryl iodides and aryl bromides usually used as a substrate[2]. But using aryl chlorides is more attractive due to their low cost and wide availability. On the other hand, activation of sterically hindered

Carbodiimides (RN=C=NR’) are commonly used as dehydrating agents in organic syntheses and also an organic building blocks for many chemicals because of possessing nucleophilic moieties at the nitrogen atoms and an electronphilic center at the carbon atom [1]. Carbodiimides are synthesized on an industrial scale using ureas or thioureas and phosgene (COCl2). Phosgene is known as a poisonous gas which had been used as a chemical weapon. HgO and PdO are also used to convert thioureas into carbodiimides. These oxides are also

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Several kinds of hydrosilanes and transition-metal complexes were examined for the dehydrogenative desulfurization and it was found that transition-metal complexes used did not serve as catalysts in the reaction system. The reaction of CpFe(CO)(py)(SiR3) (R = Et, Ph) with i PrN=C=NiPr generated CpFe(CO)(iPrNCN(SiR3)iPr-κ2N,C), which was isolated and found to be stable. The formation of this complex may be responsible for making the reaction system shown in the above equation non-catalytic. [1] For a review, see: A. El-Faham, F. Albericio, Chem. Rev., 2011, 111, 65576602. [2] (a) K. Fukumoto, A. A. Dahy, T. Oya, K. Hayasaka, M. Itazaki, N. Koga, H. Nakazawa, Organometallics, 2012, 31, 787-790. (b) K. Fukumoto, A. Sakai, T. Oya, H. Nakazawa, Chem. Comm., 2012, 48, 3809-3811. (c) K. Fukumoto, T. Oya, M. Itazaki, H. Nakazawa, J. Am. Chem. Soc., 2009, 131, 38-39. (d) M. Itazaki, K. Ueda, H. Nakazawa, Angew. Chem. Int. Ed., 2009, 48, 3313-3316. ibid, 48, 6938. (e) H. Nakazawa, M. Itazaki, K. Kamata, K. Ueda, Chem. Asian. J., 2007, 2, 882-888.

synthesized by copper catalyzed azide-alkyne cycloaddition reaction(CuAAC reaction). CuAAC reaction allows for introduce substituent to click-triazoles at the 1- and 4- position, so adjusting steric and electronic properties are easy in comparison to phenathroline.

Using click-triazoles as ligands for trifluoromethylation, the click-triazole copper complex indicated higher activity than copper complex coordinated classical diamine ligands such as 2,2-bipyridyl and phenanthroline.

The X-ray structure of click-triazole copper complex(1) revealed it is a dinuclear complex with iodine bridges(Figure. 1).

Figure 1. ORTEP drawing of 1

Keywords: thiourea, carbodiimide, hydrosilane

[1] E. J. Cho, T. D. Senecal, T. Kinzel, Y. Zhang, D. A. Watson, S. L. Buchwald, Science, 2010, 328, 1679. [2] M. Oishi, H. Kondo, H. Amii, Chem. Commun., 2009, 1909. [3] O. Fleischel, N. Wu, A. Petitjean, Chem. Commun., 2010, 46, 8454.

MS.C2.P.326

Keywords: Click-triazoles, Trifluoromethylation

Synthesis, Structure and Catalysis of Click-triazole Copper Complexes Hidekatsu Hiroki, Kenichi Ogata, Shin-ichi Fukuzawa. Department of Applied Chemistry, Institute for Science and Engineering, University of Chuo, Tokyo, (Japan). E-mail: [email protected] The trifluoromethyl group on an aromatic ring is found to bioactive molecules such as pharmaceutical agents or agrichemicals, so aromatic trifluoromethylation has received considerable attentions. In a landmark report, Buchwald reported a Pd-catalyzed trifluoromethylation of aryl chlorides by use of judiciously selected ancillary ligands[1]. In 2009, Amii and co-workers published seminal report on aromatic trifluoromethylation using catalytic amount of copper[2]. They suggested that the reaction proceeds through the phenanthroline-ligated copper(I) complex [(phen)CuCF3], which is stabilized by chelate effect and nucleophilicity of the CF3 moiety is enhanced by electron donation of the phenanthroline ligand. Based on these effectiveness, The phenanthroline ligand promotes the reaction of Cu-CF3 complex with aryl halides. In the present study, drawing upon Amii’s report, We expected (2-pyridyl)-substituted click-triazoles(1,2,3-triazoles) at 4-position[3], which is 2,2’-bipyridyl or phenanthroline analogues, also promote trifluoromethylation as the ligand. Click-triazoles can be simply

Copper

complexes,

MS.C2.P.327 Pt-catalyzed Formation of Alkylsilanes by Hydrosilanes and Iodoalkanes Hikaru Inubushi,a Yoshinori Yamanoi,a Hiroshi Nishihara,a aDepartment of Chemistry, School of Science, University of Tokyo, Tokyo, (Japan). E-mail: [email protected] Organosilicon compounds have attracted considerable attentions as biologically active compounds and intermediates for organic synthesis. Despite these possible utilities, the conventional synthetic methods of organosilanes have been the nucleophilic substitution of halosilanes with organometallic reagents. However, these methods are not available for the substrates with functional groups sensitive to organometallic reagents. Recently, direct arylation of hydrosilanes by aryl iodide with Pd(0)[1] or Rh(I)[2] catalyst has been developed in our laboratory. On the other hand, direct alkylation of hydrosilanes by alkyl iodides has not been reported. In general, alkyl iodides are entirely reduced by hydrosilanes even with transition metal catalysts because of the reducing ability of hydrosilanes. Therefore, it is strongly desired to develop the direct alkylation of hydrosilanes.

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toxic. Therefore, these reagents should be replaced by other non-toxic chemicals. We recently reported several examples involving strong bond cleavage in organic compounds using iron or molybdenum complex and hydrosilane [2]. We herein report the conversion reaction of thioureas into carbodiimides involving C=S double bond cleavage using a transition-metal complex. A solution of an equimolar amount of iPrNHC(S)NHiPr, (EtO)3SiH, and CpFe(CO)2Me (1) or CpMo(CO)3Me (2) in THF was heated at 60 ºC for 24 h. The GC-MS spectra of the product showed the formation of iPrN=C=NiPr in both cases. The yields were 59% for 1 and 13 % for 2.

Poster Sessions In this study, we found that Pt(0) catalyst could successfully catalyze the alkylation of tertiary silanes with iodoalkanes. Reaction optimization clarified that Pt(PtBu3)2 could facilitate the expected coupling reactions in good to high yields (Table 1). Furthermore, this cross-coupling reaction was proved to be applicable to substrates with several functional groups such as esters (2), cyano (3) or chlorine (4). These groups would not be tolerated in the conventional methods. Heteroaromatic cycle (5) and benzyl group (6) on hydrosilane could also be employed. As an application of this reaction, an organosilicon incectcide, Silafluophen (7), was synthesized straightforwardly in a good yield. Table 1. Optimized conditions and representative results.

[2] M[1] Polyoxometalate Chemistry From Topology via Self-Assembly to Applications, ed. M. T. Pope and A. Müller, Kluwer Academic Publishers, Dordrecht, Netherlands, 2001. T. Pope, T. Yamase (Eds.), Polyoxometalate Chemistry for Nanocomposite Design, Kluwer, Dordrecht, The Netherlands, 2002. [3] C. L. Hill, J. Mol. Catal. A: Chem., 2007, 262, 2. [4] Comprehensive Coordination Chemistry II: From Biology to Nanotechnology, ed. J. A. McCleverty and T. J. Meyer, Elsevier, Oxford, 2004. [5] Ojima, Y.; Yamaguchi, K.; Mizuno, N. Adv. Synth & Catal. 2009, 351, 1405.

Keywords: reactions

Polyoxometalate,

Catalytic

activity,

Protection

MS.C2.P.330 Hydrogen Production from Water Using Nickel Complex with Non-innocent Ligand Tatsuya Kawamoto, Manabu Mitsuhashi, Yuhei Miyazaki, Department of Chemistry, Kanagawa University, Hiratsuka, (Japan). E-mail: [email protected]

[1] A. Lesbani, H. Kondo, Y. Yabsaki, M. Nakai, Y. Yamanoi, H. Nishihara, Chem. Eur. J., 2010, 16, 13519-13527. [2] Y. Yamanoi, H. Nishihara, J. Org. Chem., 2008, 73, 6671-6678.

Keywords: platinum catalyst, alkylsilane, cross-coupling

MS.C2.P.329 Investigation of the Catalytic Activity of Lacunary Polyoxometalates Through Changing the Substituted Metal Atom in Their Structures Davud Karimian,a Bahram Yadollahi,a Valiollah Mirkhani,a a Department of chemistry, University of Isfahan, (Iran). Email: Davud. [email protected] In recent years, polyoxometalates have received considerable attention because of their great ability in analytical chemistry, catalysis, medicine and material science [1]. Interestingly, catalysis and material science are still the two main fields of applications of POMs [2,3]. Among the polyoxometalates, most of researches in catalysis utility have been assigned to Keggin structure, while working on other structures such as Wells-Dawson has remained poor [4]. Therefore, for meeting our aim to broaden the scope of catalytic activity of these compounds, we centralized our consideration on working with transition metal substituted polyoxometalate (TMSP) of WellsDawson structure and using them as a catalyst in organic reactions. Regarding the organic reactions, the choice of the protection strategy of hydroxyl groups in the organic synthetic sequence is inevitable, owing to chemoselective transformations in the presence of various functional groups [5]. In this respect, we utilized the Fe, Co, Zn, Ni substituted polyoxometalates in the alcohol protecting reactions, and since among the protecting groups, HMDS and DHP are more favorable ones, we only worked on them. Operating protecting reactions on many alcohols includes aliphatic and benzylic one, we observed that remarkable results come from Fe-substituted catalyst for protecting with HMDS, and from Co-substituted one for protecting with DHP. In addition, the present methodology offers several advantages such as short reaction times, high yields, simple procedure, non-toxicity and low cost.

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The production of hydrogen from water by visible light is one of the most challenging tasks for alternative energy resources. The multicomponent systems employing a photosensitizer, a water reduction catalyst, a sacrificial reductant, and an electron relay have been widely studied as a photocatalytic system for hydrogen generation. However, in their systems expensive catalysts such as colloidal platinum have frequently been employed, and hence developing alternative cheaper catalyst is an important area of research for hydrogen production. On the other hand, we have focused on studing the metal complexes with non-innocent ligands, and then succeeded in preparating some redox-active nickel complexes with N,S donor atoms [1]. Here we report that a nickel complex with non-innocent ligand exhibits good catalytic activity as a less expensive catalyst for the photocatalytic production of hydrogen from water when paired with Ru(bpy)32+, EDTA∙2Na, and MV2+.

[1] T. Kawamoto, K. Takeda, M. Nishiwaki, T. Aridomi, T. Konno, Inorg. Chem., 2007, 46, 4239-4247.

Keywords: hydrogen production, nickel complex, non-innocent ligand

MS.C2.P.331 Synthesis of Cyclic Carbonates from CO2 and Epoxides Using Highly Active Al(III) catalysts Nicola Kielland, Christopher J. Whiteoak, and Arjan W. Kleij, Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007, Tarragona, Spain. E-mail: [email protected]

Poster Sessions

Here we present the results of DFT calculations of RnX–CN (RnX = H2N, Me2N and MeO) bond cleavage in the presence of an unsaturated iron(II) silyl complex, CpFe(CO)SiMe3 (reaction 1), which will be compared with the results for Me–CN bond cleavage.

Scheme 1.

Various groups have reported a variety of metal based catalytic systems capable of catalyzing this cycloaddition reaction,[3] but the discovery of a catalyst system which is highly active under mild reaction conditions still remains a challenge. Our group, recently described a new family of iron(III) based catalysts, capable to efficiently catalyze the cycloaddition of carbon dioxide to epoxides under mild reaction conditions and showing amplified substrate scope.[4] In this contribution, we present an analogous family of aluminum(III) catalysts which under solvent-free conditions allows for high conversion levels under comparative mild reaction conditions using low catalyst loadings. Kinetic data will also be presented that unambiguously demonstrates the high potential of these systems in organic carbonate formation. [1] M. Aresta, Carbon Dioxide as a Chemical Feedstock, Wiley-VCH, 2010. [2] T. Sakakura, J.-C. Choi and H. Yasuda, Chem. Rev., 2007, 107, 2365. [3] M. North, R. Pasquale and C. Young, Green Chem., 2010, 12, 1514. [4] C. J. Whiteoak, E. Martin, M. Martínez Belmonte, J. Benet-Buchholz, and A. W. Kleij, Adv. Synth. Catal. 2012, 354, 469.

Keywords: Carbon dioxide, cycloaddition, epoxides, aluminum complexes

MS.C2.P.332 A DFT Study of RnX–CN (X=C, N, and O) Bond Cleavage by an Iron Silyl Complex Nobuaki Koga,a AbdelRahman A. Dahy,b Hiroshi Nakazawa,c a Graduate School of Information Science, Nagoya University, Nagoya, (Japan). bDepartment of Chemistry, Faculty of Science, Assiut University, Assiut (Egypt). cDepartment of Chemistry, Graduate School of Science, Osaka City University, Osaka (Japan). E-mail: [email protected] Cleavage of inert bonds such as C−H, C−C, C−N, and C−O bonds could provide new species that are useful in organic synthesis. A number of experimental and theoretical studies focusing on cleaving such inert bonds in the presence of transition metal complexes have been published. Within C–C bond cleavage, C-CN bonds in organotitriles are more difficult to cleave than C-C bonds in alkanes. We recently demonstrated that in the reaction of acetonitrile with an iron complex having a silyl ligand the C-CN bond is broken and that density functional theory (DFT) calculations clarified the reaction mechanism as shown below.[1] This type of reaction is called a silylmigration-induced reaction (SiMI reaction).[2]

CpFe(CO)SiMe3 + RnXCN → CpFe(CO)(XRn)(CNSiMe3) (RnX=Me, NH2, NMe2, OMe) (1)

The calculations showed that the most favourable pathway starts with the formation of complexes containing nitriles in the end-on coordination mode, which then isomerizes to side-on coordination to facilitate silyl group migration to nitrile N atom (NCN). This is followed by dissociation of NCN and coordination of amino N atom or methoxy O atom to the Fe atom. Dissociation of NCN has the largest activation energy in the sequence of reactions and thus it is the ratedetermining step. This is in good agreement with the isolation of similar intermediates in experiments that have been identified by X-ray crystallography. Finally, the cleavage of R2N−CN or MeO–CN bonds takes place with small activation energies. This mechanism is similar to that shown for C­–CN bond cleavage; however, comparing these reaction profiles with that of Me–CN, we found that the Me–CN bond is activated by the βCC agostic interaction with Fe, whereas the N–CN and O–CN bonds are activated by ring strain in the three-membered ring that is formed by coordination of the amino N atom or methoxy O atom to Fe. [1] H. Nakazawa, T. Kawasaki, K. Miyoshi, C. H. Suresh, N. Koga, Organometallics, 2004, 23, 117. [2] K. Fukumoto, A. A. Dahy, T. Oya, K. Hayasaka, M. Itazaki, N. Koga, H. Nakazawa, Organometallics, 2012, 31, 787.

Keywords: reaction mechanism, bond cleavage, density functional theory calculation

MS.C2.P.333 The Coordination Chemistry of Co Complexes Containing SNS Ligands and their Application as Biomimetic Catalysts for Paraffin Activation Lynette Komarsamya, Holger B. Friedricha and Muhammad D. Balaa a Department of Chemistry, University of KwaZulu-Natal, Durban, (South Africa). E-mail: [email protected] Paraffins, also known as alkanes or saturated hydrocarbons, form major components of crude oil and natural gas [1]. Due to the relatively inert nature of the paraffinic C−H bond, a great deal of research has been done in the area of activation and functionalisation of these unreactive compounds. One of the most developed methods to date is via catalysis whereby a catalyst is used to convert the hydrocarbon into desired products, most often oxygenates like alcohols, ketones, aldehydes and carboxylic acids. This research employs cobalt complexes containing SNS ligands as catalysts for paraffin activation. Cobalt is a relatively cheap metal which is low in toxicity as compared to other heavier metals like Ru, Rh and Ir. With the inspiration of enzymes like monooxygenases [2] which are highly active catalysts for paraffin oxidation, this research is based on Co incorporating sulfur- and nitrogen-based coordination compounds, with the aim of mimicking the biological enzymes. Seven complexes have been successfully synthesized and

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Chemical processes based on carbon dioxide as a renewable carbon source currently receive considerable interest.[1] However, in most reported cases high pressure, high temperature, long reaction times or a combination thereof is often required as a consequence of the inert nature of CO2.[2] Cycloaddition of carbon dioxide to epoxides (Scheme 1) is known to yield cyclic carbonate products and is a much more sustainable methodology than the current synthetic process that is based on phosgene. Cyclic carbonates are particularly interesting due to their use as aprotic polar solvents, pharmaceutical intermediates and electrolytes in secondary batteries.

Poster Sessions characterized via IR, elemental analysis and X-ray crystallography. Out of the seven complexes, five contain a pyridine backbone (Figure 1) and two have an amine backbone (Figure 2). The substituents (R) on the sulfur atoms were also varied to investigate electronic and steric effects on coordination behavior and catalytic efficiency of the complexes. The complexes were tested as catalysts for the activation of paraffinic C−H bonds towards the formation of oxygenated products: octanol, octanone, octanal and octanoic acid from the substrate n-octane. R= Methyl Ethyl Butyl Phenyl Cyclohexyl

Figure 1: Structure of pyridine-based Co(SNS) complexes synthesized.

R= Ethyl Butyl

Figure 1: Structure of amine-based Co(SNS) complexes synthesized.

[1] E.I. Stiefel, Dithiolene Chemistry: Synthesis, Properties and Applications, John, Wiley and Sons 2004. [2] J. Buecheler, N. Zeug, H. Kirch, Angew.Chem. Int.Ed. Engl, 1980, 19, 645. [3] R. Humphry-Baker, C.A. Mitsopoulou, D. Katakis, and E. Vrachnou, J.Photochem.Photobiol.A:Chem., 1998, 114, 137144. [4] P.W. Du, K. Knowles, R. Eisenberg, J.Am.Chem.Soc., 2008, 130, 12576.

Keywords: platinum, dithiolenes, photocatalysis

MS.C2.P.336 Palladium-Catalyzed C–H Bond Activation: Catalytic Activities and Mechinistic Insights Hon Man Lee,a Ponnamaneni Vijay Kumar,a Jhen-Yi Lee,a aNational Changhua University of Education, Department of Chemistry, Changhua, (Taiwan). E-mail: [email protected] In this presentation, we will report our group’s recent results on using palladium(II) and palladium(0) complexes bearing N-heterocyclic carbene ligands in catalyzing direct arylation reactions to construct heteroaromatic building blocks.[1] The direct arylation reactions, involving the C–H bond activation as a key step in the catalytic cycle, are attracting interests because of fewer synthetic steps and less waste produced than classical coupling reactions. A wide range of imidazoles were successfully utilized in the coupling reactions with aryl halides. Since palladacycles are usually key intermediates in palladiumcatalyzed C–H functionalization, understanding the fundamental aspects of cyclometalation processes can provide useful insights into the mechanistic features of palladium-catalyzed C–H functionalization reactions. Therefore, we will also present our recent finding on a novel cyclometalation pathway to form CC-type palladacycles (Scheme 1).

[1] J. A. Labinger and J. E. Bercaw, Nature, 2002, 417, 507-514. [2] D. Mansuy, Pure and Appl. Chem., 1990, 62, 741-746.

Keywords: Co catalyst, SNS ligand, biomimetic

MS.C2.P.335 Complexes of Pt: Synthesis, Characterization and applications in photocatalysis Eugenia Koutsouri,a Christiana A. Mitsopoulou,a aInorganic Chemistry Laboratory, Department of Chemistry, University of Athens, Panepistimiopolis Zografou, 15771 Athens, (Greece). Email: [email protected] Neutral metal bisdithiolene and mixed diimine-dithiolate complexes have attracted the interst of inorganic chemists and physicists for multiple reasons [1]. In 1990’s some disdithiolene [2] and trisdithiolene [3] complexes had been reported as catalysts for the photocatalytic splitting of water, but they did so only inefficiently. Recently, the usage of platinum (II) diimine dithiolene complexes as senzitizers for hydrogen production was also cited [4]. Herein, we present our attempts to improve the stability and the photocatalytic action of mixted diimine dithiolate complexes. For this purpose, we have synthesized and characterized monometallic and bimetallic mixed dithiolate-diimine complexes with NMR, FT-IR, UV-Vis and cyclic voltammetry (CV). The bimetallic complex of Pt, was prepared by organic bridges that permitted the charge transfer among them. The photocatalytic action was tested in systems containing a sacrificial donor (EDTA or thiethylamine) and/or an electron acceptor. The precursors of the bimetallic complex have also been tested for H2 production.

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[1] P. V. Kumar, W.-S. Lin, D. Nandi, H. M. Lee, Organometallics, 2011, 20, 5160-5169.

Keywords: palladium, C-H bond activation, catalysis

MS.C2.P.337 Catalytic Applications Of Late Transition Metal Complexes Of Dendritic Schiff Base Ligands Selwyn Mapolie,a Jane Mugoa Rehana Malgas, a Department of Chemistry and Polymer Science, Stellenbosch University, Stellenbosch, (South Africa). E-mail: [email protected] Metallodendrimers have in recent years emerged as an useful alternative to conventional catalytic systems (homogeneous as well as heterogeneous) [1]. The application of metallodendrimers as catalyst precursors in several different processes has received increasing attention in the last couple of years [2-3]. In this paper we highlight some of our work over the last few years where we have employed dendrimeric catalysts in the transformation of various organic substrates including unsaturated hydrocarbons such as a-olefins, functionalized alkenes, alkynes as well as cyclic esters.

Poster Sessions Examples of dendritic catalysts developed in our group are shown in Figure 1. Several of the metallodendrimers developed by us have found use as catalysts in a range of different reactions. Thus for example Pd metallodendrimers have been employed as ethylene and phenyl acetylene polymerization catalysts while nickel systems have been effective as olefin oligomerization catalysts, outperforming its mononuclear analogues. We have recently found Zn metallodendrimers to be active in ring opening polymerization of lactides showing high conversion of the monomer under relatively mild conditions. Some of the main results from these reactions are highlighted in this paper.



immediate conversion of [Fe(tpena)(OIC6H5)]2+ to [Fe(tpena)]2+, and the concurrent production of methylphenylsulfoxide:

This O atom transfer reaction can be converted to selective high yield catalytic oxygenation (TON 1600 in about 2 hours with no indication of catalyst decomposition). The active oxidant is proposed to be the Fe(V) species, [FeVO(tpena)]2+. The amino acid, tpenacontains one carboxylate donor, the remaining donor are neutral N atoms. Thus [FeVO(tpena)]2+ is an excellent chemical mimic for high valent non-heme iron and we propose that coordinative flexibility and bifunctionality of the tpena- ligand play biomimetic roles. Thus [FeIII(tpena)(OIC6H5)]2+ is an isolable protected form of highly reactive [FeVO(tpena)]2+.

Ni Cyclam cored Zn DAB cored metallodendrimer metallodendrimer Figure 1: Examples of metallo dendrimeric catalysts.

[1]. D. Méry, D. Astruc, Coord. Chem. Rev. 2006, 250, 1965. [2]. G. Smith, R. Chen, S. Mapolie, J. Organomet. Chem. 2003, 673, 111. [3]. R. Andrés, E. de Jesus, F. J. de la Mata, J. C. Flores, R. Gomez, J. Organomet. Chem. 2005, 690, 939.

Keywords: metallodendrimers, dendritic catalysts, dendrimer complexes

A Fe(III)-iodosylbenzene complex: Masked Fe(V)-oxo Christine J. McKenzie,a Anders Lennartson,a aDepartment of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense, (Denmark). E-mail: [email protected] Iodosylarenes are an important class of oxygen atom transfer reagents in organic synthesis, often used in conjunction with transition metal-based catalysts. The consensus mechanism for the oxidation of substrates is that hypervalent M-oxo species, generated from the reaction of the catalyst and the iodsoylarene, are the active oxidants. In corroboration, O atom transfer from iodosylarenes to [LMn+] complexes has been used as a strategy to for the synthesis of hypervalent [LM(n+2)+O] species:

On a few occasions transient species assigned to the intervening metal-iodosylarene adducts depicted in the above equation [LMn+OIAr], have been spectroscopically identified.[1] We have structurally characterised the first example of a metal iodosylbenzene adduct [2] using the monoanionic hexadentate ligand N,N,N’-tris(2-pyridylmethyl)ethylendiamine-N’-acetate (tpena-)[3]. The Xray structure of the orange seven-coordinated Fe(III) complex cation in [Fe(tpena)(OIC6H5)](ClO4)2 is depicted in the scheme below. [Fe(tpena)(OIC6H5)]2+ is stable in acetonitrile solution for hours however the addition of substrates, e.g., thioanisole, results in its

[1] W. Nam, S. K. Choi, M. H. Lim, J.-U. Rhode, I. Kim, J. Kim, C. Kim, L. Que Jr., Angew. Chem., Int. Ed., 2003, 42, 109-111.; F. F. Pfaff, S. Kundu, M. Risch, S. Pandian, F. Heims, I. Pryjomska-Ray, P. Haack, R. Metzinger, E. Bill, H. Dau, P. Comba, K. Ray, Angew. Chem., Int Ed., 2011, 50, 1711-1715. [2] A. Lennartson, C.J. McKenzie, Angew. Chem., Int Ed., 2012, accepted. [3] M. S. Vad, A. Nielsen, A. Lennartson, A. D. Bond, J. E. McGrady, C. J. McKenzie, Dalton Trans, 2011, 40, 10698-10707.

Keywords: Bioinorganic, Fe(V), O-atom transfer

MS.C2.P.339 Zinc(II) Complex of Pyrrolidine-fused Chlorin Functioning as a Green Oxidation Catalyst Kazuhiro Moriwaki,a Akihiro Nomoto,b Akiya Ogawa,b Shigenobu Yano,c Haruo Akashi,a,* aResearch Institute for Natural Sciences, Okayama University of Science, Okayama, (Japan). bGraduate School of Engineering, Osaka Prefecture University, Osaka, (Japan). c Graduate school of Materials Science, Nara Institute of Science and Technology, Nara, (Japan). E-mail: [email protected] Novel zinc(II) complex of 5,10,15,20-tetrakis(pentafluoro-phenyl)2,3-(methano(N-methyl)iminomethano)chlorin (=H2TFPC [1]) was prepared by the reaction of H2TFPC with ZnCl2 in the presence of Et3N. The compound, 5,10,15,20-tetrakis(pentafluorophenyl)2,3-(methano(N-methyl)imino-methano)chlorinato)zinc(II) (= Zn(TFPC)), was characterized by 1H, 19F NMR spectroscopies, MALDI-TOF-MASS spectroscopy, and elemental analysis.

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P.MS.C2

MS.C2.P.338

Poster Sessions band should be assigned as a 2e—reduction product, such as 1-benzyl1,4-dihydronicotinamide (NDBZH). The feature of the mechanistic reduction in the system of NDBZ+ was investigated using several kinds of alcohols, primary, secondary, and tertiary alcohols. The Zn(II)-LNH systems with primary and secondary alcohols exhibited increase in the absorption intensity at 350 nm, due to reduction of NDBZ+. In case using tertiary alcohol as the substrate, no spectral change at 350 nm was observed. The differences in reactivities of alcohols in the Zn(II)LNH system suggest hydride-transfer mechanism of NDBZ+ reduction in Zn(II)-LNH system. Here, we have successfully synthesized a new cage-type mononuclear Zn(II) complex with the structure and function of ADH. Further studies on this system are in progress. As already mentioned in our previous report, H2TFPC generate singlet oxygen (1O2) by irradiation of light and 1O2 generation is enhanced by the introduction of heavy metal ions (for examples, Pd or Pt) into the frame [2]. The singlet oxygen quantum yield of Zn(TFPC) is about 1.5 times higher than that of H2TFPC. Zn(TFPC) shows an excellent catalytic activity for highly selective oxidation of benzylamines to produce directly the corresponding N-(benzylidene)benzylamine derivatives under atmosphere of oxygen and light irradiation. Details will be discussed. [1] M. Gałęzowski, D. T. Gryko, J. Org. Chem. 2006, 71, 5942-5950. [2] M. Obata, S. Hirohara, R. Tanaka, I. Kinoshita, K. Ohkubo, S. Fukumizu, M. Tanihara and S. Yano, J. Med. Chem. 2009, 52, 2747-2753.

Keywords: Metallochlorin, Photosensitizer, Green oxidation

MS.C2.P.340 Structure and Reactivity of a Cage-type Zn(II) Complex as a Functional Model of Alcohol Dehydrogenase Masakazu Murase,a,b Tomohiko Inomata,a Tomohiro Ozawa,a Shigeyuki Masaoka,b.c Yasuhiro Funahashi,a,c Hideki Masuda,a aNagoya Institute of Technology, Gokiso, Syowa, Nagoya 466-8555 (Japan). bInstitute for Molecular Science, National Institutes of Natural Sciences, Myodaiji, Okazaki 444-8585 (Japan). cJST-PRESTO (Japan). E-mail: [email protected] In few decades, various biomimetic metal complexes have been synthesized as a functional model of the active metal sites of metalloenzymes, and a lot of findings have been obtained for understanding their reaction mechanisms. However, it is generally very difficult to mimic the active metal centers with a cooperatively working coenzyme. We are recently trying to construct a biomimetic model compound of alcohol dehydrogenase (ADH),1) having nicotinamide adenine dinucleotide (NAD+) as the coenzyme. In this protein, NAD+ interacts to the Zn(II) center through the hydrogen bonds with a ligating water molecule. In the proposed reaction mechanism of ADH,2) an ethoxide binds to the Zn(II) center, and the electron-deficient nicotinamide moiety of NAD+ could be reduced by hydride-transferring from the ligating ethoxide, to generate NADH and acetaldehyde as the products. In the model study using a cage type ligand, LNH, the Zn(II) ion binds to one of the three coordination sites inside of LNH, as a host space for the guest molecule. The structure of a mononuclear Zn(II)-LNH complex with ancillary ligands, such as acetate ions, was confirmed by 1 H-NMR and X-ray single crystal structure analysis. For this system, 1-benzylnicotinamide (NDBZ+) was used as the NAD+ analogue. When the Zn(II)-LNH complex reacted with various alcohols in the presence of NDBZ+, an intensity of absorption band near 350 nm increased, whose

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Figure 1. Schematic structure showing assembly of an active Zn(II) ion and a cofactor model, ND+, inside a cage type ligand, LNH.

[1] E. T. Young, et al., Mol. Cell. Biol., 1985, 5, 3024-3034. [2] R. Meiljers, et al., J. Biol. Chem., 2001, 276, 9316-9321. Keywords: Bio-mimetic model, Alcohol dehydrogenase

MS.C2.P.341 The C–H activation of n-octane by cobalt and iridum PNP pincer complexes Dunesha Naicker, Holger B. Friedrich, School of chemistry and physics, University of KwaZulu-Natal, Westville Campus, Durban, South Africa. E-mail: [email protected] The selective activation of C-H bonds by transition metal complexes allows the development and improvement of catalytic processes and has been a target for both inorganic and organic chemists [1]. Paraffin activation has practical implications in the replacement of current petrochemical feedstocks (olefins), by utilising economical and easily accessible alkanes, which may result in more efficient strategies for fine chemical synthesis and the proficient use of energy [2]. However, the chemical inertness of paraffins limits their conversion to more valuable products [2]. Several pincer chelate complexes are utilised in stoichiometric and catalytic C-H activation [3]. These pincer ligands have attained much interest in that they are part of a system, which displays high stability, activity and variability [4]. The PNP pincer ligands are terdentate, enfolding around the metal center creating bonds in between and on opposite sides of the metal [3]. Four pincer ligands have been successfully synthesised (Fig. 1) and complexed to the transition metals cobalt and iridium. 31P NMR was used to observe the shift in the phosphorous peak of the ligands. The νP-N band shifts, in the infrared spectra, were indicative of complexation to the metal. Other characterisation techniques include elemental analyses, mass spectrometry and thermogravimetric analyses. The catalysts (pincer complexes) were tested in the oxidation of n-octane with varied ratios of substrate to the oxidising agent (tert-butyl hydroperoxide). The solvent systems utilised were dichloromethane

Poster Sessions and acetonitrile. The optimum ratio of substrate to oxidant was 1:5. In dichloromethane, the iridium catalysts gave the highest conversion of 7% whilst the cobalt catalysts were most selective towards the ketones (60%). When acteonitrile was used as the solvent system, no catalytic conversion was observed with the iridium catalysts. However, a conversion of 12% was observed with the cobalt catalyst, with a selectivity of 70% towards the ketones.

Figure 1: Structure of the PNP ligands. R1 iso-propyl, pentyl, cyclohexyl and benzyl. [1] Weng, W.; Guo, C.; Moura, C.; Yang, L.; Foxman, B. M.; Ozerov, O. V. Organometallics. 2005, 24, 3487. [2] Labinger, J. A.; Bercaw, J. E. Nature. 2002, 417, 507. [3] Xu, X.; Xi, Z.; Chen, W.; Wang, D. J. Coord. Chem. 2007, 60 (1), 2297. [4] Benito-Garagorri, D.; Kirchner, K. Acc. Chem. Res. 2008, 41, 201.

Keywords: C-H avtivation, PNP pincer ligands, n-octane

MS.C2.P.342

MS.C2.P.343 Resorcin[4]Arene-Capped Porphyrin Catalysts for Selective Oxidation of Octane Hitesh Parekh, Pramod Pansuriya, Michael McKay, Thandanani Cwele, Glenn Maguire and Holger Friedrich, School of Chemistry, University of KwaZulu-Natal, Westville Campus, Durban (South Africa). E-mail: [email protected] Paraffin species and olefins are the major byproducts of thermal cracking of waxes, polymerization, oligomerization, dehydrogenation, chlorination, and dehydrohalogenation processes in the petroleum industries. It is a challenging job to convert these species to beneficial commodity chemicals. Paraffins also offer greener and low energy routes to valuable chemicals. During the past decade, remarkable progress has been reported in catalytic epoxidation, hydrogenation, aziridination, and cyclopropanation of paraffin and olefins.[1-3] However, the development of new tools is still crucial, particularly in the case of catalytic oxidation. Significant improvement is necessary from both practical and mechanistic points of view, such as selective, stable and high turnover catalytic systems. The potential benefits of developing an armamentarium for the selective conversion of alkanes to more valuable oxidized products such as alcohols, aldehydes, oxiranes, carboxylic acids and derivatives are enormous. To achieve this, new resorcin[4]arene-capped porphyrin catalyst (Figure) having –O(CH2)2O- (four atom) and –O(CH2)4O- (six atom) ether bridges and 2-phenylethyl feet have been synthesized. The synthesis of the target molecules includes bromination, etherification, lithiation, hydrolysis, and microwave assisted chemistry.[4] The characterization of all intermediates and final products were done by IR, NMR, and mass spectrometry. The catalytic testing of n-octane will be reported, including using in situ methodology making use of the appropriate metal salts and co-oxidants.

The hydrolysis of phosphate esters has an important role in the WMD countermeasures such as chemical agents neutralization and/or bacterial/viral decontamination. We are investigating into synthesizing new homogeneous metal-based catalysts that will enhance the catalytic reaction of the hydrolysis of phosphate esters. The catalysts can be tuned sterically and electronically, through a careful selection of ligands, neutral molecules, or ions bound either covalently or electrostatically to the catalytically active metal ion center. Our goal is to further enhance hydrolysis using a novel approach that combines plasmonics and electronically-modulated catalysis - via molecular tethers attached to gold nanoparticle (NP) surfaces - with additional desolvation effects, decreased conformational freedom, cooperative effects and depth profiling study of the multi-metallic catalytic centers at gold nanoparticle surfaces. We will describe our efforts towards the synthesis of novel bifunctional 2,2’-bipyridyl (bipy) ligands, subsequent coordination to copper, cooperativity with arginine- and choline-like tethers, and depth profile studies of the catalytic centers for the enhanced hydrolysis of phosphodiester bonds. This work received support from the Defense Threat Reduction Agency-Joint Science and Technology Office for Chemical and Biological Defense (MIPR #B102405M and B112542M).

P.MS.C2

Heterobifunctional 2,2’-bipyridyl ligands for homogeneous catalytic hydrolysis of phosphate esters on a gold nanoparticle platform R. Nita,a S. A. Trammell,b J. R. Deschamps,b D. A. Knight,a aChemistry Department, Florida Institute of Technology, Melbourne, FL 32901, USA. bNaval Research Laboratory, Washington, DC 20375, USA. E-mail: [email protected]

Figure Structure of the resorcin[4]arene-capped porphyrin catalyst [1] Z. Gross, N. Galili, L. Simkhovich, Tetrahed. Let., 1999, 40, 1571-1574. [2] A. Olivos Suarez, H. Jiang, X. Zhang, B. de Bruin, Dalt. Trans., 2011, 40, 5697-5705. [3] B. Lane, K. Burgess, Chem. Rev., 2003, 103, 2457-2474. [4] M. McKay, T. Cwele, H. Friedrich, G. Maguire, Org. Biomol. Chem., 2009, 7, 3958-3968.

Keywords: resorcin[4]arene, paraffin, catalysis

Keywords: Supported Catalysis, Plasmonics, Gold Nanoparticles

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Poster Sessions MS.C2.P.344 Cobalt Porphyrins Mediated Living Radical Polymerization Chi-How Peng, Tsung-Han Tu, Chen-Shou Hsu, Department of Chemistry, National Tsing Hua University, Hsinchu, (Taiwan). Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu, (Taiwan). E-mail: [email protected] Living radical polymerization (LRP) of methyl acrylate and vinyl acetate mediated by cobalt porphyrin complexes [1-3] has been performed in different solvents with various initiators. This systematic study provides an in-depth understanding of the influences of thermodynamic factors to the catalytic process and broadens the application of this method. Three periods were observed in this cobalt mediated LRP: 1) induction period, in which the radicals were trapped by cobalt(II) complex to form organo-cobalt(III) complex and thus no polymerization occurred; 2) fast polymerization, which mediated by organo-cobalt(III) complex via a degenerative transfer pathway. The polymerization rate is mainly determined by the concentration of initiator; 3) slow polymerization, which dominated by a reversible termination pathway and most of the radicals are from the dissociation of organo-cobalt(III) complex. [4] Solvent effect is significant to polymerization rate and the polydispersity (PDI) due to the change of the rate constants of propagation and chain transfer reactions. Sulfonated cobalt porphyrin complexes can mediate living radical polymerization in aqueous phase [5] under acidic or basic conditions which usually cause the decomposition of catalysts in other LRP techniques. Homo- and block copolymers of acrylic acid and acrylamides have been synthesized using cobalt tetra(3,5disulfonatomesityl)porphyrin ((TMPS)CoII). Linear evolution of molecular weight versus conversion and low polydispersity (PDI < 1.5) were observed during the polymerization. Kinetic plots indicate that the polymerization is the same mediated by both degenerative transfer and reversible termination pathways. [1] B. B. Wayland, G. Poszmik, S. L. Mukerjee, M. Fryd, J. Am. Chem. Soc., 1994, 116, 7943-7944. [2] C.-H. Peng, J. Scricco, S. Li, M. Fryd, B. B. Wayland, Macromolecules, 2008, 41, 2368-2373. [3] C.-H. Peng, S. Li, B. B. Wayland, Inorg. Chem., 2009, 48, 5039-5046. [4] B. B. Wayland, C.-H. Peng, X. Fu, Z. Lu, M. Fryd, Macromolecules, 2006, 39, 8219-8222. [5] C.-H. Peng, M. Fryd, B. B. Wayland, Macromolecules, 2007, 40, 6814-6819.

Keywords: cobalt, porphyrin, living radical polymerization

MS.C2.P.345 Natural Biopolymers as Transition Metal Coordinating Agent for the Preparation of Nanoparticulate Catalysts Ana Primo, Instituto Universitario de Tecnología Química CSIC- UPV, Universidad Politécnica de Valencia, Av. De los Naranjos s/n, 46022 Valencia, Spain. E-mail:[email protected] Natural polysaccharides such as chitosan and alginate can be obtained in large quantities from biomass wastes. This biopolymers are constituted by glucose units combined with n-acetyl glucosamine and glucosamine (case of chitosan) or glucose together with glucuronic and maluronic acids. The fibrils of these polysaccharides are mostly unbranched and they can be soluble in water under acid (case of chitosan) or basic conditions (case of alginate). In aqueous solution they tend to agglomerate and by precipitation they can form large sphere particles of millimetric size. One of the best known applications of these natural biopolymers derives from their availability to coordinate with transition metals in water and in this way, these materials can be used for the removal of toxic metal ions present in waste waters.

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In the present communication a novel methodology for the formation of noble metal nanoparticles or nanoparticulated metal oxides will be described as well as their activity of this materials to act as (photo)catalyst for organic reactions or chemical transformations. [1, 2] The method (see Scheme below) has as first step the strong coordination of metal ions in aqueous solution to the functional groups present in the fibrils of the biopolymers. Supercritical drying of transition metal containing biopolymers leads to samples with high surface area and porosity that after calcination leads to the noble metal or metal oxides, the key feature being the nanometric size of the particles due to the templating effect of the biopolymers fibrils in the process of metal ion capture and nanoparticle formation. The resulting material exhibits catalytic activity for the C-C cross-coupling reaction (case of gold nanoparticles) or photocatalytic activity for water splitting (case of TiO2 and CeO2)

Scheme. Synthesis of CeO2 nanoparticles by biopolymer templated process; i) alginate precipitation by (NH4)2Ce(NO3)6; ii) aging (19 h); iii) supercritical CO2 drying; iv) air calcination. [1] A. Primo, A. Corma, H. Garcia, Phys. Chem. Chem. Phys. 2011, 13, 886. [2]A. Primo, T. Marino, A. Corma, R. Molinari, H. Garcia, J. Am. Chem. Soc. 2011, 133, 6930.

Keywords: Alginate, Chitosan, Coordination of metals and biopolymers

MS.C2.P.346 H2 Catalyzes Reversible C—H and N—H Bond Formation in Organometallic Ir Complexes Nuria Rendón, José E. V. Valpuesta, Ana Zamorano and Ernesto Carmona. Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica, Consejo Superior de Investigaciones Científicas-Universidad de Sevilla, Sevilla (Spain). E-mail: nuria@iiq. csic.es Dihydrogen (H2) is an extremely important reactant for chemical synthesis and a relatively recent useful ligand that can be activated by both transition metal and main group elements. In this communication we report that H2 catalyzes with high efficiency a prototropic rearrangement of aminopyridinate ligands bound to a (h5-C5Me5)Ir(III) unit. Isomerisation of the aminopyridinato ligand in complex 1, in the presence of H2 (ca. 6 mol %), was observed to form complex 2 that contains a chelating h3-benzylic/pyridine moiety. Formation of 2 requires activation of a benzylic C—H bond of 1, with formal hydrogen transfer to the amido nitrogen. An equilibrium is established with a half-life, t1/2 of ca. 2.5 h favouring slightly complex 2 (Keq ~ 4). Equilibration of the two cations implies reversible formation and cleavage of H—H, C—H and N—H bonds.

Poster Sessions

[1] a) C. White, A. J. Oliver, P. M. Maitlis, Dalton Trans. 1973, 1901-1907; b) T. M. Gilbert, R. G. Bergman, J. Am. Chem. Soc. 1985, 197, 3502-3507.

Keywords: Dihydrogen catalysis, C—H activation, ligand isomerization

MS.C2.P.349 Outer Sphere O2 Activation at a Mononuclear Iron Site Martha E. Sosa-Torres, Juan P. Saucedo-Vázquez, Facultad de Química, Universidad Nacional Autónoma de México, Coyoacán, México D.F. 04510, México. E-mail: [email protected] A kinetic mechanistic study was carried out for the oxidative dehydrogenation of [FeL3]3+ (1), L3 = 1,9-bis(2′-pyridyl)-5-[(ethoxy2′′-pyridyl)methyl]-2,5,8-triazanonane in the presence of molecular oxygen. The structure of the product, the monoimine [FeL4]2+ (2), L4 = 1,9-bis(2′-pyridyl)-5-[(ethoxy-2′′-pyridyl)methyl]-2,5,8-triazanon-1ene, was determined in solution (NMR) and in the solid state (X-ray). Spectroscopic and electrochemical experiments helped to identify the iron intermediates. In addition, coupled enzymatic assays with catalase and superoxide dismutase helped to determine the nature of short-lived oxygen intermediates. It is proposed that, 2 is formed by a series of single electron oxidation reactions of the [FeL3•]2+ intermediate with O2, via outer sphere electron transfer. The experimentally determined rate law is described by a third order rate equation: -d[(FeL3)3+]/dt = kOD[(FeL3)3+][EtO-][O2] with kOD = 3.80 X107 M-2 s-1. The absence of general base catalysis, as well as the experimental and theoretical rate law expressions, support that the first reduction of O2 is the rate limiting step of the reaction. This study is compared with that [1] carried out under N2.

MS.C2.P.350 Novel Structurally Defined Oxamate-Containing Palladium(II) Catalysts for Cross Coupling Carbon-Carbon Reactions Salah-Eddine Stiribaa, Francisco Ramón Fortea-Péreza, Miguel Julve,a Francesc Lloret,a Donatella Armentanob, Giovanni De Munno,b a Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, C/. Catedrático José Beltrán 2, 46980 Paterna, Valencia,(Spain). b Dipartimento di Chimica, Universitè della Calabria, via P. Bucci 14/c, 87030 Arcavacata di Rende, Cosenza, (Italy). E-mail: [email protected] The continuous search for efficient and highly stable palladium complexes for the catalytic carbon-carbon coupling reactions, namely Suzuki and Heck reactions is of utmost importance, primarily due to their synthetic potential to generate sp-sp and sp2-sp2 carboncarbon bonds. Several approaches towards the catalyst design and its improvement have been described. Most efforts have focused on electron-poor chloroarenes by the use of highly basic, sterically hindered phosphines, N-heterocyclic carbenes (NHC), palladacycles, a large excess of coordinating ligands such as triphenylphospine or colloidal palladium nanoparticles [1]. Aiming at preparing new free-phosphine, highly stable and watersoluble palladated catalysts; we have developed new palladium(II) complexes based on the use of oxygen-nitrogen mixed donors (N,O), namely oxamate type ligands. In fact, these ligands are very versatile and their preparation is straightforward and very cheap. The electronic state and steric environment of the palladium center can be modulated by fine-tuning these ligands, in view of controlling the catalytic reactivity/selectivity of the palladium(II)-oxamate system in carboncarbon bond cross coupling processes [2]. In our communication, we present the preparation and structural characterization of a series of mono- and dinuclear oxamate-containing palladium(II) complexes with different alky/aryl-substituted oxamate ligands. The successful use of these palladium complexes as catalysts for both Suzuki and Heck reactions in a variety of solvents such as organic, water and ionic liquid media shows their potential as promising robust, multifunctional and greener catalysts for synthetic targets involving cross-coupling reactions.

[1] Reviews: V.V. Grushin, H. Alper, Chem. Rev. 1994, 94, 1047-1062. N. Miyaura, A. Suzuki. Chem. Rev. 1995, 95, 2457. [2] F. R. Fortea-Pérez, M. Julve, F. Lloret, D. Armentano, G. De Munno, E. Dikarev, S.-E. Stiriba, manuscript in preparation.

Keywords: Palladium, Oxamate, Catalysis

MS.C2.P.351

[1] J. P. Saucedo-Vázquez, V. M. Ugalde-Saldívar, A. R. Toscano, P. M. H. Kroneck and M. E. Sosa-Torres, Inorg. Chem., 2009, 48, 1214-1222.

Keywords: Oxygen activation, outer sphere mechanism, kinetic study

Earth-Abundant Transition Metal Complexes for Electrocatalytic Proton and Carbon Dioxide Reduction V. Sara Thoi,a Christopher J. Chang,a,b aUniversity of California, Berkeley, Berkeley (USA) bHoward Hughs Medical Institute, University of California, Berkeley, Berkeley (USA). E-mail: [email protected]

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Faster dihydrogen catalysis is observed when the steric pressure at the iridium center is decreased. Thus, starting from 3, having a 2,6-Me2C6H3 substituent at the amido nitrogen atom in place of the bulkier 2,6-Pri2C6H3, a concentration of ca. 7 mol % of H2 led to an equilibrium mixture of 4:3 with no detectable variation in the equilibrium constant (Keq = 4) in a reaction characterized by a half-life, t½, of ca. 5 min. However, in the presence of an excess of dihydrogen, complexes 1 and 3 abruptly react with H2 to yield a known dinuclear trihydride [1] along with an equimolecular mixture of the free and protonated aminopyridine, HAp and [H2Ap]BArF, respectively.

Poster Sessions The conversions of protons to hydrogen and carbon dioxide to C1 chemical feedstocks have garnered heavy interest in the search for sustainable alternative fuels. In this presentation, we will describe new molecular motifs for the electrocatalytic conversion of protons and carbon dioxide to hydrogen and carbon monoxide, respectively. A highvalent molybdenum(IV)-oxo complex supported by the pentadentate ligand PY5Me2 can be reduced to catalyze hydrogen evolution in aqueous and acidic organic solutions at moderate overpotentials and high Faradaic efficiencies. In addition, a series of nickel complexes supported by tetradentate pyridine ligands has been explored for the electrocatalytic reduction of carbon dioxide with high selectivity over proton reduction. Structure-activity relationships in the context of judicious ligand design for each process will be presented. Keywords: electrocatalysis, carbon dioxide, proton reduction

MS.C2.P.352 New Cobalt (II) and Nickel (II) catalysts for alkane hydroxylation Elisa Tordina, Uwe Monkowiusa, Siegfried Schindlerb, and Günther Knöra a Institute of Inorganic Chemistry, Johannes Kepler University, Linz (Austria ) b Institute for Inorganic and Analytical Chemistry, Justus Liebig University, Gießen (Germany). E-mail: [email protected] The hydroxylation of saturated hydrocarbons is an important, but still very difficult, chemical transformation and the development of efficient catalysts for the selective oxygenation of alkanes has been subjected to a lot of interest from both the synthetic and industrial organic chemistry point of view [1]. Moreover, low molecular weight coordination compounds have been used to functionally model different types of enzymes [2] and, in this context, we decide to focus our attention on the tetradendate tripodal ligands tris[2-(dimethylamino)ethyl]amine (L1) and (2-aminoethyl) bis(2-pyridylmethyl) amine (L2). The compounds [Co(L1)(CH3COO)] [PF6], [Ni(L1)(CH3COO)][PF6] and [Ni(L2)(CH3COO)][PF6] were successfully prepared by reaction between a methanol solution of bis acetato cobalt (II) or nickel (II) and L1 or L2 in equimolar amounts followed by anion metathesis reaction between the non-coordinated acetate group and an hexafluorophosphate anion. These three new compounds showed catalytic activity toward the oxidation of cyclohexane to cyclohexanol with m-chloroperbenzoic acid as a sacrificial oxidative agent in a mixture of CH3CN/CH2Cl2 (3/1 v/v) [1c]. In particular, a TON of 235 has been measured for the compound [Co(L1)(CH3COO)][PF6] while for the nickel complexes [Ni(L1)(CH3COO)][PF6] and [Ni(L2)(CH3COO)][PF6], TONs of 7 and 135 respectively were obtained.

MS.C2.P.353 Quantum Molecular Spintronics Based on Single-Molecule Magnets Masahiro Yamashita. Department of Chemistry, Tohoku University, Sendai, Japan. E-mail: [email protected] Spintronics is a key technology in 21st century based on the freedoms of the charge, spin, as well as orbital of the electron. The MRAM systems (magnetic random access memory) by using GMR, CMR or TMR have several advantages such as no volatility of information, the high operation speed of nanoseconds, the high information memory storage density, and the low consuming electric power. Usually in these systems, the bulk magnets composed of the transition metal ions or conventional magnets are used, while in our study we will use Single-Molecule Quantum Magnets (SMMs), which are composed of multi-nuclear metal complexes and nano-size magnets. Moreover, SMMs show the slow magnetic relaxations with the double-well potential defined as |D|S2 and the quantum tunneling. Although the bulk magnets are used in conventional spintronics with the largest spin quantum number of 5/2 for example, we can create the artificial spin quantum numbers of 10, 20, 30, etc. in SMMs. Then, we can realize the new quantum molecular spintronics by using SMMs. According to such a strategy, we have synthesized the conducting SMM such as [Pc2Tb]Cl0.6, whose blocking temperature is 47K. The hysteresis is observed below 10K. This conducting SMM shows the negative magnetoresistance below 8 K. As for the second strategy, we have a plane of the input and output of one memory in double-decker Tb(III) SMM (Pc2Tb) by using the spin polarized STM (Scanning Tunneling Microscopy). In this research, we have observed Kondo Effect at 4.8 K by using STS (Scanning Tunneling Spectroscopy) for the first time. We have succeeded in controlling the appearance and disappearance of Kondo Peak by the electron injection using STS, reversibly. This is considered as the first single-molecule memory device.[1] As for the third strategy, we have made the FET (Field Effect Transistor) devices of SMMs. The Pc2Dy device shows the ambipolar (n- and p-type) behavior, while the Pc2Tb device shows the p-type behavior. Such a difference is explained by the energy levels of the lanthanide ions.[2] [1] T. Komeda, M. Yamashita, et al., Nature Commun., 2, 217(2011).

Molecular Spintronics, Single-Molecule Magnets, Kondo Effect

MS.C2.P.354 Convenient Synthesis of Aryl Silanes by Palladium-Catalyzed Arylation of Hydrosilanes Yoshinori Yamanoi,a Hiroshi Nishihara,a aDepartment of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan). E-mail: [email protected]

[1] a) T. Nagataki, y. Tachi, S. Itoh, Chem. Comm., 2006, 4016-4018; b) T. Nagataki, K. Ishii, Y. Tachi, S. Itoh, Dalton Trans., 2007, 1120-1128; c) M. Balamurugan, R. Mayilmurugan, E. Suresh, M. Palaniandavar, Dalton Trans, 2011, 40, 9413-9424. [2] a) T. Nebe, J. Yuan Xu, A. Beitat, C. Würtele, O. Walter, M. Serafin, S. Schindler, Inorg. Chim. Acta, 2010, 2965-2970; b) A.L. Feig, S.J. Lippard, Chem. Rev., 1994, 94, 759; c) M. Costas, M.P. Mehn, M.P. Jensen, L. Que, Chem. Rev., 2004, 104, 939; d) S.V. Kryatov, E.V. RybakAkimova, S. Schindler, Chem. Rev., 2005, 105, 2175.

Keywords: hydroxylation, cobalt, nickel

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Aryl silanes are one of the most fundamental and widespread intermediates in modern organic chemistry, and many preparation methods have been proposed. One of the great strengths and sources of creativity in synthetic chemistry is the availability of viable routes to the same or similar chemical products. On the basis of this idea, much interest has been focused on the development of a methodology for the introduction of silicon into organic molecules, because such a methodology would be valuable for the synthesis of novel siliconcontaining materials or pharmaceuticals. The traditional method of preparing aryl silanes is the reaction

Poster Sessions of chlorosilanes with aryl organometallic reagents. Although these protocols lack wide applicability, an efficient synthesis of functionally substituted aryl silanes has been elusive. Recently, a transition metal-catalyzed silyl group transfer to aryl halides has been developed in our group. In the presence of transition metal catalyst and base, various kinds of aryl iodides were coupled with hydrosilanes to give the corresponding arylated products in high yields. Keywords: palladium, hydrosilane, arylation

MS.C2.P.355 Synthesis and Catalytic Activity of Lanthanide Aminophenolate Complexes Yingming Yao, Jie Zhang, Yong Zhang, Qi Shen, College of Chemistry, Chemical Engineering & Materials Science, Dushu Lake Campus, Soochow University, Suzhou, (China). E-mail: [email protected] The aminophenoxy group is a type of dianionic N,O-chelate ligand, which combines the properties of oxygen- and nitrogen-based ligands. These ligand systems have been utilized in main group and transitionmetal coordination chemistry, and some of these metal complexes show good activity in homogeneous catalysis [1]. The utilization of such ligands in organolanthanide chemistry, however, has not been studied to any significant degree [2]. Recently, we reported the first examples of lanthanide metal amides bearing dianionic aminophenoxy ligands synthesized from aminophenol starting materials via amine elimination reaction, and found that these aminophenoxy lanthanide metal complexes could initiate the ring-opening polymerization of lactide [3]. Here we reported the synthesis of a series of lanthanide derivatives stabilized by aminophenoxy ligand via salt metathesis reaction. Reactions of lithium aminophenolate with anhydrous LnCl3 in a 1:1 molar ration in THF, after workup, gave the lanthanide aminophenoxy chloride LLnCl(THF) in good isolated yields, which are useful precursors for the synthesis of a series of lanthanide aminophenolate derivatives as shown in Scheme 1. It was found that some of the lanthanide guanidinate complexes are efficient initiators for L-lactide polymerization, whereas the aryloxo complexes are inert.

[1] A. F. Douglas, B. O. Patrick, P. Mehrkhodavandi, Angew. Chem. Int. Ed. 2008, 47, 2290-2293. [2] D. W. Qin, F. B. Han, Y. M. Yao, Y. Zhang, Q. Shen, Dalton Trans. 2009, 5535-5541. [3] M. Lu, Y. M. Yao, Y. Zhang, Q. Shen, Dalton Trans. 2010, 39, 9530-9537.

Keywords: lanthanide complex, synthesis, homogeneous catalysis

MS.C2.P.356 Highly Active Oligomeric (Salen)VO Catalyst for Oxygenation of Sulfides Maryam Zare, Mojtaba Bagherzadeh, Department of Chemistry, Sharif University of Technology, Tehran (Iran), E-mail: [email protected]. edu Vanadium complexes modeling the active center of vanadatedependent haloperoxidases have been extensively studied due to their biological relevance and catalytic properties. Many Schiff base complexes of vanadium are employed in sulfoxidation reaction in the homogeneous phase, but there is one serious problem including the difficulty in separation and recycling of the expensive catalysts, as well as leaching of the active metal into the solvent and the insufficient stability of the catalyst. To avoid this problem, considerable attention has been paid to the heterogeneous catalytic process by different approaches. An attractive approach to these problems involves incorporation of metals into polymers. Herein, Oligomeric ligand was synthesized by condensation of ethylendiamine with 5, 5’-(piperazine-1, 4-diylbis (methylene))bis-(2-hydroxybenzaldehyde). V(IV)-complex was synthesized by the reaction of corresponding oligomeric ligand with VO (acac)2 under refluxing condition in air atmosphere in mixture of MeOH and dichloromethane for 12h.The compound were characterized by elemental analysis, IR, UV/Vis, and 1H NMR spectroscopies. This oligomer catalyzes efficiently the oxidation of sulfide in high yields by urea hydrogen peroxide (UHP) in mixture CH3OH/CH2Cl2 at room tempature. The oxidation of various sulfides was carried out with this system. The results showed that yields of oxidation of sulfides clearly depend on the influence of steric and electronic properties of sulfides. In this system, the highest and lowest yields are obtained for methyl phenyl sulfide and diphenyl sulphide, respectively. The catalyst can be recycled without considerable loss of activity. IR spectra data of both freshly prepared and recovered catalysts indicate that the metal complex moiety is intact during the catalytic reaction. [1] J.M. Ready, E.N. Jacobsen, J. Am. Chem. Soc, 2001, 123, 2687-2688. [2] R.I. Kureshy, N.H. Khan, S.H.R. Abdi, S. Singh, I. Ahmad, R.V. Jasra, A.P. Vyas, J. Catal, 2004, 224, 229–235. [3] N. Nishat, S. Ahmad khan,S. Parveen, R. Rasool, J. Coord. Chem, 2010, 63, 3944–3955.

MS.C3.P.357

Scheme 1. Synthesis of lanthanide aminophenolate complexes.

We are grateful to the National Natural Science Foundation of China (Grants 20972108, 21174095, and 21132002) for financial support.

Cobalt(II) Complexes with Unsymmetric Tridentate HydrazoneBased Ligands Saeko Akiyama,a Takayoshi Suzuki,a Yukinari Sunatsuki,a Masaaki Kojima,a Kiyohiko Nakajima,b aGraduate School of Natural Science and Technology, Okayama University, Okayama (Japan). bDepartment of Chemistry, Aichi University of Education, Kariya (Japan). E-mail: [email protected] Spin-crossover (SCO) phenomenon is one of the most fascinating examples of molecular bistability which is interested in the development of molecular memories and switches. Iron(II) SCO

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Keywords: heterogeneous catalytic process, vanadium, sulfides

Poster Sessions complexes have been extensively investigated; however, only a limited number of cobalt(II) SCO complexes were known to date. In general, the cobalt(II) SCO complex requires a stronger ligand-field than the corresponding Fe(II) SCO complexes. We have designed new unsymmetric tridentate hydrazone-based ligands (Figs. 1 and 2) which were obtained by a 1:1 reaction of 2-pyridylhydrazine and 4-formylimidazoles or 2-(diphenylphos-phino)benzaldehyde. These ligands have an ability to control their ligand-field strengths by deprotonation of the N-H proton on the hydrazone or the imidazole group and by introduction of substituent groups on the pyridine or imidazole rings. With these unsymmetrical tridentate ligands, H2LR,R’ and HLp, we have succeeded to prepare cobalt(II) complexes, [Co(H2LR,R’)2] X2 (X = Cl, BPh4) and [Co(HLp)2]Cl2 [H2LR,R’ = (1H-imidazole-4carbaldehyde)-2-pyridylhydrazones; HLp = 2-(diphenylphosphino) benzaldehyde-2-pyridylhydrazone]. The X-ray diffraction studies revealed that all complexes have a meridional configuration due to the high planarity of the ligands. The magnetic measurements indicated that [Co(H2LR,R’)2]X2 were in the high-spin states by at the temperature range of 5−300 K. Introduction of electron-donating alkyl groups to the imidazole ring showed almost no effect on the magnetic properties of the cobalt(II) complexes. On the other hand, [Co(HLp)2]Cl2 was in the low-spin state at the whole temperature range. We expect that deprotonation from HLR,R’ would give a stronger ligand-field than the fully protonated form, and then cobalt(II) complexes, [Co(HLR,R’)2] or [Co(LR,R’)2]2-, may exhibit SCO behavior. The study is now in progress along this line.

results provide strong evidence on the existence of a dissociative process involving PPh3, although competitive pathways involving the coordinated hydride cannot be completely ruled out. Thus, the energy barrier calculated for PPh3 dissociation is of 33.5 kcal mol-1 in the singlet state, is in agreement with the experimental observation of very slow substitution under thermal conditions. However, the energy barrier in the excited triplet state is of only 3.0 kcal mol-1, which indicates that phosphine dissociation is easily achievable under photochemical conditions. Financial support by the Spanish MICINN (Proyecto CTQ200914443-C02-01) and Junta de Andalucía (Proyecto P07-FQM-02734) is gratefully acknowledged.

Keywords: Photochemistry, DFT calculations, hydride ligands

MS.C3.P.359 Oxygen-Atom Transfer with Metal-Arylnitroso Complexes Mohammad S. Askari, Xavier Ottenwaelder,* Department of Chemistry and Biochemistry, Concordia University, Montreal (Canada). E-mail: [email protected]

Keywords: hydrazones, spin-crossover, cobalt(II) complexes

MS.C3.P.358 Photochemical studies on the [CpRuH(PPh3)2] hydride complex Algarra Andrés G., Pino-Chamorro José A., Basallote Manuel G., Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica s/n, Facultad de Ciencias, Universidad de Cádiz, Polígono Universitario Río San Pedro, Puerto Real, 11510 Cádiz (Spain). E-mail: [email protected] Laser flash photolysis studies in the nanosecond time scale show the existence of a photochemical process upon irradiation at 355 nm of solutions containing the [CpRuH(PPh3)2] complex. However, NMR and ESI-MS analysis of the photolyzed samples do not show any significant change with respect to the starting complex, thus indicating the reversibility of the process. The species detected a few nanoseconds after irradiation shows a spectrum with bands at ca 435and/or 625 nm, which disappear in a first order process with a rate constant in the order of 107 s-1. DFT and TD-DFT studies have been carried out to understand the nature of the photochemical processes taking place. The theoretical

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Deoxygenation of an arylnitroso species (Ar-N=O) can lead formally to a 6-electron nitrene, which is a key intermediate in amination and aziridination reactions. When coordinated to a transition metal, this moiety can form imido bonding (M=NR) or nitrenoid species (M-NR) depending on the occupancy of the d orbitals of pi symmetry. This, in turn, is controlled by the nature of the metal ion and its coordination number, with mid-group transition elements having a borderline behaviour with respect to the M-N bonding. In our effort to study the transformation and reactivity of nitrogencontaining functional groups in the vicinity of a transition metal, we here report the synthesis of a ligand, LNHOH, bearing a pendant hydroxylamine group. Coordination of LNHOH with iron(II) salts results in the disproportionation of the hydroxylamine group and formation of the nitroso [LNOFe(OAc)] and amine [LNH2Fe(OAc)] complexes. Reaction of the nitroso complex with a tertiary phosphine (R3P) entails the transfer of the oxygen atom to the phosphine, yielding R3PO, together with the formation of the iron-iminophosphorane complex (M-N=PR3). This result suggests involvement of a reactive iron-nitrenoid species. In addition, oxygen-atom transfer to the amine complex using various oxidants yields the corresponding nitroso and/ or nitro complexes. Kinetic studies of these reactions and possible mechanistic pathways and intermediates will be presented.

Poster Sessions

Keywords: oxygen-atom transfer, nitroso, nitrene

[1] N. Carmona, E. Herrero-Hernandez, J. Llopis, M.A. Villegas, J. Sol-Gel Sci. Technol., 2008, 47, 31-37. [2] C. Zhu, H. Xu, Prog. Chem., 2001, 4, 261-267

MS.C3.P.361

Keywords: thermochromism, cobalt complexes, stereochemistry effect

The colours of several metal complexes can be changed when they are heated to a certain temperature. This reversible or irreversible colour change with temperature is known as thermochromism. The thermochromic coordination complexes are one of the interesting classes of compounds that present various practical applications as temperature indicator devices or imaging systems [1]. From the study of thermochromic colour changes of various metal complexes in solution it has been observed that their thermal properties are mainly influenced by structural changes in the coordination sphere [2]. The present study has a aim of investigating the influence of inorganic ligands position on change temperature in two octahedral cobalt(II) complexes, trans‑[CoCl2(PiTn)2] (PiTn = 2-(1-pyrazolyl)2-thiazoline) and cis‑[CoCl(H2O)(DMPiTn)2]Cl (DMPiTn = 2-(3,5-dimethyl-1‑pyrazolyl)-2-thiazoline).

MS.C3.P.362 Structural Investigation of Anion-Triazole Interactions: A theoretical approach Antonio Bauzá, Pere M. Deyà, Antonio Frontera*, Departament de Química, Universitat de les Illes Balears, 07122 Palma de Mallorca. E-mail: [email protected] Non covalent interactions are crucial in many areas of modern chemistry, particulary in the field of supramolecular chemistry and molecular recognition [1]. Interactions involving aromatic rings play a key role in chemical and biological processes [2]. Those interactions are also critical in solid state chemistry, due to their importance in fields like crystal engineering, nanomaterials, among others [3]. Recently, Brooker et al have synthesized and characterized a series of eight mononuclear nickel (II) complexes using two ligands based on the triazole moiety (4-amino-3,5-di(2-pyridyl)-1,2,4-triazole (adpt) and 4-pyrrolyl-3,5-di(2-pyridyl)-1,2,4-triazole (pldpt)) where ClO4–, BF4–, PF6– and SbF6– act as counterions [4]. The complex of pldpt and nickel(II) presents interesting anion–π interactions in the solid state. One type is referred to the interaction of the anion with only one triazole ring, while the other one is referred to an anion placed in a “π pocket” interacting with two triazole rings and one pyridine ring. Herein, we report a high level DFT study (BP86-D/ def2-TZVP level of theory) of the energetic and geometric features of the interactions (see figure). Apart from the anion-π interactions, other important non covalent forces are involved in the anion binding. We have proposed several models in order to evaluate different contributions (purely electrostatic, H-bonding and anion-π) to the total binding energy.

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Effect of Stereochemistry on Thermochromism of Two Octahedral Co(II) Complexes F. J. Barros-Garcíaa, R. Pedrero-Marína, F. Luna-Gilesa, A. BernalteGarcíaa, E. Viñuelas-Zahínosa, P. Torres-Garcíaa. aDepartment of Organic and Inorganic Chemistry, University of Extremadura, Badajoz, (Spain). E-mail: [email protected]

Poster Sessions of the cage complexes as molecular scaffolds allows for both their functionalization with different pendants and the immobilization on a working electrode. The rational design of such immobilized cage electrocatalysts undoubtedly will allow obtaining those with the lowest overpotential. This study was supported by RFBR (grant 12-03-00961) and RAS (program 7).

[1] C. A. Hunter and J. K. M. Sanders, J. Am. Chem. Soc., 1990, 112, 55255534. [2] E. A. Meyer, R. K. Castellano and F. Diederich, Angew. Chem., Int. Ed., 2003, 42, 1210-1250. [3] P. Metrangolo, H. Neukirch, T. Pilati and G. Resnati, Acc. Chem. Res., 2005, 38, 386–395. [4] N. G. White, J. A. Kitchen and S. Brooker, Eur. J. Inorg. Chem., 2009, 1172-1180.

Keywords: Anion-π interaction, π-pocket, DFT-study

[1] Y.Z. Voloshin et al., Chem. Commun., 2011, 47, 7737–7739. [2] Y.Z. Voloshin et al., Dalton Trans., 2012, DOI:10.1039/C2DT12513G.

MS.C3.P.364

Keywords: hydrogen clathrochelates

Electropolymerized Thiophene-Containing Cobalt Clathrochelates for H2 Evolution Alexander Belov, Alexander Dolganov, Valentin Novikov, Yan Voloshin, Yurii Bubnov. Nesmeyanov Institute of Organoelement Compounds RAS, Moscow (Russia). E-mail: [email protected]

MS.C3.P.365

The search for the catalysts that would allow facilitating the H+ reduction to H2 using cheap and earth-abundant materials is now of interest. Despite the recent advances in this field, the design of efficient electrocatalysts with minimal overpotentials and long-term stability in aqueous solutions is a still real challenge. Recently, the electrocatalytic activity of the boron-capped ribbed-functionalized cobalt clathrochelates (including those that we chemically immobilized on a working electrode) in hydrogen-producing systems has been reported [1,2]. In contrast to the apical substituents in the capping (cross-linking) fragments of an encapsulating macrobicyclic ligand, them ribbed substituents strongly affect both the geometry and the electronic structure of the cage complexes. This type of a functionalization allowed obtaining the efficient electrocatalysts of the 2H+/H2 reaction without overpotential by fine tuning the Co2+/+ redox potential couple to that of this redox process [1]. At the same time, the chemically and redox-active apical substituents make it possible to immobilize the clathrochelate electrocatalysts on a surface of the working electrode or in the polymer matrix. The apically functionalized thiophene-containing cobalt(II) clathrochelates were obtained by a direct template condensation of the three corresponding a-dioxime molecules with the thiophene-2boronic acid on the Co2+ ion matrix (Scheme). The complexes obtained were characterized using elemental analysis, MALDI-TOF mass spectrometry, IR, UV-Vis, 1H and 13C{1H} NMR spectroscopies and by X-ray diffraction (in the case of the tris-a-benzyldioximate cobalt(II) clathrochelate, see Scheme). The cyclic voltammograms (CVs) of the solutions of the cobalt complexes in acetonitrile contain two oxidation waves in the anodic range. First one at appr. 500 mV is a one-electron and reversible process assigned to the redox couple Co2+/3+. The second wave at appr. 900 mV is irreversible and corresponds to the oxidation of the thiophene fragments resulting in the formation of the cation-radicals that undergo a fast dimerization reaction. The polymer product of this reaction precipitated on an electrode surface turned out to be the efficient catalyst for H2 evolution. The specific reactivity

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electropolymerization,

Halo- and Hybrid Stibines and Bismuthines: Coordination and Hypervalency Sophie Benjamin, William Levason, Gillian Reid, Michael Rogers, and Robert Warr. School of Chemistry, University of Southampton, Southampton (UK). E-mail: [email protected] The coordination chemistry of stibines (SbR3) and bismuthines (BiR3) with transition metals is well established, and can be compared to that of phosphines, with certain key differences [1]. One such is the phenomenon of hypervalent interactions at the Sb or Bi centre, which are of interest in modifying catalytic properties [2]. Conversely, trihalostibines (SbX3) are known to behave as Lewis acids towards neutral ligands. Alkylhalostibines and -bismuthines ERnX(3-n) (E = Sb, Bi; X = Cl, Br; R = alkyl; n = 1, 2) are used as reagents in the synthesis of asymmetric organostibines and –bismuthines, but the coordination chemistry of these species themselves has been very little investigated. Unusually, they are Lewis amphoteric, having the potential to act both as donors and as acceptors. We have shown that EMeX2 form adducts with neutral O and N donor ligands, containing five-coordinate, pseudo square pyramidal Sb or Bi centres. Attempts to form similar adducts with EMe2X result in the corresponding EMeX2 adducts, arising from disproportionation. SbMe2Br forms complexes with several transition metal carbonyl fragments, including 1:1 adducts with Mn(I), Fe(II) and M(0) (M = Cr, Mo, W) and the 1:3 adduct [Mn(CO)3(SbMe2Br)3][CF3SO3]. Several of these complexes contain short hypervalent contacts between the relatively electron deficient Sb centre and heteroatoms from the anion. In such cases Sb can be seen to be acting as a donor and an acceptor simultaneously. SbMeBr2 forms 1:1 adducts with Group 6 pentacarbonyls, whereas reaction of BiMe2Br with [W(CO)5(THF)] (THF = tetrahydrofuran) results in formation of [W(CO)5(BiMe3)], once again a result of disproportionation. Hypervalent contacts to a coordinated Sb or Bi centre are also apparent in several complexes of hybrid ligands containing the donor sets E2O, E2S and E2N. These rare distibines and dibismuthines have been synthesised and complexed to transition metals demonstrating

Poster Sessions a variety of binding modes. In cases where only the Sb or Bi atoms are coordinated (either in bidentate bridging or bidentate chelating modes), the central heteroatom within the ligand backbone approaches one or both Sb or Bi atoms to form a contact well within the sum of the Van der Waals radii (figure). Such ligands can also form complexes in which all three donors coordinate in a fac-tridentate manner. The potentially tetradentate hybrid tristibine N(CH2-2-C5H4SbMe2)3 has now been synthesised and its coordination chemistry is under investigation.

[1] L. J. Baird, C. A. Black, A. G. Blackman, Polyhedron, 2007, 26, 378–384. [2] N. A. Hall, C. Duboc, M-N. Collomb, A. Deronzier, A. G. Blackman, Dalton Trans., 2011, 40, 12075-12082.

Keywords: Ligand design, hexadentate, multinuclear

MS.C3.P.367

Keywords: Stibine, Bismuthine, Hypervalency

MS.C3.P.366 Control of Metal Complex Nuclearity Through Ligand Design Allan G. Blackman,a Nikita A. Hall,a, Department of Chemistry, University of Otago, Dunedin, (New Zealand). E-mail: blackman@ chemistry.otago.ac.nz The rational synthesis of metal complexes having specific geometries and nuclearities can be achieved through judicious design of appropriate ligands. This can give a large degree of control over the magnetic, spectral, electrochemical and structural properties of the resulting transition metal complexes, and such design can also allow the reactivity of the complexes to be tuned. Increasing attention is being paid to the design of multidentate ligands capable of binding more than one metal ion. Acyclic multidentate ligands with multiple binding domains separated by rigid spacers that do not permit coordination of all donor atoms to a single metal ion have successfully been used in the controlled synthesis of complexes containing two or more metal ions. However, flexible multidentate acyclic ligands containing alkyl chains have been somewhat less explored with respect to the rational synthesis of multinuclear metal complexes, owing to the perceived lack of control over both the nuclearity and isomeric possibilities of the resulting complexes that such flexibility provides. We have prepared a family of potentially hexadentate ligands containing both 2,2’-bipyridine (bipy) and aliphatic amine donors (see figure below) with the aim of controlling the nuclearities of the resulting metal complexes [1], [2]. The ligands comprise two tridentate binding domains separated by a flexible aliphatic carbon chain spacer, the length of which can be varied. We will present our results for a variety of metal ions (M = Mn2+, Fe2+, Co3+, Ni2+, Cu2+, Zn2+) and aliphatic chain lengths (n = 2, 3, 4, 5, 8). For n = 2 and 3, exclusive formation of mononuclear complexes in a single isomeric form is observed. However, as the spacer length is increased, di- and trinuclear complexes predominate, owing to the inability of a single metal ion to accommodate a large aliphatic chelate ring.

The coupling of electron and proton transfers is currently attracting much interest owing to the recognition that it can avoid high-energy intermediates and the fact that electrostatic charge builds up in biological or chemical processes [1], [2]. Most of the studies of protoncoupled electron transfer (PCET) on dinuclear complexes have focused on Ru/Os or Mn2 complexes involving (de)protonable bridging ligand with the metal pair accepting or releasing electrons. A single example of a pH-induced reversible intramolecular electron transfer within a dinuclear complex has been previously reported [3]. We will present here a diiron mixed-valent complex bearing a terminal aminobenzyl ligand that can be reversibly deprotonated, the deprotonation inducing an intramolecular electron transfer. Complex 1 [(LBnNH2)FeIII(µ-mpdp)FeII]2+ (mpdp2– = m-phenylenedipropionate) presents the triply bridged core [FeIII(µOPh)(µ-mpdp)FeII(NH2-Bn)]2+. Upon reaction with triethylamine, the terminal aniline ligand coordinated to the FeII is converted to anilinate. The resulting complex 2 with the [FeII(µ-OPh)(µ-mpdp)FeIII(NH-Bn)]+ core features an inversion of the iron valences. This observation is supported by a combination of UV-visible, 1H NMR, and Mössbauer spectroscopic studies. Addition of perchloric acid on an acetonitrile solution of 2 gives back complex 1 [4]. Electrochemical investigations have been performed to disentangle this proton induced intervalence charge transfer [5]. It was first demonstrated that in a buffered +HNEt3/NEt3 acetonitrile solution, both mixed-valent systems 1 and 2 coexist while the oxidized and reduced complexes exist as single forms, namely the deprotonated diferric complex [(LBnNH)FeIII(µ-mpdp)FeIII]2+ and the protonated diferrous species [(LBnNH2)FeII(µ-mpdp)FeII]+, respectively. The spontaneous conversion between complexes 1 and 2 was thus investigated by the in situ generation of complex 2 and the monitoring of the reduction of complex 1. Substituting triethylamine by pyrrolidine allows modifying both the driving force and the kinetics of the reaction between the two mixed-valent systems. The observed variations evidence that the intervalence charge transfer is indeed concerted with the proton transfer. This conclusion was further confirmed by the determination of the H/D isotope effect.

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[1] W. Levason and G. Reid, Coord. Chem. Rev., 2006, 250, 2565-2594. [2] N. Kakusawa, Y. Tobiyasu, S. Yasuike, K. Yamaguchi, H. Seki, and J. Kurita, J.Organomet.Chem., 2006, 691, 2953-2968.

Concerted Proton-Coupled Valence Inversion in Mixed-Valent Diiron Complexes Geneviève Blondin,a Michaël Carboni,a Ramachandran Balasubramanian,a Jean-Marc Latour,a Juan Carlos Canales,b Cyrille Costentin,b Marc Robert,b Jean-Michel Savéant,b aiRTSV/LCBM/pmb, UMR 5249 CNRS-UJF-CEA, Grenoble, (France). bLEM, UMR 7591 CNRS-Université Paris-Diderot, Paris (France). E-mail: genevieve. [email protected]

Poster Sessions [1] M. H. V. Huynh, T. J. Meyer, Chem. Rev., 2007, 107, 5004-5064. [2] C. Costentin, M. Robert, J.-M. Savéant, Chem. Rev., 2010, 110, PR1-PR40. [3] G. A. Neyhart, T. J. Meyer, Inorg. Chem., 1986, 25, 4807-4808. [4] E. Gouré, G. Thiabaud, M. Carboni, N. Gon, P. Dubourdeaux, R. Garcia-Serres, M. Clémancey, J.-L. Oddou, A. Y. Robin, L. Jacquamet, L. Dubois, G. Blondin, J.-M. Latour, Inorg. Chem., 2011, 50, 6408-6410. [5] R. Balasubramanian, G. Blondin, J. C. Canales, C. Costentin, J.-M. Latour, M. Robert, J.-M. Savéant, J.Am. Chem.Soc., 2012, 134, 1906-1909.

Keywords: Mixed-valent complexes, Proton-coupled electron transfer, Diiron complexes

not only for studying the effects of ion pairing and the possible cooperative binding, but also for their potencial application in fields such as salt solubilization, transport through membranes, and extraction.[1] Bearing this idea in mind, we have designed and prepared the heteroditopic receptors L1, L2, L3 and L4, which contain an urea group as hydrogen donor unit for anion recognition and an acyclic or a macrocyclic moiety for accommodating the metal ion (Fig. 1). The mutual location of these two compartments is expected to produce cooperative effects of electrostatic and/or conformational nature in selective metal salt recognition.

MS.C3.P.369 Development of Highly Emissive Europium(III) Complexes as Optical Probes of the Cellular Environment Stephen J. Butlera and David Parkera, aDepartment of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK. E-mail: [email protected]; [email protected] Non-invasive probes which report on the structure and function of a cell are required in order to enhance our understanding of fundamental cellular processes. At present, much remains to be understood about how to selectively monitor biological substrates in a cellular environment. Ideally, an optical probe should efficiently absorb and emit light and provide a strong luminescent signal upon binding a target analyte. In addition, the probe must exhibit good photostability and solubility in the chosen cellular incubation medium.[1] This work focuses on the development of highly sensitive luminescent complexes which address these issues, resulting in probes capable of signalling the concentration and distribution of essential species in cell compartments, using fluorescence spectroscopy and microscopy. A series of europium(III) complexes of varying charge, hydrophilicity, and peripheral structure has been prepared and characterised. Each complex is based on a 1,4,7-triazacyclononane ring with three appended pyridyl phosphinate groups, functionalised with aryl-substituted alkynyl sensitising moieties. We demonstrate the ability of these complexes to efficiently absorb light with high molar extinction coefficients (approx. 60,000 M-1 cm-1), and effectively transfer the chromophore excited state energy to the Eu3+ metal centre, resulting in overall emission quantum yields of over 50%. Structural modifications of the pyridylalknyl chromophore allowed for rational control over physical properties such as water solubility, as well as the optical response. The ability of this new class of compounds to bind important bioactive species selectively under simulated ‘physiological’ conditions has been assessed, validating their potential to monitor specific biological processes with high sensitivity within a cell.

Fig. 1. Selected heteroditopic receptors

Solvent extraction experiments have been carried out in order to investigate the capability of L1 and L2 to extract different Cu(II) salts. These studies pointed to an important selectivity of L2 for sulphate over chloride when Cu(II) ion is present. Thus, the selectivity towards sulphate can be modulated changing the nature of the cation binding site while keeping in close contact the two recognition compartments to promote a cooperative interaction. The crystal structures of the neutral Cu(II) sulphate complexes with L3 and L4 confirm the formation of ion pairs and a cooperative effect thanks to: i) hydrogen-bonding interaction between the urea group and the anion, and ii) coordination of the anion to the metal ion through an available binding site (Fig. 2). The solid state structures are in agreement with the non-electrolyte behaviour observed in solution for these complexes, which results in an efficient metal salt extraction in chloroform. In the case of chloride, only the acyclic receptor L1 is able to extract the ion pair neutral complex into the organic phase, while no metal salt extraction is observed with the macrocyclic receptor L2 due to the formation of a 1:1 electrolyte complex.

[1] E. J. New, D. Parker, D. G. Smith, J. W. Walton, Curr. Opin. Chem. Biol. 2010, 14, 238-246.

Keywords: Coordination Chemistry, Luminescence, Imaging

MS.C3.P.370 Ditopic Ligands for Anion Recognition Through Cooperative Binding Israel Carreira-Barral,a Andrés de Blas,a David Esteban-Gómez,a Carlos Platas-Iglesias,a Teresa Rodríguez-Blas.a aDepartment of Fundamental Chemistry, University of A Coruña, A Coruña (Spain). E-mail: [email protected] The design of ion pair receptors containing sites for simultaneous complexation of a cation and an anion is a promising area of research,

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Fig. 2. Selective anion recognition by cooperative binding of the urea group and the metal ion in the [CuL4(SO4)] complex [1] S. K. Kim, J. L. Sessler, Chem. Soc. Rev., 2010, 39, 3784-3809.

Keywords: ion pair, solvent extraction, anion recognition

Poster Sessions

Molybdenum and Iron complexes of chelating amino-thiophenol ligands with sterically protecting ortho-substituents Ivan Castillo,a Alexander Mondragón,a aInstituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, CU 04360, México DF (Mexico). E-mail: [email protected] Sulfur- and nitrogen-based donors are present in the active sites of numerous metalloenzymes as part of organic (methionine, cysteine, histidine) or inorganic (sulfido) ligands. One of the most remarkable examples is the FeMo cofactor of nitrogenase, in which sulfido donors provide a C3-symmetric environment for both molybdenum and iron [1], the latter being coordinatively unsaturated. Despite significant advances in dinitrogen activation with bioinspired Mo [2] and Fe systems [3], biologically relevant sulfur-based donors are missing from the transition metal-N2 activation map, likely due to the difficulties inherent to the development of sterically hindered thiolates for coordinatively unsaturated metal complexes [4]. We have developed novel thiophenol-based ligands with bulky ortho-substituents to provide steric protection at the metal-binding pocket; the fluorinated groups at the ortho-position both prevent arenemetal interactions, and facilitate their preparation from phenols in the key thermal rearrangement step [5]. The ligands in Scheme 1 have allowed us to prepare Mo and Fe(III) complexes with a C3 coordination environment ideally suited for N2-reactivity studies.

[1] O. Einsle, F. A. Tezcan, S. L. A. Andrade, B. Schmid, M. Yoshida, J. B. Howard, D. C. Rees, Science 2002, 297, 1696-1700. [2] D. V. Yandulov, R. R. Shcrock, Science 2003, 301, 6252-6253. [3] Y. Lee, N. P. Mankad, J. C. Peters, Nature Chem. 2010, 2, 558-565. [4] B. S. Buyuktas, P. P. Power, Chem. Commun. 1998, 1689-1690. [5] A. Mondragón, I. Monsalvo, I. Regla, I. Castillo, Tetrahedron Lett. 2010, 51, 767-770.

Keywords: nitrogenase, thiophenols, molybdenum

MS.C3.P.372 Luminescence and EPR of Benzimidazolic Lanthanides Complexes Silvia E. Castillo-Blum,a Daniela Olea-Román,a George Pistolis,b Athinoula L. Petrou,c Martha E. Sosa-Torres,a Alejandro SolanoPeralta,a aFacultad de Química, Universidad Nacional Autónoma de México, México D. F. (México). bInstitute of Physical Chemistry, NCSR “Demokritos”, Attiki (Greece). cDepartment of Chemistry,

National and Kapodistrian University of Athens, Athens (Greece). E-mail: [email protected] Lanthanides anhydrous salts show important luminescent properties that allow them to be used as solid materials in lasers, for example. Nevertheless hydrated salts display low intensity and short half live of luminescence. These difficulties can be overcome by coordinating lanthanides to chromophores, organic ligands that may transfer energy (EnT) from the excited state to the emissive state of the lanthanide, that is they act as antenna groups [1]. Reactions of EuIII, GdIII, TbIII and DyIII nitrate salts with the ligands 2-(2-pyridyl)benzimidazole (2pb), 2-(4-thiazolyl)benzimidazole (4tb), tris(2-benzimidazolylmethyl)amine (ntb) yielded coordination compounds of the type: [Ln(NO3)3(L)2]⋅S for L = 2pb and 4tb, [Ln(NO3)2(ntb)]NO3⋅S, and S = solvent (acetone, ethanol, acetonitrile). These complexes were characterised by analytical (elemental analyses) and spectroscopic techniques: IR, 1D and 2D 1H and 13C NMR spectroscopy, the meff of the complexes was determined. Luminescent properties of the complexes synthesised and the ligands were studied. Solid state absorption and emission spectra of the complexes were obtained in the UV-vis region. Ligands themselves show luminescence. The values of the lanthanides complexes luminescence half lives (t) were calculated and range from 0.025 to 1.82 ms. Spectra showed that the benzimidazolic ligands are good candidates for energy transfer to the metal centre. Best luminescence properties were shown by the EuIII complexes. The following figure shows the emission spectrum of [Eu(NO3)2(ntb)]NO3×EtOH and the proposed structure for the cation. EPR spectra of the gadolinium coordination compounds were recorded both at room temperature, solid samples, and in glasses, in dimethylsulfoxide at 77 K. Spectra are discussed herein.

[1] G. R. Chopin, D. R. Peterman, Coord. Chem. Rev. 1998, 174, 283-299.

Keywords: luminescence, lanthanides, EPR

MS.C3.P.373 Ruthenium Complexes Containing 2-(2-Nitrosoaryl)pyridine: Structure, Spectroscopic and Theoretical Studies Siu-Chung Chan, Ho-Yuen Cheung, and Chun-Yuen Wong, Department of Biology and Chemistry,City University of Hong Kong (Hong Kong). E-mail: [email protected]. Ruthenium complexes containing 2-(2-nitrosoaryl)pyridine (ON^N) and tetradentate thioether 1,4,8,11-tetrathiacyclotetradecane ([14]aneS4), [Ru(ON^N)([14]aneS4)]2+ (2a–2d; ON^N = 2-(2-nitrosophenyl)pyridine (a), 10-nitroso-benzo[h]quinoline (b),

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MS.C3.P.371

Poster Sessions 2-(2-nitroso-4-methylphenyl)pyridine, (c), 2-(2-nitrosophenyl)5-(trifluoromethyl)pyridine (d)), and analogues with the 1,4,7-trithiacyclononane ([9]aneS3)/tert-butylisocyanide ligand set, [Ru(ON^N)([9]aneS3)(C≡NtBu)]2+ (4a, 4b) have been prepared by insertion of nitrosonium ion (NO+) into the Ru–aryl bond of cyclometallated Ru(II) complexes. The Ru–NNO and N–O distances, together with the nN=O, suggest that the coordinated ON^N ligands in this work are neutral moiety (ArNO)0 rather than monoanionic radical (ArNO)•1– or dianion (ArNO)2– species. The nitrosated complexes 2a– 2d show moderately intense absorption centered at 463–484 nm (εmax = (5–6) × 103 dm3 mol–1 cm–1) and a clearly discriminable absorption shoulder around 620 nm (εmax = 6 × 102 dm3 mol–1 cm–1) which tails up to 800 nm. These visible absorptions are assigned as a mixing of d(Ru) → ON^N metal-to-ligand charge transfer (MLCT) and ON^N intra-ligand (IL) transitions on the basis of time-dependent density functional theory (TD-DFT) calculations. Both electrochemical data and DFT calculations suggest that the lowest-unoccupied molecular orbitals (LUMOs) of the nitrosated complexes are ON^N-centered. Natural population analysis (NPA) shows that the amount of positive charge on the Ru centers and the [Ru([14]aneS4)] moieties in 2a and 2b are larger than that in [Ru(bpy)([14]aneS4)]2+. According to the results of the structural, spectroscopic, electrochemical and theoretical investigations, the ON^N ligands in this work have considerable π-acidic character and behave as better electron acceptors than bpy.

(AMB) afforded only Binuclear complex [{Cp(CO)2Fe}2(µAMB)](BF4)2. The reaction of [Cp*(CO)2Fe(THF)]+ with an equimolar amount of monometallic complex, [Cp(CO)2Fe(ABN)] BF4 yields a mixed ligand complex [Cp(CO)2Fe(ABN) Fe(CO)2Cp*](BF4)2. Compounds reported here in have been fully characterized by 1H NMR, 13C NMR, IR and elemental analysis. The structures for compounds [Cp(CO)2Fe{NH(CH2CH2CH3)2}] BF4, [Cp*(CO)2Fe(NH2(CH2)2CH2OH)]BF4 and [Cp*(CO)2Fe(NH2C6H4OCH3)]BF4 have been authenticated by single crystal X-ray crystallography and will be discussed (see Fig below).

Molecular structure of [Cp*(CO)2Fe{NH2(CH2)2CH2OH}]BF4, showing atomic numbering scheme

[1] S-C. Chan, P-K. Pat, T-C. Lau, C-Y. Wong, Organometallics, 2011, 30, 1311-1314. [2] S-C. Chan, H-Y. Cheung, C-Y. Wong, Inorg. Chem., 2011, 50, 11636-11643.

Keywords: Ruthenium, 2-(2-nitrosoaryl)pyridine, Insertion

MS.C3.P.374 Water-soluble Heterofunctional Amine Complexes of Iron Dicarbonyl Cations, [(η5-C5R5)(CO)2Fe]+ (R = H, CH3) Evans O. Changamua, Cyprian M. M’thiruaineb, Holger B. Friedrichb, Bernard Omondi,b aChemistry Department, Kenyatta University, P.O Box 43844 Nairobi, Kenya. bSchool of Chemistry, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa. E-mail: [email protected] Solubility of transition metal organometallics in water, though desirable in certain of their applications such as in catalysis, has only been observed with selected few ligands[1]. We have investigated the reactions of the substitutionally labile ether complexes [Cp(CO)2Fe(Et2O)]+, (Cp = η5-C5H5) 1, and [Cp*(CO)2Fe(THF)] BF4 (Cp* = η5-C5(CH3)5), 2, with various heterofunctional amine ligands including 1-aminopropanol, 4-methoxybenzylamine, 3-aminopropyltriethoxysilane and dipropylamine. Results show that the ligands coordinate to the metal regioselectively via the amine functionality to give mononuclear water-soluble complexes of the type, [Cp(CO)2Fe(L)]BF4. The reaction of 1 with 4-aminobenzonitrile (ABN) furnished both mononuclear and binuclear complexes, [Cp(CO)2Fe(ABN))]BF4 and [{Cp(CO)2Fe}2(µ-ABN)](BF4)2, respectively, while its reaction with 1,4-phenylenedimethanamine

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[1] Donald J. Darensbourg, Ferenc Joo, Michael Kannisto, Agnes Katho, Joseph H. Reibenspies, Donald J. Daigle, Inorg. Chem., 1994, 33 (2), pp 200–208.

Keywords: Water-soluble, heterofunctional, regioselective

MS.C3.P.375 Osmium Complexes Containing N-Heterocyclic Carbene-based C,N,C-Pincer Ligands and Aromatic Diimines Lai-Hon Chung, Chun-Yuen Wong, Department of Biology and Chemistry,City University of Hong Kong (Hong Kong). E-mail: [email protected] Osmium(II) complexes bearing C,N,C-pincer ligand 2,6-bis(alkylimidazolin-2-ylidene)pyridine (CNC-Me and CNCBu for alkyl = methyl and n-butyl respectively) or 2,6-bis(3butylbenzimidazolin-2-ylidene)pyridine (CNC’-Bu) and aromatic diimine (2,2’-bipyridine (bpy) / 1,10-phenanthroline (phen)) have been prepared. The X-ray crystal structure of [Os(CNC-Me)(bpy)Cl](PF6) shows that the Os–C bonds are essentially single (Os-C distances = 2.042(4) and 2.059(4) Å). Spectroscopic comparisons on [Os(C,N,C) (diimine)Cl]+ and [Os(tpy)(bpy)Cl]+ (tpy = 2,2’;6’,2”-terpyridine) suggest that the lowest-energy absorption bands for [Os(C,N,C) (diimine)Cl]+ originate from a dp(OsII) → p*(diimine) metal-to-ligand charge transfer (MLCT) transitions. Density functional theory (DFT) calculations reveal that the p*(diimine) levels in [Os(C,N,C)(diimine) Cl]+ are lower-lying than the p*(C,N,C). The Os(II/III) oxidation waves for [Os(C,N,C)(diimine)Cl]+ are reversible with E1/2 = -0.03 to 0.16 V vs. Cp2Fe+/0. The absorption spectra for the Os(III) species have been obtained by spectroelectrochemical method.

Poster Sessions

[1] C.-Y. Wong, L.-M. Lai, P.-K. Pat, L.-H. Chung, Organometallics, 2010, 29, 2533-2539.

Keywords: Osmium, N-Heterocyclic Carbene, Pincer Ligands

MS.C3.P.376

Metal complexes of tripodal tetraamine ligands have received recent attention in many applications, including oxidation of alkanes, radical transfer catalysis, water splitting and phosphodiester hydrolysis. While complexes of tripodal tetraamine ligands incorporating aliphatic and pyridyl donors have been extensively studied, those containing pyrazolyl donors are much less common [1], perhaps because these ligands have been found to decompose during coordination to a metal ion [2]. We have synthesized a variety of new tripodal ligands incorporating three pyrazole moieties with arms of varying lengths and have studied their coordination to a number of different transition metal ions. In the presence of water or alcohols, the free ligands react to give the corresponding tridentate ligand through loss of a pyrazolylmethyl arm, via the intermediacy of the hemiaminal or hemiaminal ether (scheme 1). We have studied this reaction by 1H NMR spectroscopy and mass spectrometry. While the free ligands are unstable in the presence of water or alcohols, we were nevertheless able to isolate complexes of the intact tripodal tetradentate ligands in addition to the those of the corresponding tridentate ligands (scheme 1), and we have observed that coordination to zinc stabilizes the tripodal ligands towards loss of a pyrazolylmethyl arm.

Scheme 1: The reactivity of tripodal ligands containing pyrazolylmethyl moieties, and the usual mode of coordination of the reported tripodal ligands. x, y = 1 or 2. [1]A. G. Blackman, Polyhedron, 2005, 24, 1-39. [2] W. L. Driessen, W. G. R. Wiesmeijer, M. Schipper-Zablotskaja, R. A. G. De Graaff, J. Reedijk, Inorg. Chim. Acta., 1989, 162, 233-238.

Keywords: tripodal ligands, pyrazole, ligand decomposition

MS.C3.P.377 Utilization of Radioelement Compound Synthesis and Coordination Chemistry for the Nuclear Fuel Cycle K.R. Czerwinski, W. Kerlin, E. Johnstone, F. Poineau, P. Weck, P. Forster, T. Hartmann, and A. Sattelberger1, Radiochemistry Program, University of Nevada, Las Vegas 1Energy Engineering and Systems Analysis Directorate, Argonne National Laboratory. E-mail: [email protected] In the nuclear fuel cycle technetium and the actinides, elements with only radioactive isotopes, are of central importance. Compared to other elements on the periodic table, the radioelements are less explored, especially in areas of compound synthesis and coordination chemistry. The nuclear fuel cycle offers opportunities to investigate fundamental and applied radioelement chemistry in more detail. Tc chemistry Waste forms Separations Actindes Nuclear fuel An-Ln separation. Keywords: Actinide nitrides, uranium, neptunium

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Reactivity of Tripodal Ligands Incorporating Pyrazolyl Moieties John Cubanski, James D. Crowley, Allan G. Blackman, Department of Chemistry, University of Otago. E-mail: [email protected]. ac.nz

Poster Sessions MS.C3.P.378

MS.C3.P.380

Wheel-shaped Indium Telluride Nanoclusters Co-crystallized with Iron-phenanthroline Complexes Jie Dai, Qin-Yu Zhu, Department of Chemistry, Soochow University, Suzhou 215123, P. R. China. E-mail: [email protected]

Polymeric 2-Phenyl-2-(P-Tolylsulfonylamino)Acetic Acid Tin Compounds Angélica M. Duarte-Hernández,a Ángel Ramos-Organillo,b Rosalinda Contreras,a and Angelina Flores-Parra,a* aChemistry Department, Centro de Investigación y de Estudios Avanzados (México). bFacultad de Ciencias Químicas, Universidad de Colima (México). E-mail: [email protected]

In the past decade, a significant progress has been made in clusters of metal chalcogenides prepared by solvothermal method. Approximately, there are three series of noteworthy nano-clusters of metal chalcogenides classified from the shape of the clusters. The first is the global one, such as MQ(QR) (M = Cu, Ag, Zn, and Cd, Q = S and Se, R = organic group). The second is a series of supertetrahedral clusters MM’Q (M = Ga, In and M’ = transition metals, Q = S and Se). The third kind of chalcogenido metal nanoclusters is the wheel-shaped clusters, in which the metal atoms are covalent bridged by inorganic chalcogen ions. In contrast to the former two type clusters, the large inorganic nano ring compounds are limited. The known such clusters are of the giant FeS wheels [1]. On the other hand, some efforts have focused on the design and synthesis of the novel chalcogenides or chalcogenidometalates, in which M-phen/bpy complexes are embedded. The M-phen/bpy complexes have an intense metal-to-ligand charge-transfer (MLCT) transition in the visible region, suitable ground- and excited-states, and good stability in the oxidized and reduced forms. Therefore, the fundamental study devoted to the semiconducting clusters co-crystallized with M-phen/ bpy complexes is a particularly challenging. We have demonstrated the use of M-phen/bpy complexes as counterions in preparing compounds with InS Tn clusters [2,3], which opens a new branch of the basic study of organic-inorganic chalcogenido clusters. However, until now, nano scale rings or wheel-shaped clusters with M-phen/bpy complex cations have not been found yet. Herein, we report two wheel-shaped In18Te30 clusters with M-phen complex cations, M = Fe2+ and Ni2+. Structural and optical characters of these compounds are discussed.

The reaction products of the enantiomerically pure 2-phenyl-2(p-tolylsulfonylamino)acetic acid (1) and Me3SnCl and nBu2SnCl2 are reported. The aim is to combine the tin structural versatility [1] with a polyfunctional ligand having a sulfonamide and carboxylic acid as coordinating groups and a rigid conformation [2] in order to explore divers coordination modes and molecular arrangements. The reaction of 1 with NaH in toluene, followed by Me3SnCl gave [2] 143–5 °C; NMR δ119 Sn: + 8.4 ppm. The solid state structure of the trimethyltincarboxylate 2 forms an infinite chain. Each oxygen atom of the carboxylate is bound to a tin atom, and each tin is coordinated by two oxygen from two different molecules. The tin atom is pentacoordinated, (slightly distorted tbp). The oxygen atoms are axial (O-Sn-O 170.9o). The Sn-O bond lengths indicate that one bond is coordinated (2.18 and 2.49 Å). The tin chain forms a ribbon Fig. 1. The two aromatic rings of the ligand are stacked and alternately oriented up and down of the ribbon. Reaction of 1 with nBu2SnO gave a dimeric distannoxane 3. Mp 131-3o; NMR δ119Sn -200.1 ppm. The basic structure of 3 is a planar arrangement of five fused rings Fig. 2a. The central one has two oxygen and two tin atoms, with two five and two six membered rings fused to it. [3] Each dimer is linked to another by four N-H⋅⋅⋅O=C (2.16 and 2.21 Å) and two S=O→Sn bonds (3.36 and 3.29 Å). The dimer association produces a ribbon. The two faces of the ribbon are hydrophobic whereas heteroatoms at the middle of the plane allow the polymer formation through their lone electron pairs coordination bonds, Fig. 2b. All the tin atoms are hexacoordinated by C=O or S=O oxygen coordination.

Fig. 1. Linear polymer of compound 2

Figure 1. Interactions between the wheel-shaped In18Te30N6 anions and Fe-bpy canions.

We are grateful to the National Natural Science Foundation of China (Grants 20971092) and the Education Committee of Jiangsu Province (11KJA150001) for financial support. [1] P. J. Pauzauskie, D. J. Sirbuly, P. Yang, Phys. Rev. Lett. 2006, 96, 143903. [2] Z.-X. Lei, Q.-Y. Zhu, X. Zhang, W. Luo, W.-Q. Mu, J. Dai, Inorg. Chem. 2010, 49, 4385. [3] X. Zhang, W. Luo, Y.–P. Znang, J.-B. Jiang, Q.-Y. Zhu, J. Dai, Inorg. Chem. 2011, 50. 6972.

Keywords: nano cluster, indium telluride, phenanthroline complex

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Fig 2. a) Basic structure of 3. b) polymeric arrangement of 3 [1] A.G. Davis, Organotin Chemistry, 2d. Edition Wiley 2004. [2] R. SalasCoronado, A, Vásquez-Badillo, M. Medina-García, J.G. García-Colón, H. Nöth, R. Contreras, A. Flores-Parra, J. Mol. Structure (Theochem) 2001, 543, 259-275. [3] N. W. Alcock, S. M. Roe. J. Chem. Soc. Dalton Trans, 1989, 15891598.

Keywords: 2-phenyl-2-(p-tolylsulfonylamino)acetic distannoxanes, tin polymers

acid,

Poster Sessions MS.C3.P.381 New Versatile Approach to the Annelated Porphyrin and Dipyrrin Ligands A.V. Dubrovskiy, D.S. Andrianov, A.N. Skabeev, A.V. Cheprakov. Chemistry Department, Moscow State University, Moscow (Russia). E-mail: [email protected] The application of tetrahydroisoindole and dihydroisoindole synthons introduced by us earlier [1, 2] gives an effective synthetic approach to a broad range of multifunctionalized porphyrin and dipyrromethene ligands bearing annelated, partially saturated or aromatic rings. The synthesis of porphyrins can be conveniently realized in aqueous solubilizing systems of high capacity (the Winsor systems). The developed protocol enables high yield direct synthesis of meso-tetraaryl and 5,15-diarylporphyrins involving reactive functionality, such as hydroxyl, amino, boronato, carboxy, etc. groups without the need of protection/deprotection, which is not possible in the conventional methods of porphyrin synthesis. The yields of functionalized porphyrins depend on the nature of solubilizing system used which allows for fine-tuning of a given system to achieve the best yields and system efficiency. The porphyrin ligands of such type are regarded as potential polytopic ligands for new metal-organic frameworks and other applications. Tetrahydroisoindole and dihydroisiondole synthons are also applied for the synthesis of new annelated dipyrromethene ligands. The annelated rings of new porphyrin and dipyrrin ligands can be easily aromatized to afford new pi-extended oligopyrrolic ligands. The thus obtained dipyrromethene ligands possess unique ability to chelate metal (Zn, Cd, Hg, Ca, Pb, rare earths, etc.) ions from solutions giving highly fluorescent complexes (metalloDIPYs) with emission bands tunable in a broad range of 550-900 nm. Further tuning of the annelated dipyrrinic ligands is achieved by chemical modification of α-substituents in pyrrolic rings in order to control the formation of homo- or heteroleptic complexes having dramatically different emissive properties.

Supramolecular coordination networks composed of self assembled metal ions and multidentate organic ligands are of great interest not only because of their fascinating structures but also for their multiple applications like gas storage, catalysis or ion exchanged [1]. We have synthesized two new ditopic ligands: bis(pyrazol-1-yl) (pyridine-4-yl)methane and bis(3,5-dimethylpyrazol-1-yl)(pyridine4-yl)methane (bpzm4py and bpz*m4py) [2]. These ligands react with silver salts, giving rise to complexes with different structures. Because silver does not have a clear preference for any stereochemical environment, weak interactions could play an important role in the final supramolecular structure. When the bpzm4py ligand reacts with Ag(I), box-like cyclic dimmers are obtained (Figure 1). These dimmers are linked either by weak interactions or by covalent bonds involving the anion, giving rise to chains (Figure 2).



Figure 1

Figure 2

In some cases, when bpz*m4py reacts with silver salts, coordination polymers with helix shape are obtained (Figure 3). These complexes contain two alternating different types of silver ions, with tetrahedral and linear coordination. By the appropriate choice of the crystallization conditions, it is possible to direct the reaction towards the formation of box-like cyclic dimmers.

Figure 3.

Some of these complexes could be used as metalloligands, and after the reaction with different linkers coordination polymers of higher dimensionality could be obtained. [1] R. J. Dupler, D. J. Timmons, Q.-R. Fang, Coord. Chem. Rev. 2009, 253, 3042-3066. [2] M.C. Carrión, G. Durá, F. Jalón, B. Manzano, A.M. Rodríguez, Cryst. Growth Des. 2012, 12, 1952-1969.

Keywords: coordination polymer, silver, N-donor ligand

Keywords: porphyrins, dipyrrin, microemulsion

Acknowledgments: MEC of Spain for FPU (GD) and INCRECYT program (MC) and MINECO-FEDER for the projects CTQ2008-03783/BQU and CTQ2011-24434.

MS.C3.P.382

MS.C3.P.383

Silver Coordination Complexes Containing Ditopic Bispyrazolylmethane Ligans Gema Durá,a M. Carmen Carrión,a,b Felix A. Jalón,a Blanca R. Manzano,a Ana M. Rodríguezc. aDepartamento de Química Inorgánica, Orgánica y Bioquímica, Universidad de Castilla-La Mancha, Facultad de Químicas-IRICA, Ciudad Real, Spain. bFundación PCYTA, Paseo de la Innovación, 1, Spain. cDepartamento de Química Inorgánica, Orgánica y Bioquímica, Universidad de Castilla-La Mancha, Escuela Técnica Superior de Ingenieros Industriales, Ciudad Real, Spain. E-mail: [email protected]

Dianionic Mononuclear Ni(II) and Cu(II) Complexes and their Oxidized Species Meital Eckshtain,a Maylis Orio,b Himanshu Arora,a Ronit Lavi,a Dmitry S. Yufit,c Laurent Benisvy*,a aDepartment of Chemistry, Bar-Ilan University, Ramat Gan 52900, Israel. bLaboratoire de Spectrochimie Infrarouge et Raman, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’Ascq Cedex, France. cDepartment of Chemistry, University of Durham, South Road, Durham DH1 3LE, U.K. E-mail: [email protected]

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[1] M. A. Filatov, A. Y. Lebedev, S. N. Mukhin, S. A. Vinogradov and A. V. Cheprakov J. Am. Chem. Soc., 2010 132 (28): 9552-9554. [2] M. A. Filatov and A. V. Cheprakov. Tetrahedron, 2011, 67 (19): 3559-3566.

Poster Sessions Metalloenzymes often involves the presence of a intermediate with a high oxidation state in their catalytic cycle, such as the putative Cu(III) and Ni(III) ions. However, the isolation and characterization of such species remain a significant challenge. With the aim of making dinuclear complexes that can exist in high oxidation state, we have designed a new di- compartmental bis-(phenol diamide) macrocyclic pro-ligand, LH6, the fully deprotonated form of which should provide a polyanionic (N2O2)4- coordination sphere to each metal ions. The presence of both O-phenolate and N-amidate “hard” donor atoms are believed to stabilize high oxidation state.[1] Herein, the synthesis and characterization of LH6 is presented together with its coordination behavior with Cu(II), and Ni(II) ions. The reaction of LH6 with M(II) acetate in the presence of [NBu4][OH] (in ligand: metal: base ratios of either 1:1:4 or 1:2:6) invariably leads to the formation of the corresponding mononuclear dianionic complexes [MLH2][NBu4]2 (M(II) = Ni (1), Cu (2)). The combination of EPR, X-ray crystallography, NMR and UV/vis studies unambiguously reveals an M(II) ion in a square-planar (N2O2)4- coordination sphere from the ligation of two O-phenolate and two N-amidate donor atoms. Interestingly, the second compartment of the ligand remains protonated with both N-H amide bonds being hydrogen-bonded to the coordinated phenolates. The cyclic voltammogram of 12- and 22- each displays a one-electron oxidation process at a relatively low potential (ca. -0.2 V vs. Fc+/Fc), indicating that a higher oxidation state is accessible. Both 12- and 22- are readily oxidized electrochemically or chemically to form the corresponding oxidized species (1- and 2-) that were sufficiently stable to be characterized by UV/vis/NIR and EPR spectroscopy. The experimental data obtained combined with DFT-calculations will be discussed in order to unravel the electronic structure of the oxidized species formed, i.e. M(III) or M(II)-phenoxyl radical species. [1] Popescu, D.-L., Chanda, A., Stadler, M., Tiago de Oliveira, F., Ryabov, A. D., Münck, E., Bominaar, E. L., Collins, T. J., Coord. Chem. Rev., 2007, 252, 2050.

Keywords: phenoxyl radical, Ni(III), macrocycle

MS.C3.P.384 Metallic Ion Influences in Aza-Additions of 2-(Aminomethyl) benzimidazole Martha Falcón-León,a Rafael Tapia-Benavides,a Hugo Tlahuext,b Carlos Galán-Vidal, a Oscar Suárez,a Margarita Tlahuextl*,a aCentro de Investigaciones Químicas, Universidad Autónoma del Estado de Hidalgo, Hidalgo, (México). bCentro de Investigaciones Químicas, Universidad Autónoma del Estados de Morelos, Morelos (México). E-mail: [email protected] The addition of amines to conjugated alkenes (aza-Michael addition) is an outstanding process in the synthesis of organic compounds [1]. The reaction is efficiently in acid and basic media or by catalyst promotion. However, in presence of two or more reactive centrums, the conjugated alkene activation causes that aza-addition processes take place out of control and yield complex mixtures. 2-(Aminomethyl)benzimidazole 1 is a ligand with three reactive centers (a primary amine and two imidazolic nitrogen atoms) and it is an efficient coordinate agent. Moreover, coordination complexes of 1 are excellent molecular models in the study of biological systems as metalloenzymes [2]. The addition of 1 to acrylonitrile was studied in presence of metallic ions (M = Li+, Na+, K+ and Zn(II)). Reactions were made at different pH values. At acid pH, in presence of alkaline ions, the aza-addition is minor 7%. Whereas the reaction at pH > 6 gives mixture of compounds. In all cases, the mono-addition of amine group is the predominant product. Morever, di-addition products on amine and imidazoline groups are always present. On the other hand,

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the use of Zn(II) complexes from 1 promotes the regioselective monoaddition. Different Zn(II) coordination complexes derivates of 1 showed a varied reactivity. The Zn(II) hexacoordinated complex is the best reactive and produce the best yields.

[1] V. Rajalakshmi, V. R. Vijayaraghavan, B. Varghese, A. Raghavan, Inorg. Chem., 2008, 47, 5821-5830. [2] A. R. Tapia-Benavides, M- Tlahuextl, H. Tlahuext, C. Galán-Vidal. ARKIVOC, 2008, v, 172-186.

Keywords: Aza-addition, benzimidazole, acrylonitrile

MS.C3.P.385 Coordination Behaviour of Instant N-Heterocyclic Carbenes Christian Färber,a Clemens Bruhn,a Michael Leibold,a Ulrich Siemeling,a aInstitute of Chemistry, University of Kassel, Kassel, (Germany). E-mail: [email protected] Since their discovery in 1991 [1], N-heterocyclic carbenes (NHCs) have become powerful workhorses in synthesis and catalysis [2]. The most frequently used procedure for generating NHCs is the deprotonation of azolium salts with a strong base [3]. A renaissance of stable carbene availability has recently been achieved by utilising mesoionic compounds bearing an azolium and an amido or azolate moiety in the same molecule. Such compounds represent a masked form of carbenes, since they exhibit typical carbene reactivity via their carbenic tautomer in solution. The low-cost analytical reagent Nitron 1, which has been commercially available for more than a century, was recently recognised as the first example of such an instant NHC [4]. We will present the concept of instant NHCs, demonstrate their versatile reactivity and describe their electronic properties on the basis of the results of DFT calculations. Pertinent aspects of the coordination behaviour of 1 and 2 will be illustrated, focusing on complexes of RhI, RuII and RuIII. In particular, we will address their binding profile, which can range from simple monodentate to C,N-chelating and bridging coordination, hence giving easy access to unusual carbene-amido complexes and bimetallic species.

[1] A. J. Arduengo, R. L. Harlow, M. Kline, J. Am. Chem. Soc. 1991, 113, 361. [2] See, for example: F. E. Hahn, M. C. Jahnke, Angew. Chem. Int. Ed. 2008, 47, 3122. [3] See, for example: T. Dröge, F. Glorius, Angew. Chem. Int. Ed. 2010, 49, 6940. [4] C. Färber, M. Leibold, C. Bruhn, M. Maurer, U. Siemeling, Chem. Commun. 2012, 48, 227.

Keywords: n-heterocyclic carbenes, amido complexes, ruthenium complexes

Poster Sessions MS.C3.P.386

MS.C3.P.387

Developing Chalcogenoether Macrocyclic Complexes with Group II Metals Paolo Farina, William Levason, Gillian Reid, School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ (UK) E-mail: [email protected]

Different Coordination Environment for Several Metals in Coordination Polymers Eva Fernández-Zapico,a Jose Montejo-Bernardo,a José R. García,a Santiago García-Granda,a aDepartments of Physical and Analytical Chemistry and Organic and Inorganic Chemistry, University of Oviedo - CINN, Spain. E-mail: [email protected]

The chemistry of mixed chalcogenoether macrocycles has been much less well explored than that of their homoleptic analogues. There is substantial coordinative flexibility within this ligand class due to the inclusion of both soft (S, Se, Te) and hard (O) donor types within the same macrocycle. Oxa-thia macrocyclic complexes noticeably dominate the known chemistry[1], with there being only three structurally characterised examples of Se/O and Te/O macrocycle coordination complexes, [PdCl2([18]aneO4Te2)] and [PtCl2([18] aneO4E2)] (E= Se, Te)[2]. The coordination chemistry that is known focusses primarily on the late, low oxidation state transition metal ions. A few notable examples of soft thioether coordination to the harder metal cations of the early d-block (e.g. CrIII,TiIV, ScIII, ZrIV, TaV)[1] have been reported, and suggest that a much wider range of thioether coordination chemistry with very hard Lewis acids may be accessible under the appropriate experimental conditions. Within the s-block, the coordination chemistry of the Group I and II metal ions is dominated by crown ethers, and there are only two examples of Group II metal complexes involving thioether coordination known, [Ca(ClO4)2([18] aneS2O4)][3] and [Ba{Cu(SCN)3 ([18]aneO4S2-κS)}][4]. The work presented discusses our recent work on soft chalcogenoether coordination to hard alkaline earth dications, using a range of mixed Group 16 donor macrocycles with varying ring sizes and E:O ratios (E= S, Se, Te). A discussion of the key factors determining the accessibility of these complexes is included.

Six non-isostructural metal(II) coordination polymers were synthesized (metal = Co, Cu, Zn, Cd) under mild hydrothermal conditions (T = 140°C) by mixture of metal(II) acetate with 2-carboxyethylphosphonic acid and 1,10’-phenanthroline [1]. All products were obtained as single-crystals, and their structures were determined by single-crystal X-ray diffraction. In the same synthetic conditions (reagent’s molar ratio 1:1:1) four different crystal structures have been found, depending on the metal, but all crystallizes as discrete dimetallic units. For Zn, varying the time of reaction or the molar ratio of reagents, two different compounds are synthesized. In both cases, three different Zn atoms are present in the structures, showing different coordination environments. Moreover, these two compounds do not crystallize as discrete molecules; one forms layers in ab plane and the other has a three-dimensional structure (MOF). For these six compounds, structural features, including H-bond networks and π—π stacking interactions were reported and discussed here. Acknowledgments. Financial support from Spanish Ministerio de Economía y Competitividad (MAT2010-15094, MAT2006-01997, Factoría de Cristalización – Consolider Ingenio 2010) and FEDER. E. F.-Z. also thanks to the Programa Severo Ochoa – Ficyt for the predoctoral grant (BP 11-142). [1] E. Fernández-Zapico, J. M. MontejoBernardo, R. D’Vries, J. R. García, S. García-Granda, J. Rodríguez-Fernández, I. de Pedro, J. A. Blanco, J. Solid State Chem., 2011, 184, 3289-3298.

Keywords: coordination polymers, metal environment, crystal structure

MS.C3.P.388

Figure 1: View of the structure of [CaI2([18]aneO2S4)] [1] W. Levason and G. Reid, Hetero-Crown Ethers—Synthesis and MetalBinding Properties of Macrocyclic Ligands Bearing Group 16 (S, Se, Te) Donor Atoms in Supramolecular Chemistry: From Molecules to Nanomaterials, Wiley, 2012. [2] M. J. Hesford, W. Levason, M. L. Matthews and G. Reid, Dalton Trans., 2003, 2852. [3] I.-H. Park, K.-M. Park and S. S. Lee, Dalton Trans., 2010, 39, 9696. [4] T. Röttgers, W. S. Sheldrick, Z. Anorg. allg. Chem., 2001, 627, 1976.

Keywords: Chalcogenoether, Macrocycle, Group II

The development of new synthetic methods and the structural characterization of coordination compounds have experimented an extraordinary increase in the last decades [1]. Self-organization of specific molecules using coordination chemistry has been a very useful tool in the construction of supermolecules [2], where strategies for the formation of large aggregates take advantage of intermolecular forces such as hydrogen bonds and pi-stacking [3]. The formation of supramolecular arrays from small building blocks, in the presence of metals, may confer new properties to them such as Lewis acidity, magnetism, luminescence and redox activity [4]. Here we report the synthesis of two novel Cu(II) complexes with ligands based in 2-substituted pyrroles: 2-benzoyl-3,5-dimethylpyrrole (2-bz-pyrrole, C13H13NO) and 2-isonicotinoyl-3,5-dimethylpyrrole (2-py-pyrrole, C12H12N2O). The ligands were synthesized from 2,4-dimethylpyrrole (4.0 mmol) and the aryl chloride (2.0 mmol), benzoyl and isonicotinoyl chloride, respectively. Syntheses were

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Synthesis of 2-Substituted Pyrroles and Ttheir Cu(II) Complexes André L. B. Formiga,a Stella A. Gonsales,a Pedro P. Corbi,a aInstitute of Chemistry, University of Campinas - UNICAMP, 6154, 13083-970 Campinas, SP, (Brazil). E-mail: [email protected]

Poster Sessions performed in CH2Cl2, under reflux and at N2 atmosphere during 10h and 4h, respectively. After extraction with water and brine, purification was achieved through chromatography column. The ligands were obtained as pure compounds, and characterized by single crystal XRD, 1 H and 13C NMR, MS, FTIR and UV-Vis. The complexes were synthesized by the reaction of the respective ligand and CuCl2, in methanolic solutions under alkaline medium. After 15 min of constant stirring, the green solid obtained in each synthesis was vacuum filtered, washed with methanol and dried. Anal. Calc. for [Cu(C13H12NO)2] (%): C, 67.9; H, 5.26; N, 6.09. Found (%): C, 68.3; H, 5.37; N, 6.03. Anal. Calc. for [Cu(C12H11N2O)2] (%): C, 62.4; H, 4.80; N, 12.1. Found (%): C, 62.1; H, 4.74; N, 11.9. Infrared (IR) and electrospray mass spectrometry (ESI-MS) indicated coordination of 2-bz-pyrrole and 2-py-pyrrole to Cu(II) in a bidentate form through the nitrogen atom of pyrrole and the oxygen atom of the carbonyl group. From 2-py-pyrrole, it would be possible to get a supramolecular structure, by coordination of other metals to the N atom of the pyridyl group. For [Cu(2-bz-pyrrole)2] a single crystal XRD study was performed indicating a slightly distorted square planar geometry for Cu(II). The structure is presented in Figure 1.

groups) with copper(II) and zinc ions and studiy of phosphoester hydrolysis mediated by the synthesized complexes. The combined potentiometric and spectroscopic measurements revealed the high tendency of the ligands toward formation of binuclear and polymeric species. According to the EPR and pH potentiometric data obtained for the Cu(II) - L (1:1) system suggested the formation of the dimeric [Cu2L2] and tetrameric [Cu4L4] complexes, which were in rapid equilibrium with one another. X-ray analysis of the isolated tetranuclear complex had shown that it consists of discrete zwitterionic [Cu4L4] clusters involving four square-pyramidal copper(II) centers bridged alternately by the pyrazolate nitrogen atoms, while terminal amino groups of the ligand remained uncoordinated. As a result of addition of two equivalents of copper(II) salt to the basic solution of [Cu4L4], a decanuclear hydroxo-complex [Cu5L2(OH)5(H2O)2]2 was isolated. It had a sandwich-like structure that was formed by the two pentanuclear subunits binding to one another through the bridged hydroxides (Fig.1). The pentanuclear fragment contains two pyrazolate ligands lying opposite to each other and, five copper ions, which are bridged by the hydroxo- and pyrazolate groups in the same plane. The synthesized binuclear zinc complexes appear to be efficient catalysts of the hydrolysis of two phosphoesters, 2-hydroxypropylp-nitrophenyl phosphate and the pesticide paraoxon-ethyl. Drastic differences in the hydrolytic activities of binuclear zinc complexes with ligands having different substitutents are observed and can be attributed to molecular peculiarities. Pyrazolate-bridged dinuclear zinc(II) complexes seem to provide a sufficient number of coordination sites for both activating the substrate and generating the nucleophile.

Figure 1: Crystal structure of [Cu(2-bz-pyrrole)2]. [1] B. J. Holliday and C. A. Mirkin. Angewandte Chemie-International Edition, 2001, 40, 2022-2043. [2] A. G. Montalban, A. J. Herrera, and J. Johannsen. Tetrahedron Letters, 2010, 51, 2917-2919. [3] X. P. Yang, R. A. Jones, R. J. Lai, A. Waheed, M. M. Oye, and A. L. Holmes. Polyhedron, 2006, 25, 881-887. [4] C. J. Jones. Chemical Society Reviews, 1998, 27, 289-299. Financial support: FAPESP and CNPq (Brazilian Agencies)

Keywords: copper(II), pyrrole, supramolecular chemistry

MS.C3.P.389 Bi- and Polynuclear metal Complexes based on Asymmetric Pyrazole Ligands: Structural and Biomimetic Studies Igor O. Fritsky,a Sergey O. Malinkin,a Larysa Penkova,a Matti Haukka,b Agnieszka Szebesczyk,c Elzbieta Gumienna-Kontecka,c Ebbe Nordlander,d Franc Meyer,e aDepartment of Chemistry, Kiev National Taras Shevchenko University, Kiev (Ukraine). bDepartment of Chemistry, University of Eastern Finland, Joensuu (Finland). c Faculty of Chemistry, University of  Wroclaw, Wroclaw (Poland). d Lund University, Center for Chemistry and Chemical Engineering, Lund (Sweden). eUniversity of Göttingen, Institut für Anorganische Chemie, Göttingen (Germany). E-mail: [email protected] Pyrazole-based ligands are subject of much research interest owing to their rich coordination chemistry and a number of established application areas. These polynucleating ligands have proven very useful for nesting several metal ions and keeping them at a fixed distance. The nature of the substituents plays an important role, since they determine the electronic and structural properties of the metal centres. In the present work, we describe the results of our study on complex formation of novel pyrazolate ligands having different substituents in 3- and 5-positions (carboxylic, oxime and azomethine

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Figure 1. Structures of the ligand L (left) and [Cu5L2(OH)5(H2O)2]2 (right).

Keywords: pyrazole, polynuclear complexes, phosphoesters

MS.C3.P.390 Complexes of Zinc(II) with N-Imidazolyl and N-Pyrazolyl Pyrimidine donor ligands: Synthesis, crystal structures and theoretical study Antonio Frontera, Antonio Bauzá, Pere M. Deyà, Departament de Química, Universitat de les Illes Balears, 07122 Palma de Mallorca. E-mail: [email protected] The marvelous gain in knowledge about the nature and incidence of supramolecular non-covalent interactions is clearly connected with the impressive progress achieved in single-crystal X-ray crystallography during the past two decades. Consequently, the phenomenal growth of crystal engineering is based on the increasing awareness of these intermolecular interactions in solid-state structures [1,2]. The chemistry of pyrazoles, imidazoles, pyrimidines and related N-containing heterocyclic derivatives has been of great interest for many years [3]. Such systems play a significant role in many biological processes, due to their coordinating ability to metal ions [4]. The chemistry of transition metals associated with polydentate ligands with sp2 hybridized nitrogen atoms yields to very interesting inorganic architectures [5].

Poster Sessions

[1] G. R. Desiraju, J. J. Vittal, A. Ramanan in Crystal Engineering A Textbook. World Scientific Publishing, Singapore, 2011. [2] Organic Crystal Engineering: Frontiers in Crystal Engineering, (Eds.: E. R. T. Tiekink, J. Vittal, M. Zaworotko), John Wiley & Sons Ltd., Chichester, UK, 2010. [3] S. W. Lai, T. C. Cheung, M. C. W. Chan, K. K. Cheung, S. M. Peng, C. M. Che, Inorg. Chem. 2000, 39, 255–262. [4] E. I. Solomon, M. J. Baldwin, M. D. Lowery, Chem. Rev. 1992, 92, 521–542. [5] E. Breuning, M. Ruben, J.-M. Lehn, F. Renz, Y. García, V. Ksenofontov, Ph. Gütlich, E. Weglius, K. Rissanen, Angew. Chem., Int. Ed. 2000, 39, 2504–2507.

Keywords: Anion–π and p–π interactions, Zn complexes, ab initio calculations

MS.C3.P.391 X-Ray Photoelectron Spectra of Nickel(II) Complexes Manabu Fujiwara, Tomoya Adachi, Takayuki Matsushita, Faculty of Science and Technology, Ryukoku University, Otsu, (Japan). E-mail: [email protected] X-ray photoelectron spectroscopy (XPS) is a powerful tool to determine the binding energy of electrons. So that the energy change of core electron orbitals can be directly evaluated. On the other hands, the coordination structure is strongly related to the magnetic susceptibility on the nickel(II) complexes. In this study, XPS spectra of nickel(II) complexes and salts with a variety of coordination structures. The relationship between the coordination structures and the electronic states for nickel(II) complexes has be clarified from the data of spectral shapes and peak positions. The nickel(II) complexes with a variety of coordination structures were prepared in a general manner, and identified by elemental analysis, UV-vis and MS spectrometries, and magnetic susceptibility. XPS spectra of the complexes are measured on a ESCA-1600R (ULVAC-PHI) spectrometer. The Mg-Kα X-ray line (1253.6 eV, 400 W) was used as the excitation source. The measurements were made at ambient temperature under a vacuum of < 1×10-6 Pa. XPS (Ni2p) spectra of nickel(II) complexes with tetrahedral, octahedral and square planar coordinations are shown in Fig. 1, (1) tetrahedral: Ni(tert-Bu-sal)2, (2) Octahedral: [Ni(NH3)6]Cl2, (3) square

planar: Ni(Hdmg)2. these peak shapes are largely different from each other. The spectra of (1) and (2) have the satellite peaks with high intensities around 860 and 880 eV, respectively. On the contrary, no obvious satellite peaks were observed for (3). The existence of unpair electrons is mainly responsible for the intensities of satellite peaks, also for the values of magnetic susceptibility. For Ni(Hdmg)2 with square planar coordination, the Ni2p3/2 main peak appears at the lowest energy among them, suggesting that its coordination bonds between central nikel(II) ion and nitrogen donor atoms is the strongest with covalent character.

Fig. 1 XPS (Ni2p) spectra

Key words: X-ray photoelectron spectra, Nickel(II) complexes, Coordination structures

MS.C3.P.392 Tetracoordinated Boron Complexes Derived from Various 1,3-Diketones Petra Galer, Jože Koller, Berta Košmrlj, Maja Vidmar, Boris Šket. University of Ljubljana, Faculty of Chemistry, Ljubljana (Slovenia). E-mail: [email protected] Incorporation of main group elements into the П-conjugated frameworks is a powerful approach to modifying the nature of the parent П-conjugated systems. Boron also has several characteristic features, such as an effective orbital interaction with the П-conjugated frameworks through the vacant p-orbital, high Lewis acidity, and trigonal planar geometry. A number of boryl-substituted П-conjugated systems have been synthesized to date. By connecting the boron with П-conjugated system, pп–П* conjugation effectively takes place, leading to the appearance of unique electrone and photophysical properties. β-Diketonate is well-known as O,O-donor ligands for transitionmetal center and lanthanides. Herein, we report the syntheses, structures and photochromic properties of some β-diketonate ligand as substituted 1,3-diphenylpropane-1,3-dione and methoxy substituted 1,7-bisphenyl1,6-heptadiene-3,5-dione and their boron(III)tetra coordination compounds. Using 1-phenyl-3-(3,5-dimethoxyphenyl)-propane-1,3-dione as starting compound, we were able to prepare a series of halo substituted compounds with halogen bonded at position 2 and 6 in activated

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The synthesis and crystal structure determination of three zinc(II) complexes with 2-(1H-imidazol-1-yl)-pyrimidine (imipyr), 2-(1H-pyrazol-1-yl)-pyrimidine (pyrapyr) ligands are reported here. Complexes [Zn(imipyr)2Cl2] (1) and [Zn(pyrapyr)2Cl2] (2) are mononuclear systems and [Zn2(pyrapyr)2(Cl)4] (3) is a dinuclear complex with two chlorido bridging ligands. In this complex, the coordination index of one Zn is four and the other is six. All complexes have been characterized by X-ray crystallography and spectral analysis. A high level theoretical study has been performed in order to rationalize the interesting noncovalent interactions observed in the solid state. That is, all three structures present a peculiar p-stacking, characterized by the absence of p–p ring plane overlapping. In this slipped stacking mode the rings are antiparallel displaced where alternating C•••N interactions are established. Moreover, complex 3 forms infinite 1D columns by means of double anion–p interactions with pyrapyr. Bader’s theory of “atoms in molecules” (AIM) is used to characterize the anion–π and p–π interactions observed in the solid state. A high-level ab initio study (RI-MP2/def2-TZVP level of theory) has been performed to analyse the anion–π binding affinity of the pyrapyr ligand when it is coordinated to the transition metal. Finally, a search in the CSD demonstrate that the structure of 3 is quite unique since dinuclear Zn complexes where one metal is tetracoordinated and the other hexacoordinated is rare, whilst is common in trinuclear linear complexes. This simultaneous tetra and hexacoordination using a bridging chlorido ligand is unprecedented.

Poster Sessions phenyl ring. The chelative complex formation in borates utilizes the non-bonding electrons on the carbonyl oxygen in coordination with the boron vacant p-orbital, results in a resonance-stabilized ring where the n-electrons are lowered considerably and the highest energy П-orbital becomes the HOMO. Supporting evidence for the chelate formation in BF2 complexes has been discussed on the basis of the X-ray crystallography and NMR spectroscopic data. It has been shown that the parent compounds have the n,П* configuration as the lowest singlet excited state, but the corresponding boron complexes have the П,П* configuration. As the 2,6-dihalo-3,5-dimethoxyphenyl ring is ortogonal to the central 1,3-diketonatoboron ring, the influence on the conformation of these ring due to the nature of halogen bonded is relatively small. The difference in chemical shift for 11B in NMR spectra and also redox potential difference will be presented. To determine how the extended conjugation influence on coordinated boron complexes with 1,3-diketone, several di- and tri-methoxy substituted curcumines were prepared. The results obtained show that the central 1,3-diketonato boron ring is still nearly symmetrical and the number and position of methoxy group has only a slight influence on its geometry. Configuration in solid, solution and theoretical calculation (in gas and solution) will be presented.

Phosphine-stabilized germylenes reacted with dimer complex [Rh2(m-Cl)2(COD)2] to produce the corresponding phosphinegermylene-rhodium complexes 2. It is interesting to note that the stability of the Rh(I)-germylene complexes depends on the substituent of germylene fragment. Indeed, the chloro-germylene complex 2a isomerizes into a metallacycle rhodium complex via germylene insertion into the Rh-Cl bond, while the phenyl-substituted one was isolated as the first stable Rh-germylene complex with a Rh-Cl bond.

[1] M. F. Lappert, R. S. Rowe, Coord. Chem. Rev., 1990, 100, 267. [2] (a) S. K. Mandal, H. W. Roesky, Acc. Chem. Res., 2012, 45, 298; (b) W-P Leung, K-W. Kan, K-H. Chong, Coord. Chem. Rev., 2007, 251, 2253. [3] N. Bruncks, W. W. du Mont, J. Pickardt, G. Rudolph, Chem. Ber., 1981, 114, 357. [4] A. F. Richards, A. D. Phillips, M. M. Olmstead, P. P. Power, J. Am. Chem. Soc. 2003, 125, 3204. [5] N. D. Raddy, A. Jana, H. W. Roesky, P. P. Samuel, C. Schulzke, Dalton Trans., 2010, 39, 234. [6] J. Berthe, J. M. García, E. Ocando, T. Kato, N. Saffon-Merceron, A. De Cózar, F. P. Cossío, A. Baceiredo. J. Am. Chem. Soc., 2011, 133, 15930.

Keywords: 1,3-diketones, tetracoordinate boron

Keywords: phosphine-stabilized germylene, germylene-rhodium complex, metallacycle rhodium complex

MS.C3.P.394

MS.C3.P.395

New Rhodium Complexes with phosphine-stabilized germylenes as ligands Juan Manuel García,a,b Edgar Ocando-Mavárez,b Tsuyoshi Kato,a David Santiago Coll,b Alexander Briceño,b Nathalie Saffon-Merceron,a Antoine Baceiredo,a aLaboratoire Hétérochimie Fondamentale et Appliquée, Université Paul Sabatier (UPS), Toulouse (France). b Laboratorio de Fisicoquímica Orgánica, Centro de Química, Instituto Venezolano de Investigaciones Científicas (IVIC), Caracas (Venezuela). E-mail: [email protected]

Aqueous Solution Behaviour of Mo3S4 Clusters with Hydroxypropyl Diphosphine Ligands Manuel G. Basallote, a M. Jesús Fernández-Trujillo,a Jose A. PinoChamorro, a Tomás F. Beltrán,b Carolina Corao,b Rosa Llusar,*, b Maxim Sokolovb ,d and Cristian Vicent.c aDepartment of Inorganic Chemistry, Faculty of Science, University of Cadiz, Cadiz (Spain). bDepartament de Química Física i Analítica, Universitat Jaume I, Campus de Riu Sec, Castelló, Spain. c Serveis Central d’Instrumentació Científica, Universitat Jaume I, Campus de Riu Sec, Castelló, Spain. d Nikolaev Institute of Inorg. Chem. SB RAS, Prospekt Lavrentyeva 3, Novosibirsk, Russia. E-mail: [email protected]

Germylene compounds have attracted growing interest for their potential use as ligands for transition metals [1]. These compounds are highly reactive and tend to oligomerise or polymerize, however, they can be stabilized kinetically by sterically demanding substituents and/or thermodynamically by inter- or intramolecular coordination of Lewis base ligands [2]. The stabilization strategy using neutral donor ligands have led to the formation of three-coordinate Ge(II) species which remain capable of binding to transition metals [2]. Despite phosphines are considered excellent ligands in organometallic chemistry, few phosphine-stabilized germylenes have been isolated to date and ligand properties of these stabilized germylenes were not studied [3-5]. Recently we have prepared several phosphine-stabilized germylenes 1 [6], and in this work, we will present their potential as novel ligand to prepare new rhodium complexes.

C322

The [Mo3S4Cl3(dhprpe)3]+ (1+) cluster cation containing the water soluble 1,2-bis(bis(hydroxypropyl)-phosphino)ethane (dhprpe, L) ligand has been prepared and its crystal structure has been determined by X-ray diffraction. The structure is incomplete cuboidal with a capping and three bridging sulfides, the octahedral coordination around each metal center being completed with a chlorine and two phosphorus atoms of the diphosphine ligand. At high pH, the hydroxo groups of the functionalized diphosphine substitute the chloride ligands and coordinate to the cluster core, giving the new [Mo3S4(dhprpH)3]+ (2+) cluster containing tridentate deprotonated dhprpe ligands.

Poster Sessions

[1] A. G. Algarra, M. G. Basallote, M. J. Fernandez-Trujillo, E. Guillamon, R. Llusar, M. D. Segarra, C. Vicent, Inorg. Chem., 2007, 46, 7668.

Keywords: kinetics, cluster, solution behaviour

MS.C3.P.396 Steric Effects of Macrocyclic Ligands Driving Unusual Sm(II/III) Reductions Michael G. Gardiner,a aSchool of Chemistry, Private Bag 75, University of Tasmania, Hobart TAS 7001 (Australia). E-mail: Michael. [email protected] We have been studying lanthanide complexes derived from various modified calix[4]pyrroles in a range of processes. Initial studies on the trans-N,N’-dimethyl substituted system, 1, indicated that the macrocycle greatly hinders two-coordination site chemistry of ancillary ligands for smaller lanthanide ions. The solvent free, monomeric structure of the methyl complex and its low reactivity is a good example of this. We have continued to exploit this outcome, studying species with bulky ancillary ligands, such as (traditionally) chelating diazabutadienes, and p-bound ligands, such as cyclopentadienyls and COT.

Many outcomes since these initial published examples do not mirror the structures and/or reactivities of [(C5Me5)2SmR] analogues. As a taster, we have observed the first end-on bound N2 complex and shown the ability to vary heterocycle reduction outcomes from reductive coupling, through single electron reduction to neutral adduct formation. In contrast to these sterically driven outcomes, the m-phenylenebased macrocycle 3 acts as a “jack-in-the-box” ligand. It has the ability to offer a high coordination number in stabilising Ln(II) centres and adapt its binding mode in response to ancillary ligand binding, whereby the coordination number can vary in extreme between h1:h6:h1:h6- to h1:h1:h1:h1-. Our initial findings on exploiting this flexibility will be reported.

Keywords: organometallic, lanthanide, reductant

MS.C3.P.397 First Bis-Cyanoximes: New Versatile Multidentate Building Blocks for MOFs Scott Curtis, Carl Cheadle, Olesya Ilcun, Nikolay Gerasimchuk. Department of Chemistry, Missouri State University, Springfield (USA). E-mail: [email protected] First bis-cyanoximes I-III were synthesized and characterized using IR-, UV-visible, 1H,13C NMR spectroscopy and X-ray analysis. Compounds are weak acids (pKa1~5), deprotonation of which leads to yellow solvatochromic dianions. Bis-cyanoximes represent multidendate ionazible ligands capable of formation of extended MOFs that do not require presence of external anions in the crystal lattice. Ligands I and II are rigid conjugated spacers, while bis-cyanoxime III is significantly more flexible which is evident from its rich variable temperature NMR spectra. Reactions of solid HL with hot aqueous solutions of Tl2CO3 lead to Tl2L (L=I-III) in high yields. Crystal structures of all three Tl2L were determined and revealed formation of elegant 3D-coordination polymers in which bis-cyanoximes act as bridging ligands. These centrosymmetric complexes contain planar Tl2O2 rhombs connected into the double-stranded, “ladder-type” structural motif. There are short Tl---Tl thallophillic interactions in Tl2(I) and Tl2(II) at ~3.76 Å which are very close to 3.41 Å intermetallic distance in Tl. Reaction of Na2L with AgNO3 in aqueous solutions at room temperature quantitatively affords insoluble and light insensitive yellow-orange coordination polymeric Ag2L (L=I-III). Chemical and physical properties of all synthesized complexes are discussed.

P.MS.C3

A detailed study based on stopped-flow, 31P{1H} NMR, and electrospray ionization mass spectrometry techniques has been carried out to understand the acid-base behaviour and the kinetics of interconversion between the 1+ and 2+ forms. Both the conversion of 1+ to 2+ and its reverse process occur in a single kinetic step, so that reactions proceed at the three metal centres with statistically controlled kinetics. The values of the rate constants under different conditions are used to discuss on the mechanisms of opening and closure of the chelate rings. Financial support by the Spanish MICINN (Proyecto CTQ200914443-C02-01) is gratefully acknowledged.

Keywords: bis-cyanoximes, Tl(I) coordination polymers

C323

Poster Sessions MS.C3.P.398

MS.C3.P.399

Supramolecular Study of Pt(II) Complexes Containing the Bidentated Ligand [C6H4(PPh2)-2-(CH2NMe2)] Juan Manuel Germán Acacioa, Marco Antonio Villafán-Enriquezb, Jaime Gerardo Fierro-Ariasb, Carmela Crisóstomo-Lucasb and David Morales-Moralesb. aCiencias Básicas e Ingeniería, Recursos de la Tierra, Universidad Autónoma Metropolitana, Av. Hidalgo Poniente, La Estación Lerma, Lerma de Villada, Estado de México, CP 52006, México. b Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, DF. C.P. 04510, México. E-mail: [email protected], [email protected]

Chiral Carborane Based N,O-Ligands: First Co and Fe Complexes and their Properties José Giner Planas,a Florencia Di Salvo,a Min Ying Tsang,a Francesc Teixidor,a Clara Viñas,a Mark E. Light,b Michael B. Hursthouse,b Núria Aliaga-Alcalde,c Duane Choquesillo-Lazarte,d aInstitut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, Bellaterra, (Spain). bSchool of Chemistry, University of Southampton, Highfield, Southampton, (UK). cICREA Junior Researcher and Departament de Química Inorgànica, Universitat de Barcelona (UB), Barcelona, (Spain). dLaboratorio de Estudios Cristalográficos, IACT-CSIC, Armilla, Granada, (Spain). E-mail: [email protected]

This work presents the results of the studies from the crystal engineering point of view of eight crystal structures of Pt(II) complexes including the P-N chelating bidentated ligand [C6H4(PPh2)2-(CH2NMe2)], scheme 1. Complex [Pt(Cl)2{(C6H4(PPh2)-2(CH2NMe2)}] (1) was reacted with different thiolate lead salts [Pb(SR)2] via metathesis reactions to produce the corresponding complexes 2 trough 8, where the nature and thus the donor properties of the benzenethiolates is varied, modifying the content and position of fluorine atoms within aromatic ring, and in the case of complex (8) a carboxylic acid group is included. The study was carried out to rationalize the vast quantity of interactions involved in the crystalline stabilization and supramolecular arrangements found in these platinum complexes. Many interesting interactions have been identified, including: C-H···F-C, C-F···F-C, C-H···Cl-Pt, and the homomeric hydrogen bonding COOH···COOH.

[1] J. G. Fierro-Arias, R. Redon, J. J. Garcia, S. Hernandez-Ortega, R. A. Toscano, D. Morales-Morales, J. Mol. Cat. A. Chem. , 2005, 233, 17-27. [2] O. Baldovino-Pantaleon, J. Barroso-Flores, J. A. Cogordan, S. Hernandez-Ortega, R. A. Toscano, D. Morales-Morales, J. Mol. Cat. A. Chem. , 2006, 247, 6572. [3] O. Baldovino-Pantaleon, D. Morales-Morales, S. Hernandez-Ortega, R. A. Toscano, J. Valdes-Martinez, Cryst. Growth Des., 2007, 7, 117-123. [4] M. Corona-Rodriguez, S. Hernandez-Ortega, J. Valdes-Martinez, D. MoralesMorales, Supramolecular Chem., 2007, 19, 579-585.

Keywords: structures

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Platinum

Complexes,

benzenethiolates,

crystal

The coordination chemistry of the simple ligand 2-hydroxymethyl pyridine (hmpH) (Fig.) towards a wide range of transition metal ions has afforded a large family of structures with various interesting architectures and properties [1]. We have recently described the synthesis, molecular and supramolecular characterization of a series of new nitrogenated aromatic carboranyl alcohols (1 and 2a-c in Fig.) [2]. These compounds, that are prepared in very good yields from one pot reactions, can be regarded as hmpH ligands where one of the H atoms at the CH2 position of the alcohol arm has been replaced by a carboranyl fragment. The success of this procedure has opened a new door toward the synthesis of very attractive, yet unexplored, carborane based transition metal complexes. The high thermal and chemical stability, hydrophobicity, acceptor character, ease of functionalization and three-dimensional nature of the icosahedral carborane clusters make these new molecules valuable ligands in coordination chemistry. In addition, the asymmetry and chiral nature of these ligands, together with their ability for establishing H-bonds, will provide intrinsic features to the final metal complexes allowing unique fingerprints. Herein, we report our initial studies on the metallosupramolecular chemistry of these yet unexplored class of carborane-based chiral N,O ligands, which includes the synthetic procedure, structures, chlathrating and magnetic properties of new cobalt and iron complexes.

[1] T. Taguchi, W. Wernsdorfer, K. A. Abboud, G. Christou, Inorg. Chem. 2010, 49, 10579 and references there in. [2] F. Di Salvo, J.G. Planas, B. Camargo, Y. Garcia, F. Teixidor, C. Viñas, M.E. Light, M. B. Hursthouse, CrystEngComm, 2011, 13, 5788.

Keywords: Boron Engineering

clusters,

Molecular

materials,

Crystal

Poster Sessions MS.C3.P.400 Kinetic and Mechanistic Study of Monodentate Dppm Substitution Involving Organoplatinum (II) Complexes Mohsen Golbon Haghighi, S. Masoud Nabavizadeh, Mehdi Rashidi,* Chemistry Department, College of Sciences, Shiraz University, Shiraz, (Iran). Email: [email protected] The study of the cyclometalation reactions is of considerable interest from their role in many applications, such as the fuctionalization of C-H bonds, anti-cancer drug, luminescence, etc. [1]. Ligand substitution reaction involving transition metal complexes is usually considered as a key step in many catalytic reactions [2]. However, such reactions have rarely been considered on cycloplatinted complexes [3]. In this study, a cyclometalated organoplatinum complex containing monodentate dppm ligand, [Pt(C^N)(R1)(κ1-dppm)], 1, in which dppm = bis(diphenylphosphino)methane, C^N = deprotonated 2-phenylpyridine or benzo[h]quinolone, and R1 = methyl or para-tolyl, is reacted with [Pt(R2)2(L)2], 2, in which R2 = para-anisol, para-tolyl, para-flourophenyl, para-t-butylphenyl, phenyl or methyl and L = SMe2 or DMSO, to produce compounds 3 and 4. The kinetic of reaction of compound 1 with 2 was investigated by using room temperature 1 H NMR spectroscopy. Also reaction of 1 with [Pt(R3)2(COD)], 3, in which R3 = methyl or para-anisol, COD = 1,5-cyclooctadiene, gave different products 4 and 5 through different intermediates. Low temperature 1H NMR and 31P NMR spectroscopies were used to pin down these intermediates. On the basis of these results a mechanism has been suggested for the reaction. The intermediates were fully characterized by using multinuclear NMR studies.

Crystal structures of [Ln(Ur)4(H2O)4]I3 (Ur = urea;Ln = Y, La– Nd, Sm–Lu) and [Ln(Ur)8][I5][I3]2[I2] (Ln = La,Dy) are discussed. The coordination polyhedron of eight oxygen atoms is a distorted square antiprism. No tetrad effect was found for Ln–O bond lengths in [Ln(Ur)4(H2O)4]I3. The most striking feature of the [Ln(Ur)4(H2O)4]I3 structures is the presence of two types of coordinated urea molecules. In the complexes, there are two planar symmetric and two nonplanar asymmetric urea molecules. The Ln–O–C bond angles vary in the 163.06–165.71º and 148.42–152.42º ranges for symmetric and asymmetric urea ligands, respectively, correlating with the ionic mode of urea coordination.In [Dy(Ur)8][I5][I3]2[I2], all urea molecules are planar symmetric.The Dy–O–C angles (127.81–144.31°)indicate covalent mode of urea coordination supporting increase of metal–urea covalence with increase of the number of urea molecules in the inner spheres of rare-earth complexes. In [Ln(Ur)4(H2O)4]I3, the iodide ions form triple columns arranged between the double layersof complex cations.The crystal structure is stabilized by the system of intermolecular hydrogen bonds involving outer-sphere iodide ions and hydrogen atoms of urea and water ligands. In [Ln(Ur)8][I5][I3]2[I2], the V-shaped I5– ions are united in infinite panar twisting chains. The chains are connected by short contacts through bridging V-shaped I5– ions (combined of I­2 molecule and I3– ion) and symmetric I3– ions. Another I3– ion is isolated. The bonded iodine atoms form hexahedral channels, and the columns of the complex cations are localized in these channels and stabilized by hydrogen bonding of the N–H...I type. Keywords: Rare-earths, urea, polyiodides

MS.C3.P.402

[1] J. Dupont, C. S. Consorti, J. Spencer, Chem. Rev., 2005, 105, 2527. [2] M. L. Tobe, J. Burgess; Inorganic Reaction Mechanism, Logman, Essex, UK, 1999. [3] S. Masoud Nabavizadeh, Mohsen Golbon Haghighi, Ahmad R. Esmaeilbeig, Fatemeh Raoof, Zeinab Mandegani, Sirous Jamali, Mehdi Rashidi, Richard J. Puddephatt; Organometallics, 2010, 29, 4893.

Keywords: Organoplatinum, Substitution bis(diphenylphosphino)methane (dppm)

Reaction,

Copper(II), together with other metal ions such as chromium(II) and rhodium(II), is known to form readily dinuclear complexes of the paddle wheel type with the general formula M2(X2CR)4 (X = O, N) with bridging ligands acetate or carboxymidate [1]. We report on the synthesis of new polycarboxylate ligands designed to chelate two or more carboxylates bridging the same metal pair [2]. We have studied the behavior of these ligands with copper(II) and obtained a number of new multinuclear complexes. For example, the ligand N,N,N’,N’-tetrakis(2-methylbenzoic acid)-1,4-diaminomethylbenzene has four carboxylate groups available for bonding. The product obtained with copper(II) depends on the degree of deprotonation of the ligand. If all carboxylates are deprotonated, but the amine functions of the ligand are protonated, we obtain a tetranuclear species, with a central chloride ion. If the ligand is fully deprotonated, an octanuclear species with a box-like structure is obtained. Both have been characterized by X-ray crystallography.

MS.C3.P.401 Various Types of Urea Coordination in Rare-Earth Complex Iodides and Polyiodides DenisGolubev,a Elena Savinkina,a Mikhail Grigoriev,b Dmitry Albov,c a Department of Inorganic Chemistry, Lomonosov University of Fine Chemical Technology, Moscow (Russia). bFrumkin Institute of Physical Chemistry and Electrochemistry, Moscow (Russia). cFaculty of Chemistry, Moscow State University, Moscow (Russia). E-mail: [email protected]

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P.MS.C3

Tetracarboxylate Ligands as Supports for New Copper(II) Paddlewheel Complexes Antoine Gomilaa, Sylvain Duvala, Céline Besnardb et Alan F. Williamsa, a Département de chimie minérale et analytique, Université de Genève, Genève (Suisse) b X-ray crystallography Laboratory, Université de Genève, Genève (Suisse)

Poster Sessions Keywords: fluorescent sensors, amplified signaling, metal coordination

MS.C3.P.404 Functional Vic-Dioxime Ligands and Their Complexes; Synthesis, Electrochemistry and Electrical Properties Armağan Günsel, Mutlu Ünügür, M. Nilüfer Yarasir, Mehmet. Kandaz, Sakarya University, Department of Chemistry, 54140 Esentepe, Sakarya, Turkey. E-mail:[email protected]

[1] M. Eddaoudi, D. B. Moler, H. L. Li, B. Chen, T. M. Reineke, M. O’Keeffe, O. M. Yaghi, Acc. Chem. Res., 2001, 34, 319. [2] F. Dai, H. He, D. Gao, F. Ye, X. Qiu, D. Sun, CrystEngComm, 2009, 11, 2516.

Keywords: copper, polynuclear complexes, self-assembly

MS.C3.P.403 Fluorescent Sensors Based on Amplified Signaling Responses upon Coordination with Metal ions Orhan Güney,a Fehmi Karagöz,a Mehmet Kandaz,b aDepartment of Chemistry, Faculty of Science and Letters, Istanbul Technical University, Istanbul (Turkey). bDepartment of Chemistry, Sakarya University, Sakarya (Turkey). E-mail: [email protected] Selective and sensitive detection of metal ions with fluorescent sensors have been essential tools not only in the field of biology but also in clinical and environmental studies. These fluorescent sensors have been used in bioinorganic chemistry to understand the effects of metal ions producing toxic effects in cells, on the human body. The design of original sensor required that the fluorescent response should be incorporated into the recognition elements. Therefore, to create a sensor for a particular analyte, both the recognition and the fluorescent signal need to be optimized. Hence, we prepared optochemical sensors based on fluorescence quenching depends on metal ions concentration by immobilizing a fluorophore on a solid substrate and monitoring the change in optical properties of the sensing layer upon interaction with the analyte [1,2]. When the changes of fluorescence caused by chelation of metal ions are significant and detectable, the chromophore could be used as a fluorescent chemosensor [3]. In order to extend the scope of the metal ion sensing to other sensory units, we designed new phthalocyanine(Pc) which bears peripheral derivative of benzofuran substituent to be used as a fluorescent chemosensor for the purpose of quantitative detecting of Ag(I) ion based on amplified fluorescence quenching [4]. A comparative study on silver ion recognition property of Pc was carried out to elucidate the substitution effect on sensing ability of fluoroprobe. We recently described the synthesis and photophysical evaluation of an acridine-derivated receptor for selective mercury binding based on chelation-enhanced fluorescence effect. The chemosensor for recognition of mercury metal ion displayed high selectivity upon formation of a coordination complex [5]. [1] O. Güney, Y. Yılmaz and Ö. Pekcan, Sens. Actuators B, 2002, 85, 86-89. [2] O. Güney, F.Ç. Cebeci, J. Applied Polym. Sci.,2010, 117: 2373–2379. [3] A.A. Esenpınar, M. Kandaz , A.R. Ozkaya, M. Bulut, O.Güney, J. Coord. Chem , 2008, 61, 1172–1183. [4] M. Kandaz, O. Güney, F.B. Senkal, Polyhedron, 2009, 28 3110–3114. [5] F. Karagöz, O. Güney, M. Kandaz, A. T. Bilgiçli, J. Lumin, 2012, (in press).

C326

There has been keen current interest to the oximes ligands which bear specially-designed “active” functionalities on them for coordinating different transition metals. The ligands forming multinuclear complexes are of great interest for obtaining special magnetic, optical and electrical properties[1-4]. In the present study, we present the improved efficient synthesis for preperation of mono-, di- and trinuclear vic-dioxime complexes by attaching spectroscopic-active amide functionality to outer site of vic-dioxime core. Therefore, thiophen-2-ylmethan- amine, dioctyl amine, dodecyl amine and 2-(2-aminoethoxy) ethanol double functional reagents were introduced as condensa- tion starting compounds to the dimethyl 2,2’-(1,2-bis (hydroxy imino)ethane1,2-diyl)-bis(sulfanediyl)diacetate. We have therefo- re, prefered and obtained dimethyl-2,2’-1,2-bis(hydroxyimino) ethane-1,2-diyl)bis(sulfanedily)diacetate. oxime ligand by the rection between (E,E)dicholoro glyoxime and methyl-2-mercapto acetate in n-EtOH for further multi functional ligands bearing different donors. Homo or heterotritrinuclear complexes were carried out simul taneously or one after another in the presence of basic condition either THF and DMF solvent at 40 °C via deprotonation of -N-OH and – CONH moieties. The structure of the dioxime and its complexes are proposed in accordance with the elemental analysis, 1H-NMR, UVVis, FT-IR and MS-FAB spectral data.

[1] M.U. Anwar, L.N. Dawe, L.K. Thompson. J. Chem. Soc., Dalton Trans. 2011, 40 (32) 8079. [2] S.K. Samanta, A. Pal, S. Bhattacharya. Langmuir. 2009, 25, 8567. [3] M. Kandaz,.; I. Yılmaz; S. Keskin; A. Koca, Polyhedron, 2002, 21, 825. [4] U. Griesbach, D. Zollinger, H. Putter, C. Comninellis, J. Appl. Electrochem. 2005, 35, 1265.

Keyword: Vic-dioximes voltammetry

Complexes,

Condensation,

Cyclic

Poster Sessions MS.C3.P.405 Functionalized Ag(I)- and Hg(II)-N-heterocyclic carbene complexes of CCC, CNC and NCN pincer-type ligands: structural diversity Rosenani A Haque,a Muhammad Adnan Iqbal,a aSchool of Chemical Sciences, Universiti Sains Malaysia, 11800-USM, Penang, (Malaysia) E-mail: [email protected]

[1] RA. Haque, AW. Salman, SG. Teoh, HH. Abdallah, J. Organomet. Chem, 2011, 696, 3507-3512.

Keywords: N-Heterocyclic carbenes, Ag(I)- and Hg(II)-complexes, FT-IR

MS.C3.P.406 Crystallographic Study of Different O,O’-Bidentate Complexes of Niobium(V) L. Herbsta, H.G. Vissera, A. Roodt,a aDepartment of Chemistry, University of the Free State, Nelson Mandela Avenue, Bloemfontein 9300, South Africa. E-mail: [email protected] Niobium and tantalum were discovered early in the nineteenth century and since then great difficulty has been experienced in separating them, due to their similarity in chemical properties.[1] The project is aimed at the investigation and identification of different niobium(V) complexes that could potentially be utilized for the selective separation of niobium from tantalum. Interesting coordination chemistry is displayed by niobium(V) when utilising bidentate O,O’-donor ligands, such as acetylacetone and benzoylacetone.[2][3]. Different aspects of the solid state behaviour and solution chemistry were investigated and will be reported in this presentation. The study includes structural characterization by means of multi nuclear NMR spectroscopy, single crystal X-ray diffraction (see Fig. 1) and IR-spectroscopy. The various techniques are used to determine the different solid state coordination modes of the ligand spheres. UV/ Vis spectrophotometry and stopped flow techniques are utilized to construct a thermodynamic and kinetic reaction scheme for the various complexes of niobium.

Figure 1: Crystal structure of [NbCl(OMe)3(acac)]. [1] N. N. Greenwood, A. Earnshaw, Chemistry of the Elements, Butterworths/ Heinemann, Oxford, 1997, 976. [2] L. Herbst, R. Koen, A. Roodt, H.G. Visser, Acta Cryst., 2010, E66, m801 – m802. [3] L. Herbst, H. G. Visser, A. Roodt, T. J. Muller, Acta Cryst., 2011, E67, m1669 – m1670.

Keywords: Niobium, Tantalum, Separation

MS.C3.P.407 Copper Halides Complexes: Structural and Luminescent Properties Rita Hernandez-Molinaa, Amagoia Aguittextu-Comerónb, Javier González-Platasb, Ulises R. Rodríguez-Mendozac a Departamento de Química Inorgánica, Universidad de La Laguna, 38200 La Laguna, Tenerife (Spain). bDepartmento de Física Fundamental II, Universidad de La Laguna, 38200 La Laguna, Tenerife (Spain). E-mail: [email protected] The complexes of d10 metal complexes have received much research interest[1], [ 2] by their luminescent properties. In this work we have prepared two copper (I) halide complexes with N-donor ligands derived from pyridine with the aim to explore the luminescence properties as a function of pressure and temperature. The copper(I) halides complexes show a wide structural diversity thus giving structures with different nuclearity and dimensionality which is strongly affected by the reactions conditions such as temperature, solvent used for the crystallisation, ratio ligand/metal etc. Among these complexes those with the cubane structural type Cu4I4L4 has been the subject of much research. The complexes of the present communication have been prepared by reaction of CuI with 6-methylquinoline. Two different types of structures were obtained depending on the solvent used for the crystallisation. In the crystals obtained from toluene a dimeric structure of the type Cu2I2L2 was obtained with two iodide bridging ligands and four N-donor terminal ligands (Fig. 1). On the other hand for crystals obtained from acetonitrile a 1-D polymeric structure was obtained (Fig 1). These complexes have been characterised by X-Ray crystallography, elemental analyses and infrared spectroscopy. Finally the 1-D polymeric compound has been study as a function of pressure and temperature. Upon laser excitation at 406 nm and at ambient conditions the compound exhibits two bands, a weak band centred at 420 nm and a strong emission broad band around 590 nm that is usually assigned to 3 d10 → 3 d9 4s1 interconfigurational electronic transitions or to metal-to-ligand charge transfer.

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An array of functionalized (benz)imidazolium derivatives with CCC, CNC and NCN coordination pockets have been synthesized and characterized. N-heterocyclic carbene (NHC) Ag(I)- and Hg(II)complexes are readily formed in good to excellent yields from reactions of these ligand precursors with either Ag2O or Hg(OAc)2, respectively Depending on the stoichiometry of both salts and the metal source used, different coordination modes are seen. Nitrile functionalized complexes either adopt coordination with the carbene centres and the N terminal of the nitrile group (CMN) or coordination with only the NHCs. Mercury complexes showed interesting close interaction between the Hg metal centre with one carbon atom of the aryl linker in addition to coordination with two NHCs[1]. All complexes were characterized by NMR, microanalysis and X-ray crystallography. We also present the effective use of FT-IR spectroscopy as a reliable preliminary tool for the characterization of NHC complexes.

Poster Sessions MS.C3.P.409 A Series of Novel Multinuclear Heterometallic Strings with Rh and Ni Atoms Po-Hsien Ho,a Gene-Hsiang Lee,a Shie-Ming Peng,a,b aDepartment of Chemistry, National Taiwan University, Taipei, (Taiwan). bInstitute of Chemistry, Academia Sinica, Taipei, (Taiwan). E-mail: smpeng@ntu. edu.tw

Figure 1 [1] MV. W-W. Jam, K, K-W Lo, Chem. Soc. Rev. 1999, 28, 323-334. [2] P. Graham, R. D. Pike, Inorg. Chem. 2000, 39, 5121-5132.

Keywords: copper(I), halides, luminiscence

MS.C3.P.408 pH-Dependent CO2 Fixation by Copper(II) Complexes in the Framework of N8O2 Multidendate Ligand Yi-Hsueh Ho, and Jwu-Ting Chen*, Department of Chemistry, National Taiwan University, Taipei, (Taiwan). E-mail: jtchen@ntu. edu.tw The atmospheric CO2 fixation is of increasing interest from the point of view of environmental concerns. In this work, new N8O2 multidentate ligands are successfully synthesized and characterized. Their major structures contain three potential binding sites for copper(II) ions and the numbers of binding metal that bearing N2O8 ligand are controlled by pH value. The dinuclear copper(II) complex H46-PyPyCu2 is successfully synthesized and isolated under acidic condition. When additional copper ions and appropriate base are utilized, the dinuclear copper(II) complex can be turned to the trinuclear complex 6-PyPyCu3 [1],[2]. All of these complexes can easily take up carbon dioxide to form octanuclear carbonato complex 6-PyPyCu8 under suitable pH condition. All of these complexes are fully characterized by UV-vis, HR-ESI, and IR spectroscopy. In addition, H46-PyPyCu2 and 6-PyPyCu8 are also studied by single-crystal X-ray diffraction analysis (Scheme 1). Magnetic susceptibility measurements show that this new octanuclear copper compound of 6-PyPyCu8 are antiferromagnetically behavior.

In this presentation, novel tri- and pentanuclear heterometallic strings with Ni, Rh and oligo-α-pyridylamino ligands, dpa- and tpda2(dpa- = dipyridylamido; tpda2- = tripyridyldiamido), were synthesized and characterized. [1], [2] The d7-d7 dimetallic unit with single metalmetal bond, RhII-RhII, is easily broken-down at high temperature. Four heterometallic strings, RhNi2(dpa)4(NCS)2 (1), Rh2Ni(dpa)4(NCS)2 (2), Rh3Ni2(tpda)4(NCS)2 (3) and Rh2Ni3(tpda)4(NCS)2 (4), were obtained with the specific reaction conditions and shown in scheme 1, respectively. Compound (1)/(2) and (3)/(4) were separated by chromatography, respectively. ESI-MS spectra of (1) and (2) reveal the different Ni/Rh ratios and molecular weights, whereas the 1H-NMR spectrum of (1) and (2) displays four and eight independent signals revealing the point group of D4 and C4 symmetry, respectively. In X-ray diffraction analysis of (2), the disordered arrangements for Ni and Rh atoms along the metal string appear at terminal metal positions and the central metal position is fully occupied by Rh atom. In molecular structures of (3) and (4), the crystallographic disorder of metal atoms (Ni/Rh) located at two outer metal positions along the metallic axes are distinguished by electron density. The electron density of central metal atom belongs to a fully occupied Rh for (3) and a fully occupied Ni for (4), respectively. For cyclovoltagram spectra, compound (3) and (4) possess the first reversible singleelectron oxidation waves at the similar values, 0.39 V for (3) and 0.35 V for (4), but vary the first reversible single-electron reduction waves from -0.32 V for (3) to -0.77 V for (4). The magnetic property of (3) displays the antiferromagnetic trend from μeff = 2.45 B.M. at 300 K to μeff = 1.77 B.M. at 2 K. The magnetic behaviour of (4) shows the paramagnetic property in accordance with S = 1 of the terminal highspin Ni atom. [3]

Scheme 1

Scheme 1 [1] P. P. Y. Chen, R. B. G. Yang, J. C. M. Lee, S. I. Chan, Proc. Nat. Acad. Sci. 2007, 104, 14570-14575. [2] S. I. Chan, S. S.-F. Yu, Acc. Chem. Res. 2008, 41, 969-979.

Keywords: CO2 Fixation, tricopper

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[1] G.-C. Huang, I. P.-C. Liu, J.-H. Kuo, Y.-L. Huang, C.-Y. Yeh, G.-H. Lee, S.M. Peng, Dalton Trans., 2009, 2623–2629. [2] G.-C. Huang, M. Bénard, M.-M. Rhomer, L.-A. Li, M.-J. Chiu, C.-Y. Yeh, G.-H. Lee, S.-M. Peng, Eur. J. Inorg. Chem., 2008, 11, 1767–1777. [3] P. Kiehl, M.-M. Rohmer, M. Benard, Inorg. Chem., 2004, 43, 3151–3158.

Keywords: heteronuclear string complexes, extended metal atom chains

Poster Sessions MS.C3.P.410 Allosteric Cooperativity in the Protonation of Polyaromatic Tridentate Chelate Ligands Thi Nhu Y Hoang,a Laure Guénée,b Emmanuel Terazzi,a, Claude Piguet,a. aDepartment of Inorganic and Analytical Chemistry, University of Geneva, Geneva, (Switzerland). bLaboratory of Crystallography, University of Geneva, Geneva, (Switzerland). E-mail: Thi.Hoang@ unige.ch The successive protonation steps occurring in six-membered chelate ligands 2,6-bis(azaindol-yl)pyridine (L1) [1] and 2,6-bis(8-quinolin-yl)pyridine (L2) [2] (Figure 1) have been investigated and compared with the analogous 5-membered chelate 2,2’;6’, 2’’-terpyridine (L3) in the solid state and in solution. While L3 (

mercury lump (< 400 nm) at 0 ºC for 2 h in the presence of alkyne 3, alkyne photoaddition proceeded to generate single photoadduct 4 in 42 % yield (Fig. 1c). In the 1H NMR spectrum, the methylene protons of the coordinated alkyne 3 appeared as an AB quartet and the two Me4Cp ligands of adduct 4 were distinguished. Thus, alkyne 3 was bound to the Ru metal center with h2-coordination through terminal CO dissociation of ruthenium complex 2. Photoadduct 4 was a reaction intermediate stabilized within cage 1 and immediately converted to final product 5 after extraction from the cage with CH2Cl2. X-ray crystallographic analysis of product 5 revealed that alkyne migration occurred and that carbon-carbon bonds formed between the alkyne and carbonyl ligands to give the diruthenacyclopentenone framework.

) and particularly L1

) display strong affinities for protons, considerable

(

allosteric anti-cooperative processes (

)

prevent multi-protonations. On the contrary, L2 ( ) is significantly less eager for protonation, but the fixation of a second proton in [H2L2]2+ is driven to completion by positive cooperativity ). The molecular origin of this thermodynamic ( paradigm is addressed by a combination 1H NMR titration in organic solvent and by X-ray diffraction in the solid state.

[1] Garner, K. L.; Parkes, L. F.; Piper, J. D.; Williams, J. A. G. Inorg. Chem. 2010, 49, 476. [2] Jäger, M.; Eriksson, L; Bergquist, J; Johansson, O. J. Am. Chem. Soc. 2007, 72, 10227.

Figure 1. a) Self-assembled hollow cage 1. b) X-ray structure of 1•2. c) Schematic representation of alkyne photoaddition of 1•2.

Keywords: cooperativity, protonation, ligands

Keywords: host-guest complex, photoreaction, metal cluster

MS.C3.P.411

MS.C3.P.412

Alkyne Photoaddition of Dinuclear Ruthenium-Carbonyl Complexes Protected by a Self-Assembled Hollow Cage Shinnosuke Horiuchi,a Takashi Murase,a Makoto, Fujita,a,b aDepartment of Applied Chemistry, School of Engineering, The University of Tokyo, Tokyo, (Japan). bCREST, Japan Science and Technology Agency, Tokyo, (Japan). E-mail: [email protected]

Electrochemical Proof of Non-Innocent Character of Carbene Ligand Irena Hoskovcová,a Radka Metelková,a,c Tomáš Tobrman,b Dalimil Dvořák,b Jiří Ludvík,c aDepartment of Inorganic Chemistry, b Department of Organic Chemistry, Institute of Chemical Technology, Prague (Czech Republic). cJ. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Prague (Czech Republic). E-mail: [email protected]

In contrast with the rich photochemistry of mononuclear metalcarbonyl complexes, photochemical reactions of multinuclear metal carbonyls have been largely unexplored, due to the preferential photocleavage of metal-metal bonds into mononuclear metal radicals. Here we demonstrate that self-assembled hollow cage 1 maintains the dinuclear structure of [(Me4Cp)Ru(CO)2]2 (2) under UV light irradiation to effect terminal CO activation (Fig. 1a). Inclusion complex 1•2 was quantitatively obtained by suspending ruthenium complex 2 in an aqueous solution of cage 1 at 100 ºC for 2 h. X-ray analysis revealed the tight encapsulation of ruthenium complex 2 with a carbonyl-bridged cis configuration and efficient p-p interactions (3.3 Å) between the Me4Cp ligands of 2 and the panel ligands of cage 1 (Fig. 1b). When inclusion complex 1•2 was irradiated by a high-pressure

Molecular electrochemistry studies relationship between structure and redox potential of molecules together with electron transfer mechanism. The electronic structure of molecules can be followed by Linear Free Energy Relationship (LFER) approach [1]. According to the LFER, reduction (oxidation) potentials of a homologous substitution series depend on the Hammett constant σ, Eox(red)= ρ·σ + c, where the value of the reaction constant ρ reflects extent of interaction between the substituent and the reaction center, i.e. extent of electronic communication between these two sites. This approach, widely used in organic electrochemistry, can be applied to coordination compounds with large, electrochemically

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Figure 1: Structure of the polyaromatic tridentate chelate ligands.

Poster Sessions active ligands: redox non-innocent ligands [2]. Such complexes are characterized by presence of two electroactive centers located at different parts of the molecule.

We have investigated an extensive series of Fischer-type aminocarbene complexes of Cr, W and Fe of general formula (CO)nM=C(NR‘2)R, where R stands for p-substituted benzene ring or a heterocycle, M is either chromium or tungsten (n = 5), or M means iron (n = 4), R‘ stands for methyl or allyl group [3].

The aminocarbene complexes represent molecules with two redox active centres where the oxidation process allways takes part at the metal atom and the reduction proceeds on the carbene “non-innocent” ligand. As a result, the oxidation potential can be influenced by the metal itself and by the number of CO-ligands; on the other hand, the reduction potential is not sensitive to those parameters and it can be tuned by a substitution of the carbene moiety. Electrochemical results enable to evaluate relative importance of the following properties during oxidation or reduction: electron donating - withdrawing character of ligand substituents, π-bonding ability of ligands (CO, carbene, allyl), extent of π-electron conjugation, coordination number of the central metal atom and steric hindrance as some rearrangement takes place in course of the electron transfer. Results of bulk electrolysis are in accordance with the above description of the electronic arrangement of the molecules under study: In course of oxidation, the electron transfer is followed by release of CO. Reduction leads first to the splitting of the M=C bond, the M-CO bonds retain and undergo further rearrangement. Electrochemical results are in accordance with both computational and spectroscopic results. Examples of the studied molecules:

Acknowledgements: this work was supported by IGA grant, ICT Prague. [1] P. Zuman, Substituent Effects in Organic Polarography, Plenum Press, New York, 1967. [2] W. Kaim, B. Schwederski, Coord. Chem. Rev., 2010, 254, 1580. [3] I. Hoskovcová, J. Roháčová, D. Dvořák, T. Tobrman, S. Záliš, R. Zvěřinová, J. Ludvík, Electrochim. Acta 2010, 55, 8341.

Keywords: molecular electrochemistry, aminocarbenes, molecules with two redox centres

MS.C3.P.413 DRX and Thermal Studies on the UO22+ - 8 hydroxyquinoline System Doina Humelnicu,a Ionel Humelnicu,a Dan Maftei,a Costel Moldoveanu,a Gheorghita Zbancioc,a Sergiu Sovab aAlexandru Ioan Cuza University of Iassy, Iassy (Romania). bState University, Chisinau, (Moldova). E-mail: [email protected] Starting from literature data, stating that the metallic ions of uranium and thorium form numerous complex combinations, with good affinity for the ligands containing oxygen and nitrogen donor atoms, the present study investigates the thermal behaviour of the complexes formed by these two ions with 8-hydroxyquinoline. At the same time, the study resumes some previous investigations on the applications of the coupled TG-FTIR and MS method, viewed as a highly efficient technique for a correct establishment of the structurethermostability-degradation mechanism correlation. Study on the thermal behaviour of such compounds provides

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information on the temperature domain in which they are thermally stable, being therefore useful for the purification of residual waters. A good correlation was also established between structure and thermostability, estimated from the initial degradation temperatures by TG-FTIR. TG-FTIR analysis of the coordinative compounds, involving identification of the gaseous species resulted from degradation, by means of standard IR spectra, and of its results, correlated with those of mass spectroscopy analysis, permitted the design and elaboration of the most probable degradation mechanisms. Such specific and complex-through simultaneously-successive reactions-mechanisms reflect the influence of metal’s nature and of the structure of the respective coordinative compounds. Theoretical investigations upon the structure and reactivity of the studied compounds were employed with DFT (Density Functional Theory), and functional PBE0 (PBE1 PBE) - Perdew, Burke, Ernzerhof from the Gaussian 09 program package. The energetically-optimized electronic architecture which characterizes the complex structures investigated in their fundamental state was obtained by considering various bases of atomic orbitals for the atoms from the molecule. In this respect, 6-31+G was applied for the carbon and hydrogen atoms, and 6-31+G(d) for the oxygen and nitrogen atoms. For describing the metal, there have been used the effective core pseudopotential (ECP) (8s,8p,6d,5f,2g)/[5s,5p,4d,3f,2g] and the corresponding basic set (Stuttgart RLC -relativistic large core- ECP78MWB ANO). The investigated molecular complex was minima for level of theory used and positive frequencies were obtained. This was quite an expected result considering that, even if the two complexes have somehow different structures, the two nitrate anions from the thorium complex cannot be evidenced in the MS spectra as, out the numerous of fragments formed as a result of sample ionization, in the analyzer of the device will arrive only the fragments that maintain exclusively the positive charge (positive ions or positive radical ions). The MS spectra recorded show that the peaks corresponding to ligand (8-hq), resulted from the decomposition of complexes, have the same intensity, which indicates the existence of the same metal-ligand ratio in the starting complexes. Keywords: thermostability, pseudopotential, degradation

MS.C3.P.414 Template Synthesis of Monodisperse Titania Nanoparticles Within Self-Assembled Spherical Complexes Tatsuya ICHIJO,a Sota SATO,a Makoto FUJITA, aSchool of Engeering, The University of Tokyo, Tokyo, (Japan). bCREST. E-mail: [email protected] Properties of inorganic nanoparticles depend on their sizes and morphologies. Therefore, it is important to control their structures with a high degree of precision. The most-efficient methods used to prepare controlled-particles exploit hollow structures as endotemplates to sterically restrict their formation reactions. For example, micelles are commonly used, but their imprecise structure causes wide distribution of synthesized nanoparticles. On the other hand, we reported structurally well defined hollow spherical complex assembled from 12 metal ions and 24 organic ligands. By using the well defined interior of the spherical complex as endo-template, we have already reported synthesis of precisely monodisperse silica nanoparticles[1]. In this work, by using the spherical complex as an endotemplate, we succeeded in synthesizing highly monodisperse titania nanoparticles, whose function of photocatalyst is well known. Prepared titania nanoparticles are not only precisely size-controllable but also density-controllable.

Poster Sessions

Fig. 1 Synthesis of titania nanoparticles within M12L24 complexes

Fig. 2 a) AFM image of spherical cpmplexes 2 containing titania nanoparticles, b) TEM image of titania nanoparticles, c) MALDI-TOF MS spectrum of TiO2 nanoparticles (precursor 3 : 108 equiv.) [1] K. Suzuki, S. Sato and M. Fujita, Nature Chem. 2010, 2, 25–29.

Keywords: titania nanoparticle, template, spherical complex

MS.C3.P.415 Light Lanthanide Complexes with Crown Ether and Picrate Muhammad Idiris Saleh,a* Eny Kusrini,b Hoong Kun Fun,c aSchool of Chemical Sciences, Universiti Sains Malaysia, 11800 Penang (Malaysia). bDepartment of Chemical Engineering, Faculty of Engineering, Universitas Indonesia, Kampus Baru UI, 16424 Depok (Indonesia). cSchool of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia). E-mail: [email protected] Ternary lighter lanthanide complexes, [Ln(Pic)2(DC18C6)](Pic) for Ln = La, Ce were obtained by the reaction of [Ln(Pic)2(H2O)6] (Pic).6H2O with DC18C6 at 80 - 90°C, where DC18C6 = dicyclohexano-18-crown-6 and Pic = picrate anion. Both compounds have been characterized by single crystal X-ray diffraction, elemental analyses, fourier-transform infrared, and photoluminescence. X-ray diffraction showed that the both complexes had a ten-coordination number from the DC18C6 ligand in a hexadentate mode and the two Pic anions in bidentate modes, forming tetradecahedron geometries. Both complexe were crystallized in triclinic with space group P-1. The molecular organization was further stabilized by one-dimensional intra

and intermolecular hydrogen bonding. The rigid hexadentate cyclic DC18C6 ligand contains two cyclohexano substituents has controlled the formation of lanthanide complexes in the presence of bulky picrate anion. The PL spectra of both complexes display a green color at 534.6 nm due to the intraligand p-p of picrate anion. The nephelauxetic effect was observed in both complexes that defined as the red-shift emission at 534.6 nm compared to the free DC18C6 ligand at 511 nm. The PL spectra of [La(Pic)2(H2O)6](Pic).6H2O and [Ce(Pic)2(H2O)6] (Pic).6H2O salts and their complexes were similiar, indicating that the cyclic ligand did not contribute to enhance the green emission of the La(III) and Ce(III) complexes. Keywords: rown-6, photoluminescence, lanthanide complexes

MS.C3.P.416 Hemerythrin Type Diruthenium(III) Complexes with N,SAmbidentates Yohei Ido,a Takashi Fujihara,b Akira Nagasawa,a aDepartment of Chemistry, Graduate School of Science and Engineering, and b Comprehensive Analysis Center for Science, Saitama University, Saitama (Japan). E-mail: [email protected] The linkage isomerism is exhibited by ambidentate ligands with two or more different donor atoms depending on the oxidation state of metal centre and the environment such as the solvent. DMSO usually acts as a S-donor towards “soft” metal centre such as RuII, while as an O-donor toward “hard” RuIII [1]. Linkage isomerisation is often induced by light irradiation or redox reaction. In this study, we report on the redox-induced linkage isomerisation of m-oxidom-dicarboxylato diruthenium(III) ion with N- and S-donating ambidentates [RuIII2(m-O)(m-CH3CO2)2(2,2’-bpy)2L2]2+ (Figure 1, L = thiazole (1), 4-methylthiazole (2) or 2-methylthiopyridine (3)). Complexes with only N-bonded Ls (N,N-isomer), only S-bonded Ls (S,S-isomer) and one N-bonded and one S-bonded Ls (N,S-isomer) are possible. All the complexes were identified to be N,N-isomer by X-ray crystallography for 1 and by 1H NMR and UV-vis spectra for 2 and 3. Strong visible band is situated in the range 594–599 nm in CH3NO2, which is common for this class of complexes with N-donating terminal ligand and assigned to a transition from bridging oxido(pp) to Ru(dp) . The redox behaviour of those complexes was monitored by cyclic voltammetry (CV) in CH3NO2 containing 0.1 M Bu4NClO4. 1 showed a reversible reduction wave at E1/2 = -0.72 V vs. Fc/Fc+ assigned to N,N-isomer. 2 has one irreversible wave in the negative region, which indicates the decomposition of the reduced species RuIIIRuII. Isomerisation was not observed. On the other hand, 3 exhibited four peaks at the scan rate 0.5 V s–1 (Figure 2), suggesting that the N,Nisomer isomerises into the N,S-isomer. CV at slow scan rate (0.05 V s–1) shows one reversible reduction and one oxidation wave. The former and the latter are assigned to N,N-and N,S-isomer, respectively. The results suggest that linkage isomerisation of the N,N-isomer in RuIIIRuII state takes place rapidly to give N,S-isomer.

Figure 1. Diruthenium(III) complexes 1–3.

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Spherical complex 2 was self-assembled quantitatively from 12 Pd ions and 24 glucose-attached bidentate ligands 1 by mixing in DMSO. Spherical complex 2 had hydrophilic interior because of 24 accumulated glucose moieties. DMSO solution of complex 2 was diluted by twenty times with chloroform to make the outer environment of complex 2 hydrophobic. To this solution, 108 equivalent of precursor 3 was slowly added to form titania nanoparticles within the spherical complex 2 (Fig. 1). 1 H NMR signals of complex 2 were gradually broadened according to the additive amount of precursor 3, showing that titania particles grew up within spherical complex 2. The diameter of particles observed by AFM was consistent with that of spherical complex (Fig. 2a), proving the spherical framework was maintained after the formation of titania nanoparticle. The analysis of TEM images gave the diameter of titania nanoparticles to be 2.8 ± 0.2 nm (Fig. 2b), and MALDI-TOF MS analysis determined the polydispersity index of titania nanoparticles to be 1.017 (Fig. 2c). The size distribution of prepared nanoparticles was extremely narrow. In addition, the density of titania nanoparticles were controllable by the addition rate of the precursor.

Poster Sessions Fontecave, O. Hamelin, S. Ménage, Top Organomet. Chem. 2005, 15, 271. (b) O. Hamelin, M. Rimboud, J. Pécaud, M. Fontecave, Inorg. Chem. 2007, 46, 5354. [4] J. Hannedouche, G. J. Clarkson, M. Wills, J. Am. Chem. Soc. 2004, 126, 986. [5] D. Arquier, L. Vendier, K. Miqueu, J.-M. Sotiropoulos, S. Bastin, A. Igau, Organometallics 2009, 28, 4945.

Keywords: Ruthenium, h6/h5-arene ligands, amidines

MS.C3.P.418

Figure 2. Cyclic voltammogram (0.5 V s–1) of 3 (1 mM) in CH3NO2 with 0.1 M Bu4NClO4. [1] H. E. Toma, A. D. P. Alexiou, Electrochim. Acta, 1993, 38, 975-980.

Keywords: Oxido-dicarboxylato Bridged Diruthenium(III) Complex, Ambidentate Ligand, Linkage Isomerization

MS.C3.P.417 Functionalised Tethered h5/h6-Arene Ruthenium Complexes for Chiral at Metal Chemistry Igau Alain,a Kechaou Manel,a Vendier Laure,a Arquier Damien,a Bastin Stéphanie,a Miqueu Karinne,b Sotiropoulos Jean-Marc,b aCNRS, Laboratoire de Chimie de Coordination, Toulouse, (France). bIPREM, Université de Pau et des Pays de l’Adour, Pau (France). E-mail: alain. [email protected] Arene ruthenium(II) half-sandwich complexes I have been intensively investigated over the past decades and appear to be very efficient “precatalyst” in a large range of catalytic reactions. Nevertheless, the loss of the arene ring during a catalytic cycle is an unwanted side reaction encountered with this class of complexes which can lead to the deactivation of the active species. Moreover, it is noteworthy that the inversion barrier of the 16-electron catalytic active species is very low (less than 15 kcal/mol),[1] thus hampering their use as chiral-at-metal precatalyst in asymmetric catalysis. These two drawbacks can be circumvented by tethering the arene ring to the other ligands (X/L) in order to form thermally and configurationally stable chelate complexes to improve the enantioselectivity of asymmetric catalytic reaction.[2] Our studies evidenced that N-phosphanylamidine ligands allow the straightforward high yield synthesis in mild conditions of original tethered h6-arene ruthenium complexes such as A.[3] We also elaborated a synthetic process which leads, in gram scale one pot reaction, to the formation of unprecedented functionalized h5-arene ruthenium complexes (complex B). X-ray crystallographic analyses showed the structural adaptive behavior of the N-phosphino amidine ligands. The imino nitrogen atom of the amidine function behaves as a “universal joint”. The reactivity of the h6/h5-arene ruthenium complexes will be presented as well as joint DFT theoretical calculations.

Synthesis, Properties And Structure Of Nickel(Ⅱ) Tri-Mer and Nickel(Ⅱ) Mono-Mer Complexes Yuki Ishikawa,a Keiko Miyamoto,a Ernst Horn,a Yumi Ida,b Takayuki Ishida,b aCollege of Science, Rikkyo University (Japan). bDepartment of Engineering Science, The University of Electro-Communications (Japan). E-mail: [email protected] It is a peculiarity of nickel(Ⅱ)’s chemistry that complexes of one configuration can be easily converted to other configurations, usually accompanied by very contrasting color changes. The structure of halogen bridged nickel(Ⅱ) tri-mer complexes ([Ni3(tmen)3X4(OH)]X, X = Cl, Br (tmen =Me2NCH2CH2NMe2 )) are known. In this research, synthesis, structure and spectroscopic analysis of nickel(Ⅱ) fluoride tri-mer ([Ni3(tmen)3F4(OH)]F) and nickel(II) bromide mono-mer complexes ([Ni(tmen)(CH3CN)2(H2O)2]Br2 ) were conducted. Both tri-mer and mono-mer complexes are soluble in polar solvents, and chloride and bromide tri-mer complexes and bromide mono-mer complex show solvato- and thermochromism. However fluoride tri-mer complex does not show any chromotropic behavior. Figures 1 and 2 show UV-Visible absorption spectra of chloride tri-mer and fluoride tri-mer complexes.

Fig.1 Electronic spectra of [Ni3(tmen)3Cl4(OH)]Cl in EtOH and DCE measured at room temperature.

Fig.2 Electronic spectra of [Ni3(tmen)3F4(OH)]F in EtOH and DCE measured at room temperature.

The chloride-bridged trimeric complex [Ni3(tmen)3Cl4(OH)]Cl shows a ferromagnetic interaction. 2J/kB = 15.1(2) K. [1] Ruthenium in Organic Synthesis, S.-I. Murahashi (Ed.), Wiley-VCH, 2004. [2] B. Therrien, T. R. Ward, Angew. Chem. Int. Ed. 1999, 38, 405. [3] (a) M.

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Keywords: nickel(Ⅱ), structure analysis, Chromotropsm

Poster Sessions MS.C3.P.419

MS.C3.P.420

Reactivity of Cp*2Fe2S4 (Cp* = C5Me5) Toward Dimethyl Acetylenedicarboxylate Shohei Ito, Tsugiko Takase, Shinji Inomata, Faculty of Symbiotic Systems Science, Fukushima University, Fukushima (Japan). E-mail: [email protected]

Fundamental Properties of N-Substituted Pyridinium Boronic Acids with Strong Acidity Satoshi Iwatsuki,a Yusuke Asahori,a Ami Onishi,a Hidetaka Ohara,a Yuki Kanamitsu,a Eisuke Watanabe,b Koji Ishihara,b aDepartment of Chemistry, Konan University, Kobe (Japan). bDepartment of Chemistry and Biochemistry, Waseda University, Tokyo (Japan). E-mail: [email protected]. Much attention has been paid to complexation reactions of boronic acids (RB(OH)2) with diols including sugars in the areas of molecular design of saccharide recognitions as well as boron neutron capture therapy. The equilibrium constants of these reactions depend on the acidity of the solution and the optimal pHs of these reactions are expressed as an average of pKas of boronic acid and the diol ligand, i.e., pH = (pKaB + pKaL)/2. This equation suggests that the boronic acid having low pKaB would be preferable for the effective complex formation with saccharides (pKaL ~ 12) at neutral pH. In this study we carried out the detailed equilibrium and kinetic analyses to get the fundamental information on the properties of N-substituted pyridinium boronic acids, N-RPy+B(OH)2 [1]. The pKas of N-RPy+B(OH)2 (R = H, CH3, C3H7, C4H9, C5H11, C6H13) determined spectrophotometrically revealed that their boron centers have strong acidities, e.g., pKaBs of 3-HPy+B(OH)2 and 4-HPy+B(OH)2 were 4.4 and 4.0, respectively, and introduction of alkyl groups to the pyridine-N atoms had no influence on the acidities of the boron centers. On the contrary, introduction of the substituents to the pyridine-C atoms drastically decreased the boron acidities (pKaB > ~6). The equilibrium analyses of the complexation of 3- and 4-(N-R)Py+B(OH)2 (R = H, CH3) with saccharides exhibited that all these boronic acids are fructose-selective. The complex formation constant of 4-(N-CH3) Py+B(OH)2 with fructose (K1 = 6.5x10–2) predicts that the conditional formation constant K’ becomes maximum at pH 6–10 (K’ = 600 M–1), indicating that RPy+B(OH)2 can act as a fructose sensor at a wide pH range of neutral-alkaline solution. Although the detailed mechanism of saccharide recognition with N-RPy+B(OH)2 is still unclear due to its complicated reaction kinetics, the kinetic analyses on the complexation reactions with an oxygen-donor bidentate ligand, 4-isopropyltropolone (Hipt), afforded the fundamental information on its reactivity; it was found that all N-RPy+B(OH)2 (R = H, CH3) react with Hipt faster than their boronate ions RPy+B(OH)3–, which is consistent with our recent results [2]. Further, the rate constants for the complexation reactions of the trigonal boronic acids with low pKaB are larger than those with high pKaB, indicating that strongly acidic boronic acids such as N-RPy+B(OH)2 are kinetically as well as thermodynamically preferable for saccharide recognition.

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It has been known that the reaction of Cp*2Fe2(CO)4 (Cp* = C5Me5), elemental sulfur, and alkynes afford some mixed-ligand ironsulfur clusters [1]. In the reactions, iron-sulfur binuclear complex Cp*2Fe2S4 [2] plays as an intermediate. We tried the direct reaction of Cp*2Fe2S4 with an alkyne, dimethyl acetylenedicarboxylate (DMAD). Reaction between Cp*2Fe2S4 and DMAD (1:2 molar ratio) carried out in refluxing toluene for 24 h. A slica gel flash column chromatography was used for separating the products. The products were two novel diiron complexes 1 and 2 as well as two known mixedligand clusters 3 and 4 (eq 1). Both diiron complexes characterized by usual spectroscopic methods and X-ray structural analysis. The complex 1 consists of two Cp*Fe fragments unsymmetrically bridged by two dithiolene ligands (S2C2(CO2Me)2): Each dithiolene ligand has one bridging and one terminally coordinated sulfur atom. The iron-iron distance of 276.86(11) pm is consistent with a metal-metal bonding interaction. The complex 2 adopts almost the same structure with that of 1. This complex contains an unusal dithiolene-like ligand SOC2(CO2Me)2.

[1] S. Inomata, K. Hiyama, H. Tobita, H. Ogino, Inorg. Chem., 1994, 33, 5337. [2] H. Brunner, N. Janietz, W. Meier, G. Sergeson, J. Wachter, T. Zahn, M. L. Ziegler, Angew. Chem., Int. Ed. Engl., 1985, 24, 1060.

Keywords: Iron sulfur cluster, diiron complex, dithiolene ligand

Fig. 1. The abbreviations and structures of the reactants. [1] S. Iwatsuki, et al., J. Phys. Org. Chem., 2012, DOI: 10.1002/poc.2915. [2] S. Iwatsuki, et al., Inorg. Chem., 2007, 46, 354.

Keywords: boronic acid, complex formation, reaction kinetics

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Poster Sessions MS.C3.P.421 Oxometal Carboxylates: A Predesigned Platform for Modelling Prototypical MOFs Reactivity Toward Water and Donor Solvents Iwona Justyniak,a Janusz Lewiński,a,b Wojciech Bury,b Daniel Prochowicz,b Elżbieta Chwojnowska,b aInstitute of Physical Chemistry, Polish Academy of Sciences, Warsaw, (Poland). bDepartment of Chemistry, Warsaw University of Technology, Warsaw, (Poland). E-mail: [email protected] Oxo metal clusters decorated with carboxylate ligands are attracting a special attention as basic building units of a large class of prototypical microporous materials based on the tetranuclear cluster motif M4O(O2C-)6 linked by aromatic rings. The identification of possible interaction modes of prototypical M4O core with donor molecules may give a potential basis for the design of new catalytic systems incorporated into MOFs structure where host-guest interaction play a dominant role. We will report on a top-down relationship involving prototypical oxo-zinc and -aluminium carboxylates as the predesigned molecular platform for modeling the reactivity of prototypical MOFs towards water and donor ligands. For example, the isolation of stable cluster [Zn4(µ4-O) (O2CPh)6(H2O)(THF)]•2(THF) (2) provides a direct structural evidence for the initial interaction of H2O and THF molecules with the prototypical Zn4O core and undoubtedly demonstrates that the coordinated water molecule can be regarded as a molecular germ by attracting and binding other donor molecules with the formation of the second coordination sphere in Zn-MOFs and acting as a Brönsted acid assisted Lewis acid system.

trinuclear dithiolenes. New trinuclear dithiolene complexes with group 8 (RuII) and 10 (NiII and PtII) metals were synthesized (6-8). The cyclic voltamograms of 6 showed three successive reversible redox waves similar to those of 3-5. Furthermore, 6 and 7 exhibited intense electronic interaction through the phenylene bridge among the three dithiolene moieties during oxidation. Compound 8 exhibited intense absorption in the near-IR regions.[3]

Figure 1. π-conjugated trinuclear metalladithiolenes.

Figure 2. Cyclic voltammogram of 6 (0.5 mM) at a sweep rate of 0.1 Vs-1:a) reduction; b) Oxidation. [1] H. Nishihara, M. Okuno, N. Kogawa, K. Aramaki, J. Chem. Soc., Dalton Trans. 1998, 2651-2656. [2] Y. Shibata, B.-H. Zhu, S. Kume, H. Nishihara, Dalton Trans. 2009, 1939-1943. [3] T. Kambe, S. Tsukada, R. Sakamoto, H. Nishihara, Inorg. Chem. 2011, 50, 6856-6858.

Keywords: Metalladitholene, Mixed Valency, Trinuclear complex Keywords: oxo metal carboxylates, MOFs, structure

MS.C3-P-423 MS.C3.P.422 Expanding Family of Trinuclear Metalladithiolenes with p-Conjugated System Tetsuya Kambe, Satoru Tsukada, Ryota Sakamoto, Hiroshi Nishihara, Department of Chemistry, Graduate School of Science, The University of Tokyo (Japan). E-mail: [email protected] Metalladithiolenes are some of the best candidates for the integration of metals because of their unique electrochemical and photochemical properties. We previously reported the synthesis and properties of trinuclear metalladithiolene complexes of group 9 (CoIII, RhIII and IrIII) metals bridged by phenylene ring (1-5).[1, 2] For example, a cobaltadithiolene complex 1 exhibits three-step oneelectron reduction on metal center. And this trianionic form 13- displays peculiar magnetic properties depending on the matrix effect.[1] In this study, we achieved the expanding family of p-conjugated

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Heterodimetallic Complexes Bridged by 5-(2-Diphenylphosphinoethyl)tetrazolate Akihiko Kanayama, Yutaro Takehara, Keiko Kihara, Takayoshi Suzuki, Yukinari Sunatsuki, Graduate School of Natural Science and Technology, Okayama University, Okayama (Japan). E-mail: [email protected] In order to design and construct heterodinuclear transition-metal complexes having a characteristic functionality or reactivity, selection of a bridging ligand is essentially important. In this study, we have examined a possibility of 5-(2-diphenylphosphinoethyl)tetrazolate (dppetz–: Fig. 1) for such a bridging ligand, because it forms a stable six-membered chelate ring by coordination to the first metal center via the P and N1 atoms and, then, binds to

Poster Sessions the second metal center through either the N2, N3 or N4 atom. The ligand, dppetz–, was prepared from 2-cyanoethyldiphenylphosphine and sodium azide in the presence of certain metal-complex fragments, and the mononuclear complexes of [Co(Me2dtc)2(dppetz)] (1: Me2dtc– = N,N-dimethyldithiocarbamate), [Ir(ppy)2(dppetz)] (2: ppy– = 2-(2-pyridyl)phenyl) and [Pd(Me2dtc)(dppetz)] (3) were isolated. For preparation of dinuclear complexes, 1–3 were reacted with a Cp*M(L–L) fragment (M = RhIII or IrIII; L–L = 2,2’-bipyridine (bpy), ppy– or Me2dtc–), which was prepared in situ from the corresponding chloride complex and AgPF6 in methanol. The crystal structures of the isolated products were determined by X-ray analysis, and their molecular structures in solution were examined by NMR spectroscopy. It was revealed that the preferable bridging structures were largely dependent on the co-ligands in the first and the second metal fragments. For example, the Cp*M(bpy) fragment was bound to the N3 atom in the crystals of [Co(Me2dtc)2(m-dppetz)M(bpy)Cp*] (PF6)2•MeOH, while the corresponding Cp*M(ppy) fragment preferred the N4 coordination in [Co(Me2dtc)2(m-dppetz)M(ppy)Cp*]PF6•MeOH (Fig. 2). In solution, however, both kinds of dinuclear complexes exhibited bridging isomerization between the N3 and N4 coordination of Cp*M(L–L), but no evidence for the N2 coordination was observed. In the case of mononuclear IrIII complex 2 used as a building block, the N3-bridging isomer was unfavourable, as compared to the N4-bridging analogue. The steric interaction would give a main contribution for this observation, because a bulkier ppy ligand in 2 (than Me2dtc in 1) would give a severe steric hinderance with the Cp*M(L–L) fragment bound to the N3 atom. In contrast, when a sterically less demanding square-planar PdII complex 3 was used as a building complex, the formation of N2-bridging complexes, as well as the N3 and N4-bridging ones, were presumed by NMR spectroscopy.

molecules. Aggregation reduces the fluorescence lifetimes of the MPcs, most probably due to enhanced radiationless excited state dissipation and therefore lowers the quantum yields of the MPcs. Isomeric composition and the nature of the central metal ion affect the extent of aggregation. Fluorescence quantum yields of MPcs are largely affected by the nature of substituents and by aggregation behaviour. In this study, new phthalocyanines {H2Pc, Zn(II), Cu(II), Pb(II), Co(II) and Mn(III)} and bearing fluorescent substituents ligands, 3,3’-(1,1’-((4-methoxyphenyl)methylene)-bis-(naphthalene-2,1diyl))bis (oxy)-diphthalo nitrile and 4,4’-(1,1’-((4-methoxy- phenyl) methylene) bis (naphthalene-2,1-diyl))bis(oxy) diphthalo- nitriles were synthesized and characterized. Fluorescence properties of these compounds were investigated in solvents. The effects of peripheral and non-peripheral ring substituents on the photophysical parameters of MPcs derivatives were reported. Aggregation behaviour, fluorescence quantum yields of perip- herally and non-peripherally substituted derivatives were compared. The paramenters that affect quantum yields for the heavier central metals due to the heavy atom effect were also disscused.

[1] A.B.P. Lever, E.R. Milaeva, G.Speier; In C.C. Leznoff, A.B.P. Lever (Eds.), 465 Phthalocyanines: Properties and Applications, 1993 vol. 3, VCH, New York, 1-69. [2] M. Kandaz, O. Güney, F.B. Senkal, Polyhedron, 2009, 28(14), 3110-3114. [3] H. Lu, ZL. Xue, J. Mack, Z. Shen, X.Z. You, N. Kobayashi. Chem. Communn. 2010, 46, 3565-3567.

Keywords: phthalocyanines, aggregation, fluoroprobe

Keywords: tetrazolate, bridging isomers, steric interaction

MS.C3.P.424 Elucidation of Substituents Effecfts on Photophysical Properties of Fluoroprobe Attached Gemini Mono and Bunk-Type Phthalocyanines Mehmet Kandaza, Armağan Günsela, Orhan Güneyb, aDepartment of Chemistry, Sakarya University, 54140 Esentepe, Sakarya, Turkey, b Departmenet of Chemistry, Istanbul Technical Univer- sity, 34469, Istanbul, Turkey. E-mail:[email protected] The applications of new-type of metal-free (H2Pc) and metallophthalocyanines (MPcs) have expanded to areas such as photosensitizers in photodynamic therapy, chemical sensors and electrocatalysts [1-3]. Photodegradation is characterized by the decrease in the fluorescence intensity of the spectra without shift in maxima or formation of new bands, on exposure of MPcs to light. MPcs often form dimers or higher aggregates in solution. MPcs aggregate due to electronic interactions between rings of two or more

MS.C3.P.425 Elucidation of Coordination Complex Stoichiometry by Spectrofluorometric Titration Fehmi Karagöz,a Orhan Güney,a Mehmet Kandaz,b aDepartment of Chemistry, Faculty of Science and Letters, Istanbul Technical University, Istanbul (Turkey). bDepartment of Chemistry, Sakarya University, Sakarya (Turkey). E-mail: [email protected] Increasing attention has been given to the exploitation of a simple synthesis reagent and the development of a rapid, sensitive, and practical fluorescence analysis method to determine heavy metal ions [1]. Fluorescence detection with metal ion-responsive chemosensors offers a promising approach for simple and rapid tracking of metal ions for biological, toxicological, and environmental monitoring. Although heavy metal ions are relatively easy to chelate and detect in organic solvents, they are rather difficult to recognize directly in aqueous environments due to their strong hydrations. Concerns over toxic exposure to mercury provide motivation to explore new methods for monitoring aqueous Hg2+ ion from biological and environmental samples. Spectrofluorimetric methods for the determination of mercury are mainly based on the coordination of Hg2+ ion with fluorescent reagents have been examined for fluorescence Hg2+ detection [2].

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Fig. 2 Schematic drawings of Co–Ir dinuclear complexes bridged by dppetz– in (a) [Co(Me2dtc)2(m-dppetz)Ir(bpy)Cp*](PF6)2•MeOH and (b) [Co(Me2dtc)2(m-dppetz)Ir(ppy)Cp*]PF6•MeOH

Poster Sessions Although there are lots of examples of chemosensors for Hg2+ based on fluorescent quenching in organic or aqueous solution, there are less chemosensors with fluorescence enhancement for Hg2+ ion [3]. Therefore, development of selective chemosensors based on the fluorescence enhancement for Hg2+ ion in aqueous solution is the target of the many researchers. In this work, derivative of acridine (DAc) was synthesized and characterized by elemental analysis, FTIR, NMR spectroscopy. The photophysical properties of DAc were elucidated by UV-Vis and fluorescence measurements, and quantum yield in ethanol was calculated. We have found that DAc exhibited selective fluorescence enhancement upon titration with Hg2+ ion in buffered aqueous-ethanol solution at pH 6.0, whereas the fluorescence emission of DAc was quenched upon addition of other divalent transition metal ions. Further, pH-dependent change in fluorescent property of DAc was observed and pKa value was determined using data of integrated emission intensity versus pH. This unique property allows the evaluation of both pH of the solution and the selective recognition of Hg2+ ion among the other metal ions. In addition, the stoichiometry of complex between DAc and Hg2+ ion was elucidated applying by spectrofluorometric titration, and association constant was calculated. [1] J.F. Zhang, W.Y. Zhou, W.J. Yoon, J. S. Kim, Chem. Soc. Rev, 2011, 40,3416 [2] S. Güney, G. Yapar, O. Güney, G. Yıldız, Anal. Lett, 2009, 42, 2879. [3] L. Feng, Z. Chen, Sens. Actuators B, 2007, 122, 600.

Keywords: Fluorescence Complex stoichiometry

enhancement,

PET

chemosensor,

MS.C3.P.426 Synthesis and Electrochemical Characterization of New-type Mono and bis Phthalocyanines Sevgi Güneya, Armağan Günselb, Mehmet Kandaz,b aDepartment of Chemistry, Istanbul Technical University, Istanbul, (Turkey). b Department of Chemistry, Sakarya University, Esentepe, Sakarya, (Turkey). E-mail: [email protected] There have been continuous efforts to extend of the phthalocyanines (Pcs) chemistry in a variety of new technology fields including electrocatalysts, semiconductor devices, electrochromic display devices, liquid crystals, and as photosensitizers in photodynamic therapy (PDT)[1]. Metal phthalocyanines (MPcs) involving metal centers, such as Co(II), Fe(II), Ti(IV) and Mn(II) or Mn(III) have been receiving special interest due to their rich redox properties involving redox-active metal centers as well as their ring with conjugated 18 π-electron system [1-3]. The rich electrochemical properties of MPcs with redox active metal center are strongly affected by various factors such as the nature of solvent and supporting electrolyte, the presence or absence of oxygen and peripheral or nonperipheral substituents, due to their ability to coordinate axial ligands. In the present work, the redox and aggregation behaviour of the newly synthesized metallo and metal-free phthalocyanines bearing fluorescent substituents, 3,3’-(1,1’-((4-methoxyphenyl)methylene )-bis-(naphthalene-2,1-diyl))bis (oxy)-diphthalo nitrile and 4,4’-(1,1’-((4-methoxyphenyl) methylene) bis (naphthalene-2,1-diyl)) bis(oxy) diphthalonitriles were examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) on Pt in DMSO/TBAP. Compound H2Pc, Zn(II), Cu(II) and Pb(II) showed ligand-based redox reversible and irreversible couples while MnPcCl and Co(II) displayed ligand- and metal-based processes. Electrochemical parameters of the complexes, including the halfwave peak potentials (E1/2), ratio of anodic to cathodic peak currents (Ip,a/Ip,c), peak to peak potential separations (ΔEp) and the difference between the first oxidation and reduction processes (ΔE1/2)

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was investigated by CV. The influence of scan rate on peak potentials and peak currents of the complexes were also examined and reaction kinetics were determined by CV. [1] A. B. P. Lever, E. R. Milaeva, G. Speier in C. C. Leznoff and A.B.P. Lever (Eds.), 465 Phthalocyanines: Properties and Applications, 1993, vol. 3, VCH, New York, 1-69. [2] M. N. Yaraşir, M. Kandaz, A. Koca, Inorganica Chimica Acta, 2011, 365, 256–263. [3] H. Lu, Z. L Xue, J. Mack, Z. Shen, X. Z. You, N. Kobayashi, Chem. Communn., 2010, 46, 3565-3567.

Keywords: phthalocyanines, aggregation, electrochemistry

MS.C3.P.427 ‘Click’ Immobilisation of Ru(III) Complex Over Silica for Oxidation of Alcohols Under Mild Conditions in Aqueous Medium Ramasamy Karvembu,a Shanmugham Ganesamoorthy,a,b Manoharan Muthu Tamizh,a Kandasamy Shanmugasundram,b aDepartment of Chemistry, National Institute of Technology, Tiruchirappalli 620015, India, bSynthetic Chemistry Unit, Syngene International Ltd., Biocon Park, Bangalore 560099, India. E-mail: [email protected] The catalytic oxidation of alcohols to carbonyl compounds has been recognized to be of importance in organic transformations [1]. The silica immobilized Ru(III) catalyst for oxidation of alcohols in aqueous medium is found to have unique advantages in its simplicity and avoidance of cumbersome work up procedures. The silica immobilized Ru(III) catalyst have been characterized by solid state NMR, Inductively coupled plasma (ICP), FT-IR spectra, BET, SEM-EDX and solid state UV-Vis spectroscopy. The oxidation state of Ru was confirmed by EPR studies. The catalytic mechanism was also studied using solid state UV-Vis and FT-IR spectroscopy. The catalytic activity was optimized with different mole ratio, solvents, and temperatures using 1-pheylethanol as model system. The scope of the reaction is extended to various types of alcohols. The recycling of catalyst has also been tested.

Scheme 1 Silica immobilised Ru(III)-catalyzed oxidation of alcohols [1] K. Yamaguchi, N. Mizuno, Angew. Chem. Int. Ed. 2002, 41, 4538.

Keywords: oxidation, click chemistry, immobilisation

MS.C3.P.428 Cyclic Tetranuclear Rhodium(III) Complexes with Flexible Thyminate(2–) Bridges

Ayana Kashima,a Takayoshi Suzuki,a Yukinari Sunatsuki,a Akira Fuyuhiro,b aGraduate School of Natural Science and Technology, Okayama University, Okayama (Japan). bGraduate School of Science, Osaka University, Toyonaka (Japan). E-mail: [email protected]. ac.jp Cyclic polynuclear complexes (or metallamacrocycles) form a peculiar inner space, in which a specific molecule or ion may be recongnized selectively. In addition, if the constitutive metal

Poster Sessions fragments can be modified their properties by external stimuli, e.g., redox process or photo-irradiation, multi-functionality of the resulting complexes may be achieved [1]. In order to control the properties of the metallamacrocycles for the desired functionality, design of the bridging ligands are essentially important. Here, we deal with thyminate(2–) (thym2–) for a bridging unit to bind Cp*RhIII (Cp*= h5-C5Me5) fragments, because thym2– (which was formed by double deprotonation from one of the nucleobases: thymine) has four potential donor atoms (Fig. 1), giving a multiple patterns of bridging modes. A reaction of [(Cp*Rh)2(m-OH)3]OH and thymine in a 1:2 molar ratio in methanol was firstly examined. The yellow reaction mixture contained several Cp*Rh-containing products, confirming by 1H NMR spectroscopy, but the addition of NaPF6 or Dy(NO3)3•6H2O gave a selective formation of orange crystals of compound 1 (NaPF6 adduct) and compound 2 (Dy(NO3)2+ adduct). The crystal structures of 1 and 2 were determined by X-ray. In both compounds four Cp*RhIII fragments and four bridging thym2– ligands form a cyclic tetramer, in which a cation (Na+ or Dy3+) is incorporated. However, it is interesting that the bridging modes of thym2– are different from each other (as shown schematically in Fig. 2); in 1 it coordinate to RhIII via N1, O2 and N3, while in 2 via N1, N3 and O4. Owing to the different bridging modes of thym2–, the shape of the cages constructed from Cp*Rh4(mthym)4(Na+ or Dy3+) was also different, where a Et2O molecule and a NO3– anion were included in compounds 1 and 2, respectively. The cyclic tetranuclear cages con-taining a cation, Cp*Rh4(mthym)4Na+ or Dy3+), was maintained in solution, as confirmed by 1H NMR spectroscopy or ESI-MS. Also, the conversion of com-pound 1 to 2 by addition of Dy(NO3)3 in methanol was also examined. These results will also be presented.

A series of vanadyl complexes [Tp*VOL] were Tp* is hydrotris(3,5dimethylpyrazolyl)borate and L=1-R-benzoyl-disubstituted-thiourea (HL) with the general formula of [R3-Ph(CO)NH(CS)NR1R2], where R1 and R2 = alkyl or aryl groups and R3 = F, Cl, Br, OCH3, CH3, NO2 and Ph functional groups has been synthesized, characterized, and tested for bioactivity as potential antifungal and anticancer agents. The complexes were characterized on the basis of elemental analysis, mass spectrometry, X-ray crystallography, spectroscopy, cyclic voltammetry, magnetic susceptibility and electron paramagnetic resonance. Stability of the vanadyl complexes was enhanced by the presence of the tripodal Tp* ligand and the chelating HL ligand, whichcoordinates via the O,Sdonor atom. The electron density around the 1-R-benzoyl-disubstitutedthiourea coordination sphera is highly delocalized on the thiocarbonyl fragment. X-ray structure of the complexes shows the vanadium centre in a pseudo-octahedral configuration formed by the bidentate O,S1R-benzoyl-disubstituted-thiourea ligand occupying the cis equatorial positions, two N atoms of the tridentate N,N’,N’’ Tp* occupy the other cis equatorial positions and the third Tp* N atom is trans to the terminal oxo. The electronic spectra of the vanadyl complexes exhibited multiple d-d transitions typical for a distorted octahedral geometry. Magnetic moments of 1.6-1.7 BM confirmsa d1 configuration for the V(IV) centre. The solution and solid state EPR spectra of the complexes are consistent with a distorted octahedral vanadyl with g-values in the ranges of 2.187–1.79. The cyclic voltammogram of the vanadyl complexes revealed only one quasi-reversible oxidation wave for V(IV)/V(V) couples but spectroelectrochemical study showed the molecules was fully reversible at -20°C. A DFT calculation shows the HOMO is significantly vanadyl based with some contribution from the oxo and 1-R-benzoyl-disubstituted-thiourea ligand, however, the LUMO is mainly metal-based. The complexes have been tested for their biological activities against selected pathogens and cancer cell lines and showeda moderate activity against pathogenic bacteria and fungi. Cytotoxic test carried out using MTT assay showed the complexes were not toxic to the Chang liver cells at high concentration. Three vanadyl complexes have been tested in vitro for their anticancer activities assay, which revealed the complexes were active against human hepatocellular carcinoma cell line (HepG2) at high concentration.

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[1] K. Severin, Chem. Commun., 2006, 3859–3867.

Keywords: metallamacrocycles, tetramer, cation inclusion

MS.C3.P.429 New Vanadyl Complexes with Mixed O,N and S Donor Ligands: Synthesis, Structural and Electronics Properties Mohammad B. Kassim,a,b & Aisha A. Al-abassi,a aSchool of Chemical Sciences & Food Technology, Faculty of Science & Technology, Universiti Kebangsaan Malaysia, Selangor (Malaysia). bFuel Cell Institute,Universiti Kebangsaan Malaysia, Selangor (Malaysia). E-mail: [email protected]

Fig. 1. Vanadyl complexes with Tp* and 1-R-benzoyl-disubstituted-thiourea.

Keywords: vanadyl, pyrazolylborate, thiourea

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Poster Sessions MS.C3.P.430 Tricyclic Chelate Ni(II) Complexes Derived from an Aminomethylene-malondialdehyde Hamid Khaledi,a Hapipah Mohd Ali,a Marilyn M. Olmsteadb a Department of Chemistry, University of Malaya, Kuala Lumpur (Malaysia). bDepartment of Chemistry, University of California, Davis, CA (USA). E-mail: [email protected]. Two tricyclic chelate nickel complexes were isolated from the reaction of an aminomethylene-malondialdehyde, i.e. 2-(diformylmethylidene)3,3-dimethylindole with o-phenylenediamine in the presence of Ni2+ ion. The ligands in these complexes behave in N4-tetradentate manners giving rise to a neutral and a cationic metal complex. The compounds would appear to be the uncyclized intermediates in the synthesis of the related dibenzotetraaza[14]annulene. The reaction of 2-(diformylmethylidene)-3,3-dimethylindole with o-aminophenol resulted in the formation of the related salentype ligand. Upon the reaction with Ni2+ ion, the ligand underwent deprotonation at its hydroxyl groups to act as a dianionic N,N’,O,O’tetradentate chelate. The synthesized nickel(II) complexes show distorted squareplanar coordination geometry as revealed by single crystal X-ray crystallography.

In this study, we tried anodic shift of the redox potential of Ru complex containing NAD+/NADH ligands with an intention of an increase a hydride donor ability of the complex. At first, we changed ancillary ligands from two bpy ligands to 2-picolinate (pic) ones. [Ru(pic)2(pbn)] (2) showed Ru(III)/Ru(II) redox potential at 0.55 V vs. SCE, which was 0.75 V negative than that of 1. On the other hand, the reduction potential of pbn ligand in 2 only -0.15 V negative than that of 1. These facts indicate that electron donor ability of ancillary ligands hardly effects on pbn redox potential. We also prepared a new NAD+/NADH lidand, benzo[b] pyrido[3,2-f][1,7]phenanthroline (bpp). Ru(III)/Ru(II) redox couple of [Ru(bpy)2(bpp)]2+ (3, Figure 1b) was observed at 1.23 V, which was almost same as complex 1. On the other hand, bpp/bpp-• was ca. -0.3 V negative than that of 1. Photo irradiation of 3 in the presence of trietylamine and water yielded the reduced form of 3, [Ru(bpy)2(bppHH)]2+. We will discuss the hydride donor ability of those electrochemical and photochemical reduced Ru complexes.

Figure 1 (a) [Ru(bpy)2(pbn)]2+ , (b) [Ru(bpy)2(bpp)]2+. [1] T. Fukushima, T. Wada, H. Ohtsu, K. Tanaka, Dalton trans. 2010, 39, 1152611534. [2] T. Koizumi, K. Tanaka, Angew. Chem. Int. Ed. 2005, 41, 5891-5894.

Keywords: Ru complex, NAD+/NADH ligand, Redox potential

MS.C3.P.432 Synthesis, Structures and Dynamic Behaviour of AnthyridineCoordinated Transition Metal Complexes Take-aki Koizumi, Shota Hirakawa, Takanori Fukushima, Chemical Resources Laboratory, Tokyo Institute of Technology (Japan). E-mail: [email protected] Keywords: tetradentate crystallography

chelate,

Ni(II)

complex,

X-ray

MS.C3.P.431 Redox Control of Ru Complex Bearing Various NAD+/NADH Model Ligands Katsuaki Kobayashi, Koji Tanaka, Institute for Integrated CellMaterial Sciences, Kyoto University, Kyoto (Japan). E-mail: kkobayashi@icems. kyoto-u.ac.jp Conversion from photo- and electric energy to chemical one as a stockable energy would greatly contribute to maintain global environments. We have reported that Ru polypyridyl complexes bearing NAD+/NADH functionalized ligands (2-(2-pyridyl)bonzo[b]1,5-naphthylidine, pbn) and their photo active characters.[1][2] [Ru(bpy)2(pbn)]2+ (1, Figure 1a) undergoes not only electrochemical but also photochemical proton coupled two-electron reduction to afford [Ru(bpy)2(pbnHH)]2+, similar to the NAD+/NADH redox reaction.[1] [2] NADH framework in Ru-pbnHH complex is specially interested in the viewpoints of a possible renewable hydride donor aimed at natural energy-convertor. However, it showed weak hydride donor ability probably due to quite positive oxidation potential of NADH moiety.

C338

Transition metal complexes showing dynamic behaviour have been attracted much attention. There have been many reports for “dynamic complexes”. 1,8-Naphthyridine (napy) is one of the ligands that shows dynamic behaviour such as 1,3-haptotropic shift and change of the coordination modes between monodentate and bidentate. The 1,3-diazine structure, which is contained in napy, is useful to compose the dynamic complex and application to molecular switching devices. 1,9,10-Anthyridine (anth) is an aromatic compound which has a three pyridine ring-fused structure. If anth is used as a ligand of transition metal complexes, it is expected that change of the coordination modes like napy and more expanded haptotropic shift are shown. However, there have been no reports about anth-coordinated transition metal complexes. In this study, we prepared new Ru(II) complexes having anthyridine derivatives as a ligand, and clarified their structures and chemical properties. Dynamic behaviour of the complexes in the solution was also investigated. Dibenzoanthyridine derivative dbanth (L1) was prepared by the reaction of 3,5-diiodo-2,6-diaminopyridine with 2 equiv of 2-formylphenylboronic acid according to the literature. Anthyridineligated Ru(II) complex [Ru(L1)(bpy)2](PF6)2 ([1](PF6)2, bpy = 2,2’-bipyridyl) was synthesized by the reaction of AgPF6-treated [RuCl2(bpy)2] with L1 in CH3OCH2CH2OH.

Poster Sessions

Keywords: Ruthenium, Anthyridine, Dynamic behavior

MS.C3.P.433 Synthesis, Characterization and Photocatalytic Properties of self-Assembled Silver(I) Complexes With Novel Bis(Terpyridine) Ligands Michał Kołodziejskia, Monika Wałęsa-Choraba, Maciej Kubickia, Grzegorz Kądziołkab, Beata Michalkiewiczb, Violetta Patroniaka* a Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60780 Poznań, Poland, bThe West Pomeranian University of Technology, Szczecin, Poland. E-mail: [email protected] The main and perspective direction of supramolecular chemistry is the phenomenon of self-organization, which gives us almost unlimited possibilities to obtain a variety of architectural structures resulting from the various types of interactions between substrates. After successful synthesis of grid-type [1, 2] and helical [3] complexes of silver(I), we attempted to prepare silver(I) complexes with new N6-donor ligands (L1 and L2). [Ag2L12](CF3SO3)2∙H2O is active photocatalyst of methylene blue degradation under UV-Vis and sunlight irradiation [4]. Photocatalytic investigation of polymeric complex [AgL2]n(CF3SO3)n is in progress [5].

Structure of [Ag2L2](CF3SO3)2∙H2O

The author’s participation in the conference is co-financed by the European Union from the European Social Funds The Human Capital Operational Programme, Sub-measure 4.1.2. [1] V. Patroniak, A.R. Stefankiewicz, J.-M. Lehn, M. Kubicki, Eur. J. Inorg. Chem. (2005) 4168. [2] V. Patroniak, J.-M. Lehn, M. Kubicki, A. Ciesielski, M. Wałęsa, Polyhedron 25 (2006) 2643. [3] A.R. Stefankiewicz, M. Wałęsa, P. Jankowski, A. Ciesielski, V. Patroniak, M. Kubicki, Z. Hnatejko, J.M. Harrowfield, J.-M. Lehn, Eur. J. Inorg. Chem. (2008) 2010. [4] M. Wałęsa-Chorab, V. Patroniak, M. Kubicki, G. Kądziołka, J. Przepiórski, B. Michalkiewicz, J. Cat., accepted. [5] M. Kołodziejski, M. Wałęsa-Chorab, V. Patroniak, M. Kubicki, G. Kądziołka, B. Michalkiewicz, unpublished data.

Keywords: self-assembly, silver(I) ions, photocatalysts

MS.C3.P.434 E-Selective Reactivity in Heterodinuclear η1:η2-Crotylplatinummanganese Complexes Sanshiro Komiya, Toshiki Nakano, Shun, Saito, Nobuyuki Komine, Masafumi Hirano, Department of Applied Chemistry, Tokyo University of Agriculture and Technology, Koganei, Tokyo (Japan). E-mail: [email protected] Hetereodinuclear organotransition metal complexes attract attention in relation to unsolved cooperative nature of two different metals in bimetallic catalysis. We have synthesized series of such heterodinuclaer complexes and found interesting features such as organic group transfer along transition metals, enhanced CO insertion, stereo-selective C-S bond cleavage reactions in addition to catalyses promoted by these complexes [1]. Among them allylplatinum-cobalt complexes showed very unique E-form selective reactions. In this presentation, we would like to focus on this E form-selective crotyl group transfer reaction and stereochemical nonrigidity of η1:η2crotylplatinum-manganese (and other metal) complexes. Mechanistic insights on this unique E-selective reactivity will be discussed.

P.MS.C3

The structure of [1](PF6)2 was determined by X-ray crystallography as well as 1H-NMR spectroscopic study. From the X-ray diffraction study, it is clarified that the dbanth ligand in [1](PF6)2 is coordinated to the Ru center as a bidentate fashion. The 1H-NMR spectrum measured in acetone-d6 also supports the structure. The solution color of [1](PF6)2 in acetone-d6 is orange-brown. On the other hand, when [1](PF6)2 was dissolved in acetonitrile-d3, the solution color showed yellow. This result suggests that the structure of [1](PF6)2 was changed in an acetonitrile solution. To determine the molecular structure of CH3CNtreated [1](PF6)2, [1](PF6)2 was recrystallised from MeCN-Et2O to obtain good crystals for X-ray crystallographic study. From the result of X-ray analysis, it is clear that the dbanth ligand in the complex, [2](PF6)2, obtained from the CH3CN-Et2O solution is coordinated to the Ru center as a monodentate mode, and one CH3CN molecule is coordinated to Ru. The 1H-NMR spectrum of the complex measured in acetonitrile-d3 also supports the monodentate coordination structure. When the 1H-NMR of [2](PF6)2 was measured in acetone-d6, the signals assigned to [2](PF6)2 were not observed but those of [1](PF6)2 appeared. These results suggest that the coordination modes of the dbanth ligand can change by addition/elimination of CH3CN. UV-vis and emission spectra, electrochemical properties, and details of the dynamic behaviour of the complexes will be also reported.

Ligand L1and L2

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Poster Sessions [1] S. Komiya, Coord. Chem. Rev., 2012, 256 ,556-573.

Keywords: Heterodinuclear Complex, E-Crotyl Selective Transfer, Reductive Elimination

MS.C3.P.435 Multielement Organometallic Complexes Based on Rare- and Alkaline-Earth Metals Sergey N. Konchenko,a Peter W. Roesky,b Manfred Scheer,c aNikolaev Institute of Inorganic Chemistry SB RAS, Novosibirsk (Russia), Institute of Inorganic Chemistry, University of Regensburg, Regensburg (Germany), cInstitute of Inorganic Chemistry, Karlsruhe Institute of Technology, Karlsruhe (Germany). E-mail: [email protected] In the well-developed chemistry of organometallic transition metal (TM) complexes the compounds in which, besides M-C bonds, the metals are bonded with different main group elements are substantially evaluated as really common. In contrast to TM, only compounds with N- and O-donor ligands are well-represented among the rare- and alkaline-earth metals (RAM). Analysing CCDC structural data one may see that even complexes with P- and S-donor ligands are not really numerous, and heavier elements are represented just by solitary examples. A majority of the examples for group 13 elements are the compounds containing RAM and E at a distance tolerated to M-E bond, but it is supported by bridging ligands, so the question about real bonding is quite controversial. Recently we have obtained a set of complexes in which low valent group 13 metal compounds serve as ligands towards RAM (Scheme 1): it has been found that reactions of [Cp*Al]4 and [Cp*Ga]6 with [Cp*2M] lead to the compounds with donor-acceptor M–E bonds. Organometallic polyphospide and chalcogenide transition metal complexes are very interesting and actively investigating “building blocks” for assembling coordination polymers and supramolecular compounds of unusual structure. Until recently molecular polyphosphide complexes of RAM were unknown. We have reported about the first example of them: [(Cp*2Sm)4P8] obtained as a result of P4 reduction by [Cp*2Sm(THF)2]. It has been found also that high reduction potential of [Cp*2Ln(THF)2] (Ln = Sm, Yb; Cp* = h5-C5Me5) can serve as a driving force for creation of unusual mixed-metal chalcogenide clusters. Thus the reactions of [Cp*2Ln(THF)2] with [Fe2S2(CO)6] lead to reductive rearrangement of the Fe2S2 core and formation of the “wheel” heterometallic clusters where Ln is connected with the cluster core by Ln–S bonds and iso-carbonyls. For instance, [Fe6S6(CO)12(SmCp*2)]. Herewith we report about syntheses and structural features of the above mentioned and related heterometallic polypnictide and polychalcogenide complexes [1-5]. Synthetic approaches are discussed in comparison with the other ones developed recently and used for synthesis of new Ln- and An-containing complexes.

MS.C3.P.436 Reactions of Nitrile on Ruthenium Complexes Having Pyridinecontaining Ligands Taro Kono, Toshiyuki Itohiya, Sohei Fukui, Hirotaka Nagao, Department of Materials and Life Sciences, Sophia University, Tokyo (Japan). E-mail: [email protected] Reactions and conversions of nitrile to afford corresponding amide have been investigated using metal complexes as catalysts. We reported reactions of acetonitrile coordinated to the nitrosylruthenium complex having 2,2’-bipyridine (bpy) with H2O and CH3OH [1]. Reactivity of the acetonitrile ligand can be controlled by co-existing ligands such bpy and 2-pyridine-carboxylato (pyc). In this work, syntheses and reactions of cis-[Ru(NO)(RCN)(pyc)2]ClO4 (R = Ph, CH3) and cis-[RuIICl-(CH3CN)(pyc)(bpy)] with H2O, alcohol, and amine as nucleophiles were investigated. A reaction of [Ru(NO)(PhCN)(pyc)2]ClO4 with H2O at room temperature afforded benzamide complexes, [Ru(NO)-(PhCONH2) (pyc)2]ClO4, existing as an equilibrium mixture of amidato, imide, and imidato complexes in aqueous solution (Scheme 1). The X-ray single crystal structural analysis confirmed the amidato-type structure. Benzonitrile was catalytically converted into benzamide by the complex (Scheme 2). Reactions of [Ru(NO)(CH3CN)-(pyc)2]ClO4 in a 1: 1 acetonitrile / R’OH (R’= CH3, C2H5, C3H7, C4H9) mixed-solvent under refluxing conditions afforded a yellow imidoester complex, [Ru(NO)(CH3C(OR)NH)(pyc)2]ClO4. [Ru(NO)(CH3CN)-(pyc)2]ClO4 was also reacted with propylamine at room temperature to afford an amidine complex, [Ru(NO)(CH3C(C3H7NH)NH)(pyc)2]ClO4. These proceeded via a nucleophilic attack to the carbon atom of acetonitrile coordinated to the ruthenium center (Scheme 2). We would like to discuss the reactivity of nitrile ligand by reactions of [RuIICl(CH3CN)(pyc)(bpy)] and bis(pyc)-type benzonitrileruthenium complex, [Ru(NO)(C6H5CN)(pyc)2]ClO4, with alcohol and propylamine.

Scheme 1. Equilibrium between amide, amidato, imide, and Scheme 1. imidato complexes

[1] T. Li, J. Wiecko, N.A. Pushkarevsky, M.T. Gamer, R. Köppe, S.N. Konchenko, M. Scheer, P.W. Roesky, Angew. Chem. Int. Ed., 2011, 50, 94919495. [2] S.N. Konchenko, T. Sanden, N.A. Pushkarevsky, R. Köppe, P.W. Roesky, Chem. Eur. J., 2010, 16, 14278-14280. [3] S.N. Konchenko, N.A. Pushkarevsky, M.T. Gamer, R. Köppe, H. Schnöckel, P.W. Roesky, J. Am. Chem. Soc., 2009, 131, 5740-5741. [4] M. Wiecko, P.W. Roesky, P. Nava, R. Ahlrichs, S.N. Konchenko, Chem. Comm.., 2007, 927-929. [5] M.T. Gamer, P.W. Roesky, S.N. Konchenko, P. Nava, R. Ahlrichs, Angew. Chem., Int. Ed., 2006, 45, 4447-4451.

Keywords: synthesis, lanthanides, mixed-metal complexes

Scheme 2. Reactions of [Ru(NO)(RCN)(pyc)2]ClO4 [1] H. Nagao, T. Hirano, N. Tsuboya, M. Mukaida, T. Oi, and M. Yamasaki, Inorg. Chem., 2002, 41, 6267.

Keywords: 2-pyridinecarboxylato, nitrile, nitrosyl ligand

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Poster Sessions MS.C3.P.437

MS.C3.P.438

In Situ Ligand Esterification in Alcohols with Cobalt(II) Chloride Bojan Kozlevčar,a Marta Kasunič,a Nives Kitanovski,a Jan Reedijk,b,c a Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana (Slovenia). bLeiden Institute of Chemistry, Leiden University,, Leiden, (The Netherlands) c Department of Chemistry, King Saud University, Riyadh, (Saudi Arabia). E-mail: bojan.kozlevcar@ fkkt.uni-lj.si

HFEPR and Magnetic Studies of Three-Coordinate Vanadium(II) Complexes J. Krzystek,a A. Ozarowski,a B. L. Tran,b B. Pinter,b A. J. Nichols,b C.H. Chen,b M. Singhal,b M. Pink,b H. Park,b O. P. Lam,c J. Telser,d M.H. Baik,b K. Meyer,c D. J. Mindiola,b aNational High Magnetic Field Laboratory, Florida State University, Tallahassee (USA), bDept. of Chemistry, Indiana University, Bloomington (USA), cDept. of Chemistry and Pharmacy, University of Erlangen-Nürnberg (Germany), dDept. of Biological, Chemical and Physical Sciences, Roosevelt University, Chicago (USA). E-mail: [email protected] Vanadium can access a wide range of oxidation states, many of which are paramagnetic. These include V(IV) (3d1, S =1/2), which has been well-studied by Electron Paramagnetic Resonance (EPR), as well as states with multiple unpaired electrons. The latter often need to be studied by High-Frequency and -Field EPR (HFEPR) due to large zero-field splitting. Our attention was recently drawn to V(II) (3d3, S =3/2), which had hitherto not been studied by HFEPR. V(II) is best known in vanadocene, Cp2V (Cp = cyclopentadiene monoanion) but new synthetic work has led to the preparation of V(II) complexes with a wide variety of ligands, such as nacnac, the β-diketiminato ligand. The motivation for the synthetic work has been a search for an efficient medium to activate and cleave the triple bond of atmospheric nitrogen as well as convert it into ammonia. We will concentrate on a “masked” three-coordinate vanadium(II) complex, [(nacnac)V(Ntol2)], where nacnac = RN=C(CH3)CH=C(CH3) NR monoanion, with R = 2,6-diiso-propylphenyl, and tol = tolyl (CH3C6H4). In this complex, a tethered arene moiety protects the unsaturated and highly reducing V(II) center, which can be unmasked for further reactivity studies.[1] More recently, a bona fide planar three-coordinated V(II) complex [(nacnac)V(ODiiP)] where ODiiP = 2,6-diisopropyl-phenoxide (see Figure below), was also prepared and successfully investigated.[2] We will present and discuss HFEPR and magnetometry results that can be interpreted and related to the electronic structure of the V(II) complexes and hence are relevant for the reactivity studies.

Figure 1: The methyl ester (left) and the ethyl ester (right) of the initial ligand Hbdmpza in tetrahedral [CoLCl2].

We thank R. de Gelder for some of the structural data. [1] S. Trofimenko, Scorpionates, The Coordination Chemistry of Polypyrazolylborate Ligands, Imperial College Press, 2005. [2] C. Pettinari, R. Pettinari, Coord. Chem. Rev. 2005, 249, 663-691. [3] N. Burzlaff, Advances in Inorganic Chemistry, 2008, 60, 101-165. [4] B. Kozlevčar, T. Pregelj, A. Pevec, N. Kitanovski, J. Sánchez Costa, G. van Albada, P. Gamez, J. Reedijk, Eur. J. Inorg. Chem. 2008, 4977–4982.

[1] B. L. Tran, M. Singhal, H. Park, O. P. Lam, M. Pink, J. Krzystek, A. Ozarowski, J. Telser, K. Meyer, D. J. Mindiola, Angew. Chem. Int. Ed. 2010, 49, 9871-9875. [2] B. L. Tran, B. Pinter, A. J. Nichols, C.-H. Chen, J. Krzystek, A. Ozarowski, J. Telser, M.-H. Baik, K. Meyer, D. J. Mindiola, J. Am. Chem. Soc., submitted.

Keywords: bdmpza, ester, cobalt chloride

Keywords: vanadium(II), magnetic properties, HFEPR

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P.MS.C3

The design of model complexes for metalloenzymes is amongthe topical areas of coordination chemistry. Hbdmpza (bis(3,5dimethylpyrazol-1‑yl)acetic acid) as polypyrazolyl donor ligand represents an important member of the family of tridentate scorpionates exhibiting facial coordination mode. [1,2] Anionic bdmpza, by loss of H+ from Hbdmpza, may act as a tridentate ligand (scorpionate), but other coordination modes have also been reported. [3] Usually, the starting ligand Hbdmpza/bdmpza is stable under the reaction conditions. Recently, we noticed the ligand esterification in methanol with CuCl2 as a starting species giving new N,N-didentate Mebdmpza ligand upon coordination to the metal copper(II) center. [4] Following these results, we tried several experiments with the cobalt(II) ion in several solvents and with several counter-ions. It proved again, that the MCl2 starting species enables Hbdmpza esterification, giving the methanol as well as the ethanol ester, Mebdmpza and Etbdmpza, respectively. Their mononuclear structures [Co(Mebdmpza)Cl2], [Co(Etbdmpza)Cl2] are presented in Figure 1. The addition of even small amounts of water in the methanolic solution is followed by a precipitation of the initial ligand species [Co(bdmpza)] and methanol as a lattice solvent. Similar ‘wet’ ethanolic solution gave a polymeric [Co(bdmpza)2CoCl2]. On the other hand, the nitrate in the starting Co(NO3)2 is even followed by the precipitation of [Co(bdmpza)]·(NO3HNO3) with oxidized cobalt(III) species. The cobalt(II) chloride thus acts similarly as its copper analogue to participate in ester formation of the initial alcohol and bdmpza. The metal catalytic effect may well be related by the tetrahedral coordination spheres often found in a form of di-, tri-, and tetrachloride, or bromide species. In our case this would favour the suitable orientation of the bidentate ester coordination, instead of the tridentate anionic, the later found in the octahedral coordination species.

Poster Sessions MS.C3.P.440 Coordination Behavior of Praseodymium(III) Complex with Crown Ether and Picrate Eny Kusrini,*a Muhammad I. Saleh,b Rohana Adnan, b Bohari M. Yamin,c aDepartment of Chemical Engineering, Faculty of Engineering, Universitas Indonesia, 16424 Depok (Indonesia). b School of Chemical Sciences, Universiti Sains Malaysia, 11800 Penang (Malaysia). cSchool of Chemical Sciences and Food Technology, University Kebangsaan Malaysia,43600 Bangi, Selangor (Malaysia). E-mail: [email protected] The ternary complexation of praseodymium(III) with dicyclohexano-18-crown-6 (DC18C6) and picrate anion (Pic) were characterized by elemental analyses, FTIR (Fourier-transform infrared) spectroscopy, NMR, single crystal X-ray diffraction, and photoluminescence (PL). The [Pr(Pic)2(DC18C6)](Pic).0.5(DC18C6) complex is crystallized in triclinic with space group P-1. The complex had a ten-coordination number from the DC18C6 ligand in a hexadentate mode and the two Pic anions in bidentate modes, forming bicapped square-antiprismatic geometries. In the crystal, the DC18C6 molecule can act as the coordinated DC18C6 ligand in a hexadentate mode as well as the solvated molecule for its stabilizing the molecular structures. In the crystal , the molecular organization was further stabilized by the intra and intermolecular C-H...O hydrogen bonding. Three weak intramolecular hydrogen bonds, i.e. C3-H3B…O15, C5H5A...O8, and C15–H15A...O13 were observed. The rigid cyclic of DC18C6 ligand with cyclohexane rings have effected the coordination behavior and photoluminescence of complex. The Pr complex exhibits the corresponding characteristic photoluminescence in the visible and near infrared region. Coordination number and conformation structural from the lighter complexes are related to the selectivity factor in the separation of lanthanides due to the steric effect and the lanthanide contraction will be discussed in detail. Keywords: coordination, picrate complex, praseodymium

MS.C3.P.441 Kinetic Investigation Of Ethynyl Transmetalation From Tin(IV) To Gold(I) Carlo Levi, Luciano Canovese, Fabiano Visentin. Department of molecular Science and Nanosystems, “Cà Foscari” University, Venice. Email: [email protected] The reaction between [(NHC)AuCl] complexes (NHC = IMes, IPr, Me-Im-benzyl and R-Im-CH2Pyr) and tri-nbutyl(phenylethynyl)tin at 298 K in CDCl3 and CD3CN yields the phenylethynyl-gold(I) species [(NHC)AuCCPh]. The new complexes of the type [(R-Im-CH2Pyr) AuCCPh] (R= Me, Mes, DIPP) have been synthesized in CH2Cl2 and fully characterized. Kinetic measurement were carried out by UV-VIS technique in CHCl3. Under pseudo-first order conditions the transmetalation rates obey the law: kobs = k2*[Sn]. The k2 values increase with the decreasing of the NHC bulkiness and are unaffected by the presence of a CH2pyridine arm when the heteroditopic NHC ligand (Me-Im-CH2Pyr) are used as stabilizing ligand.

k2 (M-1s-1) [(Me-Im-Benzyl) AuCl] [(Me-Im-CH2Pyr) AuCl] [(Mes-Im-CH2Pyr) AuCl] [(DIPP-Im-CH2Pyr) AuCl]

NCNNHC [(NHC)AuCl] → [(NHC)AuCCPh]

0.53±0.01

171.5 → 187.6

0.50±0.01

171.6 → 187.7

0.25±0.01

172.3[a] → 188.5

0.14±0.01

173.4 → 189.5

[(IMes)AuCl]

0.074±0.003

173.4[b] → 189.0

[(IPr)AuCl]

0.0057±0.0003

175.1[b] → 190.9[c]

[a] M. Pažcký, A Loos, M.J. Ferriera, D. Serra, N. Vinokurov, F. Rominger, C. Jäkel, A.S.K. Hashmi, M. Limbach Organometallics 2010, 29, 4448-4458. [b] P. de Fremont, N.M Scott, E.D. Stevens, S.P. Nolan Organometallics 2005, 24, 2411-2418. [c] G.C. Fortman, A. Poater, J.W. Levell, S. Gaillard, A.M.Z. Slawin, I.D.W. Samuel, L. Cavallo, S.P.Nolan Dalton. Trans., 2010, 39, 1038210390.

Keywords: gold-ethynyl, tin-transmetalation, kinetics

MS.C3.P.442 Synthesis and Reactivity of Rhenium Cluster Complexes Containing Tetrazolate Ligands Lisa F. Szczepura,* Stanley A. Knott, Joan N. Tirado, Jessica L. Durham, Department of Chemistry, Illinois State University, Campus Box 4160, Normal, IL 61790-4160, USA. E-mail: [email protected] Previously, we reported that the [Re6Se8]2+ cluster core can activate acetonitrile to undergo cyclization with inorganic azides to form tetrazolate cluster complexes where both N1 and N2 isomers were characterized [1]. These represented the first examples of (tetrazolato)rhenium complexes. We have extended our initial report to investigate the activation of benzonitrile and para-substituted benzonitriles by the same cluster core. This presentation will discuss the synthesis of and characterization of a series benzonitrile and pheyltetrazolate cluster complexes (the structure of [Re6Se8(PEt3)5(2,5p-aminophenyltetrazolate)]+ is shown below). In addition, studies involving the protonation and alkylation of coordinated 5-substituted tetrazolates will be discussed.

[1] L. Szczepura, M. K. Oh, S. A. Knott, Chem. Commun. 2007, 4617-4619.

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Keywords: Hexanuclear rhenium clusters, small molecule activation, tetrazolate ligands

MS.C3.P.446

MS.C3.P.443

Structure and Properties of New Coordination Compounds of UO22+ with Schiff Bases Dan Maftei,a Ionel Humelnicua, Doina Humelnicua, Aurel Puia a “Alexandru Ioan Cuza” University Iasi, Romania. E-mail: dan. [email protected]

Co(III) Complexes of a Pyridyl-based Ligand: Hydrolysis and Facile C-H Exchange Warrick K. C. Lo,a James D. Crowleya and Allan G. Blackman.a a Department of Chemistry, University of Otago, Dunedin (New Zealand). E-mail: [email protected] A series of [CoIII(N4Py)X](ClO4)n (N4Py = (1,1-di(pyridin-2yl)-N,N-bis(pyridin-2-ylmethyl)methanamine),[1] X = Cl, OH, N3, NCS-κN, Br; n = 2: X = OH2, OSMe2-κO, NCMe; n = 3) complexes containing four pyridine donors and one tertiary amine donor has been synthesised. These complexes have been characterised through 1H, 13 C and two dimensional NMR studies, mass spectrometry and X-ray crystallography. Despite the lack of an NH proton, the reaction of [Co(N4Py)Cl]2+ to give [Co(N4Py)(OH)]2+, is base catalysed and probably proceeds via the pseudo-aminate mechanism proposed by Jackson et al.[2] for the hydrolysis of asym-[Co(dmpmetacn)Cl]2+ complex, which also lacks an NH proton. This involves C-H deprotonation, and support for this mechanism comes from the observation that the methylene protons of N4Py in some of the above [Co(N4Py)X]n+ complexes are significantly acidic, and exchange readily with deuterons in D2O under ambient conditions (Figure 1). 1 H NMR studies on [Co(N4Py)X](ClO4)n complexes show that, for some of these, two sets of methylene protons are chemically inequivalent in deuterated dimethyl sulfoxide but are chemically equivalent in D2O or deuterated acetone. Variable-temperature 1H NMR studies on [Co(N4Py)(OH2)]3+ reveal that a fluxional process, most likely chelate ring flipping (Figure 1), exists, and this makes all four CH2 protons chemically equivalent on the NMR timescale.

Figure 1. Deprotonation and deuteration at the methylene C of [CoIII(N4Py)X]n+ in D2O (top) and chelate ring flipping of [Co(N4Py)(OH2)]3+ (bottom). [1] M. Lubben, A. Meetsma, E. C. Wilkinson, B. Feringa, L. Que, Jr., Angew. Chem. Int. Ed. Engl., 1995, 34, 1512-1514. [2] A. J. Dickie, D. C. R. Hockless, A. C. Willis, J. A. McKeon, W. G. Jackson, Inorg. Chem., 2003, 42, 3822-3834.

In recent years, coordinative chemistry of uranium and thorium has been extensively developed, consequent with the interest manifested in the coordination compounds of transition metals and lanthanides. Synthesis and investigation of these coordinative compounds arise from the following reasons: a) study the coordinative chemistry aspects of actinides; b) investigation on the bonding interactions between the ligand and metal ion; c) identify convenient extractants for nuclear remediation. Coordinative compounds of transition metals with Schiff bases as complexing agents also represent promising materials for optoelectronic appliances, due their photo- and electro-luminiscent properties. Uranium (VI) as uranyl ion and thorium (IV) are known to form complexes with numerous Schiff bases, showing a strong affinity for ligands with oxygen- and nitrogen-bearing ligands. Thus, compounds formed between uranium and thorium with different complexing agents are of great interest in a wide range of possible applications, including metal ions extraction from ores, extraction of metal ions from low-concentrated solutions and removal of radioactive ions from contaminated wastewaters. Reported in this work are the synthesis and properties of two new coordination compounds of uranyl and thorium with selected Schiff bases as ligands. All coordination compound being investigated were characterized by elemental analysis, molar conductance and magnetic susceptibility measurements, thermal analysis, FTIR, UVVis and fluorescence studies. The structural pattern and the geometry of complexes as well as coordination number of the metal ions were assigned on the basis of physico-chemical parameters obtained from IR and UV-Vis spectra. The obtained compounds are stable in air, soluble in some polar organic solvents (DMF, acetonitrile and DMSO) and show fluorescent properties. A prototype structure of uranyl complexes has been investigated by means of computational chemistry. Theoretical investigations were carried out at the Density Functional Theory (DFT) level using the PBE0 parameter-free hybrid functional. A mixed approach was employed with respect to the basis set, namely 6-31+g(d) for oxygen and nitrogen, 6-31+G for carbon and hydrogen whereas uranium, due it’s nuclear charge, was described using the ECP78MWB largecore Stuttgart relativistic effective core potential and a corresponding ECP78MWB ANO basis set. All structures were fully optimized without symmetry constraints and final equilibrium geometries reported are confirmed by hessian eigenvalues calculations yielding no imaginary frequency. On the basis of obtained experimental results, combined with electronic structure calculations, possible structures for the compounds under study are proposed. Acknowledgements: The authors want to acknowledge here the financial support of CNCSIS-UEFISCSU, project number PNII-IDEI, no. 9/2010, code 239. [1] Th. Malutan, A. Pui, C. Malutan, L. Tatary, D. Humelnicu, J. Fluoresc., 2008, 18, 707. [2] D. J. Evas, P. C. Junk, M. K. Smith, Polyhedron, 2002, 21, 2421. [3] L. Tonghuan, D. Guojian, Z. Zhengzhi, J. Coord. Chem., 2009, 62, 2203.

Keywords: uranyl complexes, Schiff bases, DFT

Keywords: cobalt(III), N4Py, kinetics

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Poster Sessions

Poster Sessions MS.C3.P.447 Determination of LSER Coefficients for the Complexes of Dioxovanadium (V) with CDTA and MIDA Kavosh Majlesi, Saghar Rezaienejad, Niloufar Ghafari, Nazila Doustmand Sarabi. Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran. Iran. Email: kavoshmajlesi@ srbiau.ac.ir In spite of several reports in the literature about application of the linear free energy relationships (LFER) and specific ion interaction theories, there are no reports on the complexation of dioxovanadium(V) with trans-1,2-diaminocyclohexane-N, N, N΄, N´tetraacetic acid (CDTA) and methyliminodiacetic acid (MIDA) in different compositions of methanol by using the Kamlet-Abboud-Taft (KAT) equation [1-6]. Molecules can interact with their environment in the solution through a variety of molecular interactions. Solvation equations can be applied to physicochemical properties as LFER. Many of vanadium derivatives show pharmaceutical and biological effects. Insulin-like effects of vanadium has received considerable attention in recent years, suggesting promise for the treatment of diabetes mellitus type (II). Complex formation reaction of aminopolycarboxylic acids has extensively been studied for more than half a century in industry, medicine, inorganic, and analytical chemistry. Therefore in this study a UV spectrophotometric investigation for the complex formation reaction of dioxovanadium(V) with CDTA and MIDA was carried out in different compositions of methanol at I = 0.1 mol.dm-3 of sodium perchlorate and t = 25˚C. Dissociation constants have been calculated on the basis of potentiometric titrations. A general aim of the current research is to find out the linear solvation energy relationships (LSER) regression coefficients and to account quantitatively for the various interactions between a given solute molecule and its surroundings. The nonspecific solvent/solute interactions are approximately constant in the methanol aqueous solutions. Water structure can be enhanced due to the hydrogen bond rearrangements made by alcohol in methanolwater mixed solvents. Values of the LSER solvation parameters might be changed, because various alcohols enhance the water structure. The LSER parameters vary slightly in aqueous solutions of methanol and there is an increasing pattern for the variations of stability and dissociation constants. The two parameter (β, π*) equation can account for the variations and (α, β) model is in the second place. The variations for α, β and π* values and the signs of their coefficients are in consistent with the increasing trends which have been calculated for different compositions of methanol. [1] K. Majlesi, S. Rezaienejad, J. Solution. Chem. 40, DOI: 10.1007/s0953-0119754-7 (2012). [2] K. Majlesi, S. Rezaienejad, A. Rouhzad, J. Chem. Eng. Data 56, 541 (2011). [3] K. Majlesi, S. Rezaienejad, J. Chem. Eng. Data 56, 3194 (2011). [4] K. Majlesi, M. Gholamhosseinzadeh, S. Rezaienejad, J. Solution. Chem. 39, 665 (2010). [5] K. Majlesi, S. Rezaienejad, J. Chem. Eng. Data 55, 4491 (2010). [6] K. Majlesi, S. Rezaienejad, J. Chem. Eng. Data 55, 882 (2010)

Unusual properties have been observed for the bridging hydroxide ligand in a series of pyrazolate-based dinickel(II) and dipalladium(II) complexes, [LNi2(µ-OH)] and [LPd2(µ-OH):[1] (i) The 1H NMR signal of the µ-OH is detected at high field at around −6.7 (Ni) or −3.7 (Pd) ppm, typical for OH groups isolated by encapsulation.[2] Accordingly the IR bands for the µ-OH are sharp and found at high energy. (ii) Proton exchange of the µ-OH with an excess of D2O is extremely slow, with t½ around five weeks. The H/D exchange kinetics has been analyzed in detail. In addition, exchange of the complete OH group in isotopically labelled [LM2(µ-17OH)] has been followed by 17O NMR as well as 1H NMR spectroscopy. A mechanistic picture is derived from the kinetic and thermodynamic parameters, and is supported by DFT calculations.[1]

[1] D.-H. Manz, S. Katsiaouni, R. Mata, S. Demeshko, S. Dechert, F. Meyer, manuscript in preparation. [2] J. Geier, H. Grützmacher, Chem. Commun. 2003, 11, 2942-2943.

Keywords: Bimetallic Complexes, Bridging Ligands, H/DExchange Kinetics

MS.C3.P.449 Competitive Formation of 5- or 7-Membered cyclometallated Pt(II) Compounds Manuel Martínez, Margarita Crespo, Susanna Jansat, Departament de Química Inorgànica, Facultat de Química, Universitat de Barcelona, Barcelona (Spain). E-mail: [email protected] Oxidative addition of C-H bonds on organometallic Pt(II) compounds represent a key step in the reactivity involving important value added processes. We have been involved in kinetico-mechanistic studies of such reactions, and an important amount of information has been collected. [1,2] Recently, the formation of five- and seven-membered cyclometallated Pt(II) compounds -after reductive elimination of diphenyl units- has been observed, depending on the nature of the ligands involved.[3-5] The complete process can be summarized as indicated in the Scheme.

Keywords: LSER, CDTA, MIDA

MS.C3.P.448 Extremely Slow Proton Exchange of a Bridging Hydroxide in a Pyrazolate-Based Bimetallic Complex Dennis-H. Manz,a Stamatia Katsiaouni,a Ricardo Mata,b Serhiy Demeshko,a Sebastian Dechert,a Franc Meyer,a* aInstitute of Inorganic Chemistry, Georg-August-University, Tammannstrasse 4, D-37077 Göttingen, (Germany). aInstitute of Physical Chemistry, Georg-AugustUniversity, Tammannstrasse 6, D-37077 Göttingen, (Germany). E-mail: [email protected]

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Here we present the kinetico-mechanistic study of this set of reactions for different types of X and NCC cyclometallating ligands. The data has been collected at varying temperatures, pressures and solvents. A very fine tuning between the two possible reaction paths

Poster Sessions has been found in some cases; furthermore, the temperature effects result extremely relevant in some of the cases. A full picture of the activation effects determining the reactivity indicated in the Scheme is provided. [1] M. Crespo, M. Martínez, J. Sales, X. Solans, M. Font-Bardía, Organometallics, 1992, 11, 1288-1295. [2] M. Crespo, M. Martínez, E. de Pablo, J. Chem. Soc., Dalton Trans., 1997, 1231-1235. [3] T. Calvet, M. Crespo, M. Font-Bardía, K. Gómez, G. González, M. Martínez, Organometallics, 2009, 28, 5096-5106. [4] M. Crespo, M. Font-Bardia, T. Calvet, Dalton Trans., 2011, 40, 9431-9438. [5] R. Martín, M. Crespo, M. Font-Bardia, T. Calvet, Organometallics, 2009, 28, 587-597.

Keywords: Cycloplatination, kinetics, mechanisms

MS.C3.P.450 Novel Methane-tricarboxamides: Synthesis, Structure and Metal Binding Juliane März,a Maria Abraham,b Axel Heine,a Kerstin Gloe,a Karsten Gloe,a aTU Dresden, Department of Chemistry and Food Chemistry, Dresden (Germany); bRWTH Aachen, Institute of Inorganic Chemistry, Aachen (Germany). E-mail: [email protected] The defined self-assembly of small molecules possessing selfcomplementary amide functions has been studied intensely over the last years. From this point of view benzene-1,3,5-tricarboxamides are interesting systems which allow the self-assembly of helical, chainlike or porous supramolecular polymers [1-3]. Such ligands also form metal-organic frameworks with different d- and f-block metal ions [4].

Fig. 1 left: formulas of ligands 1a (2-Py), 1b (3-Py) and 1c (4-Py); right: triple-helical arrangement of 1a

P. Lightfoot, F. S. Mair, R. G. Pritchard, J. E. Warren, Chem. Commun., 1999, 1945–1946. [4] J. Wu, P. Wang, C. Huang a, L. Fu, C. Song, H. Hou, J. Chang, Inorg. Chem. Commun., 2012, 15, 301–304.

Keywords: amide, metallogel, triple-helix

MS.C3.P.451 Self-Assembly of Polynuclear Methylenediphenol Clusters: ESIMS and X-Ray Study Vickie McKee, Imdad Hussain, Rafal Kulmaczewski, Chemistry Department, Loughborough University, Loughborough, (UK). E-mail: [email protected] Condensation of methylenediphenol dialdehydes with diamines using transition metal template ions yields di-, tri- and tetranuclear complexes of {2+2} macrocycles [1], [2]. Addition of a group 1 or group 2 metal ion as a second template ion results in a range of larger, mixed metal assemblies, including sandwich structures incorporating the {2+2} macrocycle as well as {3+3}, {4+4}, and higher analogs. Modifications of the reaction conditions can be used to direct these reactions towards single products. A combination of ESI-mass spectrometry of reaction solutions and X-ray crystallographic characterisation of the products was used to investigate the mechanisms of the self-assembly processes [3]. We have shown that formation of the [BaCu4{4+4}]2+ macrocyclic ion is a double template process for which the Ba2+ and Cu2+ ions are both essential. The function of the Ba2+ ion is to bind four methylenediphenolate units, while the purpose of the Cu2+ ions is to orient the aldehyde groups suitably for a diamine to complete the Schiff-base cyclisation. Further, formation of the macrocycle goes via a [BaCu4(diphenolate)4]2+ metallacyclic intermediate which forms cleanly and rapidly in the presence of the metal ions, the methylenediphenol and base. Subsequent Schiff-base condensation with diamine to form the macrocycle is a stepwise process in which reaction of the first two diamines is fast but than the third and fourth groups condense much more slowly (Scheme). Other metal template ion combinations and other methylenediphenol units offer clean routes to an extended range of new assemblies [4].

Fig. 2 left: supramolecular Cu(II) gel of 1b, right: SEM image of the xerogel [1] A. R. A. Palmans, J. A. J. M. Vekemans, H. Kooijman, A. L. Spek, E. W. Meijer, Chem. Commun., 1997, 2247-2248. [2] Y. Nakano, T. Hirose, P.J. M. Stals, E. W. Meijer, A. R. A. Palmans, Chem. Sci., 2012, 3, 148-155. [3] M.

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Now, we report the synthesis of the novel 2-, 3- or 4-picolyl substituted methane-tricarboxamides 1a-c and relevant metal complexes. The moleculare structure of N,N‘,N‘‘-Tris(2-picolyl) methane-tricarboxamide 1a is characterized by a triple helical arrangement (Fig. 1) based on strong N‑H…O hydrogen bonds between different molecules. Furthermore, weak C-H…O, N-H…O and C-H…π interactions are stabilizing the structure. This chiral structure is formed upon crystallization from achiral components. Complexation studies using UV-Vis and NMR spectroscopy as well as potentiometric measurements show strong interactions of 1a-c with Co(II), Ni(II), Cu(II) and Ag(I). These metal ions also give stable supramolecular metallogels with 1b and 1c in methanol or water/ ethanol resp. (Fig. 2).

[1] J. Barreira Fontecha, S. Goetz, and V. McKee. Angew. Chemie, Int. Ed., 2002, 41, 4554-4556. [2] J. Barreira Fontecha, S. Goetz and V. McKee, Dalton Trans., 2005, 923-929. [3] J. Barreira-Fontecha, R. Kulmaczewski, X. Ma and V. McKee. Dalton Trans., 2011, 40, 12040-12043. [4] R. Kulmaczewski, I. Hussain and V. McKee, unpublished work.

Keywords: self-assembly, template, macrocycle

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Poster Sessions MS.C3.P.452

MS.C3.P.453

Redox Properties of Ru (II/III) Complexes with 1,4,5,6-tetrahydropyrimidyl-2-phenolate Ryoji Mitsuhashi, Takayoshi Suzuki, Yukinari Sunatsuki, Graduate School of Natural Science and Technology, Okayama University, Okayama (Japan). E-mail: [email protected]

A Novel Fluoride-Bridged Ni(II) Trimeric Complex Having N-Alkylethylenediamine Keiko Miyamoto,a Yuki Ishikawa,a Ernst Horn,a Yumi Ida,b Takayuki Ishida,b aCollege of Science, Rikkyo University (Japan). bDepartment of Engineering Science, The University of Electro-Communications (Japan). E-mail: [email protected]

Coordinating ligands with π-conjugating N–H or O–H moieties are potential candidates for a proton-coupled electron transfer (PCET) reaction that is a fundamental reaction in nature. Many ruthenium complexes with bidentate imidazolyl or imidazolinyl ligands were synthesized and characterized to investigate this phenomenon. Such ligands often contain 2-pyridyl group to form a 5-membered chelate ring. We are interested in 1,4,5,6-tetrahydropyrimidyl-2-phenol (H2Lthp: Fig. 1a) which acts as a bidentate ligand in the mono-deprotonated form with π-conjugating N–H moiety. This ligand is supposed to have a conjugation between phenolate and tetrahydropyrimidyl group due to the presence of phenoxide group, whereas the conjugation in the pyridyl analogue is not so strong. This conjugation affects the redox properties of the complexes. However, the PCET reactions with such phenol-based ligands have not been studied well so far. In order to investigate the conjugation effect of phenolate moiety on redox property, we focused on ruthenium complexes with (HLthp)– and (HLimi)– (H2Limi = 2-imidazolinyl-2-phenol: Fig. 1b). A stoichiometric reaction of [RuCl2(bpy)2] (bpy = 2,2’-bipyridine) and respective monodeprotonated ligands afforded dark purple solution and [RuII(HLthp)(bpy)]+ (Fig. 1c) and [RuII(HLimi)(bpy)]+ were isolated as tetrafluoroboate salt. When these Ru(II) complexes were treated with Ag+, the corresponding Ru(III) complexes were readily obtained and isolated. All the Ru(II) and Ru(III) complexes were characterized by X-ray analysis and they are air-stable both in the solid state and in solution. When an excess amount of NaOH was added to an aqueous solutions of the Ru(III) complexes, the Ru(III) center was reduced to Ru(II) state without change in the coordination structure. In general, deprotonation from the π-conjugating N–H moiety induces oxidation of the metal center. Although there are some reports on the reduction of Ru(III) ion triggered by deprotonation from the ligand, they are accompanied by oxidation of the ligand [1]. In our complexes, the coordination environment was unchanged. Thus, we observed an unusual proton-coupled redox reactions based on the ligand with phenolate substituent.

One of our research focuses has been the chromotropic behaviour of mixed ligand complexes of transition metals.[1] Chloride-bridged Ni(II) trimeric complex having N,N,N’,N’tetramethylethylenediamine (=tmen), [Ni3(tmen)3Cl4(OH)]Cl, was first crystalized by a Finnish chemist[2] and later the bromide analogue was reported[3]. Our attempts to synthesize the iodide analogue was not successful[4]. Finally, we have obtained the fluoride analogue. The structural analysis shows that all three trimeric complexes are isostructural. However, the fluoride-bridged trimeric complex shows very different properties from other two, for example, the fluoride crystals are very soluble and dissolves quickly when it is exposed to water, while the chloride- and bromide-bridged trimeric complex are sparingly soluble in water. The fluoride crystals show neither solvatochromism nor thermochromism, while the chloride-bridged complex changes its color from green to pink, and the bromide-bridged complex from green to purple when heated. Both of them also show solvatochromism. We are also interested in mixed halide trimeric complexes where the µ2 and µ3 halides are different, and so far obtained (Br, Cl) trimer where µ2-Cl and µ3-Br are mixed[5] (see Fig.1 below) and (Cl, F) trimer where µ2-F and µ3-Cl are mixed. The chloride-bridged trimeric complex [Ni3(tmen)3Cl4(OH)]Cl shows a ferromagnetic interaction. 2J/kB = 15.1(2) K.

Fig.1 An ORTEP (30% probability ellipsoids) plot of the (Br, Cl) trimer. Hydrogen atoms and methyl carbons of tmen are omitted for clarity.

Fig. 1. a) ligand H2Lthp, b) ligand H2Limi, c) ORTEP of [Ru(HLthp)(bpy)2]+ (hydrogen atoms are omitted for clarity except for N–H atom). [1] T. Koizumi, T. Kambara, Bull. Jpn. Soc. Coord. Chem., 2010, 56, 14-23.

Keywords: Redox properties, Ru(II/III) complex, Phenolate-based ligand

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[1] K.Miyamoto, M.Sakamoto, C.Tanaka, E.Horn, Y.Fukuda, Bull. Chem. Soc. Jpn., 2005, 78, 1061-1071. [2] U.Turpeinen, A.Pajunen, Finn. Chem. Lett., 1976, 6-11. [3] D.A.Handley, P.B.Hitchcock, G.J.Leigh, Inorg.Chim.Acta., 2001, 314, 1-13. [4] K.Miyamoto, R.Koizumi, E.Horn, Y.Fukuda, Z.Kristallogr. NCS., 2006, 221, 123-125. K.Miyamoto, E.Horn, Y.Fukuda, Z.Kristallogr. NCS., 2006, 221, 126-128. [5] E.Horn, K.Miyamoto, Y.Fukuda, Z.Kristallogr. NCS., 2007, 222, 184-186.

Keywords: nickel(II), fluoride-bridged, chromotropism

Poster Sessions

Metal Complexes Containing Optically Active Schiff Bases and Their Cytotoxicity against Breast Cancer Cell Lines Mohamed Ibrahim Mohamed Tahir,a Sang-Loon Tan,a Karen A. Crouse,a Rozita Rosli,b David J. Watkin,c aDepartment of Chemistry, Universiti Putra Malaysia, Serdang (Malaysia). bDepartment of Obstetrics and Gynaecology, Universiti Putra Malaysia, Serdang (Malaysia). cDepartment of Chemistry, University of Oxford, Oxford (United Kingdom). E-mail: [email protected] Dithiocarbazic acid and its substituted analogs is an important class of compound that offer versatile applicabilities and tunable physico-chemical properties in chemical research [1-3]. As a concerted effort to gain more insight into the structure-activity relationship, two Schiff bases were obtained through acid catalysed condensation between S-methyldithiocarbazate and enantiomerically pure camphor and camphorquinone. Subsequent complexation of the NS and NOS chelating ligands with Zn(II) and Cd(II) afforded a series of isomeric structures with inherited chiroptical properties as indicated from circular dichroism spectroscopy. X-ray crystallographic analysis shows that the chiral ligands adopted either Δ or Λ helicity around the metal centre and thus enable the correlation of absolute structure with optical activity. The metal complexes were subjected to in vitro cytotoxic screening against two types of breast cancer cell lines, namely the breast cancer cells of estrogen receptor positive (MCF-7) and breast cancer cells of estrogen receptor negative (MDA-MB-231). In addition, the compounds were tested against normal breast epithelial cells (MCF10A) as a control measure to compare their toxicity towards the normal and cancerous cell lines. The result shows that Cd complexes are highly active against the cancer cells, despite there are no systematic reactivity pattern observed in all the enantiomeric metal complexes. [1] M.A.F.A. Manan, M.I.M. Tahir, K.A. Crouse, F.N.F. How, D.J. Watkin J. Chem. Crystallogr., 2012, 42, 173-179. [2] H.P. Zhou, D.M. Li, P. Wang, L.H. Cheng, Y.H. Gao, Y.M. Zhu, J.Y. Wu, Y.P. Tian, X.T. Tao, M.H. Jiang, H.K. Fun J. Mol. Struct., 2007, 826, 205-210. [3] M.X. Li, L.Z. Zhang, C.L. Chen, J.Y. Niu, B.S. Ji J. Inorg. Biochem., 2012, 117-125.

Keywords: chiral Schiff bases, Zn(II) and Cd(II) complexes, breast cancer

MS.C3.P.455 Molybdenum (VI) and (IV) Bis(Dithiolate) Complexes as Models of Molybdoenzymes Zeinab Moradi-Shoeili, Davar M. Boghaei, Department of Chemistry, Sharif University of Technology, Tehran (Iran). E-mail: dboghaei@ sharif.edu Molybdenum enzymes are found in nearly all organisms, and have been shown to be involved in a wide variety of enzyme catalytic cycles of the carbon, nitrogen and sulfur metabolisms. Many studies have been conducted to determine the ability of cis-[MoO2]2+ core complexes that mimic oxo-transferases and/or specific features of its active sites. Most of the well-characterized model compounds of molybdoenzymes have been found to have one or two metal-binding pterin-substituted 1,2-enedithiolate ligands bound to the molybdenum in the active site. As a part of our investigations on new model complexes for molybdenum-containing oxo-transferases, we report here the Mo(VI)-dioxo and Mo(IV)-oxo complexes of the Pyrido[2,3-b] pyrazine-2,3-dithiol (H2ppdt) ligand in order to study the ligand´s topology on the catalyst activity in oxygen atom transfer. The

[Bu4N]2[MoVIO2(ppdt)2] (1) compound was prepared in high yield by reaction of MoO2Cl2 with H2ppdt in methanol. The air-sensitive [Bu4N]2[MoIVO(ppdt)2] (2) complex has been successfully derived from the corresponding Mo(VI)-dioxo complex by oxo abstraction with PPh3. The complexes characterized by elemental analysis, IR, UV/Vis, and 1H NMR spectroscopies. The kinetics of the oxotransfer reaction between (1) and PPh3 was studied spectrophotometrically in DMF medium that proceeded in second order as v=−d/dt[MoO2]= k[MoO2][PPh3]. In the reverse oxo transfer reaction of (2) with biological and nonbiological oxygen donors such as DMSO and Me3NO, corresponding dioxomolybdenum(VI) complex and Me3N were formed quantitatively. This indicates the clean conversion during the reduction and the absence of (µ-oxo)dimolybdenum(V) complex formation in the present reactions controlled by the unique electronic properties and the strength of chelation of the dithiolato ligands. [1] J. H. Enemark, J. J. A. Cooney, J. J. Wang, R. H. Holm, Chem. Rev., 2004, 104, 1175–1200. [2] J. J. Wang, R. H. Holm, Inorg. Chem., 2007, 46, 1115611164. [3] H. Sugimoto, H. Tano, H. Miyake, S. Itoh, Dalton Trans., 2011, 40, 2358. [4] A L. Tenderholt, K. O. Hodgson, B. Hedman, R. H. Holm, E. I. Solomon, Inorg. Chem. 2012, 51, 3436−3442.

Keyword: molybdoenzymes, oxo-transferase, dithiolato ligands

MS.C3.P.456 Preparation, Structures and Properties of Ru(II) Complexes with Hydrazone Ligand Asami Mori,a Takayoshi Suzuki,a Yukinari Sunatsuki,a Kiyohiko Nakajima,b Atsushi Kobayashi,c Ho-chol Chang,c Masako Kato,c a Graduate School of Natural Science and Technology, Okayama University, Okayama (Japan). bAichi University of Education, Kariya (Japan). cDivision of Chemistry, Hokkaido University, Sapporo (Japan). E-mail: [email protected] Bistable switching, that is reversible conversion of molecular structures and/or properties by external stimuli, has been attracted much attention in current transition-metal chemistry. As one of possible candidates for the reversible switches, we are interested in the coordination compounds of hydrazone derivatives having associated donor groups (e.g., HL1 in Figure 1), because they have many kinds of coordination modes, in addition to deprotonation from the N–H moiety and configurational isomerism (E and Z forms) of the azaethene moiety. In this study, we have prepared new ruthenium(II) complexes with HL1, [RuCl2(PPh3)2(HL1)] (1–4: Figure 2), and characterized their molecular structures and spectro-scopic as well as electrochemical properties.

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MS.C3.P.454

Figure 1. Structure of HL1

Reaction of HL1 with [RuCl2(PPh3)3] under various reaction conditions (e.g., solvent and/or temperature) gave four isomers of [RuCl2(PPh3)2(HL1)] (1–4), which were isolated selectively from the respective reaction mixture: 1, in CH2Cl2 at 0 °C; 2, in EtOH at r.t.; 3, in EtOH at 80 °C; and 4, in ClCH2CH2Cl at 80 °C. The crystal and

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Poster Sessions molecular structures of 1–4 were determined by X-ray analysis. In complexes 1–3, the ligand HL1 in the Z form coordinates through the imine-N and amide-O atoms, while in complex 4 HL1 in the E form binds to RuII via the quinoline-N and imine-N atoms. Complexes 1–3 are the geometrical isomers with respect to the PPh3 and Cl– coordination. Complex 1 with a trans(Cl),cis(P) configuration was converted to 2 (cis,cis-isomer) in CH2Cl2 at room temperature, and 2 also thermally converted to 3 with a cis(Cl),trans(P) configuration under refluxing in EtOH. Thus, the thermodynamic stabilities of 1, 2, and 3 became higher in this order, and 1 would be a kinetically preferable product from a reaction of HL1 with [RuCl2(PPh3)3]. The bulkiness of PPh3 would give a key factor for these structural conversions. In CH2Cl2, all complexes exhibit a reversible RuII/III redox couple in the potential range of 0.41–0.11 V (vs. Ag/Ag+). The redox potential was shifted in the order of 4 > 2 ≈ 1 > 3, which was also supported by the DFT calculations. The p-back bonding of PPh3 and the coordination mode of HL1 would affect the energy levels of HOMOs in these complexes. The spectroscopic characterization of 1–4 and the attempts to prepare heterodinuclear complexes using (L1)– as a bridging ligand will also be reported.

Fig. 1: The molecular structure of [{CpFe(CO)2}(μ-HMTA)](BF4)2 showing atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level with H atoms presented as small spheres. [1] C.M. M’thiruaine, H.B. Friedrich, E.O. Changamu, M.D. Bala, Inorg. Chim. Acta, 2011 366, 105-115. [2] C.M. M’thiruaine, H.B. Friedrich, E.O. Changamu, M.D. Bala, Inorg. Chim. Acta, 2012, 382, 27-34.

Keywords: N-heterocyclic, iron dicarbonyl complexes

MS.C3.P.458

Figure 2. Structures of 1–4

Keywords: conversion

hydrazones,

ruthenium(II)

complexes,

thermal

MS.C3.P.457 Reactions of N-heterocyclics with [Cp(CO)2Fe(OEt2)]BF4 and [Cp*(CO)2Fe(THF)]BF4 Cyprian M. M’thiruainea, Holger B. Friedricha, Evans O. Changamub, Muhammad D. Balaa. aSchool of Chemistry, University of KwaZuluNatal, Durban (South Africa). bChemistry Department, Kenyatta University, Nairobi (Kenya). E-mail: [email protected] Most organometallics containing the half sandwich moiety [(η5C5R5)(CO)2Fe] (R = H; R = CH3) are neither soluble nor stable in water. We have been investigating the possibility of synthesizing watersoluble organometallics of this moiety by reacting the substitutionally labile compounds [Cp(CO)2Fe(OEt2)]BF4 (Cp = η5-C5H5) and [Cp*(CO)2Fe(THF)]BF4 (Cp* = η5-C5(CH3)5) with different amine ligands [1, 2]. Herein we report the reactions of the ether compounds [Cp(CO)2Fe(OEt2)]BF4 (Cp = η5-C5H5) and [Cp*(CO)2Fe(THF)] BF4 (Cp* = η5-C5(CH3)5) with N-heterocyclic ligands including 1,3,5,7-tetraazaadamantane (HMTA), 1,4-diazabicyclo[2.2.2]octane (DABCO), and 1-methylimidazole (1-meIm). The majority of the isolated compounds exhibited high solubility and stability in water. The results, including the structures of some of the isolated compounds as determined by single crystal crystallography, will be discussed in detail. Fig. 1 is an example of the structures that will be discussed.

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Chemistry of 5-Substituted 3-(Pyridine-2-yl)pyrazolates with s-Block Metals Christoph Müllera Björn Schowtkaa, Tobias Klouberta, Matthias Westerhausen,* Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, Humboldtstraße 8, D-07743 Jena, (Germany). E-mail: [email protected], Bjoern. [email protected], [email protected], [email protected] Pyrazole-based systems gained tremendous importance in main group and transition metal chemistry [1]. Besides widespread use as scorpionate ligands in tris(pyrazolyl)borates [2], the substitution in 3,5 position is a valuable possibility to influence steric and electronic properties. Whereas well-known 3,5-bis(pyridine-2-yl)pirazolato ligands often lead to polymeric and poorly soluble complexes, variation of this multidentate azaligand allows the preparation of soluble derivates. Deprotonation of the well-known 3,5-(bispyridin-2-yl)-pyrazole yields monoanionic chelating ligands which represent valuable ligands in main group coordination chemistry. Metalation of 3-(R’)-5-(pyridine-2-yl)pyrazole (HPz) with alkyllithium or dialkylzinc in tetrahydrofuran (thf) lead to the formation of homoleptic dinuclear complexes [(thf)Li(Pz)]2 and [(Et)Zn(Pz)]2 (R‘=2-pyridyl, 2- thiophenyl or phenyl) (Fig. 1). The metal-metal distance plays a significant role on the reactivity in stoichiometric and catalytic reactions. The reaction of alkaline earth metal bis(amides) Ae{N(SiMe3)2}2 yields in case of magnesium mononuclear [Mg(thf)2(Pz)2] with an octa-coordinate metal center. In case of calcium, dinuclear [{(thf)2Ca} (µ-Pz)3Ca(Pz)] with alkaline earth metals in two different coordination spheres are observed.

Poster Sessions

Fig. 1: [(thf)Li(Pz)]2

[Mg(thf)2(Pz)2]

[1] S. Trofimenko, Chem. Rev. 1993, 93, 943-980. [2] C. Pettinari, R. Pettinari, Coord. Chem. Rev. 2005, 249, 525-543. [3] T.Kloubert, H. Görls, M. Westerhausen, Z. Anorg. Allg. Chem. 2010, 636, 2405-2408. [4] T.Kloubert, H. Görls, M. Westerhausen, Z. Naturforsch., 2012,67b, in press.

MS.C3.P.460 Formation of Imine, Ammine, and Amine from Azide Ion on Ruthenium Complex Hirotaka Nagao, Sohei Fukui, Ryo Uehara, Department of Materials and Life Sciences, Sophia University, Tokyo (Japan). E-mail: h-nagao@ sophia.ac.jp Conversion reactions of nitrogen-containing compounds are important processes and have been investigated using variety of metal complexes. The reaction of the coordinated azide ion to the ruthenium(II) center with methyl iodide in acetonitrile has been reported to afford the novel methyleneimineruthenium(II) complex [1]. The azido ligand is a useful nitrogen source for syntheses of nitrogen-containing compounds. In this study, reactions of the azidoruthenium(II) complex, cis-[RuII(N3)2(bpy)2] (bpy = 2,2’-bipyridine), with haloalkane (RCH2X: R = H, Me, Et; X = I, Br) were investigated under various reaction conditions as summarized in Scheme 1. Reactions of cis-[RuII(N3)2(bpy)2] with haloalkane in CH3CN afforded corresponding acetonitrile-imineruthenium(II) complexes, cis-[RuII(NCCH3)(NH=CHR)(bpy)2]2+. The bis(imine) complex, cis-[RuII(NH=CHCH3)2(bpy)2]2+, was formed by the reaction with CH3CH2I in (CH3)2CO. Formation of imine complexes occurred without electron and proton sources. In the presence of CH3OH as an electron source, the azido ligand was converted into an ammine (NH3) and monoalkylamine (NH2R). A monoazido-imine complex was formed by the reaction in CH2Cl2 and changed into bis(imine) complexes by further reaction with haloalkane under similar conditions. These results indicated that the azido ligands on ruthenium complex reacted with haloalkane stepwise via the monoazido complex. The imine complexes (RuIINH=CHR)2+ were oxidized to corresponding nitrile complexes (RuIINCR)2+ by electrochemical and chemical reactions. Imine, amine, ammine, and nitrile ligands were substituted by azide ions in the reaction with NaN3 at room temperature to give the monoazido complex, and the diazido complex under heating conditions.

Scheme 1. Reaction of [RuII(N3)2(bpy)2] with haloalkane. [1] H. Nagao, T. Kikuchi, M. Inukai, A. Ueda, T. Oi, N. Suzuki, and M. Yamasaki, Angew. Chem. Int. Ed., 2006, 45, 3131.

Keywords: ruthenium, azide ion, haloalkane

MS.C3.P.461 S-Alkylation of Benzenethiol with Various Reagents over Halide Cluster Catalysts Sayoko Nagashima,a Kentaro Kudo,a Hitomi Yamazaki,a Satoshi Kamiguchi,b Teiji Chihara,a aGraduate School of Science and Engineering, Saitama University, Saitama (Japan). bRIKEN, Wako (Japan). E-mail: [email protected] Various types of halide cluster complexes have been synthesized by combining 19 types of Group 3–7, lanthanide, and actinide transition metals with four types of halogen atoms as ligand. These halide clusters have several characteristic features: metal–metal bonds that are similar to those in bulk metals, multicenter and multielectron systems, intermediate oxidation states of the metal atoms between 1+ and 3+, a diversity of metal atoms and halogen ligands, and low vapor pressure and high melting point for the metal halogenated complexes. Taking these features into consideration, we have been studying the application of halide cluster complexes as catalysts and found various reactions, e. g., synthesis of 3-methylbenzofuran from phenol and acetone [1] and synthesis of indenes from benzaldehyde and ketones. In this work, benzenethiol was reacted with methanol under a hydrogen stream in the presence of [(Nb6Cl12)Cl2(H2O)4]·6H2O supported on silica gel. When the temperature was raised above 250 °C, the catalytic activity of the cluster occurred, yielding methyl phenyl sulfide. The selectivity was 98% at 400 °C. Side reactions were the coupling of benzenethiol yielding diphenyl sulfide and diphenyl disulfide with 0.2% and 1.8% selectivity, respectively. The turnover frequency per cluster during a period of 2–4 h was 95.6 h–1, assuming that all of the cluster molecules were active. Molybdenum, tantalum, and tungsten halide clusters with the same octahedral metal framework also catalyzed the reaction. Primary C2-C5 alcohols were also effective reagents for the S-alkylation. Aliphatic ethers, dialkyl carbonates, and orthoesters were effective reagents for the S-alkylation at 400 °C. Alkyl halides also afforded the corresponding alkyl phenyl sulfides at 300 °C. When 1-hexene was applied to the reaction, spontaneous and catalytic S-alkylation proceeded simultaneously above 200 °C, yielding n-hexyl phenyl sulfide. When alkyl acetates were subjected to this reaction, the niobium cluster afforded S-phenyl thioacetate, whereas the other

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Keywords: pyrazoles, dinuclear complexes, s-block metals

Poster Sessions clusters afforded alkyl phenyl sulfides selectively. A Brønsted acid site, as Eqs. (1)–(3) show, attributable to a hydroxo ligand, which is formed on the cluster complex by thermal activation, is proposed as the active site of the catalyses. [(Nb6Cl12)Cl2(H2O)4]·4H2O → [(Nb6Cl12)Cl2(H2O)4] + 4H2O (1) [(Nb6Cl12)Cl2(H2O)4] → [(Nb6Cl12)Cl(OH)(H2O)3] + HCl (2) [(Nb6Cl12)Cl(OH)(H2O)3] → H+ + [(Nb6Cl12)Cl(O)(H2O)3]− (3)

Fig. 1. Hydrazone ligands used in this work

Keywords: structure conversion, hydrazone, Pd(II) complex

MS.C3.P.463 [1] S. Nagashima, S. Kamiguchi, S. Ohguchi, T. Chihara, Catalysis Today, 2011, 16, 135-138.

Keywords: halide cluster, S-alkylation, benzenethiol

MS.C3.P.462 Photo and Thermal Structure Conversion of Hydrazone-Pd(II) Complexes in the Solid and in Solution Kiyohiko Nakajima,a Fumi Kitamura,a Asami Mori,a Atsushi Kobayashi,b Ho-chol Chang,b Masako Kato,b aDepartment of Chemistry, Aichi University of Education, Kariya, Aichi 448-8542 (Japan). bDivision of Chemistry, Graduate School of Science, Hokkaido University, Sapporo 060-0810 (Japan). E-mail: knakajim@ auecc.aichi-edu.ac.jp Hydrazones are extensively used for the identification of carbonylic compounds, and also used as plasticizing agents and polymerization initiators. On the other hand, a certain type of hydrazones can act as a ligand to form metal complexes, which are of interest in the field of homogeneous catalysis and bioinorganic chemistry. Accordingly, much interest has been paied to the metal complexes containing such functional hydrazone ligands. We successfully prepared several Pd(II) complexes containing tridentate hydrazone ligands (Fig. 1). The complexes exhibited distinct color changes by additions of acids or bases. Thermal structure conversion of the Pd(II) complexes were observed in acidic conditions, however, the reaction proceeded photochemically in basic conditions. The photo and thermal structure conversion mechanisms of hydrazone-Pd(II) complexes were elucidated. We also report on the reversible structure conversion of the complexes in the solid.

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Zn(II) and Cd(II) complexes with 4-methoxysalicylaldehydebenzoylhydrazone Boriana Nikolova-Mladenova,a Darvin Ivanov,a aDepartment of Chemistry, Faculty of Pharmacy, Medical University of Sofia, Sofia (Bulgaria). E-mail: [email protected] Hydrazones derived from salicylaldehyde are compounds with interesting biological properties including a high anticancer activity. Salicylaldehydebenzoylhydrazone (SBH) is an unusually potent inhibitor of DNA synthesis and cell growth in a variety of cultured human and rodent cells. Various derivatives of salicylaldehyde benzoylhydrazone and their metal complexes have been synthesized in order to discover new more effective antiproliferative agents. Affinity towards Zn(II) is of interest since the metabolism of this ion is known to be greatly perturbed during treatment of iron overload. In the present study we report the synthesis and physicochemical characterization of Zn(II) and Cd(II) complexes of a new Schiff base – 4-methoxysalicylaldehydebenzoylhydrazone. The complexes were prepared by adding an aqueous solution of zinc or cadmium salts to an ethanolic solution of hydrazone in amounts equal to metal : ligand molar ratio of 1 : 2. The new ligand and the complexes were characterized by different physicochemical methods - elemental analyses, IR, 1H-NMR and 13C-NMR spectroscopy. The complexes are found to have formulae [ML2], where M = Zn(II) and Cd(II) and L is deprotonated ligand. The coordination behavior of 4-methoxysalicylaldehydebenzoylhydrazone towards Zn(II) and Cd(II) is investigated at theoretical and experimental level. The metal-ligand binding mode is predicted through molecular modeling to be realized through the oxygen of the deprotonated OH group, the oxygen of the keto C=O group and the azomethine nitrogen. The suggested binding mode is confirmed by comparative analysis of the spectral data of the free ligand and complexes. B3LYP/6-31+G (d, p) optimized geometry of the Cd-complex is shown further down:

Poster Sessions MS.C3.P.465 Photo-Induced Hydrogenation Reactions Utilizing Ruthenium NAD Model Complexes Hideki Ohtsu,a,b Koji Tanaka,a,b aInstitute for Molecular Science, Okazaki, (Japan). bInstitute for Integrated Cell-Materials Sciences (iCeMS), Kyoto University, Kyoto (Japan). E-mail: hohtsu@icems. kyoto-u.ac.jp

Keywords: 4-methoxysalicylaldehydebenzoylhydrazone-1, complexes-2, calculations-3

MS.C3.P.464 Synthesis, Characterization and Crystal Structure of Copper(II) Complexes Containing Carboxamide Ligands Mehri Noroozi Tisseh,a Maryam Kargarrazi,a Hamid Reza Khavasi,b a Department of Chemistry, Islamic Azad University, North Tehran Branch, Tehran, (Iran). bDepartment of Chemistry, Shahid Beheshti University, General Campus, Evin, Tehran 1983963113 (Iran). E-mail: [email protected] Contemporary inorganic crystal engineering involves design and synthesis of inorganic crystals [1]. Crystal engineering aims at understanding intermolecular interactions and exploring these analytical results at the synthesis of new structures with variety of properties, functions and applications. Prediction of crystal structure’s details and their consistent is still difficult, as the little change in tecton may eliminate or produce some expected synthons, and certainly transformation in packing, orientation of molecular building blocks and definitely most of the crystallographic parameters will be seen [2]. Nowadays, crystal engineering has become one of the alluring fields of chemical research and the evaluation of intermolecular interaction and their effects in the packing is the most interesting part of crystal engineering. In this regard, N-(aryl)-2-pyrazinecarboxamide ligands with different aryl groups (below scheme) have been employed for the synthesis of Cu(II) complexes in order to get insights to the substituent effects on the molecular architecture of complexes. Our results show the steric properties of the aryl group significantly alter the molecular architecture and coordination sphere of complexes.

Figure 1. Crystal structures of (a) [Ru(bpy)2(3Me1-pbn)]2+ and (b) [Ru(bpy)2(3Me1-pbnHH)]2+ and views of the twisted (c) 3Me1-pbn and (d) 3Me1-pbnHH ligands. [1] (a) T. Koizumi, K. Tanaka, Angew. Chem. Int. Ed. 2005, 44, 5891-5894; (b) E. Fujita, K. Tanaka et al., Angew. Chem. Int. Ed. 2007, 46, 4169-4172; (c) T. Fukushima, T. Wada, H. Ohtsu, K. Tanaka, Dalton Trans. 2010, 39, 11526– 11534. [2] H. Ohtsu, K. Tanaka, Chem. Commun. 2012, 48, 1796–1798. [1] C. B. Aakeröy, N. R. Champness, C. Janiak, CrystEngComm, 2010, 12, 2243. [2] J. D. Wuest, Chem.Commun., 2005, 5830-5831.

Keywords: pyrazinecarboxamide, crystal engineering, molecular architecture

Keywords: Ruthenium complex, NAD model ligand, Photo-driven reduction

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Acknowledgement: The presented project has been financially supported by the Medical Science National Fund at the Medical University – Sofia (Project 63/2012)

Ruthenium complexes incorporated biological function of nicotinamide adenine dinucleotide redox couple (NAD+/NADH) could be potential candidates for electro- and/or photo-chemical generators of renewable hydride donors to realize six-electron CO2 reduction system. In this context, we have recently demonstrated that a ruthenium complex having a newly designed NAD+/NADH model ligand, [Ru(bpy)2(pbn)](PF6)2 (bpy = 2,2’-bipyridine, pbn = 2-(pyridin-2-yl) benzo[b][1,5]naphthyridine), is efficiently reduced to the corresponding two-electron reduction complex, [Ru(bpy)2(pbnHH)](PF6)2 (pbnHH = 2-(pyridin-2-yl)-5,10-dihydrobenzo[b][1,5]naphthyridine), upon irradiation of visible light in the presence of a sacrificial reagent.[1] This photo-driven hydrogenation using protons has been of crucial interest and importance in the feasibility for the renewable hydride reagent, and this finding has stimulated us to research how to finely control such hydrogenation reaction. We will report herein the synthesis and characterization of ruthenium complexes containing new NAD+ as well as NADH model ligands with modulated twisted distortion of the ligand taking advantage of the substituent effect, namely, [Ru(bpy)2(3Me1-pbn)](PF6)2 (3Me1pbn = 2-(3-methylpyridin-2-yl)benzo[b][1,5]naphthyridine) and [Ru(bpy)2(3Me1-pbnHH)] (PF6)2 (3Me1-pbnHH = 2-(3-methylpyridin2-yl)-5,10-dihydro- benzo[b][1,5]naphthyridine) as the first example for observation of drastic difference in photo-driven NAD+/NADH type hydrogenation reaction of the NAD+ model ligands compared with the case of the nonsubstituted pbn ligand.[2]

Poster Sessions MS.C3.P.466

MS.C3.P.467

Planar Tetrapalladium Complex with Si- and Ge-Ligands and its Unique Properties Kohtaro Osakada, Makoto Tanabe, Naoko Ishikawa, and Mai Chiba, Chemical Resources Laboratory, Tokyo Institute of Technology (Japan). E-mail: [email protected]

Dimethylsulfoxideruthenium(III) Complexes Bearing 2,6-Pyridinedicarboxylate Midori Otsuka, Hiroki Isogai, Sohei Fukui, Hirotaka Nagao, Department of Materials and Life Science, Sophia University, Tokyo, (Japan). E-mail: [email protected]

Multinuclear transition metal complexes containing a planar arrangement of metal centers linked via metal-metal bonds are rare among transition-metal clusters. Recently, we found tetra- palladium complexes, [Pd{Pd(dmpe)}3(m3-EPh2)3] (1: E = Si; 2: E = Ge), which contains a central Pd4Si3 unit composed of four Pd centers and three bridging silylene ligands.1,2 They have rigid and stable structures, but show chemical properties upon addition of organosilanes and Lewis acids. In this paper, we report the reactions of the complexes as well as their physical properties. The addition of an equimolar amount of HSC6H4tBu-4 to a hexane solution of 2 caused the separation of [{Pd3(m-GePh2)2(m-H)(m3GePh2(SC6H4tBu-4))}2(m-dmpe)] (3) as a yellow solid. Complex 3 is composed of two Pd3(m-GePh2)2(m-H)(m3-GePh2(SC6H4tBu-4)) units and a bridging dmpe ligand, as revealed by X-ray crystallography. The isolated hexanuclear complex 3 is thermally stable and does not change its structure in solution even at 60 °C. The addition of dmpe to a benzene-d6 solution of 3 ([dmpe]/[3] = 0.5/1), however, formed a mixture of the tetranuclear complex 2 and [Pd(dmpe)2], which were identified from the 31P{1H} NMR peaks of the solution. Equimolar CuI reacts with complexes 1 and 2 to cause their addition to a Pd–Pd bond to afford the pentanuclear complexes [Pd(m-CuI) {Pd(dmpe)}3(m3-EPh2)3] (4: E = Si, 5: E = Ge). The NMR results of 4 below room temperature show the dynamic behavior of the molecule on the NMR time scale. Detailed measurements revealed that cleavage and formation of a Cu–Pdedge bond occur rapidly and reversibly to cause the apparent pivot motion of CuI on the surface of the Pd4Ge3 plane. The two above reactions are summarized below.

2,6-pyridinedicarboxylate (Hnpydc; n = 0, 1) can coordinate to a metal center as a tridentate or bidentate ligand with pyridyl and carboxylate groups. Dimethyl sulfoxide (DMSO) complexes of ruthenium(III) containing pydc have been synthesized and characterized. The isomeric pair of (C2H5)4N[Ru(pydc)Cl2- (DMSO)], trans(Cl,Cl)- and cis(Cl,Cl)-forms, were synthesized by reactions of (C2H5)4N[Ru(pydc)Cl2(CH3CN)] with DMSO in acetone under stirring or refluxing conditions. The cis(Cl,Cl)-form was also synthesized from the trans(Cl,Cl)-form with heating. These complexes were characterized by cyclic voltammetry, IR spectroscopy, and X-ray crystallograpy. The structure of the trans-form was shown in Figure 1. Both DMSO complexes have a distorted octahedral geometry with two chloride, one pyridine, two carboxylato, and one DMSO which coordinates as a S-bond linkage isomer. The cis-form complex is structually more stable than the trans-form by comparison of bond distances, since coordination of the p-acceptor ligand at a trans position toward a p-donor ligand is favored. In synthetic study, the cis-form complex was synthesized by the reaction of the trans-form with heating. The cis-form complex is more stable than the trans-form. Cyclic voltammagrams (CVs) in acetonitrile of both complexes are similar to those observed for the cis-form and the trans-form complex. CVs of both complexes show reversible waves assigned to a RuIII/RuII couple at -0.51 and -0.56 V and irreversible waves assigned to a RuIV/ RuIII process at 1.04 and 1.11 V (Figure 2).

Figure 1. Structure of trans(Cl,Cl)-[Ru(pydc)Cl2(DMSO)]-

We found that the planar tetrapalladium complexes with bridging Si- and Ge- ligands undergo unique structural change upon the reaction with thiol and CuI. The other reactions of the complexes are also mentioned. [1] T. Yamada, A. Mawatari, M. Tanabe, K. Osakada, T. Tanase, Angew. Chem., Int. Ed. 2009, 48, 568-571. [2] M. Tanabe, N. Ishikawa, M. Chiba, T. Ide, K. Osakada, and T. Tanase, J. Am. Chem. Soc., 2011, 133, 18598-18601.

Keywords: palladium, cluster, Si- and Ge- ligands

Figure 2. CVs of the trans(Cl,Cl)-form (top) and the cis(Cl,Cl)-form (bottom)

Keywords: 2,6-pyridinedicarboxylic acid, dimethyl sulfoxide, geometric isomers

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Poster Sessions MS.C3.P.468 Structure of Bio-Inspired Metal-Arylnitroso Complexes Xavier Ottenwaelder,* Mohammad S. Askari, Department of Chemistry and Biochemistry, Concordia University, Montreal (Canada). E-mail: [email protected] Research on the Cu(I)/O2 reaction has been driven by the intermediacy of Cu/O2 species in the catalytic cycle of several monooxygenase enzymes that can perform difficult oxidation reactions such as the direct insertion of an oxygen atom into a C-H bond. Most catalytic intermediates in such enzymes are, however, too transient to be observed. In parallel, model Cu(I)/O2 reactions performed in solution lead to complexes that are very thermally unstable and difficult to study [1]. Here, we are reporting our investigations on the reaction between electron-rich Cu(I) complexes and arylnitroso compounds (Ar-N=O), which are isoelectronic to dioxygen. The ensuing Cu/arylnitroso complexes are stable at room temperature, and are thus more easily amenable to spectroscopic and crystallographic characterization than their Cu/O2 analogues. The Cu/arylnitroso reaction is subject to selfassembly, as is the Cu/O2 reaction, and the adducts are similar in geometry and electronic structure to known Cu/O2 adducts (picture, A). In one example (picture, B), two crystal structures were obtained from the reaction of [(Me6tren)Cu]X (X = TfO, SbF6) and nitrosobenzene (PhNO) [2]. The two species are Cu(II)-(PhNO•-) radical complexes in which the initial Cu(I) complex reduced nitrosobenzene by one electron akin to the formation of an end-on Cu(II)-superoxide species. These complexes, however, differ in their spin state: singlet (S = 0) for the SbF6 complex and triplet (S = 1) for the triflate complex. Whereas only triplet end-on Cu(II)-superoxide species are known, the present analogues provide a unique opportunity to compare both spin states and evaluate their importance in terms of structure and reactivity.

bonds are recognized to be quite important in controlling chemical reactions occurring at metal centers. In addition, molecular structures also regulate chemical reactivity in the field of redox catalysis [1,2]. Thus combination of the effects of suitable molecular design and the noncovalent interaction network can be used to develop metalmediated transformations. We have explored superior complex systems in this regard. The pyridine-based framework has proven to be a very adaptable building block for the construction of a wide variety of multi-functionalized ligands [3]. In this work, we describe the pyridyl-bridged bis[1,8] naphthyridine (bnp) ligand with general formula trans(L)-[Ru(bnp) L2(OH2)]2+ (L = triphenylphosphine (PPh3) or pyridine (py); Fig. a). Additional complexes involving trans(L)-[Ru(bnp)L2(CO)]2+ (Fig. b) are also prepared. The redox-active bnp is the multi-functionalized polypyridyl ligand which forms noncovalent interactions with a coordinated molecule at equatorial position using its noncoordinating nitrogen atoms and provides a specific reaction site. X-ray analyses of the [Ru(bnp) L2(OH2)]2+ complexes actually indicate one or two H-bonds between the noncoordinating N atom(s) of bnp and the coordinated water. We will present that some reactivities of the complexes are affected by both bnp and axial ligands (L).

Figure Chemical structures of trans(L)-[Ru(bnp)L2(OH2)]2+ (a) and trans(L)-[Ru(bnp)L2(CO)]2+ (b). [1] M. Dakkach, M. I. López, I. Romero, M. Rodríguez, A. Atlamsani, T. Parella, X. Fontrodona, A. Llobet, Inorg. Chem., 2010, 49, 7072-7079. [2] A. D. Chowdhury, A. Das, K. Irshad, S. M. Mobin, G. K. Lahiri, Inorg. Chem., 2011, 50, 1775-1785. [3] D. Oyama, Global J. Inorg. Chem., 2011, 2, 219-251.

Keywords: ruthenium, polypyridyl complex, synthesis and structure

Keywords: metallo-radicals, biomimetic chemistry, self-assembly

MS.C3.P.469 Synergistic Effect of Structures and Noncovalent Interactions in Metal Complexes Dai Oyama,a Takashi Yamanaka,a Ayumi Fukuda,a Tsugiko Takase,b a Department of Industrial Systems Engineering, Fukushima University, Fukushima (Japan). bCenter for Practical and ProjectBased Learning, Fukushima University, Fukushima (Japan). E-mail: [email protected] Noncovalent interactions such as intramolecular hydrogen

MS.C3.P.470 Generation of Novel Ensembles using [3+3] Neutral Metal Selfassembly Approach Amlan K. Pal,a Marie-Pierre Santoni,b Baptiste Laramée-Milette,a Garry S. Hanana and Berni Hasenknopf,b aDepartment of Chemistry, Université de Montréal, Montréal, Québec, (Canada), H3T 1J4. b UPMC-Univ. Paris 6, Institut Parisien de Chimie Moléculaire, UMR CNRS 7201, 75252 Paris cedex 05, (France). E-mail: iitm.amlan@ gmail.com A new rapidly progressing field at the crossroads of chemistry, physics and technology is the supramolecular chemistry of 2D- and 3D- self-assembled molecular architectures.[1] These structures, not only find their application as reaction mediators in host-guest chemistry, but are equally useful in different domains like materials technology, catalysis, data storage and processing, medicinal and green chemistry.[2]

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[1] L.M. Mirica, X. Ottenwaelder, T.D.P. Stack, Chem. Rev. 2004, 104, 10131045. [2] M.S. Askari, B. Girard, M. Murugesu, X. Ottenwaelder, Chem. Commun. 2011, 47, 8055-8057.

Poster Sessions In our ongoing project, the synthesis of ligands containing directionally coordinating heteroatoms and their complexations with coordinatively unsaturated Pd(II) were performed. The self assembly of predesigned polyoxometalates (POMs) and metallic chromophores such as, homoleptic substituted terpyridine complexes of Fe(II), Ru(II)- were facilitated by Pd(II). The synthesis and properties of the new POM and chromophoric assemblies will be presented.[3]

[1] J. K. Klosterman, Y. Yamauchi and M. Fujita, Chem. Soc. Rev., 2009, 38, 1714-1725. [2] M. W. Cooke and G. S. Hanan, Chem. Soc. Rev., 2007, 36, 1466. [3] M.-P. Santoni, A. K. Pal, G. S. Hanan, M.-C. Tang, K. Venne, A. Furtos, P. M.-Tremblay, C. Malveau and B. Hasenknopf, Chem. Commun., 2012, 48, 200, HOT Paper.

Keywords: self-assembly, coordination vectors, supramolecules

MS.C3.P.471 Preparation of Cu(II), Ni(II) and Pd(II) complexes with novel NSdispiro ligand Germán Paparoni, Ricardo R Contreras, Fernando Bellandi, Ángel Gutierrez, Olga Sánchez, Yeraldith Rojas. Laboratorio de Organometálicos, Universidad de Los Andes, Mérida, (Venezuela). E-mail: [email protected] The synthesis and characterization of three metal complexes (Cu(II), Ni(II) and Pd(II)) with novel monodentate [NS]^- ligand 2,4– dispiro(cyclohexane)–8–methyl-carboxydithio–[1,2,3,4,4a,5,6,7]– octahydro-(1H,3H) quinazoline (L^1) is described. The elemental analysis data indicates the formation of 1:1 chelates. The nonelectrolytic behavior of these compounds is evident from their low conductivity values (~ 1 mho cm2 mol-1) in nitrobenzene. Molecular weight determinations (by mass spectrometry) indicates the monomeric composition of the metal complexes with a general formula M(II)L1 (OAc)2. The spectroscopic data (UV-Vis, FTIR, and NMR) are consistent with a square-planar geometry. The electrochemical properties of metal complexes have been investigated by cyclic voltammetry, exhibiting irreversible one electron reduction and oxidations. The spectral and electrochemical properties of the metal complexes are discussed and compared with analogous M(II) [NS]^- complexes. The structure proposed was modeled using the computational calculations employing a semiempirical molecular orbital program (PM3 and PM6). [1] R. R. Contreras, B. Fontal, A. Bahsas, T. Suárez, M. Reyes and F. Bellandi. J. Heterocycles Chem., 2001, 5, 1223-1225. [2] R. R. Contreras, T. Suárez, M. Reyes, F. Bellandi, P. Cancines, J. Moreno, M. Shahgholi, A. Di Bilio, HB. Gray and B. Fontal. Structure and Bondig. 2004, 106, 71-79. [3] EE. Ávila, AJ. Mora, GE. Delgado, R. R. Contreras, L. Rincón, AN. Fitch and M. Brunelli. Acta Cryst. 2009, B65, 639-646.

Keywords: Quinazoline, Cyclic Voltammetry, Computational Chemistry

MS.C3.P.473 Solution and Solid State Dynamics of Metal-Coordinated White Phosphorus Maurizio Peruzzini,a Vincenzo Mirabello,a Maria Caporali,a Vito Gallo,b Luca Gonsalvi,a Dietrich Gudat,c Wolfgang Friy,d Andrea Ienco,a Mario Latronico,b Piero Mastrorilli,a,b aICCOM CNR, Sesto Fiorentino, (Italy). b Dipartimento di Ingegneria delle Acque e di Chimica, Politecnico di Bari (Italy). cInstitut für Anorganische Chemie, Universität Stuttgart (Germany). dInstitut für Organische Chemie, Universität Stuttgart (Germany). E-mail: [email protected] In recent years h1-tetrahedro-tetraphosphorus complexes have become a well known class of compounds and cannot be any more considered simple chemical curiosities among the many metal complexes bearing naked polyphosphorus ligands.[1] The most relevant feature of these species is the rich chemistry they exhibit which appears completely different and more controllable with respect to that shown by the free P4 molecule.[2] Although these species have been characterized by several chemico-physical methods, including crystallographic techniques in the solid state, the elective method to characterize these compounds is the 31P{1H} NMR spectroscopy which easily provide a prima facie evidence for their formation due to the appearance of a typical AM3 pattern at high field. Apart from the free rotation of the P4 tetrahedron around the M-PP axis, these complexes have been considered static in 4 solution in spite that some broadness of the AM3 resonances observed for the iron complex [Cp*Fe(PEt3)2(h1-P4)]PF6 could anticipate a dynamic behavior in solution, which however has not yet been addressed in detail.[3] In this communication we report a detailed 31P{1H} NMR study on several tetraphosphorus complexes which discloses the existence of intriguing fluxional processes occurring for most of the known h1-P4 complexes. The study here presented is aimed at: • ascertaining whether fluxional processes of the coordinated P4 represent a general feature of these class of compounds • verifying whether the possible dynamic motion experienced by the coordinated P4 molecule could still be present in the solid state • finding a rationale explanation of the possible scrambling processes.

Figure: Portion of the 31P{1H} EXSY spectrum of trans-[Ru(dppe)2(H)(η1-P4)]+ (C2D2Cl4, 298 K, td = 0.1 s) [1] M. Caporali, L. Gonsalvi, A. Rossin, M. Peruzzini, Chem. Rev, 2010, 110, 4178 – 4235. [2] M. Di Vaira, M. Peruzzini, P. Stoppioni, Compt. Rend. Acad. Sci. 2010, 13, 935 – 942. [3] I. de los Ríos, J.-R. Hamon, P. Hamon, C. Lapinte, L. Toupet, A. Romerosa, M. Peruzzini Angew. Chem. Int. Ed. 2001, 40, 3910 – 3913.

Keywords: White Phosphorus, NMR spectroscopy, Ruthenium

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MS.C3.P.474

MS.C3.P.475

Structural and Functional Models of [NiFe] Hydrogenases Cyril Pieria, Renaud Hardréa, Bruno Faurea, Pierre-Yves Oraina, Vincent Arterob, Marius Régliera aAix-Marseille Université, ISM2, équipe BiosCiences, avenue de l’escadrille Normandie Niemen, case 342, 13397 Marseille Cedex 20 (France). biRTSV/LCBM, CEA Grenoble,17 rue des martyrs, 38 054 Grenoble cedex 09 (France).E-mail:[email protected]

Gold Dithiophosphonate Complexes Derived from Chiral Diols Michael N. Pillay,a Bernard Omondi,a Richard J. Staples,b and Werner E. van Zyl.a aSchool of Chemistry, University of KwaZulu-Natal, Westville Campus, Durban, (South Africa). bDepartment of Chemistry, Michigan State University, East Lansing, (United States). E-mail: [email protected]

Excepted on platinium electrodes, protons reduction into hydrogen occur with high overvoltages and low energetic yields. However, platinium replacement by new cheap catalysts is of high importance for a widespread use of hydrogen as an energy vector. The nature often intrigues scientists and is fantastic to generate new ideas and solutions. Regarding our field, several enzymes with transition metals, catalyse chemical reactions that would be impossible under normal conditions of working. In particular, a class of metalloproteins, the hydrogenases, are of major interest as they reversibly reduce and oxidize hydrogen. The [NiFe] hydrogenase, in the center of our investigations[1], has an active site containing two metallic centres, Ni and Fe, coordinated by four cysteines, and three Fe-S clusters, located in the proteic core, playing the role of an electron relay. Several drawbacks, as a quick deactivation by gas, led scientists to synthesise a wide variety of bioinspired models in order to find robust and better catalysts, but still associated to high overvoltages, harsh operating conditions and low energetic yields. Our goal is to produce new complexes of nickel, iron and ruthenium, whether mononuclear, binuclear or polynuclear. One parameter that seemed important to us, the polythiolate environment around the nickel, was introduced in our models by synthesing various original poly-thiolate ligands and their corresponding complexes. Different tests as cyclic voltammetry, bulk electrolysis and hydrogen production essays enabled us to evaluate their catalytic properties, from what a new trinuclear polythiolate nickel complex appeared to have a very interesting activity (TOF: 700 s-1, overvoltage: 500 mV) in hydrogen production.

Bifunctional dithiophosphonate ligands were prepared from diols of the isomeric saturated cyclic alkane trans 1,2 cyclohexanediol. Such diols offer new perspectives in forming dithiophosphonates. Thus, reaction of (NH4)2[(S2P-1,4-C6H4OEt)2(trans-1,2-O,O’-C6H10)] with [AuCl(tht)] (tht = tetrahydrothiophene) (molar ratio 1:2) in THF led to the formation of a novel 27-membered metallatriangle of the type [Au2S2P-1,4-C6H4OEt)2(trans-1,2-O,O’-C6H10)]3 1. Metallatriangles containing dinuclear units were hitherto unknown for gold and limited to very few metals in general. Complex 1 exhibits two different types of intramolecular Au···Au interactions and is an ideal candidate for testing of oxidative addition (OA) products. We treated complex 1 with Br2, the dinuclear units circumvented isolable gold(II) formation. Instead, the entire assembly ruptured, forming a structurally characterized dinuclear gold(III) complex [{AuBr2}2(S2P-1,4-C6H4OEt)2(trans-1,2-O,O’-C6H10)] 2 as the stable major product. Complex 2 marks the first square planar gold(III) complex containing both a S-P-S chelate and halogen ligands bonded to the same Au(III) center.

Keywords: gold, dithiophosphonate, metallatriangles

MS.C3.P.476

1) [NiFe] hydrogenase 2) trinuclear Ni model complex [1] Fontecilla et coll., Nature, 1995, 373, 580. [2] D.J. Evans, C.J. Pickett, Chem. Soc. Rev., 2003, 32, 268.

Keywords: Hydrogenases, models, hydrogen

Kinetic and DFT study on C-S bond formation by alkyne addition to the [Mo3S4(H2O)9]4+ cluster J. A. Pino-Chamorro,a Andrés G. Algarra,a Manuel G. Basallote,a M. Jesús Fernández-Trujillo,a Rita Hernández-Molinab. aDepartment of Inorganic Chemistry, Faculty of Science, University of Cadiz, Cadiz (Spain). bUniversity of La Laguna, Tenerife, Islas Canarias (Spain). E-mail: [email protected] The [Mo3S4(H2O)9]4+ (A) cluster has an incomplete cuboidal structure with a capping sulfide ligand coordinated to the three metal

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Poster Sessions

Poster Sessions centers and the other three sulfides acting as bridges between two Mo atoms. The octahedral coordination around each metal center is completed with three molecule of water. Reaction of this cluster with alkynes has been shown to lead to formation of two C-S bonds between the alkyne and two of the bridging sulphides,[1,2] the metal centres playing a passive role despite reactions at those sites are well illustrated for this kind of cluster. A detailed study including kinetic measurements, both in the stopped-flow and conventional UV-Vis time scales, and DFT calculations has been carried out to understand the mechanism of reaction of A with two different alkynes, 2-butin-1,4-diol and acetilenedicarboxilic acid. Stopped-flow experiments indicate that the reaction involves the appearance in a single kinetic step of a band at 855 and 875 nm, depending on the alkyne used, typical of clusters with two C-S bonds. The effects of the concentrations of the reagents, the acidity and the reaction medium on the rate of reaction have been analyzed. Experiments at longer times using a conventional UV-Vis spectrophotometer show the disappearance of this band but satisfactory kinetic results could not be obtained because of precipitation problems.

X= Cl. The metal–metal separation in Tc2Br83- (2.1261(9) Å is identical to that in Tc2Cl83- while it is significantly shorted compared to Tc2Br82-. The structure and bonding in the Tc2X8n- (X = Cl, Br; n = 2, 3) anions has been investigated using multiconfigurational quantum calculations. The structural parameters calculated for the four anions are within 3 % of the experimental values. Effective bond order analysis demonstrates that the four dimers exhibit similar bond multiplicity and to possess an effective triple Tc-Tc bond. The change of electronic configuration does not affect total bond order while it affects the metal-metal bond. Reactions of (n-Bu4N)2Tc2X8 with trimethylphosphine were performed in dichloromethane; the new technetium(II) dimers, Tc2X4(PMe3)4 (X = Cl, Br), were isolated and characterized by single crystal XRD, UV-Visible spectroscopy, and cyclic voltammetry. The metal-metal distances are 2.1317(1) Å for X = Cl and 2.1315(2) Å for X = Br. The UV-Visible spectra were recorded in benzene. Assignment of the bands as well as computing their excitation energies and intensities were performed. Calculations predict that the lowest energy band corresponds to the d* // s* transitions. Keywords: Technetium, Metal-metal bond, Spectroscopy

MS.C3.P.479 A Crystallographic and Kinetic Study of O,O’ Bidentate Vanadium Complexes Carla Pretorius,a Johan A. Venter, Andreas Roodt Department of Chemistry, University of the Free State, Bloemfontein (South Africa). E-mail: [email protected]

[1] T. Shibahara, G. Sakane, S. Mochida, J. Am. Chem. Soc., 1993, 115, 1040810409. [2] Y. Ide, M. Sasaki, M. Maeyama, T. Shibahara, Inorg. Chem. 2004, 43, 602-612.

Keywords: kinetic, C-S bond, cluster

MS.C3.P.477 Study of the Octahaloditechnetate Tc2X8n- (X = Cl, Br; n = 2, 3) Anions and Their Phosphines Derivatives Frederic Poineau,a Paul Forster,a Tanya K. Todorova,b Laura Gagliardi,c Alfred P. Sattelberger,d Kenneth R. Czerwinski,a a Department of Chemistry, University of Nevada Las Vegas, Las Vegas, (USA).bLaboratory for Computational Molecular Design, Ecole Polytechnique Fédérale de Lausanne, Lausanne,(Switzerland). c Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis,(USA).dEnergy Engineering and Systems Analysis Directorate, Argonne National Laboratory, Argonne,(USA). E-mail: [email protected] The technetium dimers (n-Bu4N)2Tc2X8 (X = Cl, Br), [Cs(2+x)] [H3O(1-x)]Tc2Br8 (x = 0.22) and Tc2X4(PMe3)4 (X = Cl , Br), were synthesized and studied by a number of physical and computational techniques. Single crystal XRD of the acetone solvate (n-Bu4N)2[Tc2X8] revealed Tc-Tc distances of 2.1625(9) Å for X = Br and 2.1560(3) Å for

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[VO(acac)2] (acac= acetylacetonate) and related complexes have been successfully synthesized and reported during the past couple of decades. Recent research has shown that vanadium β-diketonates are effective insulin mimicking agents with [VO(acac)2] and [VO(Et-acac)2] (Et-acac= 3-ethyl-2,4-pentane-dionate) in particular showing excellent activity [1], [2]. This discovery, along with other industrial and medical applications, has been the key driving force for research into new frontiers of vanadium coordination chemistry. This study is concerned with the coordinative and structural properties of vanadium complexes in the +4 and +5 oxidation states containing primarily O,O’ bidentate ligands. In addition, different ancillary ligands were selected and coordinated to the vanadium centre to evaluate their structural influence utilizing single crystal X-ray diffraction studies (XRD) in combination with infrared spectroscopy (IR). This has resulted in a new understanding of the solid state characteristics of these complexes and the effect of an altering electronic environment around the vanadium centre on structural properties. A kinetic investigation of the substitution reaction of [VO(O2)2bpy] and 2,3-pyridine dicarboxylate (2,3-dipic) was integrated with the study (see scheme). The complex solution chemistry of vanadium necessitated a wide array of experiments to evaluate the effects of not only ligand concentration on reaction rates, but also pH dependence of certain species in solution. Additionally, 51V NMR experiments revealed important information regarding product formation and the identification of an intermediate, [VO(O2)(2,3-dipic)]2-, in the reaction. This culminated in a proposed reaction mechanism and rate law that accounts for various pH, pKa and concentration effects. Figure 1 illustrates the dependence of the pseudo first-order rate constant on pH and entering ligand concentration.

Poster Sessions single crystal X-ray diffraction and X-ray powder diffraction. The application of these molybdenum complexes as catalysts in olefin epoxidation reveals promising performance for the epoxidation of non-functionalized olefins. [1] P.J. Hargman, D. Hargman, J. Jubieta, Angew. Chem. Int. Ed., 1999, 38, 2638-2684. [2] M. Abrantes, T. R. Amarante, M. M. Antunes, S. Gago, F. A. Almeida Paz, I. Margiolaki, A. E. Rodrigues, M. Pillinger, A. A. Valente, I. S. Gonçalves, Inorg. Chem., 2010, 49, 6865-6873. [3] S. Kodama, A. Nomoto, S. Yano, M. Ueshima, A. Ogawa, Inorg. Chem., 2011, 50, 9942. [4]  T. R. Amarante, P. Neves, C. Tomé, M. Abrantes, A. A. Valente, F. A. Almeida Paz, M. Pillinger, I. S. Gonçalves, Inorg. Chem., 2012, 51, 3666-3676.

[1] J. H. McNeill, V. G. Yuen, H. R. Hoveyda, C. Orvig, J. Med. Chem., 1992, 35, 1489. [2] B. A. Reul, S. S. Amin, J. P. Buchet, L. N. Ongemba, D. Crans, S. M. Brichard, Br. J. Pharmacol., 1999, 126, 467.

Keywords: vanadium, 51V NMR, [2,3-dipic]

MS.C3.P.480 Synthesis and Structure of New Oxomolybdenum Hybrid Materials Tatiana R. Amarante,a Patrícia Neves,a Anabela A. Valente,a Filipe A. Almeida Paz,a Martyn Pillinger,a Isabel S. Gonçalves,a aDepartment of Chemistry, University of Aveiro, 3810-193 Aveiro, (Portugal). E-mail: [email protected] Oxomolybdenum hybrid materials have been of interest for several years due to their catalytic, magnetic, electronic, and optical properties [1]. One class that has attracted particular interest is the one in which the organic component is an organonitrogen compound. Molybdenum oxide/organoamine hybrids are generally prepared by the hydrothermal treatment at 160−200 °C of aqueous solutions containing the organonitrogen compound and the molybdenum source, which is usually Na2MoO4, MoO3, or (NH4)6Mo7O24. This method frequently affords crystals suitable for X-ray diffraction. On the other hand, yields can be low, and mixtures of phases are sometimes obtained. We have been exploring alternative approaches that use monomeric molybdenum complexes as precursors. The controlled hydrolysis and condensation of monomeric complexes of the type MoO2Cl2L is one potentially interesting route to molybdenum oxide/organic hybrids. An example is the reaction of MoO2Cl2(2,2′-bipy) with water at 100−120 °C which affords the material {[MoO3(2,2′-bipy)][MoO3(H2O)]}n with a crystal structure containing 1D inorganic and organic−inorganic polymers linked by O−H···O hydrogen bonds [2]. As part of our on going investigations into the use of molybdenum complexes as precursors to oxomolybdenum hybrids, we report on results with the complex [MoO2Cl2(di-tBu-bipy)] (di-tBu-bipy = 4,4’-di-tert-butyl2,2’-bipyridine). According to the literature, di-tBu-bipy is a good choice as a ligand for oxometal complexes which will be used as catalysts for oxidation reactions [3]. The reaction of [MoO2Cl2(ditBu-bipy)] with water by three different methods gave the octanuclear complex [Mo8O22(OH)4(di-tBu-bipy)4] as a microcrystalline powder [4]. Single crystals, suitable for X-ray diffraction, were only obtained by the reaction of MoO3 and di-tBu-bipy in water in the mole ratio of 1:1:580 at 160 ºC for 3d. When the filtered solution from this reaction was evaporated to dryness a dinuclear complex [Mo2O6(di-tBu-bipy)2] was reproducibly obtained as microcrystalline powder; single crystals were obtained by slow evaporation of the filtered solution at room temperature. Both complexes were structurally characterized by

Keywords: molybdenum epoxidation

oxides,

hybrid-materials,

olefin

MS.C3.P.482 Synthesis and Electronic Structure of Heterometallic CarbideBridged Complexes Anders Reinholdt,a Johan Vibenholt,a Magnus Schau-Magnussena Jesper Bendixa aDepartment of Chemistry University of Copenhagen, Copenhagen (Denmark). E-mail: [email protected] The recent discovery[1,2], that the the FeMoco cofactor of nitrogenase contains a carbon-centered iron cluster is surprising in view of the unprecedented structure and the relative scarcity of carbide-bridged systems. Furthermore, there appears to be no reported examples of synthesis of carbide-bridged systems in aqueous solution. It is, accordingly, of interest to devise targeted syntheses of carbide-bridged poly-nuclear complexes. We report a general route to heterobimetallic carbide-bridged systems starting from terminal carbide complexes of ruthenium and osmium. The systems have been investigated spectroscopically and computationally and it has been shown that the terminal carbide complexes can be viewed as strong p-acceptor ligands towards other metal centers. In this respect terminal carbide complexes closely resemble analogous terminal nitrido complexes.[3,4]

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Figure 1: Three-dimensional plot showing the dependence of the pseudo first-order rate constant on pH and [2,3-dipic].

We are grateful to FCT, the POCI 2010, OE, and FEDER for general funding (project PTDC/QUI/65427/2006) and for financial support (FCT) towards the purchase of the single-crystal diffractometer. We acknowledge FCT for grants to T.R.A. and P.N. (SFRH/BD/64224/2009 and SFRH/BPD/73540/2010).

Molecular structure of [(cy3P)2Cl2Ru(m-C)PtCl3]- synthesized from Zeises salt and a terminal carbido precursor of ruthenium.

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Poster Sessions [1] K. M. Lancaster, M.Roemelt, P.Ettenhuber, Y. Hu, M. W. Ribbe, F. Neese, U. Bergmann, S. DeBeer Science, 2011, 334, 974-977. [2] T. Spatzal, M. Aksoyoglu,, L. Zhang, S. L. A. Andrade, E Schleicher, S. Weber, D. C. Rees, O. Einsle Science, 2011, 334, 940. [3] J. Bendix, C.Anthon, M. Schau-Magnussen, T. Brock-Nannestad, J. Vibenholt, M. Rehman, S. P. A. Sauer, Angew. Chem., Int. ed. 2011, 50, 4480-4483. [4] E. D. Hedegaard, M. Schau-Magnussen, J. Bendix Inorg. Chem. Comm. 2011, 14, 719-721.

Keywords: carbido, heterobimetallic, p-acceptor

MS.C3.P.483 1,10-Phenanthroline Adducts of the Tin(II) Halides: Different Stoichiometry’s, Types of Chemical Bonds, and Coordination Geometries Hans Reuter, Markus Imwalle, Natalia Röwekamp-Krugley, Simona Schröder, Institute of Chemistry, University of Osnabrück, Osnabrück, (Germany). E-mail: [email protected] The Lewis-acid behaviour of the tin(II) halides, SnHal2 with Hal = F, Cl, Br, and I, is well established in the coordination chemistry of main group metals and ligands known to make coordination compounds with tin(II) halides cover mono-, bi- and multidentate ligands mainly containing oxygen or nitrogen atoms as Lewis bases. Structural investigations, however, are often limited to one specific halide and its complex with one specific ligand making it difficult to expand these unique observations to all other halides. In order to close this gap, we let react all tin(II) dihalides with the bidentate nitrogen ligand 1,10-phenanthroline (phen). In this case, only the compound SnCl2(phen) [1] was structurally characterized before. In the course of our study we were able to synthesize and characterize the following coordination compounds: 3SnF2 ∙ phen, 1, SnCl2 ∙ phen, 2, and SnHal2 ∙ 2phen with Br, 3, respectively I, 4. In 1 two SnF2 units form a centrosymmetric dimer via fluorine bridges. Each exocyclic fluorine atoms coordinates to a further SnF2 unit, whereas the coordination sphere of the inner tin atoms is completed by two SnF2(phen) units. 2 represents a molecular coordination compound, SnCl2(phen), with a pseudo trigonal-bipyramidal coordination at tin and the nitrogen atoms of the phenanthroline ligand in axial and equatorial positions. 3 and 4 are ionic coordination compounds each composed of a pseudo trigonal-bipyramidal [Sn(phen)2]2+ cation and two Hal- anions.

[1] S.J. Archer, K.R. Koch, S. Schmidt, Inorg. Chim. Acta, 1987, 126, 209-218.

Keywords: coordination compounds, 1,10-phenanthroline, tin(II) halides

MS.C3.P.484 From Face-Capped to Meridional Ru(II) Complexes as Potential Anticancer Agents Ana Rilak,a,b Živadin D. Bugarčić,a Ioannis Bratsos,b Enzo Alessio,b Enio Zangrando,b aFaculty of Science, University of Kragujevac, R. Domanovića 12, P. O. Box 60, 34000 Kragujevac (Serbia). bDept Scienze Chimiche e Farmaceutiche, Università di Trieste, Via L. Giorgieri 1, 34127 Trieste (Italy). E-mail: [email protected] Most of the recent research in the field of the metal anticancer drugs has focused on organoruthenium half sandwich compounds, many of which were found to possess antiproliferative activity [1]. In particular, the so-called “piano-stool” Ru(II) compounds of the general formula [Ru(η6-arene)(en)Cl][PF6] (en=ethylenediamine) showed promising antitumor activity both in vitro and in vivo. Their activation is believed to involve the dissociation of the Cl, while the presence of en seems to play also a crucial role for their activity. More recently, the half sandwich Ru(II) compound [Ru([9]aneS3)(en)Cl]+ ([9] aneS3=1,4,7-trithiacyclononane), the coordination counterpart of the organometallics (only the arene ring is replaced by the neutral 6-electron donor face-capping ligand [9]aneS3), found to display some activity as well [2]. Both categories share common structural features: they contain a tridentate ligand in facial configuration (either arene or [9]aneS3), a chelating ligand (en) and a monodentate leaving group (Cl). On the other hand, very little is known in the literature for the antitumor activity of complexes bearing a tridentate ligand in meridional geometry while the other ligands remain unchanged. Thus, we developed a series of compounds of the general formula [Ru(mtl) (chel)(X)][Y]n (mtl=2,2’,6’2’’-terpyridine (tpy) or substituted tpy; chel=N-N or N-O chelating ligands; X=Cl or dmso-S; Y=Cl or PF6; n depends on the nature of chel and X) as potential antitumor agents. The structural features of these new complexes, the studies on their chemical behaviour in aqueous solution and on their interaction with biologically relevant ligands will be presented, as well as the future perspectives.

Acknowledgements Financial support from the University of Trieste (CSIUT Research Fellowship) to A.R. is acknowledged. [1] G. Süss-Fink, Dalton Trans., 2010, 39, 1673-1688. [2] B. Serli, E. Zangrando, T. Gianferrara, C. Scolaro, P. J. Dyson, A. Bergamo and E. Alessio, Eur. J. Inorg. Chem., 2005, 3423-3434.

Keywords: ruthenium, anticancer, terpyridine

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Poster Sessions MS.C3.P.485 Single Insertion of a-Olefins into the M-C Bond of Metallaaziridinium Ion Pairs Luca Rocchigiani, Gianluca Ciancaleoni, Cristiano Zuccaccia, Alceo Macchioni. Chemistry Department, University of Perugia, (Italy). E-mail: [email protected] The insertion of olefin into the metal-carbon bond is the elemental step of the Ziegler-Natta catalysis that, in the homogeneous phase, occurs through the initial association of the olefin with the metal cation of the catalytic ion pair. Group IV metallocenium ion pairs polymerize olefins with high rates, but the elevate reactivity of such systems dramatically complicates fundamental kinetic investigations. During our studies on the self-aggregation of zirconocenium ion pairs [1], [2], we synthesized some metallaziridines having [Cp2M(h2-CH2-NR1R2)] [X] general formula, which show some remarkable requisites to be used as good models for investigating the single insertion of olefin into the M-C bond. In particular, they are able to react stoichiometrically with a-olefins (like 1-hexene and 2-methyl-1-heptene) leading to a five-membered azametallacycle, as represented in figure. With the aim of obtaining thermodynamic activation parameters of the single insertion and determining as they depend on nature of counterion and solvent, low-temperature kinetic NMR studies of the reaction of 2-methyl-1-heptene with [Cp2Zr(h2-CH2-NMePh)][X] [1a:X–=MeB(C6F5)3–; 1b:B(C6F5)4–] ion pairs were performed. Results indicate that, in toluene, DH‡ is higher for MeB(C6F5)3– than for B(C6F5)4– (DDH‡=-4.5 kcal mol-1) but the former better compensates the loss of entropy caused by olefin association (DDS‡=-13 cal mol-1 K-1). The two ion pairs 1a-b behave exactly the same in a toluene/ chlorobenzene mixture due to the coordination of a chlorobenzene molecule at the zirconium center that pushes the counterion in the second coordination sphere. DH‡ (ca 11 kcal mol-1) is higher than in toluene (DH‡=8.5 kcal mol-1 and DH‡=4.0 kcal mol-1 for 1a and 1b, respectively) while DS‡ (ca -26 cal mol-1 K-1) is similar to that of 1a in toluene (DS‡=-32 cal mol-1 K-1).[3] We investigated also the tridimensional structure in solution of the formed azapentametallacycles and the fluxional processes present in some of the reaction products by means of NOE NMR techniques. All the experimental findings were flanked by DFT calculations.

The main research activity of the coordination and organometallic research group in the U. of Almeria is the synthesis of new water-soluble organometallic ruthenium compounds and the study of their properties in water. Water is the world solvent, most of the natural systems contain water and it is also an excellent solvent for chemical synthesis. One of our most interesting results was the first example of the watersoluble heterometallic-polymeric complex {[(PTA)2CpRuDMSO]-mAgCl2-}n [1], in which organometallic-metal-complex moieties build the backbone-polymeric chain. Time after, we presented also the water soluble, air stable hetero-poly-metallic polymer {[{(PTA)2CpRu−mCN−RuCp(PTA)2}-m-Au(CN)4-]}n [2]. Both complexes display interesting new properties never found for organometallic complexes as, for example, that they are gels in water. Encouraged by these results, our research activity was focused in obtaining new examples of this family of complexes including a variety of transition metals as linking agents between [{(PTA)2CpRu−m-CN−RuCp(PTA)2] moieties. Herein we report new members of this family of compounds with formula {[{(PTA)2CpRu−m-CN−RuCp(PTA)2}-m-MCl3-]}n (M=Co, Cd, Ni, Cu, Pt and Pd) and their catalytic, biological, optical and gel properties in water.

Crystal Structure of {[(PTA)2CpRu−CN−RuCp(PTA)2]-CdCl3-}n [1] Lidrissi, C.; Romerosa, A; Saoud, M.; Serrano-Ruiz, M.; Gonsalvi, L.; Peruzzini, M.; Angew. Chem. Int. Ed. 2005, 44, 2568-2572. [2] Serrano, M.; Romerosa, A.; Sierra-Martin, B.; Fernandez, A.; Angew. Chem. Int. Ed. 2008, 47, 1-6. Acknowledgements. Financial support co-financed by the EU FEDER: the Spanish MICINN (CTQ2010-20952) and Junta de Andalucía through PAI (research teams FQM-317) and Excellence Projects P07-FQM-03092 and P09FQM-5402. Thanks are also given to COST Action CM0802 (WG2, WG3, WG4). N. Jadagayeva thanks to AECI for a MAE grant and M. S. Ruiz is grateful to Excellence project P09-FQM-5402 for a postdoctoral contract.

[1] L. Rocchigiani, C. Zuccaccia, D. Zuccaccia, A. Macchioni Chem .Eur. J. 2008, 14, 6589-6592. [2] L. Rocchigiani, G. Bellachioma, G. Ciancaleoni, A. Macchioni, D. Zuccaccia, C. Zuccaccia Organometallics 2011, 30, 100-114. [3] L. Rocchigiani, G. Ciancaleoni, C. Zuccaccia, A. Macchioni, Angew. Chem. Int. Ed. 2011, 50, 11752-11755.

Keywords: NMR, metallocenes, ion pairs

MS.C3.P.486 Water Soluble Organo-heterometallic Polymeric Complexes Containing 3,5,7-triaza-phosphaadamantane (PTA) Antonio Romerosa, Franco Scalambra, Nazira Jadagayeva, Manuel Serrano-Ruiz, Luis Aguilera. Área de Química Inorgánica-CIESOL, Universidad de Almería, 04120, Almería (Spain). E-mail: romerosa@ ual.es

MS.C3.P.487 Formation of Transition Metal Complexes with Functionalized Dithiolato Ligands Susanne Ruppel,a F. Ekkehardt Hahn,a aInstitut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstr. 30, 48149 Münster (Germany). E-mail: susanne.ruppel@ uni-muenster.de The syntheses of siderophores and analogue catecholamines are still of academic interest due to their ability as powerful and selective iron chelators. Most of these polydentate chelate ligands are based on oxygen donor groups. Recently we became interested in the synthesis and chemistry of sulphur containing ligands possessing the siderophore topology.[1] Such types of ligands with three benzene-o-

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Keywords: heteropolymetallic-organometallic-polymer complexes, water, gel properties

Poster Sessions dithiolato (bdt2–) subunits are of interest due to the observation that the coordination geometry of molybdenum, tungsten and rhenium derivatives of type [MIV/V/VI(bdt)3]n– (M = Mo, W, Re; n = 0, 1, 2) varies with the formal oxidation state of the transition metal center. This geometry change is easily accomplished in complexes with three bidentate bdt2– ligands, whereas the situation differs for complexes with substituted and linked bdt2– donor groups. A comparison with analogues complexes based on a 2,3-dithiolatobenzamide ligand [M(1)3]n– with complexes that bear a tripodal ligand [M(2)]n– shows the influence of the rigid backbone on the structural and electronic properties. Fig 1. Coordination environment of the two Gd3+ ions in {[Gd2(PDA)3(H2O)]·2H2O}n complex [1] L. Pan, K.M. Adams, H.E. Hernandez, X. Wang, C. Zheng, Y. Hattori, K. Kaneko, Journal of American Chemical Society, 2003, 125, 3062-3067. [2] Z. Chen, W. Xiong, Z. Zhang, F. Liang, Zeitschrift für Anorganische und Allgemeine Chemie, 2010, 636, 1392-1396.

Keywords: 1,4’-phenylenediacetic acid-1, lanthanide complexes-2, crystal structure-3

MS.C3.P.490 [1] a) B. Birkmann, W. W. Seidel, T. Pape, A. W. Ehlers, K. Lammertsma, F. E. Hahn, Dalton Trans. 2009, 7350–7352; b) F. Hupka, F. E. Hahn, Chem. Commun. 2010, 46, 3744–3746.

Keywords: Dithiolenes / Electronic Properties / X-ray diffraction

MS.C3.P-488 A novel Gd(III) Complex Based on 1,4-Phenylenediacetic Acid Zofia Rzączyńska,a Iwona Rusinek,a Justyna Sienkiewicz-Gromiuk,a Liliana Mazur,a aDepartment of General and Coordination Chemistry, UMCS, Lublin, (Poland). E-mail: [email protected] To date, only a few lanthanide(III) coordination polymers on the strength of 1,4-phenylendiacetatic ligand were obtained, namely the isostructural coordination compounds of La(III), Nd(III), Sm(III) and Er(III) ions [1, 2]. The titled compound was subjected to crystal X-ray diffraction, FT-IR, thermal and luminescent studies. Fig. 1 shows the metal coordination environment and the coordination modes of PDA2- in [Gd2(PDA)3(H2O)]·2H2O complex. Single crystal X-ray diffraction analysis revealed that, every asymmetric unit contains two crystallographically independent Gd(III) ions, two complete PDA2ligands and two half PDA2- ligands, one coordinated water molecule and two uncoordinated water molecules. The surroundings around Gd1 consist of eight carboxylato oxygen atoms from six PDA2- ligands and one water molecule. The Gd2 ion is coordinated by nine carboxylato oxygen atoms from six PDA2- ligands. In the polymeric structure of [Gd2(PDA)3(H2O)]·2H2O, the Gd(III) ions are interconnected through –COO- groups, forming triple helix. Each one-dimensional metal carboxylato chain is linked to another four ones through the –CH2C6H4CH2– spacers of the PDA2- ligands, producing a three-dimensional metal-organic framework.

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New Coproporphyrins and their Metal Complexes Elena Savinkina,a Gelii Ponomarev,b Aleksandr Volov,c Ilia Zamilatskov,c Mikhail Grigoriev,с Lubov Obolenskaya,a Aslan Tsivadze,c aLomonosov University of Fine Chemical Technology, Moscow (Russia). bOrekhovich Institute of Biomedical Chemistry of Russian Academy of Medical Sciences, Moscow (Russia). cFrumkin Institute of Physical Chemistry and Electrochemistry of Russian Academy of Sciences, Moscow (Russia). E-mail: [email protected] Coproporphyrins and their metal complexes are promising compounds which can be used as multiparametric sensors for bioassay. Photosensitization with porphyrins and metal porphyrinates is an important way to excite titania (which can be used for energy conversion and photodegradation of many contaminants under UV radiation) to the wavelength of visible light. Two new coproporphyrins H2Por were synthesized by condensation of brom-substituted dipyrrylmethenes and substituted dipyrrylmethanes. They react with platinum(II) and palladium(II) chlorides in PhCN producing corresponding metal coproporhyrinates MPor (M = Pd, Pt). The complexes were characterized by various spectroscopic methods (UV/vis; 195Pt, 13C and 1H NMR; MALDI TOF). Single crystals of MPor (M = Pd, Pt) for one of the synthesized coproporphyrins (left formula) were grown by isothermal concentration in the CH2Cl2/EtOAc and CH2Cl2/Acetone systems for 5 days. Their crystal structures were studied by X-ray diffraction. Crystals are monoclinic, space group P21/c. Unit cell parapmeters for C48H60N4O8M are a = 5.3701(10) and 5.3661(3) Å, b = 14.940(4) and 14.9404(11) Å, c = 29.105(8) and 29.201(2) Å, β = 91.048(5)° and 90.8910(10)° for M = Pd, Pt, respectively; Z = 2. The MPor complexes were used as sensitizers for titania nanoparticles; the prepared samples show photocatalytic activity under visible light.

Poster Sessions MS.C3.P.492 Mixed-Pacman-Complexes as Starting Point for Enzyme Modelling Matthias Schwalbe,a aInstitute of Chemistry, Humboldt-Universität zu Berlin, Berlin, (Germany). E-mail: [email protected]

Keywords: coproporphyrins, palladium, platinum

MS.C3.P.491 Synthesis, Characterization and Structure of Iridium Mono-and Dihydride Complexes Serge Schreiner,a Sydney Schreiner,b aDepartment of Chemistry, Randolph-Macon College, Ashland, Virginia (USA). bDepartment of Chemistry, Davidson College, North Carolina (USA). E-mail: [email protected] The activation of small molecules by transition metal complexes via ligand substitution or oxidative-addition has historically received a great deal of attention since these reactions are requisite for catalytic processes. While chlorocarbonylbis(triphenyl- phosphine) iridium(I) (Vaska’s compound) [1] and some related isoelectronic and isostructural complexes of the type trans-[M(A)(CO)L2] (M = Ir, Rh; A = anionic ligand; L = monodentate tertiary phosphine) have been examined in great detail, much less is known regarding the activation of small molecules by similar planar iridium(I) and rhodium(I) complexes containing bidentate alkyl or aryl phosphine ligands [2]. Our work focused on the synthesis and reactivity of iridium complexes stabilized by the aryldiphosphine, (C6H5)2PCH2P(C6H5)2, [3] and the alkyl diphosphine, (C6H11)2PCH2P(C6H11)2 [4]. We have prepared several iridium-diphosphine-diene complexes which are capable of activating molecular hydrogen and hydrochloric acid resulting in some novel mono – and dihydrido complexes with retention of the diene ligand. Reaction of the iridium-diphosphinediene complexes with CO led to the loss of the diene generating a series of new mono- and dinuclear iridium carbonyl complexes [5].

The activation of oxygen and oxygen-derived species is a major task of natural metallo-enzymes (e.g. heme-oxidase enzymes). A mimic of those natural metallo-enzymes is an obvious starting point, with some precedence, to get more insight into the role that metal ions play in activating oxygen [1]. Very often, the catalytic active center is comprised of two metal atoms that are arranged in close proximity to allow for a combined interaction with substrate molecules [2]. In the field of activating dioxygen the Pacman architecture showed excellent performance characteristics. Due to synthetic constraints symmetric Pacmans including two porphyrinic units were produced preferably. Some rare examples of the combination of two different porphyrins or porphyrin/corrole systems exist, too [3]. But the combination of two very different metal coordination sides is still unknown. We will present the synthesis, as well as, the spectroscopic characterisation of Mixed Pacman type compounds. In a Lego-like reaction sequence based on consecutively palladium cross-coupling reactions we were able to establish a general synthetic route to create Mixed-Pacman-Compounds and will present first structurally characterised metal complexes. As a first example, a terpyridine unit was connected with a porphyrin unit via a xanthene backbone (see scheme below). The results gained in this study allow for high variability and the development of multiple compounds for enzym modelling and the study of the activation of oxygen and oxygenderived species in the future.

[1] I. Ivanovic-Burmazovic, R. van Eldik, Dalton Trans., 2008, 5259. [2] a) J. Rosenthal, D. G. Nocera, Acc. Chem. Res., 2007, 40, 543; b) Z. Halime, M. T. Kieber-Emmons, M. F. Qayyum, B. Mondal, T. Gandhi, S. C. Puiu, E. E. Chufan, A. A. N. Sarjeant, K. O. Hodgson, B. Hedman, E. I. Solomon, K. D. Karlin, Inorg. Chem., 2010, 49, 3629. [3] a) M. A. Filatov, R. Guilard, P. D. Harvey, Org. Lett., 2010, 12, 197; b) K. M. Kadish, L. Fremond, J. Shen, P. Chen, K. Ohkubo, S. Fukuzumi, M. El Ojaimi, C. P. Gros, J.-M. Barbe, R. Guilard, Inorg. Chem., 2009, 48, 2571 and references therein.

MS.C3.P.493

[1] L. Vaska and J. W. Diluzio, J. Am. Chem. Soc., 1962, 84, 679. [2] R. J. Puddephatt, Chem. Soc. Rev., 1983, 12 (2), 99. [3] H. R. Lucas, Senior Thesis, Randolph-Macon College, 2002. [4] S. Garcia, Senior Thesis, Randolph-Macon College, 2010. [5] S. Schreiner, S. Schreiner, unpublished results, 2011.

Keywords: iridium, diphosphine, hydride

Sterically Constricted Ligand, 3,3’-Bis(2-b3nzimidazolyl)-2,2’Bipyridine, Stabilizing Tetrahedral Coordination Geometry Abdurrahman Şengül, Zonguldak Karaelmas University, Faculty of Arts and Sciences, Department of Chemistry, 67100 Zonguldak (Turkey). E-mail: [email protected] Sterically hindered ligands which can impose a pseudotetrahedral geometry on metal ions are of great interest for a variety of reasons [1]. Copper(I), with the d10 electronic configuration, adopts preferentially tetrahedral coordination geometry, whereas Cu(II), with d9 electronic configuration, adopts penta- or hexa-coordination

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Keywords: enzym-modelling, Mixed-Pacman, synthesis

Poster Sessions [2]. Thus, upon oxidation of Cu(I) to Cu(II), a large structural change occurs; consequently, imposition of a particular geometry on the metal allows control of the copper(I)-copper(II) redox couple [3]. System for which this process does not occur are very rare [2]. Among the tetrahedrally-enforcing ligands, 3,3’-bis(2-benzimidazolyl)-2,2’bipyridine (L) incorporating two benzimidazole units linked together through 2,2’-bipyridine is an optimal choice for achieving a tetrahedral environment, vide infra (Figure 1). The present study reports another rare example for a nearly tetrahedral CuI/CuIIN4 redox pair containing the same ligands. In order to make a comparison with the reported metal complexes, the free ligand and its complexes with Cu(I), [Cu(L)2]PF6⋅7H2O⋅CH3OH (1) and Ag(I), [Ag(L)2]OTf⋅H2O (2) were prepared and crystallographically characterized; electrochemical and spectroscopic studies were also performed.

We synthesized the Co(II) complexes via the following two different procedures: (1) Ligand L was mixed with CoCl2 in DMF under Ar. After removing the solvents, the resulting solid was recrystallized from CH2Cl2/Et2O to afford a purple single crystal. (2) Ligand L and Co(ClO4)2･6H2O were dissolved in acetonitrile under Ar atmosphere. After removing the solvents, the crude material was recrystallized from MeCN, CH2Cl2/Et2O to give a pink single crystal. X-ray structural analyses were performed for them. The ORTEP views were depicted in Figs. 2a and 2b. Both of the Co(II) centers had an octahedral structure with L in the equatorial plane and two anions at the axial positions. Oxidation of the [CoCl2(L)] by [Cp2Fe]PF6 was also carried out. Elemental analysis of the oxidized complex suggested that it consisted of L, two chloride ions, PF6- and Co3+ ion. In this presentation, we will also discuss the hydration reaction of nitrile using the Co complexes.

Fig. 1 Structure of N2S2-type ligand L Figure 1.. The molecular structure of [Cu(L)2]PF6⋅7H2O⋅CH3OH (1) 1] J.A. Connor, M. Charlton, D.C. Cupertino, A. Lienke, M. McPartlin, I.J. Scowen, P.A. Tasker, J Chem Soc Dalton, (1996) 2835-2838. [2] D.V. Scaltrito, D.W. Thompson, J.A. O’Callaghan, G.J. Meyer, Coordination Chemistry Reviews, (2000) 208, 243-266. [3] J. McMaster, R.L. Beddoes, D. Collison, D.R. Eardley, M. Helliwell, C.D. Garner, Chem-Eur J, (1996) 2, 685-693.

Fig. 2 ORTEP views of [CoCl2(L)] (a) and [Co(ClO4) (L) (MeCN)] + (b)

Keywords: benzimidazole, tetrahedral, complex

[1] For example: D. S. Rodney, M. K. Coggins, W. Kaminsky, J. A. Kovacs, J. Am. Chem. Soc., 2011, 133, 3954–3963.

MS.C3.P.494

Keywords: complex, cobalt, nitrile

Syntheses and Characterization of N2S2-Type Co(III) Complex with Coordination Environment Similar to Nitrile Hydratase Active Site Structure Mikako Shinmura, Tomohiko Inomata, Yasuhiro Funahashi, Tomohiro Ozawa, Hideki Masuda, Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology (Japan). E-mail: [email protected] Nitrile hydratase (NHase) catalyzes hydration of nitriles to the corresponding amides (reaction 1). R-C≡N + H2O → R-C(O)NH2 (1) Crystal structure analyses of NHases have revealed that the active sites include an octahedral Fe(III) or Co(III) ion with two deprotonated amide nitrogens and three cystidyl sulfurs, two of which are post-translationally oxidized to sulfinate and sulfonate. We have investigated the relationship between the active site structure and reaction mechanism using model complexes. However, we could not obtain any evidences that nitrile molecules interact with metal complexes, which is explained by the consideration that the strong donative ligands have lowered the Lewis acidity of the metal center. In this study, we designed and synthesized a new N2S2-type ligand (L; Fig. 1) with the aim of construction of a biomimetic catalyst for nitrile hydration, which is similar to the coordination environment of NHase active site structures. Considered that the donor atoms of this ligand are all neutral, the ligand used here may have a small electron donating property. We employed Co(III) ion as the metal ion in this study, because it often shows a nitrile hydration [1] and is often used as a metal ion in the model complexes of the NHase active center.

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MS.C3.P.495 Synthesis and characterization of NaI and CoII biphenyl-4,4’diacete complexes Justyna Sienkiewicz-Gromiuk,a Halina Głuchowska,a Liliana Mazur,a Bogdan Tarasiuk,b Zofia Rzączyńska,a aDepartment of General and Coordination Chemistry, UMCS, Lublin, (Poland). bDepartment of Organic Chemistry, UMCS, Lublin, (Poland). E-mail: justuanka@ poczta.onet.pl Synthesis of metal-based coordination polymers with novel properties constitute an important area of research. Coordination polymers (PCPs) represent a unique class of crystalline open framework solids with unprecedented structures and diverse chemical composition [1, 2]. This kind of compounds result from molecular reactions between metal ions and bridging multidentate organic ligands [3]. The biphenyl-4,4’-diacetic acid (H2bbo) shows several features, namely: (1) special arrangement of two carboxyl groups lying at two opposite sites results in the less space hindrance; (2) biphenyl groups may form rigid frameworks and larger cavities; (3) ligand molecules interact actively with water molecules via hydrogen bonds. The new crystal structure of free biphenyl-4,4’-diacetic ligand and its two diverse metal-organic coordination polymers containing sodium(I) or cobalt(II) ions, {[Na4(bbo)2·4H2O]}n, {[Co2(bbo)2·8H2O]}n (Fig. 1), where bbo = [C14H14(COO)2]2-,­have been synthesized and structurally characterized by single-crystal X-ray diffraction, FT-IR spectroscopy, thermal analysis and coupled TG–FT-IR technique. Additionally the

Poster Sessions magnetic susceptibility measurements were performed for cobalt(II) complex.

MS.C3.P.497 Copper(I) Complexes of Acyclic P,N,N’,P’-Ligands for Sustainable OLED Devices Umut Soydaner, Edwin C. Constable, Catherine E. Housecroft, Markus Neuburger, Jennifer A. Zampese, Dept. of Chemistry, University of Basel, Basel, Switzerland. E-mail: [email protected]

Fig 1. Coordination environment of the two Co2+ ions in {[Co2(bbo)2·8H2O]}n complex [1] S. Kitagawa, R. Matsuda, Coordination Chemistry Reviews, 2007, 251, 24902509. [2] O.M. Yaghi, M. O’Keeffe, N.W. Ockwig, H.K. Chae, M. Eddaoudi, J. Kim, Nature, 2003, 423, 705-714. [3] E. Neofotistou, C.D. Malliakas, P.N. Trikalitis, Chemistry – A European Journal, 2009, 15, 4523-4527.

Keywords: biphenyl-4,4’-diacetic acid-1, crystal structures-2, coordination polymers-3

Organic light-emitting devices (OLEDs) based upon transition metal or lanthanide metal emitters or sensitizers have attracted a great deal of attention due to their potential use in lighting as well as future panel display applications [1]. In recent years, copper(I) complexes showed promising results as a sustainable alternative to the traditionally adopted lanthanide emitters or sensitizers and the external quantum efficiency and up to 16% has been realized [2]. With the goal of optimizing light emitting properties of copper(I) complexes, we have synthesized a family of P,N,N’,P’-type ligands of the type shown below along with their mononuclear copper(I) complexes. The properties of these complexes and structure-property relationships will be presented.

MS.C3.P.496 Synthesis of Supramolecular Clusters with the [Al(acacmpy)3] molecular brick Damien Simond,a Céline Besnard,a Alan F. Williams,a aDepartment of Inorganic and Analytical Chemistry, University of Geneva, Geneva, (Switzerland). E-mail: [email protected]

[1] Oms O.; Jarrosson T.; Tong L. H; Vaccaro A.; Bernardinelli G.; Williams A. F. Chem. Eur. J. 2009, 15, 5012-5022. [2] Duriska M. B.; Neville S. M.; Lu J.; Iremonger S. S.; Boas J. F.; Kepert C. J.; Batten S. R. Angew. Chem. Int. Ed. 2009, 48, 8919-8922.

Keywords: self-assembly, ditopic ligand, conductimetry

[1] M. A. Baldo, M. E. Thompson, S. R. Forrest, Pure Appl. Chem. 1999, 71, 2095. [2] Q. Zhang, Q. Zhou, Y. Cheng, L. Wang, D. Ma, X. Jing and F. Wang, Adv. Funct. Mater. 2006, 16, 1203.

Keywords: copper(I) complexes, ligand design, luminescence

MS.C3.P.498 Activation of Dinitrogen by Low-valent Iron Stephen Sproules,a Fernando A. Jové,b Eric Sirianni,b Glenn P. A. Yap,b Klaus Theopold,b aSchool of Chemistry, The University of Manchester, Manchester (UK). bDepartment of Chemistry and Biochemistry, University of Delaware, Newark (USA). E-mail: stephen.sproules@ manchester.ac.uk Low-valent iron complexes are of interest for the activation of ubiquitous molecules such as N2 and O2. Iron containing oxygenases are among the most widespread and avidly studied enzymes, and both the biological and industrial fixation of nitrogen depend on this most abundant element. Utilising a sterically hindered ancillary Tp′ ligand (Tp′ = hydrotris(3-tert-butyl-5-methylpyrazol-1-yl)borato), we have accessed a series of Tp′Fe(L) complexes that bear a high-spin Fe(II) ion (S = 2) when L = Cl, Et; or a high-spin Fe(I) ion (S = 3/2) for L = CO, C2H4, N2. Interestingly, the latter exists as an equilibrium between the monomeric Tp′Fe(N2) and dinulear [Tp′Fe]2(μ-N2) forms. The dimer has been crystallographically and spectropscopically characterized with an S = 3 ground state that arises from the antiferromagnetic coupling between two high-spin Fe(II) ions (S = 2) bridged by the rarely encountered triplet N22‒ ligand (S = 1). Only five complexes of this type have been reported. Keywords: iron, dinitrogen, spectroscopy

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It has already been established that assembly of pentagonal units can lead to the formation of pseudo-spherical species.[1] In the same manner, it is impossible to build an extended two dimensional network with both three-fold and four-fold axes since they cannot be in the same plane. If both four-fold and three-fold axes are mixed together and held with an angle of approximately 55° to each other, a cluster with cubic symmetry should be obtained.[2] An octahedral hard metal centre coordinated to three acetylacetonato (acac) ligand generates a three-fold axis. By adding a methylpyridine (mpy) moiety to the acac unit, a second coordination site is generated. Addition of a square planar metal center, which generates the four-fold axis, to the [Al(acacmpy)3] brick should lead to a discrete octahedral cage. Copper(II) and cobalt(II) thiocyanate were used as square planar units. Reaction of [Al(acacmpy)3] with Co(NCS)2 gives a coordination network where it acts as a three-fold node. With Cu(II) in solution, there is evidence for a [Cu6{Al(acacmpy)3}8]12+ species.

Poster Sessions MS.C3.P.499 Nickel(II) and Copper(II) Complexes with 1,3-pndta and 1,3-pnd3a Ligands Ivana M. Stanojević,a Dušanka D. Radanović,b Urszula Rychlewska,c Beata Warżajtis,c Nenad S. Drašković,a Miloš I. Djuran,a aDepartment of Chemistry, Faculty of Science, University of Kragujevac, R. Domanovića 12, 34000 Kragujevac, (Serbia). bDepartment of Chemistry, Institute of Chemistry, Technology and Metallurgy, University of Belgrade, Njegoševa 12, P.O. Box 815, 11001 Belgrade, (Serbia). cFaculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, (Poland). E-mail: [email protected] The mixture containing (±)-1,3-pentanediamine-N,N,N’,N’tetraacetate (1,3-pndta) and its derivative (±)-1,3-pentanediamineN,N,N’-triacetate (1,3-pnd3a) ligands have been used for syntheses of the corresponding Ni(II) and Cu(II) complexes. Four complexes, two hexadentate, Mg[Ni(1,3-pndta)]⋅10H2O and Mg[Cu(1,3-pndta)].7H2O, and two pentadentate, Mg[Ni2(1,3-pnd3a)2].8H2O and Mg[Cu2(1,3pnd3a)2].7H2O, have been characterized using infrared and electronic absorption spectroscopic methods. The spectroscopic data for these complexes are compared with those of the analogous complexes with 1,3-pdta and 1,3-pd3a ligands, i.e. Mg[Ni(1,3-pdta)].8H2O, Mg[Cu(1,3-pdta)].8H2O and Mg[Cu2(1,3-pd3a)2].7H2O, of known crystal structures [1-3]. The crystal structure of [Mg(H2O)6][Ni(1,3pndta)]⋅4H2O complex has been established by X-ray analysis.



1,3-pndta

1,3-pnd3a

[1] U. Rychlewska, D.D. Radanović, V.S. Jevtović, D.J. Radanović, Polyhedron, 2000, 19, 1–5. [2] D.J. Radanović, T. Ama, H. Kawaguchi, N.S. Drašković, D.M. Ristanović, S. Janićijević, Bull. Chem. Soc. Jpn., 2001, 74, 701–706. [3] Z.D. Matović, A. Meetsma, V.D. Miletić, P.J. van Koningsbruggen, Inorg. Chim. Acta, 2007, 360, 2420-2431.

the limiting of coordination with this ligand family, by means of steric bulk influence and chelation preference research, in the hopes of finding separative properties in organometallic complexes of these metals. In the present investigation of these complexes, structural characterisation by means of single crystal X-ray diffraction, NMR spectroscopy and UV/Vis spectrophotometry will be discussed. The study of zirconium-metal complexes prepared with a range if N- and Odonating Ox-type ligands (see Fig 1) will be summarized, highlighting the more significant trends observed for this range of similar ligands.

Fig 1: Representation of a typical [Zr(ox)4] type complex, showing (a) general illustration of tetrakis coordinated zirconium metal centre; (b) fan-like arrangement of ligand planes. [1] R.C. Weast; CRC Handbook of Chemistry and Physics, 63rd Ed., 1982, The Chemical Rubber Publishing Company, USA. [2] I.V. Vinarov, Russ. Chem. Rev., 1967, 36, 522 - 536. [3] M. Steyn, A. Roodt, G. Steyl, Acta Cryst., 2008, E64, m827. [4] J.A. Viljoen, A. Roodt, H.G. Visser, M. Steyn, Acta Cryst., 2009, E66, m1367-1368. [5] J.A. Viljoen, A. Roodt, H.G. Visser, M. Steyn; Acta Cryst., 2009, E66, m1514-1515.

Keywords: zirconium, hafnium, oxyquinoline

MS.C3.P.501 Keywords: 1,3-pndta, nickel(II), copper(II)

MS.C3.P.500 Comparative Evaluation of Oxine-type Ligand Coordination at Zirconium(IV) Maryke Steyn, Andreas Roodt, Hendrik G. Visser, Department of Chemistry, University of the Free State, (South Africa). E-mail: [email protected] Zirconium and hafnium show extremely similar chemical properties and occur together in nature, and zircon, a zirconium silicate mineral (ZrSiO4), is the primary source of all hafnium. Zirconium and hafnium are contained in zircon at a ratio of about 50 to 1, [1] and the separation of these metals is very difficult due to the similarities in chemical behaviour [2]. This research project is aimed at studying the modes and preference for chelation of zirconium(IV) with regard to N- and O- donating multidentate ligands, since we found that zirconium and hafnium metal centres prefers a tetrakis coordination with bidentate ligands of the same family, in the solid state [3-5]. Furthermore, our investigation centres around the quinolinato (8-hydroxyquinoline; OxH) family of ligands, since we found these ligands to be ideal candidates for complex synthesis. This ligand family allows for room-temperature, bench-top synthesis methods, which allows for the application of simple UV/Vis Spectrophotometric kinetic studies. We proposed therefore to attempt

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Different Complexation Behaviour of PCXCP Ligands Towards Platinum Group Metals Marc Stickel,a Lars Wesemann,a Caecilia Maichle-Mössmer,a Hermann A. Mayer,a aInstitute of Inorganic Chemistry, University of Tübingen, Tübingen, (Germany). E-mail: [email protected] Complexes of Rh(I), Ir(I), Pd(II) and Pt(II) bearing X(CH2PR2)2 (X=NPh, S; R=Ph, tBu, Cy) [1-4] were synthesized. The nitrogen containing ligands (X=NPh) are always chelating and bidentate coordinating via the phosphine functions while the nitrogen stays uncoordinated. PhN(CH2PR2)2 (R=tBu, Cy) forms asymmetric monometallic complexes with mutually cis positioned carbonyl and chloro ligands coordinated to Rh(I) and Ir(I), respectively while symmetric complexes with two chelating ligands are formed with PhN(CH2PPh2)2. Reaction of X(CH2PR2)2 (X=NPh, S; R=Ph, tBu, Cy) with cycloocta-1,5-diene complexes [CODMX2] respectively bis(benzonitrile) complexes gives mononuclear cis palladium(II) and platinum(II) complexes [MX2L] (M=Pd, Pt; X=Cl, Br, L=ligand). The end on halides can easily be replaced by cyanide ions giving the monometallic cis dicyano complexes as shown for [M(CN)2{PhN(CH2PPh2)2}] (M=Pd, Pt). When the sulfur containing ligand S{CH2(PtBu)2}2 is reacted with IrCl(CO)2(p-toluidine) a twelve membered diiridamacrocyclus is formed by coordination of the phosphine groups to Ir(I). [1] Maier, L., Helv. Chim. Acta, 1965, 48, 1034. [2] Balch, A. L.; Olmstead, M. M.; Rowley, S. P., Inorg. Chim. Acta, 1990, 168, 255. [3] Klemps, C.; Payet,

Poster Sessions

Keywords: PCXCP, platinum group, complexation behavior

MS.C3.P.502 Properties of γ-substituted β-diketone-containing Rh complexes NF (Mpondi) Stuurman-Molefea, JeanetConradie,a aDepartment of Chemistry, University of the Free State, Bloemfontein 9300, South Africa. E-mail: [email protected] β-Diketone complexes of transition metals have been extensively studied by both homogeneous and heterogeneous catalytic chemists [1]. The catalytic reactivity of these complexes (Rhodium in particular) is in many respects due to the nature of ligand surroundings [2] and is determined largely by the relative frontier orbital energies [3]. Electron density of the rhodium(I) centre is removed if there is a more electronegative ligand attached to the rhodium complex, causing the complex to be a stronger Lewis acid and less reactive towards oxidative addition, thus a weaker electrophile [4]. The β-diketone group incorporates a strong dipole moment which increases the anisotropy of the molecular polarizability and consequently favours mesogenic behaviour [5]. Mesogenic behaviour can sometimes be further enhanced when β-diketones are coordinated to metals [6]. A terminal polar group is for example provided by [M(CO)2] or [RhCl(CO)2] while on the other hand the decyloxy group attached at the gamma position of the β-diketonates play the role of an electron-donor group, this also enhances mesomorphism [7]. A series of γ-substituted β-diketones and their carbonyl complexes of rhodium(I) has been synthesized and characterized by Infra-Red, Nuclear Magnetic Resonance, electrochemistry (Cyclic Voltammetry, linear sweep voltammetry and Qsteryoung Square wave voltammetry) and computational calculations (Density Functional Theory). The potential mesophase properties of the ligands are investigated by using a Polarizing Optical Microscope (POM) and Differential Scanning Calorimetry (DSC). Results show that both the gamma substituted and the β-diketonato backbone is redox active. Some of the ligands exhibit more than one meso liquid phase.

[1] W.R. Cullen, E.B. Wickenheiser, J. Organomet. Chem., 1989, 370, 141. [2] E.A. Shor, A.M. Shor, V.A. Nasluzov, A.I. Rubaylo, J. Struct. Chem., 2005, 46, 220; L. Cavallo, M. Sola, J. Am. Chem. Soc., 2001, 123, 12294. [3] I. Fleming, Frontier Orbitals and Organic Chemical Reactions, Wiley, New York, 1976; K. Fukui, Top. Curr. Chem. 1970, 15, 1. [4] S.S. Basson, J.G. Leipoldt, J.T. Nel, Inorg. Chim. Acta., 1984, 84, 167; W.H. Thompos, C.T. Sears, Inorg. Chem., 1977, 16, 769; A.J. Hart-Davis, W.A.G. Graham, Inorg. Chem., 1970, 9, 2658. [5] G.W. Gray, P.A. Winsor, Liquid Crystals & Plastic Crystals; Ellis Horwood Limited: Chichester, U.K., 1974, Vol. 1, Chapter 4. [6] D.W. Bruce, J. Chem. Soc., Dalton Trans. 1993, 2984; P. Espinet, M.A. Esteruelas, L.A. Oro, J.L. Serrano, E. Sola, Coord. Chem. Rev. 1992, 117, 215 [7] J. Barbera´, A. Elduque, R. Gime´nez, F.J. Lahoz, J.A. Lo´pez, L.A. Oro, J.L. Serrano, B. Villacampa, J. Villalba. Inorg. Chem., 1999, 38, 13.

MS.C3.P.503 Synthesis and Properties of Oxo-carboxylato- and Dioxo-bridged Diosmium Complexes of Tris(2-pyridylmethyl)amine Hideki Sugimoto,a Kazuhiro Kitayama,a Kenji Ashikari, Shinobu Itoha a Department of Materials and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Science, Osaka University (Japan). E-mail: [email protected] The present paper reports synthesis and characterization of oxobridged diosmium complexes of nitrogen-based tetradentate ligand (tpa).[1] They cover m-oxo-m-carboxylate-diosmium(III) complexes, [OsIII2(m-O)(m-RCOO)(tpa)2]3+ (R = C3H7, CH3, and C6H5) and -osmium(III)osmium(IV) complex, [OsIIIOsIV(m-O)(m-C3H7COO) (tpa)2]4+ as well as di-m-oxo-osmium(III)osmium(IV) complex, [OsIIIOsIV2(m-O)2(tpa)2]3+. The complexes with bridging carboxylate are the first examples of the m-oxo-m-carboxylato-diosmium complexes. The doubly oxo-bridged complex is also the first example of mixed-valent di-m-oxo-diosmium complex. The series of m-oxom-carboxylato-dimetal complexes has now been completed for group 8 elements of Fe, Ru, and Os. The complex of [OsIIIOsIV(m-O) (m-C3H7COO)(tpa)2]4+ added a new member of oxidation number in the series. Among the series, the diruthenium and diosmium complexes exhibit a low spin state. X-ray structural study reveals increasing dp-pp interaction in the diosmium complex as evident from the increase in the M-O-M angle. From the redox potentials, higher oxidation states are increasingly stabilized in the diosmium complex. The pH-dependent cyclic voltammogram of the butylate complex indicated that the proton-coupled two-electron transfer is involved in the reduction of [OsIII2(m-O)(m-C3H7COO)(tpa)2]3+ to yield hydroxobridged diosmium(II) compound, [OsII2(m-OH)(m-C3H7COO)(tpa)2]2+. The significantly shorter osmium(III)-osmium(IV) bond distance than the sum of radii of two osmium atoms indicates the presence of a direct Os-Os bond. The existence of the order of 1.5 is suggested for the direct Os-Os bond of the di-m-oxo complex, by comparing the metalmetal distance with the isostructural rhenium(III)rhenium(IV) and dirhenium(IV) complexes.[2]

[1] H. Sugimoto, K. Kitayama, K. Ashikari, C. Matsunami, N. Ueda, K. Umakoshi, Y. Hosokoshi, Y. Sasaki, S. Itoh, Inorg. Chem., 2011, 50, 90149023. [2] H. Sugimoto, M. Kamei, K. Umakoshi, Y. Sasaki, M. Suzuki, Inorg. Chem., 1996, 35, 7082-7088.

Keywords: dinuclear complex, osmium, metal-metal interaction

MS.C3.P.504 Chiral Tetradecanuclear Nickel(II) Cage Complex with Imidazole Containing Ligand Yukinari Sunatsuki,a Azusa Yokoi,a Takayoshi Suzuki,a Akira Fuyuhiro,b Masaaki Kojima,a aGraduate School of Natural Science and Technology, Okayama University, Okayama, (Japan). b Graduate School of Science, Osaka University, Toyonaka, (Japan). E-mail: [email protected]

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E.; Magna, L.; Saussine, L.; Le Goff, X. F.; Le Floch, P., Chem. Eur. J., 2009, 15, 8259. [4] Hiraki, K.; Khono, S.; Ondi, M.; Kuwahara, T.; Miohita, Y., Inorg. Chim. Acta, 1996, 245, 243.

Poster Sessions Molecular cages are of great interest in the property and reactivity of included molecule in their inner space shielded from an outer environment.[1] We have designed the imidazole containing ligand, HLOH, as shown in Fig. 1 in order to prepare cluster complexes. The reaction of HLOH and Ni(ClO4)2·6H2O under basic condition gave yellowish brown crystals of [{Ni(LOH)3}8Ni6](ClO4)4·4H2O·4MeOH (1). X-ray crystallographic study revealed that this complex has a tetradecanuclear cubic cage structure including the spherical inner space with ca. 7.7 Å diameter as shown in Fig. 2. This cage is constructed by eight [Ni(LOH)3]‒ units on the corners of the cube, having octahedral coordination geometry, and six square planar Ni(II) on the center of the each face, coordinated by four imidazolate nitrogen atoms from respective [Ni(LOH)3]‒ units. An alcoholic oxygen atom of ligand did not coordinate to Ni(II) ion. In the crystal, there is at least one water molecule and no perchlorate anion in the inner space. Complex 1 crystallizes in the non-centrosymmetric space group P432 and spontaneous resolution occurs. All eight [Ni(LOH)3]‒ units of the cage have the same chirality, thus, the cage, [{Ni(LOH)3}8Ni6]4+, is also chiral. Under existence of excess hexamethylenetetramine (hmt), the corresponding reaction for 1 gave the hmt including cage, {[{Ni(LOH)3}8Ni6]⊃hmt}(ClO4)4·10H2O (1⊃hmt). 1⊃hmt is isomorphous to 1 and the hmt molecule is in the cage. It is expected that the chiral recognition and the chiral separation are achieved using the present chiral cage. The study is in progress along this line.

The synthesis, properties and structures of a series of cobalt complexes which show fully reversible O2 chemisorption with near stoichiometric uptake in the solid state will be described. Interestingly these compounds are non-porous in their deoxy forms. Uptake is highly selective, consistent with a chemisorptive process. The ambient temperature (25°C) adsorption of O2, CO2, N2 and Ar into [{Co2(bpbp)}2bdc](PF6)4 (bpbp = 2,6-bis(N,N-bis(2-pyridylmethyl) aminomethyl)-4-tert-butylphenolato, bdc = 1,4-benzenedicarboxylato) is shown below.[2] With this material we have acheived a selectivity of O2 binding over N2 10 times the current state-of-the-art in physisorptive zeolite technology.[3] Recently a new derivative which undergoes single-crystal-tosingle-crystal desorption of oxygen has provided invaluable insight into the mechanism of chemisorption.

Gas sorption isotherms for O2 (red l), CO2 (black), N2 (blue t) and Ar (green n) on [{Co2(bpbp)}2bdc](PF6)4 at 25 °C. Unfilled data points were measured during desorption after a maximum pressure of 10 bar. Inset: Expansion of the low pressure region. [1] J-R Li, R. J Kuppler, H-C Zhou, Chem. Soc. Rev., 2009, 38, 1477-1504. [2] P. D. Southon, D. J. Price, P. K. Nielsen, C. J. McKenzie and C. J. Kepert, J. Amer. Chem. Soc., 2011, 133, 10885-10891. [3] S. Sircar, M. B. Rao, T. C. Golden, In Adsorption and Its Applications in Industry and Environmental Protection, Vol. I: Applications in Industry, Elsevier Science Publ B V: Amsterdam, 1999, 120, 395.

Fig. 1 HLOH (right) and one of its deprotonated form, (LOH)‒ (left).

Fig. 2 The ORTEP drawing of 1. The counter anions and crystal solvents were omitted for clarity.

[1] M. Yokokawa, J. K. Klosterman, M. Fujita, Angew. Chem. Int. Ed., 2009, 48, 3418‒3438.

Keywords: cage complex, molecular structure, chirality

MS.C3.P.505 Reversible Chemisorption of Oxygen Into Non-Porous Solids Jonas Sundberg,a Lisa J. Cameron,b Peter D. Southon,b Cameron J. Kepert,b Christine J. McKenzie,a aDepartment of Physics, Chemistry & Pharmacy, University of Southern Denmark, Odense, (Denmark). b School of Chemistry, University of Sydney, Sydney (Australia). E-mail: [email protected]. Materials which can be easily recycled at near ambient temperatures are sought for chemisorption of oxygen.[1] Potential applications include oxidation catalysts, sensors, storage and separation of oxygen for medical and industrial uses. An efficient system needs to exhibit both high capacity, and selectivity over other gases such as nitrogen and carbon dioxide.

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Keywords: single-crystal-to-single-crystal, chemisorption, solidstate

MS.C3.P.506 Stereochemistry of Quinolinophaneoxazoline (h6-p-Cymene) Ru(II) Complexes by ECD Studies Stefano Superchi,a Renzo Ruzziconi,b Riccardo Zanasi,c Gianfranco Bellachioma,b Gianluca Ciancaleoni,b Guglielmo Monaco,c a Dipartimento di Chimica, Università della Basilicata, Potenza (Italy). b Dipartimento di Chimica, Università di Perugia, Perugia (Italy). c Dipartimento di Chimica e Biologia, Università di Salerno, Fisciano (SA),(Italy). E-mail: [email protected] Chiral bidentate N,N-ligands are known to provide efficient catalysts for asymmetric synthesis. To this end, C2-symmetric ligands have been intensively exploited, while much less attention have been devoted to N,N-ligands exhibiting different types of chirality. Looking for new efficient chiral catalysts for stereoselective transformations we decided to investigate a new class of bidentate N,N-ligands displaying both planar and central chirality, bearing both quinolinophane and oxazoline chiral N-donor moieties. Optically pure 4-substituted-{[2] paracyclo[2](5,8) quinolinophan-2-yl}oxazolines 1-5 were then synthesized and used to prepare the corresponding ruthenium(II) arene

Poster Sessions chloro complexes 6-10 (Figure). Complexation of ligands 1-5 with Ru(II) generates a new stereogenic center at the metal. Therefore, in principle, any ligand could give rise to a couple of diastereoisomers having opposite absolute configuration at ruthenium. With much to our delight we found that a sole Ru(II) complex was obtained from each ligand, showing that the ligand chiral moieties exert a strong influence in determining the relative position of chlorine and h6-p-cymene around metal. A full stereochemical characterization of complexes 6-10 was undertook by experimental and computational analysis of their electronic circular dichroism (ECD) spectra, with the aim to determine the unknown absolute configuration at metal. ECD spectra appeared mainly dominated by transitions allied to the chiral metal center. Moreover, from spectral analysis it was possible to establish that metal absolute configuration was determined only by the chirality of the paracyclo-quinolinophane moiety. The stereogenic center on the oxazoline moiety apparently does not exert any effect on the Ru configurational preference. Comparison of ECD spectra of complexes 6-10 with those obtained by TD-DFT computational simulation[1] at B3LYP/SVP level also allowed to establish SM absolute configuration at the ruthenium atom for complexes 6b-10 having Rp configuration at the quinolinophane moiety.

solution was stood for several days under air at room temperature until reddish brown crystals appeared. The crystals were collected, washed by water, ethanol and ether, and dried. The source of O2- is considered to be H2O, mixed in an acetone solution. X-ray structural analysis revealed that this complex has one oxo ligand (O2-) bridged between two ruthenium centers and two chlorido and ebpma ligands coordinated to each ruthenium center (Figure 1). Cyclic voltammograms in acetonitrile at room temperature showed two reversible redox waves at -0.46 (W1) and 0.74 V (W2) and one irreversible reduction wave at -1.37 V (W3) (Figure 2). UV-Vis spectra of the complex in acetonitrile showed an absorption band at 460 nm.

Figure 1. ORTEP of the oxo-bridged dinuclear ruthenium complex

[1] J. Autschbach, L. Nitsch-Velasquez, M. Rudolph, Top. Curr. Chem. 2011, 298, 1-98.

MS.C3.P.507 Synthesis and Characterization of an Oxo-bridged Diruthenium Complex Tomoyo Suzuki, Akari Kajihara, Kazuhiro Matsuya, Sohei Fukui, Hirotaka Nagao, Department of Materials and Life Sciences, Sophia University (Japan). E-mail: [email protected] Syntheses and ligand substitution reactions of mixed-valence dinuclear ruthenium (II,III) complexes, triply bridged by halogeno (X-) and alkoxo (RO-) ligands, bearing ethylbis(2-pyridylmethyl)amine (ebpma) as a flexible tridentate supporting ligand, [{RuII,III(ebpma)}2(m-X)3-n(m-OR)n]2+ (n = 0-2) have been investigated [1]. The triply chlorido-bridged diruthenium (III,II) complex was reduced by zinc to afford an isovalent dinuclear ruthenium (II,II) complex, [{RuII,II(ebpma)}2(m-Cl)3]PF6. In this work, an isovalent dinuclear ruthenium complex, singly bridged -by an oxo ligand (O2-), was synthesized and characterized. The oxo-bridged diruthenium complex was synthesized from the reaction of the [{RuII,II(ebpma)}2(m-Cl)3]PF6 in an acetone-H2O mixed solution containing a chloride ion source such as KCl or HCl. The

Figure 2. CVs in acetonitrile containing TEAP as electrolyte [1] K. Matsuya, S. Fukui, Y. Hoshino, and H. Nagao, Dalton Trans., 7876(2009).

Keywords: ruthenium, dinuclear, oxo-bridged

MS.C3.P.508 Mononuclear and Dinuclear RhIII and IrIII Complexes Bearing 5-Methyltetrazolate Takayoshi Suzuki, Asuka Takayama, Miyu Ikeda, Yukinari Sunatsuki, Masaaki Kojima, Graduate School of Natural Science and Technology, Okayama University, Okayama (Japan). E-mail: suzuki@okayama-u. ac.jp Tetrazolates (RCN4–) are versatile ligands for design and construction of functional di- or polynuclear metal complexes. Since RCN4– has four successive N atoms, all of which can coordinate to a metal center, in a five-membered aromatic ring, the mono- and dinuclear metal complexes afford two linkage (-kN1 and -kN2) and four bridging (m-kN1:kN2, m-kN1:kN3, m-kN1:kN4 and m-kN2:kN3) isomers, respectively. In our previous study with 5-methyltetra-zolate (R = Me) and “Cp*IrIII(L–L)” fragments, where L–L was 2,2’-bipyridine (bpy), N,N-dimethyldithiocarbamate (Me2dtc–) or 2-pyridinethiolate (2-Spy–),

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Keywords: Ruthenium complexes, electronic circular dichroism, paracyclophanes

Poster Sessions it was revealed that the coordination or bridging modes of MeCN4– were dependent on the auxiliary (L–L) ligands. In this study, we have extended the MeCN4– coor-dination chemistry to the heterodimetallic system using Cp*RhIII and Cp*IrIII moieties. Also, 2-(2-pyridyl)phenyl (ppy–) was utilized as a new auxiliary ligand. At first, mononuclear complexes of [Cp*M(ppy)(MeCN4)] {M = Ir (1) or Rh (2)} were prepared, and their crystal structures were determined by X-ray. Interestingly, these complexes in the crystals were the MeCN4-kN1 isomers (Figure 1a), in contrast to the bpy analogs of [Cp*M(bpy)(MeCN4-kN2)]PF6 {M = Ir (3) or Rh (4)}. The C–H/p interaction between the methyl group of MeCN4– and the phenyl ring of ppy– may contribute to the stability of the kN1 isomer of ppy complexes. Further, the Ir complex 1 was robust in solution; however, the Rh complex 2 exhibited linkage isomerization in CDCl3 (see: Figure 1b). Heterodinuclear complexes bridged by MeCN4– were prepared by a reaction of mononuclear IrIII complex (1 or 3) and “Cp*RhIII(L–L)” fragment that was prepared in situ from the corresponding chloride complex and AgPF6 in methanol. Among several dinuclear complexes prepared in this study, [Cp*Rh(ppy){m-MeCN4kN1(Rh):kN3(Ir)}Ir(bpy)Cp*](PF6)2 (5) and its metal-position (coordination) isomer, [Cp*Ir(ppy){m-MeCN4-kN1(Ir):kN3(Rh)}Rh-(bpy) Cp*](PF6)2 (6) showed an interesting phenomenon. These complexes in solution exhibited an isomerization equilibrium between the m-kN1(M1):kN3(M2) and m-kN1(M2):kN3(M1) bridging isomers, as well as the dissociation equilibrium of the “Cp*Rh(L–L)” fragment. However, on crystallization from the equilibrium mixture, the crystals of a specific isomer of 5 or 6 were selectively formed.

drastically decreases from the π* energy levels of tpy ligand upon protonation. Both [1]+ and [1a]+ show catalytic water oxidation ability in chemical and electrochemical methods. The catalytic activities of cisisomer [1a]+ is lower than the trans-isomer [1]+ with respective TON values 1200 and 3500. The higher catalytic activity of trans-isomer than the cis-isomer, is expected due to the lower pKa2 value compared to the cis-isomer and the contribution by trans-effect of the carbon coordination. To the best of our knowledge, it is the first example of a mononuclear cyclometalated ruthenium complex that behaves as a water oxidation catalyst (WOC) in electrochemical method. We will discuss the mechanistic for water oxidation in both the methods.

[1] S. K. Padhi, K. Kobayashi, S. Masuno, K. Tanaka, Inorg. Chem. 2011, 50, 5321-5323.

Keywords: Photo isomerization, Water oxidation, Proton coupled electron transfer

MS.C3.P.510

Figure 1. (a) ORTEP of [Cp*Rh(ppy)(MeCN4-kN1)] (2) (hydrogen atoms omitted) and (b) 1H NMR spectrum of a CDCl3 solution of 2. [1] M. Kotera Y. Sekioka, T. Suzuki, Inorg. Chem., 2008, 47, 3498–3508.

Keywords: linkage isomerism, 2-(2-pyridyl)phenyl, selective crystallization

MS.C3.P.509 Photo-isomerization and Water Oxidation by Mononuclear Ruthenium Complexes Koji Tanaka,a,b Sumanta Kumar Padhi,b Ryoichi Fukuda, b Masahiro Ehara,b aInstitute for Integrated Cell-Material Sciences, Kyoto University, Funai Center#201, Kyoto University Katsura, Nishikyoku, Kyoto, (Japan). bInstitute for Molecular Science, 38 Nishigo-Naka, Myodaiji, Okazaki, (Japan). E-mail: [email protected] Visible-light (λ≥420 nm) irradiation to cyclometalated trans[Ru(tpy)(PAD)(OH2)]+ [1]+ (tpy = 2,2’;6’,2”-terpyridine, PAD = 2-(pyrid-2’-yl)-acridine) causes isomerization to form cis-[Ru(tpy) (PAD)(OH2)]+ [1a]+. Protonation of non-bonded nitrogen in PAD brings about electron flow from the central Ru to PAD, which induces a tautomeric equilibrium between Ru–C and Ru=C coordination modes. [1] This is in agreement with the theoretically predicted geometries and the experimental UV-vis results. The LUMO energy levels of PAD

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Synthesis of Platinum(II) Complexes with Benzothiazole Derivatives as Photosensitizing Agents Yukino Taniguchi, Yuhei Miyazaki, Tatsuya Kawamoto, Department of Chemistry, Kanagawa University, Hiratsuka, (Japan). E-mail: [email protected] It is well known that 2-substituted benzothiazoles are a considerably important class of compounds due to their broad biological and pharmaceutical properties [1]. On the other hand, cyclometalated platinum(II) complexes have attracted much attention as organic lightemitting devices [2] and luminescent oxygen sensors [3]. Here we report synthesis of cyclometalated platinum(II) complexes containing benzothiazole derivatives as ligands and their photosensitizing ability for visible light-driven hydrogen production reaction from water in the multi-component systems comprised of a water reduction catalyst, a sacrificial reductant, and an electron relay.

[1] C. S. Lim, G. Masanta, H. J. Kim, J. H. Han, H. M. Kim, B. R. Cho, J. Am. Chem. Soc., 2011, 133, 11132-11135. [2] A. Y. Y. Tam, D. P. K. Tsang, M. Y. Chan, N. Zhu, V. W. W. Yam, Chem. Commun., 2011, 47, 3383-3385. [3] W. Wu, W. Wu, S. Ji, H. Guo, J. Zhao, Dalton Trans., 2011, 40, 5953-5963.

Keywords: benzothiazoles, cyclometalated platinum complex, photosensitizer

Poster Sessions MS.C3.P.511 Activation Mechanism of Peroxides by Copper Complexes Tetsuro Tano, Hideki Sugimoto, Nobutaka Fujieda, and Shinobu Itoh. Department of Material and Life Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871 (Japan). E-mail: [email protected] Alkylperoxo complexes of non-heme transition-metal ions (M– OOR) have attracted much attention due to their strong relevance to biological and catalytic oxidation reactions. However, little is known about the intrinsic reactivity of copper-alkylperoxo complexes, even though the complexes have been invoked as a key reactive intermediate in several biological and catalytic oxidation and/or oxygenation reactions. We have recently reported the synthesis and reactivity of mononuclear copper(II)-cumylperoxo complexes supported by a pyridylmethylamine tridentate ligand (bmpa, Chart 1).[1] The cumylperoxo copper(II) complex was found to undergo homolytic O-O bond cleavage concomitant with the C-H bond abstraction of exogenous substrates. In this study, we have examined the reactivity of copper(I) complexes supported by similar ligands toward various peroxides in order to get insight into the O–O bond breaking pattern of the Cu(I)-alkylperoxo complexes.

Figure 1. UV-vis spectra of 3 and 4 in CH3CN at –40oC. [1] T. Tano et al., Dalton Trans., 2012, 40, 10326-10336.

Keywords: Copper Complex, Peroxides, O-O Bond Breaking Pattern

MS.C3.P.512

The complex Alq3 (Hq = 8-hydroxyquinoline) has been extensively studied as a solid state component in muti-layer thin-film OLED devices in which Alq3 is found as an amorphous mixture of the merand fac-isomers. The mer-isomer has also been comprehensively studied in solution but the instability of the fac form in solution has precluded the same degree of research into this important component of OLEDs. By designing a hydroxyquinoline-based ligand incorporating a thiol-alkyl chain, it has been possible to force the formation of the fac isomer of an Alq3 derivative in solution via the addition of soft metal ions such as Ag+ and Cd2+. The presence of a long alkyl chain gives rise to the possibility of liquid crystalline properties[1].

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A mononuclear copper(I) complex 1 supported by bmpa (Chart 1) and a dinuclear copper(I) complex 2 supported by the dinucleating ligand with two pyridylmethylamine tridentate donor units (bmpa2, Chart 1) have been synthesized and their reactivity toward cumene hydroperoxide (CmOOH) have been examined in detail using lowtemperature UV-vis and ESI-MS. The reaction of these copper(I) complexes, 1 and 2, reacted with CmOOH in acetonitrile at –40℃ in 2: 1 ratio to give intermediate 3 and 4 having an intense LMCT band at 388 nm and 363 nm, respectively. Quantitative analysis of decomposition products generated from the cumylperoxo complexes demonstrated that the copper(I)-cumylperoxo complexes undergo heterolytic cleavage of the O–O bond of the cumylperoxo moiety, which is in sharp contrast to the self-decomposition reaction of copper(II)-cumylperoxo complexes involving homolytic cleavage of the O-O bond [1]. Ligand effects on the structure and reactivity of the generated intermediates 3 and 4 are discussed.

Isomerisation of an Alq3 Derivative in Solution by Addition of Soft Metal Ions Nicholas Tart,a Jean-François Lemonnier,a Emmanuel Terazzi,a Daniel Emery,b Jiri Mareda,b Laure Guénée,c Claude Piguet.a aDepartment of Inorganic, Analytic and Applied Chemistry, University of Geneva, Switzerland. bDepartment of Organic Chemistry, University of Geneva. c Crystallography Laboratory, University of Geneva. E-mail: Nicholas. [email protected]

Poster Sessions

Scheme 1 [1] F. Pérez-García, A. R. Tapia-Benavides, H. Tlahuext, A. Alvarez, M. Tlahuextl, Struct. Chem., 2006, 17, 359-366. [2] T. G. Carter, W. J. Vickaryous, V. M. Cangelosi, D. W. Johnson, Comments Inorg. Chem., 2007, 28, 97-122. [3] A. Chandrasekaran, P. Sood, R. O. Day, R. H. Holmes. Inorg. Chem., 1999, 38, 3369-3376.

Keywords: Spiroarsoranes, Spirophosphoranes, NBO

MS.C3.P.514 [1] E. Terazzi, L. Guénée, J. Varin, B. Bocquet, J.-F. Lemonnier, D. Emery, C. Piguet, Chem. Eur. J., 2011, 17, 184-195.

Keywords: hydroxyquinaldine, aluminium complex, isomerisation

MS.C3.P.513 P-O and As-O Dative Bonds in Spirocompounds Derivates From 2-Aminophenol Margarita Tlahuextl,a Martha Falcón-León,a Hugo Tlahuext,b Rafael Tapia-Benavides,a aCentro de Investigaciones Químicas, Universidad del Estado de Hidalgo, Hidalgo, (México). bCentro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos, Morelos (México). E-mail: [email protected] Phosphoranes are labil compounds in solvents that contain oxygen atoms because of great avidity of phosphorus toward oxygen. In aqueous solutions, the water-phosphorus interactions yield a chemical equilibrium between tetra- and pentacoordinated species. On the other hand, arsoranes are thermodynamically stable compounds in the presence of water and it is not likely that they undergo intermolecular exchange. Arsenic has the ability to mimic phosphorus and it is involved in different metabolic processes. Phosphates and phosphoranes are the centrepiece of biochemical reactions whereas arsenic compounds are generally toxic. It has been reported that phosphorus and arsenic compounds have the possibility to form P-O and As-O dative bonds [1-3]. In these compounds, oxygen atoms send electronic density toward an empty “p” orbital of the pnicogen atom [n(O)→n*(Pn)]. Although, phosphoranes and arsoranes are very similar compounds, it is not still known how much different are P-O and As-O interactions. P-O bonds in phosphoranes are more sensitive to aqueous media than As-O bonds. In view of this lack of knowledge about P-O and As-O bond nature, we set out to determine the presence and differences of O→Pn dative bond character in phosphoranes and arsoranes derivates from 2-aminophenol. The dative character of O→Pn bonds was researched through the use of X substituent (X = H, F, Cl, Br) placed in equatorial position of spirocompounds 1 and 2. In this context, we decided to use NBO (Natural Bond Orbital) analysis to set up the dative character of O→Pn bonds. NBO computations were carried out in MP2/631+G(2d,2p) level.

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Syntheses and Characterization of Ru(II)-dmso Complexes with a Picolinate Ligand Mari Toyama, Nobuyoshi Tanaka, And Noriharu Nagao, School of Science and Technology, Meiji University, Kanagawa (Japan). E-mail: [email protected] Our previous work has showcased that selective synthesis and crystal structure of a mono(dpk)Ru(II) complex trans(Cl),cis(S)[RuCl2(dmso-S)2(dpk-k2N,O)] (dpk = di-2-pyridyl ketone), in which a dpk ligand binds to a Ru2+ ion through one pyridyl N and a carbonyl O atom (k2N,O-coordination mode).[1] The focus of this study is reaction of Ru(II)-dmso complex with Hpic to form a mono(pic)Ru(II) complex (pic = picolinate). The ligand pic acts as an anionic bidentate ligand to Ru2+ ion via a pyridyl N and a carboxylate O– (k2N,O–-coordination mode), as far as we know. The reaction between trans(Cl)-[RuCl2(dmso-S)4] and Hpic in H2OEtOH at room temperature afforded trans(Cl),cis(S)-[RuCl2(dmsoS)2(Hpic)] (1). Reaction of 1 with Ag+ afforded trans(Cl),cis(S)Ag[RuCl2(dmso-S)2(pic)] (Ag·2). Moreover, the dissolving of Ag·2 in DMSO afforded fac(S)-[RuCl(dmso-S)3- (pic)] (3), which has been also obtained from the reaction between cis(Cl),fac(S)-[RuCl2(dmsoS)3(dmso-O)] and Hpic with Et3N by Alessio and co-workers.[2] The ORTEP drawings of 1·H2O and 3 are shown in Figure 1. For 1, the Ru ion had a distorted octahedral geometry with two trans(Cl) atoms. The trans(Cl),cis(S)-configuration of two dmso and two Cl– ligands in 1 was same as that of the mono(dpk-k2N,O)Ru(II) complex. The C6-O1 distance (1.239(4) Å) is shorter than the C6-O2 distance (1.294(4) Å), and is comparable to the C-O distance (1.243(3) Å) in the carbonyl group of the dpk in the mono(dpk-k2N,O)Ru(II) complex. Therefore, the O1 atom is a carbonyl oxygen atom, so that, in 1 a pic ligand binds to Ru2+ ion through pyridyl N atom and a carbonyl O atom. It has been shown that 3 is able to crystallize in different forms, depending upon the crystallization condition. Alessio and co-workers obtained tetragonal crystals, P42/n,[2] while monoclinic, P21/n were obtained by us. The C6-O1 distance (1.296(14) Å) is longer than the C6-C2 distance (1.172(13) Å), that is, the C6-O1 bond is a single bond and the C6-O2 bond is a double bond. These crystal structures of 1 and 3 revealed that the pic ligand can has two kinds of coordination modes, the k2N,O- and the k2N,O–-coordination modes. The Ru-N distance in 1 (2.128(3) Å) is similar to that in 3 (2.128(9) Å), while the Ru-O distance in 1 (2.139(2) Å) is shorter than that in 3 (2.120(7) Å). 1 H NMR spectra of 1 and 2 in DMSO-d6 are identical. It is indicated that in DMSO solution the H+ of an Hpic in 1 is released to form trans(Cl),cis(S)-[RuCl2(dmso-S)2(pic)]–.

Poster Sessions

Figure 1. ORTEP drawings of 1·H2O (a) and 3 (b). Figure 1 The europium(III) complexes and the ligands

[1] M. Toyama, M. Nakahara, and N. Nagao, Bull. Chem. Soc. Jpn. 2007, 80, 937–950. [2] I. Bartsos, C. Simonin, E. Zangrando, T. Gianferrara, A. Bergamo, and E. Alessio, Dalton Trans. 2011, 40, 9533-9543.

Keywords: europium, Schiff base, photoluminescence

Keywords: ruthenium(II) complex, X-ray crystal structure, coordination mode

MS.C3.P.516

Luminescence Properties of Mononuclear Schiff BaseEuropium(III) Complexes Masanobu Tsuchimoto,a Narihiro Yoshida,b Shouta Ebato,b Masayuki Watanabe,c Kiyohiko Nakajima,d Department of Chemistry, Chiba Institute of Technology , (Japan). bDepartment of Life and Environmental Sciences, Chiba Institute of Technology, (Japan). c Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, (Japan). dDepartment of Chemistry, Aichi University of Education, (Japan). E-mail: [email protected] Photoluminescence is one of the distinctive properties of europium(III) complexes. A large number of luminescent europium(III) complexes were prepared, and their luminescent properties have been extensively investigated. Recently, we found out highly photoluminescent mononuclear europium(III) complexes with tetradentate Schiff base ligands, (C2H5)3NH[Eu(3,5Clsalen)2] (H23,5Clsalen: N,N’-bis-3,5-dichlorosalicylidene-1,2-ethanediamine). The complex has an eight-coordinated mononuclear structure with two Schiff base ligands in a meridional form. The triethylammonium cation is hydrogen bonded to the oxygen atom of the complex anion in crystals. The complex shows red luminescence based on f-f transitions by excitation with UV light in solutions and in the solid state. In this study, mononuclear europium(III) complexes with various salen-type Schiff base ligands, X[Eu(L)2] (X = Et3NH+, Et4N+; H2L=salen-type Schiff base ligands, Figure 1) were prepared, and their photoluminescence properties are compared. The triethylammonium salts of the europium(III) complexes were prepared by the reaction of europium(III) acetate with the Schiff base ligand (H2L) in methanol or in ethanol containing triethylamine. The tretraethylammonium salts of the europium(III) complexes were prepared by the reaction of europium(III) acetate with the Schiff base ligand in methanol containing pyridine and tetraethyammonium chloride. All the complexes are pale yellow, and show red luminescence based on f-f transitions by excitation with UV light. However, the emission intensities obtained by 365nm excitation are considerably different between the europium(III) complexes which contain different Schiff base ligands and counter cations. There is also a solvent dependence on the emission intensities of Et3NH[Eu(3,5Clsalen)2] in solutions. The factors affecting the emission intensity differences caused by changing the N—N framework of the diamine moieties, counter cations, and solvents are discussed.

Metalladithiolene complexes of late transition metals exhibit remarkable physical and chemical properties such as reversible redox activity, deep color, and various substitution and addition reactions. Their interesting properties are due to the quasi-aromaticity and electronic unsaturation of the metalladithiolene ring. The metalladithiolene rings can be used as building brocks for metal cluster complexes, and we have developed multinucleation methodologies of metalladithiolene complexes (Scheme 1a and b).[1, 2] In this study, we achieved the synthesis of neutral nonanuclear and hexanuclear dithiolene cluster complexes 4 and 6 using our multinucleation methodologies to p-conjugated trinuclear dithiolanes 3 and 5 (Scheme 1c and d).[3] 4 showed strong electronic communication in the mixed-valent states among the three [Co2(CO)5] units because of planar configuration and the resultant p-conjugated electronic structure (Figure 1a). In contrast, 6 displayed a far weaker interaction among the [Fe(CO)3] units due to the bent metalladithiolene rings and the accompanying disrupted p-conjugation (Figure 1b).

Scheme 1. Synthesis of multinuclear metalladithiolene cluster complexes.

Figure 1. Differential pulse voltammograms of 4 (a: in 0.1 M Bu4NClO4-PhCN) and 6 (b: in 0.1 M Bu4NClO4-PhCN/toluene (1:1 v/v)) at 0.1 Vs-1.

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MS.C3.P.515

Correlation between Structure and Electronic Communication of Metalladithiolenes Satoru Tsukada,a Yusuke Shibata,b Ryota Sakamoto,b Tetsuya Kambe,b Hiroshi Nishihara,b aDepartment of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science (Japan). bDepartment of Chemistry, Graduate School of Science, The University of Tokyo (Japan). E-mail: [email protected]

Poster Sessions [1] N. Nakagawa, T. Yamada, M. Sugimoto, H. Nishihara. Inorg. Chem. 2006, 45, 14-16. [2] M. Murata, S. Habe, S. Araki, K. Namiki, T. Yamada, N. Nakagawa, T. Nankawa, M. Nihei, H. Nishihara, Inorg. Chem. 2006, 45, 1108-1116. [3] S. Tsukada. Y. Shibata, R. Sakamoto, T. Kambe, T. Ozeki, H. Nishihara, Inorg. Chem. 2012, 51, 1228-1230.

Keywords: Metalladithiolene, communication, Cluster complex

Internuclear

electronic

MS.C3.P.517 Syntheses and Photophysical Properties of Z-Shaped Heteropolynuclear Complexes Keisuke Umakoshi, Ami Higashitani, Yasunori Kanematsu, Yasuhiro Arikawa, Graduate School of Engineering, Nagasaki University, (Japan). E-mail: [email protected] Heteropolynuclear transition-metal complexes have been attracting much attention, because they are expected to exhibit characteristic interactions and cooperative effects between the transition elements and provide novel functions that can not be obtainable by one kind transition metal element. We have recently reported that the 3,5-dimethylpyrazolate (Me2pz)-bridged heteropolynuclear complexes [Pt2M4(m-Me2pz)8] exhibit cluster-centered bright luminescence and the emission energy can be controlled by the change of the incorporated coinage metal ions [1,2]. These complexes have absorption bands in UV region. In order to shift the absorption bands towards lower energy, we planed to introduce diimine ligands into the heteropolynuclear complexes. Here we will report the syntheses, structures, and photophysical properties of Z-shaped heteropolynuclear complexes. The reaction of mononuclear Pt(II) complexes containing 3-t-butylpyrazole (3-t-BupzH) and 2,2’-bipyridine (bpy) or its derivatives [Pt(L)(3-t-BupzH)2](PF6)2 with coinage metal ions (MI = AgI, AuI, CuI) afforded Z-shaped heteropolynuclear complexes [Pt2M2(L)2(m-3-t-Bupz)4](PF6)2 (L = bpy, 4,4’-dmbpy, 5,5’-dmbpy, bpym). The Pt2Ag2 and Pt2Au2 complexes exhibit blue to green luminescence in the solid state, while Pt2Cu2 complexes exhibit orange luminescence.

[1] K. Umakoshi, T. Kojima, K. Saito, S. Akatsu, M. Onishi, S. Ishizaka, N. Kitamura, Y. Nakao, S. Sakaki, Y. Ozawa, , Inorg. Chem., 2008, 47, 5033-5035. [2] K. Umakoshi, K. Saito, Y. Arikawa, M. Onishi, S. Ishizaka, N. Kitamura, Y. Nakao, S. Sakaki, Chem. Eur. J., 2009, 15, 4238-4242. Keywords: platinum, coinage metals, luminescence

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MS.C3.P.518 Synthesis and Electronic Structure Study of an Oxo-centered Triruthenium Complex Steven Vancoillie,a Tamíris Lambert,b Kristine Pierloot,a André Formiga,b aComputational Coordination Chemistry, KU Leuven, Leuven (Belgium). bInstitute of Chemistry, UNICAMP, Campinas (Brazil). E-mail: [email protected] A new route was stablished to overcome the long standing problem of acetate contamination during the synthesis of [Ru3O(OAc)6(H2O)3] OAc.[1] Starting from Ru(OH)3 instead of the Ru(III) chloride salt it is possible to obtain a pure solid sample of the title complex in 89% yield. With this sample it was possible to determine the correct value of the molar extinction coefficient (1877±85 Lmol-1cm-1 at 670nm) and the actual UV-Vis spectrum of the compound. The differences were mainly in the relative intensity of the so-called intracluster bands. The electronic structure of the trinuclear ruthenium complex depends on its oxidation state, which can vary from Ru3OII,II,II to Ru3OIV,IV,III in a series of five reversible, mono-electronic redox steps. In this work, we focus on the Ru3OIII,III,III oxidation state, where each Ru center has a formal 4d5 configuration. In that case, each site has a single unpaired electron, which couple to form a doublet spinfrustrated ground state. The local environment of the Ru sites is pseudooctahedral, giving rise to a very broad range of ligand-field states. The occurrence of several intense bands in the visible range of the spectrum has been attributed to so-called intracluster transitions, involving the central oxygen atom [1,2]. In this work we take a closer look at the nature of the latter transitions by means of multiconfigurational perturbation theory using the MOLCAS quantum chemistry software [3]. We also compare our results to previous attempts to compute the spectrum with the ZINDO method [2].

[1] J. A. Baumann et al, Inorg. Chem., 1978, 17, 3342-3350. [2] A. L. B. Formiga PhD Thesis, 2005, University of São Paulo. [3] F. Aquilante, L. De Vico, N. Ferré, G. Ghigo, P.-A. Malmqvist, P. Neogrady, T. B. Pedersen, M. Pitonak, M. Reiher, B. O. Roos, L. Serrano-Andres, M. Urban, V. Veryazov, R. Lindh, J. Comput. Chem., 2010, 31, 224-247.

Keywords: oxo-centered triruthenium, UV-Vis spectroscopy, multiconfigurational perturbation theory

MS.C3.P.519

MS.C3.P.520

J(CP) of PPh3 Ligand as a Measure of Metal Center Electron Acceptor Ability Yu.S. Varshavsky, T.G. Cherkasova, M.R. Galding, V.A. Gindin, S.N. Smirnov, I.S. Podkorytov, O.V. Sizova, St. Petersburg University, Universitetskii pr., 26, St. Petersburg (Russia). E-mail: yurelv@gmail. com

Radiometal Complexation of Macrocyclic Ligands, Kinetic and Competitive Studies Ioana M. Vasilescua, Eskender Mumeb,c and Suzanne V. Smith,b,d a Chemistry, James Cook University, Australia. bCAMS at ANU, Australia. cCAMS at ANSTO, Australia. dCollider Accelerator Department, Brookhaven National Laboratory, Upton, NY. E-mail: [email protected]

1

A comparison of 13C NMR parameters shows a drastic increase of ipso carbon to phosphorus coupling constant, 1J(CP), on passing from triphenylphosphine to its oxide (our data given below agree well with [1, 2]). As may be supposed, this increase is mainly caused by binding phosphorus atom with a strong electron acceptor partner, oxygen atom. If so, one would expect that the 1J(CP) values for PPh3 ligand coordinated to the electron acceptor transition metal center, LxM←PPh3, would lie within the interval limited by these two endpoints. Experimental data and results of the DFT study provide support for this hypothesis by the example of a family of closely related rhodium carbonyl phosphine complexes containing β-diketonate and β-ketoiminate ligands. When complexes of the family are arranged in ascending order of ν(CO) carbonyl stretching frequency i. e. in ascending order of net electron acceptor ability of the rhodium center, the 1J(CP) values increase in the same order (calculated values in parentheses; Ketim is β-ketoiminate ligand, CF3C(O)CHC(NH)CH3; its complex is of P-trans-N geometry): 1 J(CP)/Hz Compound ν(CO)/cm-1 PPh3 ─ 10.6 (12.0) Rh(Ketim)(CO)PPh3 1975 47.2 Rh(Acac)(CO)PPh3 1982 50.9 (49.9) Rh(TFA)(CO)PPh3 1992 52.4 Rh(HFA)(CO)PPh3 2000 53.8 (54.6) Rh(Acac)(CO)PPh3I2 2088 57.4 OPPh3 ─ 103.9 (107.7) The data listed suggest that the ipso carbon coupling constant, J(CP), in the 13C spectrum of PPh3 ligand may serve, along with commonly applied carbonyl group stretching frequency [3, 4, 5 and references therein], as one more yardstick for the net electron acceptor ability of metal centers over a wide range of LxM←PPh3 complexes, presumably both carbonyl and non-carbonyl. Thereby it may also serve as an indirect measure for the resultant electron donor/acceptor ability of ligand L′ in families of L′LxM←PPh3 complexes with unvaried LxM part. DFT study showed that electronic characteristics of PPh3 ligand in Rh(Acac)(CO)PPh3 and Rh(HFA)(CO)PPh3 lie near the middle of the interval between values for PPh3 and OPPh3 molecules. In this regard these characteristics behave like experimental and calculated 1 J(CP) values and thus bear more evidence in support of the concept suggested. 1

[1] J. Schraml, M. Čapka, V. Blechta, Magn. Res. Chem., 1992, 30, 544-547. [2] T. A. Albright, W. J. Freeman, E. E. Schweizer. J. Org. Chem., 1975, 40, 34373441. [3] S. Otto, A. Roodt, Inorg. Chim. Acta, 2004, 357, 1-10. [4] O. Kühl, Coord. Chem. Rev., 2005, 249, 693-704. [5] Yu.S. Varshavsky, M.R. Galding, T.G. Cherkasova, S.N. Smirnov, V.N. Khrustalev, J. Organomet. Chem., 2007, 692, 5788–5794.

Keywords: triphenylphosphine ligand, 13C NMR, DFT

Metal complexes of mixed donor macrocycles have been studied in an attempt to understand the factors underlying metal ion recognition and discrimination.[1], [2], [3] A recently completed matrix of eighteen 17-membered macrocyclic ligands incorporating symmetrical and unsymmetrical arrangement of N, S and/or O donors has enabled a comparative analysis of their metal binding properties with a range of industrially important metal ions.[4], [5] Potentiometric determination of metal binding constants (log K) showed these ligands favour the formation of 1:1 metal:ligand complexes.[1] While log K values are determined at equilibrium under constant ionic strength and temperatures, they are a good indication of the stability of a metal complex. Equilibria for log K studies may take hours to days to establish. For environmental and industrial application it is important to understand the kinetics of metal ion binding of these ligand systems at lower concentrations, varying pH and temperatures and the presence of different potentially binding electrolytes. However, for many analytical methods this can be quite challenging. One approach is to use gamma emitting radioisotopes of the metal ions of interest, since their gamma emitting signals are not affected by these conditions. This study investigates the complexation behaviour of selected macrocyclic ligands with Co(II) and Ag(I) using the radioisotopes 57Co (t1/2 = 271.7 d; gamma emission = 122.1 and 136.5 keV) and 110mAg (t1/2 = 249.8 d; gamma emission = 657.7 keV). Existing protocols[6] for monitoring complexation behaviour using thin layer chromatography (TLC) were adapted for the current study. The metal binding of Co(II) and Ag(I) by a number of ligands was conducted in the absence and presence of competing metal ions such as Cu(II) at varying pH. The TLC mobile phases were validated for the identification of free and complexed metal ions. The percent of Co(II) and Ag(I) complexed was measured in various types of buffer solutions and pH. The results show that Ag(I) complexed rapidly (within minutes) while Co(II) was slower, requiring up to 60 minutes to reaction equilibrium. The percent complexation compared favourably with the log K data, with values of 56 % and 16% for Co(II) (log K values for the metal complexes of 9.2 and 6.2 respectively) and 47 % for Ag(I) (log K 8.7). The presence of competing metal ions can interfere with Ag(I) binding even if the log K is comparatively lower. The results not only successfully illustrate the value and feasibility of using radioisotopes to study the coordination behaviour of ligand systems, but also how the data can assist with testing the systems for practical applications. [1] L. F. Lindoy, Pure & Appl. Chem., 1997, 69, 2179. [2] P. Comba and W. Schiek, Coord. Chem. Rev., 2003, 238, 21. [3] L. F. Lindoy et al., Coord. Chem. Rev., 2010, 254, 1713. [4] I. M. Vasilescu et al., Dalton Trans., 2011, 40, 8675. [5] Ioana M. Vasilescu et al., Supramol. Chem., GSCH 688130 in press. [6] Nadine M. Di Bartolo et al., J. Chem. Soc., Dalton Trans., 2001, 2303.

Keywords: macrocycle, radiometal, silver We thank the Australian Institute of Nuclear Science and Engineering for support.

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Poster Sessions

Poster Sessions MS.C3.P.521

MS.C3.P.522

Ruthenium(II) Complexes of Tolylterpyridine Appended Calixarenes and Calixresorcarenes Alexander Vedamanickam and Amudhan Senthan Selvam, Department of Chemistry, Loyola College, Chennai (India). E-mail: valexander@ rediffmail.com

The Nature of Solvent Involvement in the CO-Insertion of the Rhodium Cupferrates Johan Venter, Walter Purcell, Andreas Roodt, Department of Chemistry, University of the Free State, Bloemfontein, (South Africa). E-mail: [email protected]

Calixarenes and calixresorcarenes are a versatile class of macrocycles because of the possibility of functionalization of both the upper and lower rims in a regio- and stereocontrolled way. Polynuclear complexes made up of the achiral [Ru(ttpy)2]2+ (ttpy = 4′-(p-tolyl)-2,2′:6′,2″-terpyridine) motif forms stereopure assemblies. Polynuclear ruthenium(II) complexes of tolylterpyridine appended calixarenes and calixresorcarenes and their photophysical and electrochemical properties are reported. 5,11,17,23-Tetra-tert-butyl25,26,27,28-tetrahydroxycalix[4]arene (1) is synthesized by the basecatalyzed condensation of p-tert-butylphenol with formaldehyde. 2,8,14,20-Tetraphenyl4,6,10,12,16,18,22,24-octahydroxycalix[4] resorcarene (2) and 2,8,14,20-tetra-p-tolyl-4,6,10,12,16,18,22,24octahydroxycalix[4]- resorcarene (3) are synthesized by the acid catalyzed condensation of resorcinol with benzaldehyde and p-tolualdehyde, respectively. The compounds 1-3 are characterized by single crystal X-ray diffraction. Tolylterpyridine appended calix[4]arene L1 and calix[4]resorcarenes L2 and L3 are synthesized by the O-alkylation of the preformed macrocycles 1-3 with 4′-(p-bromomethylphenyl)-2,2′:6′,2″-terpyridine, respectively. The tetranuclear complex [{Ru(ttpy)}4(L1)](PF6)8 (4) and the octanuclear complexes [{Ru(ttpy)}8(L2)](PF6)16 (5) and [{Ru(ttpy)}8(L3)](PF6)16 (6) are synthesized by the reaction of the precursor complex [Ru(ttpy) Cl3] with the preformed macrocycles L1-L3, respectively. The polynuclear Ru(II) complexes exhibit metal centered luminescence both in the solid state at room temperature and in acetonitrile at 77 K. The methodology developed in the present work can be exploited to synthesize macrocycle-based polypyridine ligands and polynuclear assemblies. All the RuII-ttpy chromophores are photochemically and electrochemically equivalent.

In both the Monsanto and Cativa processes, CO-insertion is an essential step in the catalytic carbonylation of methanol to form acetic acid. In the Cativa process, CO-insertion is even the rate determining step. Previous work in our group was concerned with the oxidative addition and CO-insertion reactions of rhodium complexes [1]. An often neglected field of study, that of the effects of solvents on the outcome and progress of reactions, was conducted to get a better understanding of CO-insertion. The successful isolation of the alkyl product of the oxidative addition reaction of CH3I with [Rh(cupf)(CO) (PPh3)] [2] enabled the study of the subsequent CO-insertion reaction without the complications of consecutive reactions which are normally associated with these systems. A further advantage of this particular system was that the alkyl formation goes to completion without any sign of reductive elimination as the reverse reaction. The CO-insertion reaction proceeds spontaneously with the dissolution of the crystalline Rh(III)-alkyl complex in a suitable solvent to form the Rh(III)-acyl product [3]. The effect of the different electronic and steric properties of the solvents on the rate of insertion could be studied by varying the solvent (the proposed incoming ligand in this system). A series of methyl substituted tetrahydofurans, which vary widely in donocity and stereochemical design, but with constant dielectric properties, was used amongst other solvents to resolve the nature of solvent participation. The mechanism of the CO-insertion reaction was further investigated by studying the effect of competing solvents. This was done by dissolving [Rh(cupf)(CO)(CH3)(I)(PPh3)] in a range of DMSO/benzene mixtures and monitoring the Rh(III)-acyl formation. The steric and electronic influence of the coordinated phosphine ligand on the rate and mechanism of the acyl formation were also investigated by employing different [Rh(cupf)(CO)(CH3)(I)(PX3)] complexes (PX3 = PPh3, P(p-ClC6H4)3, P(p-MeOC6H4)3 and PCy3) as starting material. Kinetic results obtained through infra-red and visible spectrophotometry will be presented to propose the most appropriate mechanism. The solvents participate in a coordinative way, rather than just stabilizing the migratory insertion transition state by solvation and can be regarded as an example of a solvent catalyzed reaction. [Rh(cupf)(CO)(CH3)(I)(PX3)] + Solv [Rh(cupf)(COCH3)(I)(PX3)(Solv)] [1] (a) G.J.J. Steyn; A. Roodt, J.G. Leipoldt, Inorg. Chem., 1992, 31, 34773481; (b) A. Roodt, G.J.J. Steyn, Recent Res. Devel. Inorg. Chem., 2000, 2, 1-23; (c) A. Brink, A. Roodt, G. Steyl, H.G. Visser, Dalton Trans., 2010, 39, 5572-5578. [2] (a) S.S. Basson; J.G. Leipoldt, A. Roodt, and J.A. Venter, Inorg. Chim. Acta, 1987, 128, 31-37; (b) J.A. Venter, J.G. Leipoldt, and R. van Eldik, Inorg. Chem., 1991, 30, 2207-2209; (c) J.A. Venter, W. Purcell, H.G. Visser, T.J. Muller, Acta Cryst., 2009, E65, m1578. [3] J.A. Venter, W. Purcell, H.G. Visser, Acta Cryst., 2009, E65, m1528 -m1529.

Keywords: calixarene, calixresorcarene, Ru-polypyridyl complexes

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Keywords: rhodium, catalysis, CO-insertion

Poster Sessions

Elucidating Complexes Using Solution and Solid State as Complimentary Techniques Vanessa L. Vieira, Caren Billing, Demetrius C. Levendis, Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg, (South Africa). Email: [email protected]. ac.za Polarography was used to study complex formation of various cadmium-pyridinecarboxylic acids starting in the very acidic region (pH < 2) where not much research has been conducted due to the limitations of the more popular electrochemical technique of glass electrode potentiometry. New complexes in the acidic region were tentatively proposed since substantial adjustments were made to low pH data in order to compensate for the diffusion junction potential. This uncertainty in the proposed solution species inspired the combined analysis of coordination compounds existing in solution and grown in the solid state. Polarographic data was analyzed by predicting species that would potentially be in solution and then estimating their formation constants. These values were refined in accordance with the experimental data to obtain calculated formation constants. Species distribution diagrams (SDDs) were plotted to indicate which species predominate in a particular pH region. Crystals were then grown according to the pH conditions that were predicted by the SDDs. Solution studies performed on a cadmium-picolinic acid system indicated the existence of a CdLH (where L = ligand) coordination compound at pH < 2, which had previously not been identified. Crystal growth at approximately pH 0.5 validated the presence of this species. A slightly different scenario occurred with the cadmium-quinolinic acid system where a crystal grown at pH 1.2 produced the structure of a novel and unexpected (according to the initial solution species model) coordination compound, Cd(LH)3. This led to the suggestion of it possibly also existing in solution at low pH, which was corroborated when re-evaluating the solution data by including the Cd(LH)3 species in the model. In doing so the overall standard deviation of the fit improved by 60 % on average. Keywords: solution species, crystal structure, pH dependant

MS.C3.P.524 Coordination Chemistry as a Training Tool for the Undergraduate Student Bubele Vuba, Sizwe Makhoba and Alfred Muller, Research Centre for Synthesis and Catalysis, Department of Chemistry, University of Johannesburg (APK Campus), Johannesburg (South Africa). E-mail: [email protected] Selected undergraduate chemistry students (2nd and 3rd year) at the University of Johannesburg were introduced to basic coordination chemistry concepts through a series of mini-projects done on a part-time basis. This introduced students at an early stage to important aspects of research methodology and a better understanding of coordination chemistry, all of which they can apply to their undergraduate studies. The mini research projects entailed synthesis and characterization of model coordination complexes of various well-known Vaska type complexes with the general formula trans-[M(X)(Y)(L)2] (M = 2nd and 3rd row group 9, 10 transition metals; X = halogen or pseudo halogen; Y = carbonyl or halogen; L = tertiary group 15 ligand). Before proceeding with their experiments, students had to first compile a literature survey and be fully aware of safety protocols in the synthetic laboratory. Once the model compounds were synthesized, students had to characterise

these using various techniques. The techniques played a major part in their education as students had to master these to interpret results from their findings. Where possible the results were published [1], [2], thereby improving the writing skills of the student. As a final step the results were combined and students had to discuss differences and similarities of these compounds. Presented here are the combined mini-project results from these students and their interpretation of the characterization techniques used, i.e. IR, NMR, UV/Vis and X-ray crystallography. [1] B. Vuba and A. Muller, Acta Cryst., 2012, E68, m14-m15. [2] S. Makhoba, A. Muller, R. Meijboom and B. Omondi, Acta Cryst., 2011, E67, m1286– m1287.

Keywords: teaching, undergraduate, model complexes

MS.C3.P.525 Complete Spontaneous Resolution of 3d–4f–3d Type Heterotrinuclear Complexes Koki Wada, Manami Isozaki, Tomoka Yamaguchi, Takayoshi Suzuki, Yukinari Sunatsuki, Masaaki Kojima, Graduate School of Natural Science and Technology, Okayama University, Okayama (Japan). E-mail: [email protected] Spontaneous resolution is one of the most interesting phenomena in nature, and serves the simplest method to resolve a race-mate into two enantiomers (forming a conglomerate). Recently, a new phenomenon called “total spontaneous resolution” has been reported for coordination and organometallic compounds [1]. In this process the resulting bulk products were nearly enantiopure single crystals without seeding (i.e., preferential crystallization) or stirring (i.e., attritionenhanced deracemization [2]); however, it could not be expected which enantiomer was obtained in each batch. Here, we report a serendipitous finding of a fascinating phenomenon that spontaneous resolution of a kind of trinuclear complex (racemate) gave optically active single crystals with a certain chirality in every experiments. This may be termed as “complete spontaneous resolution”. In a previous report [3], we have prepared heterotrinuclear MII– III Ln –MII (M = Mn, Fe, Co, Zn; Ln = Eu, Gd, Tb, Dy) com-plexes (Fig. 1) containing a tripodal potentially nonadentate ligand, 1,1,1-tris[(3methoxysalicylideneamino)methyl]ethane (H3L), by a reaction of H3L, M(CH3COO)2·2H2O, and Ln(NO3)3·6H2O (2:2:1 molar ratio) in the presence of NEt3 in methanol. In the case of M = Zn and Ln = Tb, the crystals of [(ZnL)2Tb]NO3·2MeOH (1) were deposited. It was revealed by X-ray analysis that compound 1 crystallized in a chiral space group P212121. Each single crystal of 1 from different experiments (batches) gave the same CD spectral pattern. Furthermore, crystalline powder obtained by rapid crystallization from the reaction mixture also gave the CD spectra with signals of the same magnitude. This is indicative of the complete spontaneous resolution achieved in the crystallized step. We have also observed similar phenomena for the other Ln compounds and the corresponding Mn complexes. When compound 1 was recrystallized from CH2Cl2 and DMF by vapour diffusion of Et2O, crystals of [(ZnL)2Tb]NO3·2CH2Cl2 (2) and [(ZnL)2Tb]NO3·2DMF (3) were deposited, respectively. Crystal structure analysis of 2 revealed the chiral space group of P212121. However, the CD spectra of crystalline powder of 2 exhibited enantiomeric patterns, dependent on the batches. This may indicates that total, but not complete, spontaneous resolution was achieved in this case. The compound of 3 crystallized in the achiral space group P21/n, and showed no signals in the CD spectrum as expected. It was also found that the corresponding FeII complex, [(FeL)2Tb]ClO4·MeOH, exhibited (ordinary) spontaneous resolution; single crystals resulted from a batch showed CD spectrum with the enantiomeric pattern.

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MS.C3.P.523

Poster Sessions We have also examined the effect of additional chiral impurities and the magneto-chiral effect on “complete spontaneous resolution”, and the results will also be presented in the poster.

Fig. 1. The schematic drawing of [(ZnL)2Tb]+ [1] A. Lennartson, M. Håkansson, Angew. Chem. Int. Ed., 2009, 48, 5869–5871, and references therein. [2] P. J. Skrdla, Cryst. Growth Des., 2011, 11, 1957– 1965. [3] T. Yamaguchi et al., Inorg. Chem., 2010, 49, 9125–9135.

Keywords: face-sharing trinuclear complexes, circular dichroism spectra, chiral crystals

MS.C3.P.526 Self-Assembly of Transition Metal Ion Complexes of a Hybrid Pyrazine-Terpyridine Ligand Monika Wałęsa-Chorab,a Artur R. Stefankiewicz,a,b,c Maciej Kubicki,a Zbigniew Hnatejko,a Violetta Patroniak,a Jean-Marie Lehn,b a Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60780 Poznań (Poland). bInstitut de Science et d’Ingénierie Supramoléculaires, Université de Strasbourg, 8, allée Gaspard Monge, 67083 Strasbourg (France). cUniversity Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW (United Kingdom). E-mail: [email protected] Supramolecular chemistry is one of the most important innovations in inorganic, organic and biochemistry in the last decades. Supramolecular chemistry relies on the use of non-covalent interactions to self-assemble, with a precision in the sub-nanometer scale, chemical entities forming materials with programmed chemical and physical properties. By suitable selection of metal ions preferring specific coordination geometry and structure of coordination sites of the ligand it is possible to obtain well-defined and relatively stable complexes like grids, squares, double, triple (and higher) and circular helicates, racks, cages and coordination polymers. The formation of such supramolecular architectures depends on many factors, such as the nature, flexibility and geometry of the binding subunits, the presence of specific molecules and anions, and the nature of the medium. The abundant complexes of transition metal ions with heterocyclic-N-donor ligands are used in many fields of science, for example, in medicine, nanotechnology, optoelectronics and catalysis. Following on from our successful synthesis of certain quaterpyridine transition metal complexes,[1-3] we became interested in the double-quaterpyridine ligand L 2,3-bis(6-(6-(pyridin-2-yl) pyridin-2-yl)pyridin-2-yl)pyrazine containing two N4-donor subunits. Reactions of ligand L with different transition metal ions (Mn(II), Zn(II), Fe(II), Co(II), Cu(II) and Cd(II)) gave rise to formation of new supramolecular architectures. In the presence of nitrate counteranion, both Cu(II) and Cd(II) give complexes in which the ratio M:L is 2:1, whereas with perchlorate, trifluoromethanesulfonate or tetrafluoroborate, the other metal ions provide solids in which this ratio is 1:1. Compounds have been characterized by spectroscopic

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techniques and elemental analysis. The solid state structures of ligand L and Fe(II) complex have been established by X-ray crystallography.

Luminescence properties of obtained compounds have been also examined. Project supported by: grant 2011/01/N/ST5/02235 from the Polish National Science Centre. [1] A. R. Stefankiewicz M. Wałęsa, P. Jankowski, A. Ciesielski, V. Patroniak, M. Kubicki, Z. Hnatejko, J. M. Harrowfield, J.-M. Lehn, Eur. J. Inorg. Chem., 2008, 2910-2920. [2] A. Ciesielski, A. R. Stefankiewicz, M. Wałęsa-Chorab, V. Patroniak, M. Kubicki, Z. Hnatejko, J. M. Harrowfield, Supramolecular Chem., 2009, 21, 48-54. [3] A. Ciesielski, V. Patroniak, M. Kubicki, J. Chem. Crystallogr., 2011, 41, 1884-1888.

Keywords: self-assembly, complexes of transition metal ions, pyrazine-terpyridine ligand

MS.C3.P.528 Coordination Chemistry of Bimetallic Platinum(II) Diphosphinomethane Complexes Sophie Wernitz,a Wolfgang Leis,a Caecilia Maichle-Mössmer,a Hermann A. Mayer,a aInstitute of Inorganic Synthesis, University of Tübingen, Tübingen, (Germany). E-mail: [email protected] Monometallic platinum(II) complexes of the type (PCH2P) PtMe2 (PCH2P = bis(dicyclohexylphosphino)methane (dcpm), bis(diphenylphosphino)methane (dppm)) show interesting reaction behaviour when treated with acids with weakly coordinating anions [1,2]. For dppm it has been shown that either one or two methane molecules can be removed, both resulting in bimetallic platinum(II) complexes in which dppm functions as a bridging ligand between two platinum atoms [1,2]. The synthesis of the new bimetallic dicationic platinum(II) complex [Pt2Me2(μ-dcpm)2]2+ was successful and the synthesis of [Pt2Me2(μ-dppm)2]2+ was improved. Reactions of [Pt2Me2(μ-dcpm)2]2+ and [Pt2Me2(μ-dppm)2]2+ with a number of bidentate ligands of the type YZY (Y = PR2, Z = CH2; Y = S, Z = CNR2, COR, PR2) resulted in the formation of new bimetallic compounds. Depending on the ligand YZY used different coordination behaviour was observed. The bidentate ligand YZY coordinated in two main fashions: bridging the two platinum(II) centres and generating complexes of the type [Pt2Me2(μ-PCH2P)2(μ-YZY)]+ or chelating one platinum(II) centre and thus opening one PCH2P-bridge, generating complexes of the type [(YZY)(Me)Pt–(μ-PCH2P)–Pt(Me)(PCH2P)]m+ (m = 1, 2). Some general mechanistic aspects of the performed reactions were discussed. [1] M.P. Brown, S.J. Cooper, R.J. Puddephatt, M.A. Thomson, K.R. Seddon, J. Chem. Soc. Chem. Comm., 1979, 1117-9. [2] A.T. Hutton, B. Shabanzadeh, B.L. Shaw, J. Chem. Soc. Chem. Comm., 1983, 1053-5.

Keywords: bimetallic complexes, coordination behaviour

bidentate

PCP

ligands,

Poster Sessions MS.C3.P.529 M4o4 Cubanes: Synthetic Principles and Properties Alan M. Downward, Alan F. Williams, Claire Deville, Department of Inorganic Chemistry, University of Geneva, Geneva (Switzerland). E-mail: [email protected]

complexation reactions of the reduced macrocycle exhibits varying extents of oxidative dehydrogenation, which in turn is shown to be associated with changes in field strength, tuning the spin state of Ni(II).

The M4O4 cubanes (below left) are complexes where four metals are linked by four bridging oxygen ligands. They are readily accessible systems which allow close M-M interactions and which can show a wide variety of metal oxidation states between M(0)4 and M(IV)4. Some hundreds of these complexes have been reported [1] but they are rarely discussed as a family. We show the principles underlying these structures and how they can be used to design new ligands for cubane formation. In particular combining diagonally bridging and chelating ligands allows the generation of unusual structures such as a quadruple helix of controlled chirality (below right). We report on the properties of the complexes including enantioselectivity of helicate formation, substitution kinetics, magnetism and redox chemistry.

[1] a) N. F. Curtis, Y. M. Curtis, H. K. J. Powell, J. Chem. Soc. A 1966, 10151018; b) C. J. Hipp, L. F. Lindoy, D. H. Busch, Inorg. Chem. 1972, 11, 19881994. [2] a) V. L. Goedken, J. Chem. Soc., Chem. Commun. 1972, 207-208; b) N. F. Curtis, Coord. Chem. Rev. 1968, 3, 3-47. [3] C. L. Weeks, P. Turner, R. R. Fenton, P. A. Lay, J. Chem. Soc., Dalton Trans. 2002, 931-940. [4] a) R. Li, T. A. Mulder, U. Beckmann, P. D. W. Boyd, S. Brooker, Inorg. Chim. Acta 2004, 357, 3360–3368; b) S. A. Cameron, S. Brooker, Inorg. Chem. 2011, 50, 36973706. [5] D. S. C. Black, N. E. Rothnie, Aust. J. Chem. 1983, 36, 2395-2406. [6] R. Sanyal, S. A. Cameron, S. Brooker, Dalton Trans. 2011, 40, 12277-12287.

Keywords: oxidative dehydrogenation, spin state, macrocycle

MS.C3.P.531 Keywords: cubanes, polynuclear complexes, self-assembly

MS.C3.P.530 Stepwise Oxidative Dehydrogenation of a Tetra-Amine N4 Macrocycle Tunes the Nickel(II) Spin State Rajni K. Wilson,a Scott A. Cameron and Sally Brooker,b,* aDepartment of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology, University of Otago, PO Box 56, Dunedin 9054, New Zealand. E-mail: [email protected] Macrocyclic Ni(II), Cu(II) and Fe(II) complexes have been known to undergo oxidative dehydrogenation.[1] Atmospheric oxygen readily performs the ligand dehydrogenation for Fe(II),[2] and for Ni(II). [3] In the case of Ni(II), molecular oxygen and the dissolution of the complex in a basic solution[3] is required in order to increase the degree of unsaturation of the ligand. This research group has a long standing interest in pyrrolebased dicarbonyl head units that can be used to prepare porphyrinlike macrocyclic complexes.[4] Selected results of “one pot” metal ion templated Schiff base condensations of 2,2’-iminobisbenzaldehyde[5] with diethylenetriamine, and of metallations of the metal-free macrocycle, will be presented,[6] along with more recent results obtained using the sodium borohydride reduced version of this macrocycle (Figure). A family of Ni(II) complexes obtained from

Multimetallic Assemblies and Functionalised Nanoparticles James D. Wilton-Ely,a Saira Naeem,a Graeme Hogarth,b Simon Sung,a Holly Holmes,a aDepartment of Chemistry, Imperial College London, London (UK). bDepartment of Chemistry, University College London, London (UK). E-mail: [email protected] Bringing more than one metal into the same region of molecular space opens up the possibility of harnessing different and complementary properties. This combination of chemical and physical attributes can find application in areas as diverse as catalysis, multimodal imaging and cancer therapy. The preparation of bimetallic compounds is often confined to symmetrical, homobimetallic species. This limitation can be overcome through the use of linkers with different donor combinations or stepwise construction of the multimetallic targets. Both approaches will be demonstrated in this contribution, which principally explores 1,1-dithio ligands [1-6], but also includes oxygen and nitrogen donors to construct a wide range of functional molecules. The historic, yet often overlooked dithiocarbamate ligand class will used to demonstrate the construction of compounds in which 2-6 metals are joined. If pendant functional groups are included (e.g., allyl, amine groups), further modification to the coordinated dithiocarbamate is also possible [4]. In addition, the same methodology can be used to functionalize the surface of gold nanoparticles with transition metal units [5,6]. These soluble materials can be characterized by solution NMR as well as Transmission Electron Microscopy (TEM). Their application in catalysis and medical imaging will be discussed.

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[1] A. F. Williams, Dalton Trans. 2008, 818-821.

Poster Sessions MS.C3.P.533 Oxo-acetato Triruthenium Complexes with Dinitrogen as Terminal Ligand Tadashi Yamaguchi, Genki Iwasaki, Hiroyoshi Ohtsu, Department of Chemistry and Biochemistry,Waseda University, Tokyo (Japan). E-mail: [email protected]

[1] J. D. E. T. Wilton-Ely, D. Solanki, E. R. Knight, K. B. Holt, A. L. Thompson, G. Hogarth, Inorg. Chem., 2008, 47, 9642-9653; [2] M. J. Macgregor, G. Hogarth, A. L. Thompson, J. D. E. T. Wilton-Ely, Organometallics, 2009, 28, 2009, 197-208; [3] K. Oliver, A. J. P. White, G. Hogarth, J. D. E. T. WiltonEly, Dalton Trans., 2011, 40, 5852-5864; [4] S. Naeem, G. Hogarth, A. J. P. White, J. D. E. T. Wilton-Ely, Organometallics, 2010, 29, 2547-2556; [5] E. R. Knight, N. H. Leung, A. L. Thompson, G. Hogarth, J. D. E. T. Wilton-Ely, Inorg. Chem., 2009, 48, 3866-3874; [6] E. R. Knight, N. H. Leung, Y. H. Lin, A. R. Cowley, D. J. Watkin, A. L. Thompson, G. Hogarth, J. D. E. T. Wilton-Ely, Dalton. Trans. 2009, 3688-3697.

Keywords: Multimetallic, Sulfur-ligands, Nanoparticles

MS.C3.P.532 Nitrosoaryl Ruthenium Complexes Prepared by Direct Insertion of Nitrosonium Ion into Ruthenium–Aryl Bond Chun-Yuen Wong, Siu-Chung Chan, Department of Biology and Chemistry, City University of Hong Kong. E-mail: acywong@cityu. edu.hk An insertion reaction of nitrosonium ion (NO+) into the metal– carbon bond of cyclometalated ruthenium(II) complexes to give nitrosoaryl ruthenium complexes is presented. Experimental evidence support a bimolecular direct NO+ insertion into the metal–carbon bond (i.e. M–R + NO+ → [M–N(=O)–R]+) but not an intramolecular migratory insertion (i.e. R–M–(NO) + L → L–M–N(=O)R) as the reaction mechanism [1]. Structural, electrochemical, spectroscopic and theoretical investigations on the nitrosoaryl complexes suggest that the coordinated nitrosoarene should be regarded as a neutral π-acid moiety rather than monoanionic radical or diamagnetic dianion [2].

Oxo-acetato triruthenium complexes, [Ru3O(CH3CO2)6(L)3]n+ (L= monodentate ligand) affords a versatile class of compounds possessing rich redox chemistry. [1] When one of the terminal ligand is CO, isolated complexes are chargeless in which the ruthenium attached by CO is Ru(II) and the other two ruthenium is Ru(III). Although triruthenium complexes with isoelectronic nitrosyl (NO+) ligand possess also chargeless, the NO+ ligand act as non-innocent ligand and thus the complex shows a character in-between those of {Ru(III,III,III)}+-NO0 and {Ru(III,III,III)}0-NO+ states. [2] In this study, we report synthesis and non-innocent property of oxoacetatotriruthenium complexes with dinitrogen ligand that is also isoelectronic with CO. Reaction of [Ru3O(CH3CO2)6(dmap)2(H2O)]+ (dmap = 4-dimethylaminopyridine) with excess azide (N3–) affords [Ru3O(CH3CO2)6(dmap)2(N3)] and [Ru3O(CH3CO2)6(dmap)2(N2)]. The latter complexes should form proton-assisted decomposition of the former complexes similar to that of mononuclear dinitrogen ruthenium complexes. 1H NMR of the dinitrogen complexes possess paramagnetic shift which is characteristic for Ru(III,III,III), which is contrast to diamagnetic CO complex. Single crystal X-ray crystallographical analysis of [Ru3O(CH3CO2)6(dmap)2(N2)] reveals that N-N distance of dinitrogen is 1.173(8) Å. The distance is slightly longer than other N2 complexes (1.10-1.11 Å), and thus the dinitrogen ligand possesses N2– character. On the other hand, IR spectrum of the complexes shows n(NN) at 2110 cm–1 which is normal range of coordinated dinitrogen. Although 1H NMR and X-ray analysis suggest that the complex possess rather {Ru(III,III,III)}+-NO0 character than {Ru(III,III,III)}0NO+ character, IR suggests reverse result. Thus the complexes possess non-innocent property.

Figure Structure of [Ru3O(CH3CO2)6(dmap)2(N2)] [1] S.-C. Chan, P.-K. Pat, T.-C. Lau, C.-Y. Wong, Organometallics, 2011, 30, 1311-1314. [2] S.-C. Chan, H.-Y. Cheung, C.-Y. Wong, Inorg. Chem., 2011, 50, 11636-11643.

[1] H. E. Toma et al. Coord. Chem. Rev. 2001, 219-221,187-234. [2] H. E. Toma et al. Inorg. Chim. Acta 2005, 358, 2891-2899.

Keywords: ruthenium, nitrosonium, nitrosoarene

Keywords: multinuclear complex, dinitrogen complex, noninnocent ligand

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Poster Sessions MS.C3.P.534

MS.C3.P.535

Photodimerization of Hydrazone Metal Complexes Daisuke Yamamoto,a Atsushi Kobayashi,a Ho-Chol Chang,a Kiyohiko Nakajima,b Masako Kato,a aDivision of Chemistry, Faculty of Science, Hokkaido University, Hokkaido(Japan). bDepartment of Chemistry, Aichi Univ. of Education, Aichi (Japan). E-mail: yamamoto777@mail. sci.hokudai.ac.jp

A Selective Phthalocyanine Sensors for Palladium(II) and Silver(I) Ion in Solution M. Nilüfer Yaraşır, Mehmet Kandaz*, Melike Sevim, Yusuf Tekin, Department of Chemistry, Sakarya University, 54140 Esentepe, Sakarya, Turkey. E-mail:[email protected] A new optical chemical sensors (phthalocyanines) have been developed for the selective determination of palladium (II) and silver (I) ions in aqueous solutions [1-4]. The reversible sensing system were prepared by incorporating of peripherally functionali zed, 2,3,9,10,16,17,23,24-[octakis-(1,2-propandiol sulfanyl)]subs tituted metal (II) or metal (III) phthalocyanines and non-perip herally designed, 1(4), 8(11), 15(18),22(25)-tetrakis[3-(thiophen-3ylmethoxy)]substituted metal (II) or (III) phthalocyanines, (MPc) {(Zn(II), Cu (II), Co(II) and Mn(III)}. Both new type ligands and their complexes have been characterized by elemental analysis, FTIR, 1H-NMR, MALDI-TOF/MS, UV–Vis spectral data. Metal ion sensing properties on the non-periphery and periphery functional phthalocyanines induced aggregation result in significant changes of absorption of the Q- and B-bands [2-4]. The detection of Pd (II) and Ag (I) ion were investigated by all phthalocyanines in solution and ZnPc immobilized into poly siloxane matrix and based on the fluoroscence quenching of ZnPc upon titration with palladium and silver ion. Spectra of MPc exhibits distinct changes in visible and UV-region in response to treatment with palladium (II) and silver (I) ion in solution. The proposed fluorescent optode membrane displays a calibration response for palladium (II) and silver (I) over a wide concentration range of 1.0x10-2 to 1.0x10−6 M, with a relatively fast response [4]. In addition to high stability and reproducibility, the sensor shows a unique selectivity towards palladium (II) and silver (I) ion with respect to common co-existing cations.

[1] S.J. Lange, J.W. Sibert, A.G.M. Barrett, B.M. Hoffman., Tedrahedron. 2000, 56, 7371-77. [2] A. T. Bilgiçli, A. Günsel, M. Kandaz* A.R. Özkaya, Dalton Trans., 2012, 00, 1–11. [3] M. Kandaz, A. T. Bilgicli, A. Altındal, Synthetic Metals, 2010, 160, 52–60. [4] M. Kandaz, O. Güney, F.B.Senkal, Polyhedron, 2009, 28(14), 3110-3114.

Key words: phthalocyanines, metal sensor, fluoroscence

[1] M. Chang et al., Bull. Chem. Soc. Jpn, 2010, 83, 905-910.

Keywords: photoreaction, Pt(II) complex, hydrazone

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Hydrazones have attracted much attention because of their unique properties such as photoisomerization and photochromism. Taking advantage of coordination abilities of hydrazones, we previously synthesized a that the Pt(II)-hydrazone complex [PtCl(pbph)] (Hpbph = 2-(diphenylphosphino)benzaldehyde- 2-pyridylhydrazone) and found that this complex exhibits reversible protonation/deprotonation behavior in the solution state accompanied by drastic color change.[1] In order to clarify the photoreactivity of the metal-hydrazone complexes, our recent attention have focused on the photoreactivities of the Pt(II)-hydrazone complexes [PtCl(pbph)] and [PtCl(papy)] (Hpapy = 2-pyridinecarboxaldehyde-2-pyridylhydrazone). In this work, we report on the syntheses, structures and photoreactivities of these Pt(II)-hydrazone complexes. [PtCl(pbph)] and [PtCl(papy)] were synthesized by simple reactions of K2[PtCl4] and the corresponding hydrazone ligand in basic CH3CN solution under reflux. Figure 1 shows UV-Vis spectral changes of [PtCl(pbph)] in CH3CN solution under photoirradiation (lirr. = 524 nm). Before irradiation, intense Fig. 1 UV-Vis spectral changes of [PtCl (pbph)] under photoirradiation (λirr. = 524 absorption band assignable to the intra-ligand charge transfer nm). (ILCT) transition was observed at 524 nm. Under photoirradiation, the ILCT band decreased and a new absorption band appeared at 398 nm maintaing the isosbestic points at 268, 373 and 444 nm. X-ray structural determination for the single crystals obtained by natural evapolation of the reaction solution revealed that the photoproduct was composed of two metal-hydrazone complex units linked by the newly formed C-N bond as shown in Figure 2. Interestingly, another imine carbon was oxidized to form a carbonyl group. 1H NMR spectroscopy suggests that this photodimerization proceeded without forming any byproducts. On the other hand, ESI-MS spectrum of photoproducts of the planer-shaped Pt(II)-hydrazone complex [PtCl(papy)] suggests that similar photodimerization coupled with oxygenation occured but subsequent polymerization would be Fig. 2 Molecular structure of proceeded. Details will be photoproduct. discussed.

Poster Sessions MS.C3.P.536

MS.C3.P.537

Polymerization Reaction of Cobalt(III) Thiolato Complexes having Several Isomers Toshiaki Yonemura,a Kenji Matsumoto, a Tomohiro Ozawab a Department of Applied Chemistry, Kochi University, Kochi (Japan). b Graduate School of Engineering, Nagoya Institute of Technology, Nagoya (Japan). E-mail: [email protected]

Ligand-base Oxidation of Ethylbis(2-pyridylmethyl) amineruthenium(III) Complex Haruka Yonezawa, Sohei Fukui, Hirotaka Nagao, Department of Materials and Life Sciences, Sophia University, Tokyo (Japan). E-mail: [email protected]

Cobalt(III)-tren (tris(2-aminoethyl)amine) complexes with thiolate and/or thioether ligands have been investigated in view of their stereochemistry and ligand substitution reactions [1,2]. The stereochemistry of these Co(III) thiolato complexes has led us to many interesting results concerning the features of the coordinated sulfur atoms. Due to our interest in the stereochemistry and spectrochemical properties of the complexes, it was convenient to compare a tripod-like tetradentate tren and chain-like tetradentate trien (triethylenetetramine) ligands to fix the remaining two cis coordination sites in the Co(III) complexes. Although two geometrical p- (trans(Nprim,S))- and t(trans(Ntert,S))- isomers were possible for the [Co(bidentate-O,S) (tren)]-type complexes, only one isomer was selected formed by a reaction with tren and thiolate ligand such as 2-mercaptoacetic acid (H2ma) and 2-mercaptopropionic acid (H2mp). Now, five (a, two b(Nprim), and two b(Nsec)) geometrical isomers were separated and isolated of cobalt(III) complexes with trien and ma/mp ligands. Further, two types of cobalt(III)-silver(I) tri- and dodecanuclear complexes which have silver ion as some -S-Ag-Sbonds with ma/mp thiolate ligands were synthesized. It is clarified the stereochemical configuration of those isolated compounds by the X-ray crystal structural analysis, and measured UV-Vis, IR absorption, and NMR spectra and revealed spectroscopic characters. The spectral behaviors of the obtained dodecanuclear complexes were similar to those of the trinuclear cobalt-silver complexes, and it is thought that the influence to a spectroscopic character by addition of silver ion is so small.

We have been reported syntheses of ruthenium complexes having ethylbis(2-pyridylmethyl)amine (ebpma, Fig. 1(a)) as a supporting ligand by ligand-substitution reactions with the reduction reaction of fac-[RuIIICl3(ebpma)] [1]. We would like to report a ligandbase oxidation reaction on fac-[RuIIICl3(ebpma)] affording a bis(2pyridylcarbonyl)aminato (bpca, Fig. 1(b)) ligand and reactivity of the formed bis(2-pyridylcarbonyl)aminato-ruthenium complex. A cyclic voltammogram (CV) of fac-[RuIIICl3(ebpma)] in a CH3CN solution showed irreversible oxidation waves at 1.01 and 1.20 V. An oxidation reaction of fac-[RuIIICl3(ebpma)] by (NH4)2[CeIV(NO3)6] was carried out in acetonitrile under refluxing conditions for 5 hrs to give a brown complex showing reversible oxidation and reduction waves at 1.17 and -0.40 V in CV of the CH3CN solution and a strong absorption band in an IR spectrum at 1715 cm-1. This complex was identified as [RuIVCl2(NCCH3)-(bpca)]+, and changed to a new neutral complex in a H2O/HCl solution under refluxing conditions. This new complex is tentatively identified as [RuIVCl3(bpca)] from some measurement results. [RuIVCl2(NCCH3)(bpca)]+ and the new neutral complex were reduced by zinc powder to afford [RuII(NCCH3)3(bpca)]+ in CH3CN (Sheme 1). [RuIVCl2(NCCH3)(bpca)]+ decomposed in ethanol, acetone and chloroform under refluxing conditions except in acetonitrile and H2O/HCl. An oxidation reaction of fac­­-[RuIIICl3(ebpma)] by (NH4)2[CeIV(NO3)6] was carried out under Ar atmosphere to investigate the oxygen source of two carbonyl groups of bpca. A nitrosyl complex were formed with [RuIVCl2(NCCH3)(bpca)]+, and the nitrosyl ligand will be derived from nitrate ion in the oxidant. We will also report detailed reaction mechanisms of this ligand-oxidation reaction.

Fig 1. Structures of (a) ebpma and (b) bpca.

Scheme 1. Summary of reactions in this study. [1] T. Yonemura, K. Shibuya, K. Okamoto, T. Ama, H. Kawaguchi, and T. Yasui, Inorg. Chim. Acta, 1997, 260, 119-128. [2] T. Yonemura and K. Fujihara, Pacifichem 2010, 1292.

Keywords: Polynuclear complex, Cobalt(III)-Silver(I) complex, Thiolato complex

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[1] K. Matsuya, S. Fukui, Y. Hoshino, and H. Nagao, Dalton Trans., 7876(2009).

Keywords: oxidation reaction, tridentate ligand, aminato

Poster Sessions

Direct Observation of Cluster Core–to–ligand Charge Transfer Excited State in Octahedral Haxarhenium Complex Takashi Yoshimura,a,b Shoji Ishizaka,c Tatsuya Kashiwa,c Akitaka Ito,d Eri Sakuda,d Atsushi Shinohara,a Noboru Kitamura,c,d aDepartment of Chemistry, Graduate School of Science, Osaka University (Japan). b Radioisotope Research Center, Osaka University (Japan). cDepartment of Chemical Sciences and Engineering, Hokkaido University (Japan). d Department of Chemistry Faculty of Science, Hokkaido University (Japan). E-mail: [email protected] A new complex [Re6S8Cl5ppy]3- (ppy = 4–phenylpyridine) was synthesized and characterized to realize MLCT-type emission in an octahedral hexarhenium complex. (Bu4N)3[Re6S8Cl5ppy] was obtained by photoirradiation of a CH3CN solution of (Bu4N)4[Re6S8Cl6] in the presence of 10 equiv. of ppy at room temperature.[1] The complex [Re6S8Cl5ppy]3– showed the emission maximum wavelength (lem) at 690 nm in the crystalline phase. The lem values in the solutions shift to longer wavelength in the sequence of CH2Cl2 < CH3CN < C6H5CN < DMF. The emission lifetime (tem) of [Re6S8Cl5ppy]3– in the solution decreased in the order of CH2Cl2 > CH3CN > C6H5CN > DMF. The large solvent dependence of lem suggests that the excited state of the complex is the MLCT character. It is worth noting that the Fem (0.0089) and tem (0.33 ms) values of [Re6S8Cl5ppy]3– in CH3CN at 296 K are much larger and longer, respectively, than the relevant values of trans– and cis–[Re6S8Cl4L2]2– (L = bpy or pz, Fem = 0.0010 – 0.0017 and tem = 0.0013 – 0.0029 ms). [2] Direct evidence of the MLCT character in the excited state of [Re6S8Cl5ppy]3– has been obtained by nanosecond transient absorption spectroscopy. The transient absorption spectrum of [Re6S8Cl5ppy]3– in deaerated CH3CN observed in 0 – 100 ns after 266 nm laser pulse excitation. [Re6S8Cl5ppy]3– showed two absorption bands at 392 and 540 nm, The decay curve of the absorption band monitored at 400 nm was fitted by a single exponential function and the decay time constant was determined to be 0.32 ms, which was in good agreement with the tem value of [Re6S8Cl5ppy]3–: 0.33 ms. The results demonstrate explicitly that the electronic structure of the emissive excited state of [Re6S8Cl5ppy]3– is best characterized by the ppy– anion and, thus, the excited state of the complex is in {Re6S8} core–to–ppy ligand CT. This is the first demonstration of direct evidence of participation of the MLCT character in the excited state of the octahedral hexanuclear metal cluster complex. [1] T. Yoshimura, S. Ishizaka, T. Kashiwa, A. Ito, E. Sakuda, A. Shinohara, N. Kitamura, Inorg. Chem. 2011, 50, 9918-9920. [2] T. Yoshimura, C. Suo, K. Tsuge, S. Ishizaka, K. Nozaki, Y. Sasaki, N. Kitamura, A. Shinohara, Inorg. Chem., 2010, 49, 531-540.

Keywords: rhenium, photoluminescence, excited state properties

MS.C3.P.540 Novel Bimetallic Complexes Combining Dithiolene and Porphyrin Moieties Athanasios Zarkadoulas,a Christiana A. Mitsopoulou,a aInorganic Chemistry Laboratory, University of Athens, Panepistimiopolis Zografou 15771 Athens (Greece). E-mail: [email protected]

Porphyrins and metalloporphyrins also proved to be a fruitful field since their electronic properties rendered them efficient photosensitizers of photocatalysts for many applications, for example the photocatalytic splitting of water [4]. Additionally, porphyrins proved to be suitable fragments for functional supramolecular assemblies [5]. Motivated by the above, we decided to synthesize and characterize several meso-substituted porphyrins that comprise both the properties of the dithiolate complex and the porphyrin. Thus, the electronic interaction of the two aforementioned moieties is examined by altering the central metal of the porphyrin and / or the substituents as well as the metal on the dithiolene complexes. The new substances are candidate sensitizers for the photocatalytic splitting of water or the photosensitization of semiconductors (e.g. TiO2) in photoelectrochemical cells. [1] Progress in Inorganic Chemistry, Vol. 52, Dithiolene Chemistry, Ed. K. D. Karlin, Ed. E. I. Stiefel 2004 John Wiley & Sons, Inc. [2] C. Makedonas, C.A. Mitsopoulou, F. Lahoz, A.I. Balana, Inorg. Chem. 2003, 42, 8853-8865. [3] W. Paw, S.D. Cummings, M.A. Mansour, W.B. Connick, D.K. Geiger, R. Eisenberg, Coord. Chem. Rev. 1998, 171, 125-150. [4] V. Artero, M. ChavarotKerlidou, M. Fontecave, Angew. Chem. Int. Ed. 2011, 50, 7238-7266. [5] A.M. Brun, S.J. Atherton, A. Harriman, V. Heitz, J.P. Sauvage, J. Am. Chem. Soc. 1992, 114, 4632-4639.

Keywords: dithiolene, porphyrin, photosensitizer

MS.C3.P.541 H–bonding and Steric Effects on Phenolate and Phenoxyl Radical Complexes of Cu(II)

Galina M. Zats,a Himanshu Arora,a Ronit Lavi,a Dmitry Yufitb, and Laurent Benisvy*a aDepartment of Chemistry, Bar–Ilan University, Ramat Gan, 52 900, Israel.; Fax: 972–3–7384053; Tel: 972–3–7384599. bDepartment of Chemistry, University of Durham, South Road, Durham, UK, DH1 3LE. E–mail: galazats@ gmail.com

GAO[1] is a copper-containing enzyme that catalyses the oxidation of a primary alcohol to the corresponding aldehyde with concomitant reduction of O2 to H2O2. The enzyme is peculiar in using a single copper centre to achieve a two-electron oxidation. Its active site contains a catalytically active Cu(II)–tyrosyl radical moiety that has triggered current research interest in the preparation and studies of metal–phenoxyl radical complexes.[2] However, the local factors that modulate the redox properties of the Cu(II)–Tyr/Cu(II)–Tyr• redox couple are not yet fully understood. Herein, we present the synthesis and characterisation of new redox-active N,O-phenol-pyrazole proligands RLH, together with their corresponding bis-CuRL2 (1-3; see Scheme below).3 Whilst bis-CuHL­2 (1) is square planar with both the phenolate O-atoms H-bonded to the N-H pyrazole; the complexes bis-CuMeL2 (2) and bis-CuPrL2 (3) cannot establish H-bonding and are tetrahedrally distorted. All complexes 1-3 are reversibly oxidised to the corresponding stable Cu(II)-phenoxyl radical (1+- 3+) complexes, as indicated by their UV/vis and EPR data. The properties of the tetrahedrally distorted complexes 2 and 3 (and those of 2+ and 3+) are being compared to those of the square-planar H-bonded complex 1 and those of 1+. These studies have permitted H-bonding and steric effects on the redox, spectroscopic and chemical properties of Cu(II)phenolate and Cu(II)-phenoxyl radical species to be established.

Metal dithiolene complexes have introduced chemists to an intriguing area of research during the last five decades [1]. More specifically, mixed diimine-dithiolene complexes exhibit very interesting electronic properties arising from a Mixed-Metal-Ligandto-Ligand-CT (MMLL’CT) excited state [2,3] that can be effectively tuned by means of chemical modifications on the ligands.

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MS.C3.P.538

Poster Sessions which studied compounds and their saturated derivatives were used [2]. Presented data with no doubts show that chelatoaromaticity is an important effect that can clearly explain significant increase of the stabilization of some types of ligands. Acknowledgments. This research has been financed by the Polish Government (research project N N204 544839). ACK “Cyfronet” AGH is acknowledged for the computing time. [1] K.K. Zborowski, M. Solà, J. Poater, L.M. Proniewicz, J. Phys. Org. Chem., 2011, 24, 499-506. [2] K.K. Zborowski, L.M. Proniewicz, New Trends in Coordination, Bioinorganic and Applied Chemistry. M. Melnik, P. Segl’a, M. Tatarko, Ed., Press of Slovak University of Technology, Bratislava, 2011, 601612.

Keywords: chelatoaromaticity, chelates, stabilization

MS.C3.P.543

[1]. J. W. Whittaker, Chem. Rev., 2003, 103, 2347. [2] Fabrice T. Eur. J. Inorg. Chem. 2007, 17, 2365. [3] a. G. M. Zats, H. Arora, R. Lavi, D. Yufit, L. Benisvy Dalton Trans., 2012, 41, 47-49. b. G. M. Zats , H. Arora, R. Lavi, D. Yufit, L. Benisvy Dalton Trans., 2011, 40, 10889-10896.

Keywords: Galactose oxidase, Phenoxyl Radical, Copper

MS.C3.P.542 Chelatoaromatic Stabilization of Metal Complexes by Selected Ligands Krzysztof K. Zborowski,a Leonard M. Proniewicz,a,b aFaculty of Chemistry, Jagiellonian University in Kraków, Kraków, (Poland). bThe State Higher Vocational School, Tarnów (Poland). E-mail: zborowsk@ chemia.uj.edu.pl In this report we present our results of the study concerning the ability of representative ligands to induce the effect of a chelatoaromatic stabilization in metal complexes. In general, chelatoaromatic stabilization of chelate metal complexes is associated with the energy lowering due to proper structural changes of ligand aromaticity casued by chelatation. Thus, this phenomenon reinforce the stabilization of chelate metal complexes of ligands containing cyclic unsaturated rings in comparison to their saturated counterparts. Aluminium ion metal complexes of selected ligands (maltol, deferiprone, tropolone, 8-hydroxyquinoline, 1,4-benzoquinone, 2,2’-bipyridine) have been chosen as the objects of presented here study since properties of these complexes can be calculated on the relative high level of theory in comparison to other, heavier, metals. In addition, the importance of studies on understanding structure/ function (activity) of these metal complexes is growing. For example, changes in the soil acidity has resulted in the increasing bioavailability of aluminium ions that has an impact on quantity and quality of crops. Also, higher concentration of the aluminium ion in water can be dangerous. For example, aluminium-maltolate complex, one of the compounds investigated by us, is known to possess high neurotoxicity while maltol alone does not have such biochemical properties. Presented here calculations have been performed on the B3LYP/6-311++G** level of theory using the Gaussian ’09 package. Two applied approaches (used successfully by us previously in the case of metal complexes of hydroxypyrones) enabled the estimation of the chelatoaromatic stabilization energies in studied compounds. First of them has been the isomerization method [1] while the second have been based on calculations of enthalpies of synthesized metal complexes in

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Corroles and Corrins: macrocyclic effect on ligand binding properties of Co(III) Caitlin F. Zipp,a Helder M. Marques, a Joseph P. Michael, a Manuel A. Fernandes a and Christopher B. Perry,a aMolecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg, (South Africa). E-mail: [email protected] A realistic biomimetic of Vitamin B12 containing a corrole ring has been synthesized (Figure 1). The corrole, like the corrin of the cobalamins (Cbls, derivatives of vitamin B12), is a tetrapyrrolic macrocycle containing a pyrrole-pyrrole link. Thus the cavity size is similar to that of corrin; however, the fully conjugated system makes the corrole ring more electron rich. Comparison of this biomimetic model with Vitamin B12 has provided insights into how the corrin controls and modifies the properties of Co(III). The corrole biomimetic exists as a mixture of 5 and 6 co-ordinate species in solution, whose electronic properties have been rationalised by TD-DFT methods. Equilibrium constants for the replacement of axially coordinated H2O in the corrole biomimetic and in H2OCbl+ have been determined spectrophotometrically for a range of ligands including ethanolamine, cyanide, pyridine and N-methylimidazole in buffered 80:20 MeOH:H2O, and are compared and contrasted. The effect of the macrocycle on the kinetics of the ligand substitution of axial H2O are explored using CN¯ as a probe ligand.

Figure 1: Vitamin B12 biomimetic system containing a corrole ring

Keywords: Corrole, ligand substitution, Vitamin B12

MS.C3-P-544

MS.D1.P.545

Iridium Mediated N-H and C-H Bond Activation of N-(aryl) Pyrrole-2-aldimines Samaresh Bhattacharya,* Piyali Paul. Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700 032, India. E-Mail: [email protected]

Investigation of 7-Membered Organnometallic Compounds En Route to Autocatalytic Palladium Complexes with Antineoplastic Activity N.I. Barnard,a A.R. Roodt,a G.Steyl,a aInorganic Chemistry, Department of Chemistry, University of the Free State, Bloemfontein, 9300, South Africa. E-mail: [email protected]

Reaction of N-(4′-R-phenyl)pyrrole-2-aldimines (L-R, R = OCH3, CH3, H, Cl and NO2) with Ir(PPh3)3Cl in refluxing ethanol affords a group of yellow complexes (1-R), in which an imine-ligand (L-R) is coordinated to the metal center as a mono-anionic bidentate NN-donor (I) along with two triphenylphosphines, a chloride and a hydride. The hydride is trans to the coordinated pyrrole-nitrogen, while the chloride is trans to the imine-nitrogen, and the two triphenylphosphines are mutually trans. Similar reaction of N-(naphthyl)pyrrole-2-aldimine (L-nap) with Ir(PPh3)3Cl affords an organometallic complex, where the imine-ligand is coordinated to the metal center, via C-H activation of the naphthyl ring at the 8-position, as a di-anionic tridentate NNCdonor (II), along with two triphenylphosphines and a hydride [1]. Reaction of N-(2′,6′-dimethylphenyl)pyrrole-2-aldimine (L-Me2) with Ir(PPh3)3Cl in refluxing tolune affords affords two organometallic complexes (3 and 4), where the imine-ligand is coordinated to the metal center, via a methyl C-H activation, as a di-anionic tridentate NNC-donor (III), along with two triphenylphosphines and a hydride (in 3) or a chloride (in 4) [2]. Structures of complexes 1-OCH3, 2, 3 and 4 have been determined by X-ray crystallography. All the complexes are diamagnetic, and show characteristic 1H NMR signals and intense transitions in the visible region.

[1] P. Paul, S. Bhattacharya, J. Organomet. Chem., 2012, 713, 72-79. [2] P. Paul, S. Bhattacharya, unpublished results.

Keywords: N-(aryl)pyrrole-2-aldimine, iridium, N-H and C-H bond activation

Chemical-, pharmacological-, and clinical-research on anticancer coordination complexes has yielded remarkable anticancer agents such as cisplatin, carboplatin, and oxaliplatin. The significant similarity between the coordination chemistry of palladium(II) and platinum(II) compounds has advocated studies of Pd(II) complexes as antitumor drugs[1],[2]. In general, the strategies that have been applied to design these agents were on the window of reactivity usually employed for the potential platinum antitumor drugs. The hydrolysis in palladium complexes is too rapid: 105 times faster than for their corresponding platinum analogues. It dissociates readily in solution leading to very reactive species that are unable to reach their pharmacological targets. The considerably higher activity of palladium complexes implies that if an antitumor palladium drug is to be developed, it must somehow be stabilized by a strongly coordinated ligand and a suitable leaving group. If this group is reasonably non labile, the drug can maintain its structural integrity in vivo long enough [3]. The antitumor activities of tropolone and derivatives thereof are well documented. Mono and bis-tropolonato species have been synthesized and evaluated. With the potency of bistropolone approximately 200 times of that of monotropolone[4]. The palladium centered tropolonato complexes in this study display autocatalytic activity – autocatalysis of the compound itself to form new substrates for anti-cancer pharmaceuticals.

[1] R. D. Graham and D. R. Williams, J. Inorg. Nuclear Chem., 1979, 41, 12451259. [2] T. Rau and R. van Eldik, Metal Ions In Biological Systems; H. Sigel, A Sigel, Eds., Marcel Dekker: New York, 1996, 31, 339-378. [3] A. S. AbuSurrah,H. H. Al-Sa’doni, M. Y. Abdalla, Cancer Therapy, 2008, 6, 1-10. [4] M. Yamato, J. Ando, K. Sakaki, K. Hashigaki, Y. Wataya, S. Tsukagoshi,T. Tashiro and T. Tsuruo J. Med. Chem. 1992, 35,267-273 and references therein.[5] G. Steyl, A. Roodt Tropolone , Models, Mysteries, and Magic of Molecules, J.C.A. Boeyens, J.F. Ogilvie, Eds., Springer: AA Dordrecht, The Netherlands 2008, 325-340.

Keywords: Palladium, tropolone, pharmaceuticals

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Poster Sessions

Poster Sessions MS.D1.P.547 Protocols for Studying Bismuth Complexation Toward Medicinal Applications Caren Billing,a I. Cukrowski.b aMolecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg (South Africa), bDepartment of Chemistry, University of Pretoria, Pretoria (South Africa). E-mail: [email protected] The use of bismuth in medicinal applications is limited despite the many promising indications of its effectiveness in treatments of a large number of ailments. This is predominantly due to the lack of understanding of thermodynamic and kinetic aspects of bismuth chemistry, as well as its interaction with biologically important molecules. This, in turn, is owing to difficulties in studying bismuth coordination chemistry. Bismuth undergoes hydrolysis from below pH 1 in aqueous environments and forms precipitates around pH 2 already, thus has to be studied from low pH. This rules out the use of the most widely used technique to determine stability constants, namely glass electrode potentiometry. Complex formation has previously been studied by polarography where potential shifts and current changes are monitored while changing the solution conditions (by increasing the pH or ligand concentration). This data is then used to determine the solution species and evaluate their stability constants. The benefits of employing polarography in these studies are that low bismuth concentrations (of the order of mmol L-1) can be used to postpone precipitation and it can be used across the pH range. Employing this technique is not without its own challenges. The diffusion junction potential, which is due to the extremely high mobility of hydrogen ions in solution, becomes significant below about pH 2 and it changes with pH. In order to interpret any polarographic data below pH 2 it is necessary to quantify the potential shift due to the junction potential - a value that cannot be directly measured. The reduction potential of uncomplexed Bi(III) is also a critical parameter required in the evaluation of the formation constants by polarography, but it cannot be directly measured due to Bi(III) being hydrolysed. Adsorption of the ligand on the mercury electrode surface or the reduction of the ligand itself can also interfere with polarographic measurements. Slow electron transfer to the complexed Bi(III) could result in quasi-reversible or irreversible reduction signals, whereas the potential and current values for a reversible process are required for analysis. Results for various Bi(III)-ligand systems will be presented together with ways in which some of the above challenges were addressed.

resonance imaging, MRI), others by high sensitivity but low macroscopic resolution (optical imaging). Luminescent/MRI bimodal imaging offers the advantage of combining both the sensitivity and the resolution. Lanthanide complexes are particularly adapted to design such bimodal agents, as they have a similar chemical behaviour while their magnetic and optical properties are specific of each ion. Gd3+ complexes are well-known as efficient contrast agents, and several Ln3+ cations emit in the visible or in the near infrared (NIR) range. NIR imaging is more compatible with biological applications as low scattering of NIR photons allows for a better image resolution, the lack of NIR luminescence in biological systems makes the detection highly sensitive, and NIR photons can cross significant tissue depths for noninvasive imaging. We have recently developed pyridine-based bimodal agents that are active both as MRI and NIR luminescent probes (cf scheme). The bishydrated complexes are found to be thermodynamically and kinetically stable, and the ligands show a significant selectivity for Ln3+ over endogenous cations such as Zn2+, Ca2+ and Cu2+ as shown by pH-potentiometric measurements. The chelates do not form ternary complexes with endogenous donors which does not limit relaxivity in biological media. Photophysical characterizations have also been performed, and all the complexes give rise to NIR emission with remarkable quantum yields.[2] We have shown for the first time that even bishydrated complexes can have a quantum yield in the same range as those of the most optimized chelates so far reported. In order to shift the excitation energy towards lower values, more adapted to biological applications, the pyridine was successfully modified either by appending a triazole moiety (4-5) [3] or replaced by quinoline derivatives (6-8).[4] These pyridinic ligands constitute a highly versatile platform for the simultaneous optimisation of both MRI and optical properties. In the search of new chromophores, we have also developed an amphiphilic system (3) that forms micelles in solution and that can be used for chromophore screening. The hydrophobic chromophore was included inside a micelle formed by Ln3+ complexes and we showed that energy transfer can occur between the two entities not covalently linked.[5]

Keywords: Bi(III) complexation, acidic conditions, polarography

MS.D1.P.549 Pyridine-Based Lanthanide Complexes Combining MRI and NIR Luminescence Activities Célia S. Bonnet,a Fabien Caillé,a,b Frédéric Buron,b Franck Suzenet,b Stéphane Petoud,a Eva Toth,a aCentre de Biophysique Moléculaire, CNRS, Orléans, (France). bInstitut de Chimie Organique et Analytique, University of Orléans, Orléans (France). E-mail: [email protected] Imaging has become an indispensable tool in medical practice and biomedical research. In the past three decades there has been a huge increase in the number of imaging technologies and their applications. Among the state-of-the art bioimaging modalities, some are characterized by high resolution but low sensitivity (magnetic

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[1] L. Pellegatti, J. Zhang, B. Drahos, S. Villette, F. Suzenet, G. Guillaumet, S. Petoud, E. Toth, Chem. Commun., 2008, 6591. [2] C.S. Bonnet, F. Buron, F. Caillé, C.M. Shade, B. Drahos, L. Pellegatti, J. Zhang, S. Villette, L. Helm, C. Pichon, F. Suzenet, S. Petoud, E. Toth, Chem. Eur. J., 2012, 18, 1419. [3] F. Caillé, C.S. Bonnet, F. Buron, S. Villette, L. Helm, S. Petoud, F. Suzenet, E. Toth, Inorg. Chem.., 2012, 51, 2522. [4] ] C.S. Bonnet, L. Pellegatti, F. Buron, C.M. Shade, S. Villette, V. Kubicek, G. Guillaumet, F. Suzenet, S. Petoud, E. Toth, Chem. Commun., 2010, 124.

Keywords: Luminescence, Lanthanide

Magnetic

Resonance

Imaging,

MS.D1.P.550 Cellular Response to an Antitumor Platinum(II) Complex of CDK Inhibitor Bohemine Viktor Brabec,a,b Barbora Liskova,b Lenka Zerzankova,b Olga Novakova,b Zdenek Travnicek,c aDepartment of Biophysics, Faculty of Science, Palacky University, Olomouc (Czech Republic). bInstitute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Brno (Czech Republic). cDepartment of Inorganic Chemistry, Faculty of Science, Palacky University, Olomouc (Czech Republic). E-mail: [email protected] One of the strategies used to improve the chemotherapy of existing drugs is to synthesize novel drugs with improved therapeutic effect derived from their ability to target, aside from the original target, another molecular target. Such therapy has the potential to increase the total cytotoxicity due to the additive or synergetic effects, thereby decreasing the amount of original (existing) drug required and consequently reducing side effects on healthy, noncancerous tissues to broaden the spectrum of sensitive human tumors and/or to overcome resistance to existing drugs. The cellular and molecular pharmacology of the new class of anticancer drugs, in which the cyclin-dependent kinase (CDK) inhibitor bohemine (2-(3-hydroxypropylamino)-6-benzylamino-9isopropylpurine) and its analogues are coordinated to Pt(II) to form cisplatin derivatives, was investigated. The results revealed the unique anticancer profile of a cisplatin-derived platinum(II) dichlorido complex involving N(7)-coordinated bohemine (C1). Although the IC50 values (compound concentrations that produce 50% of cell growth inhibition) were ∼6-fold higher for C1 than for cisplatin in cisplatinsensitive tumor cells, the tumor cells in which C1 was also active are those which acquired resistance to cisplatin. In addition, among the novel conjugates of bohemine and its analogues with cisplatin, marked selectivity of C1 for tumor cells relative to the nontumorigenic, normal cells was observed. However, coordination of bohemine to platinum in C1 considerably reduced one of the dual functionalities anticipated to be effective after C1 reaches the nucleus. Further studies performed in the cells with wt p53 status show differences between cisplatin and C1 at the level of cell cycle regulation. Impedance-based real-time monitoring of the effects of C1 and cisplatin on cell growth supported the thesis that critical differences exist in the rate and mechanisms of cell kill caused by the two agents and that C1 was a more potent inducer of apoptosis and/or necrosis than cisplatin. The results also showed that the distinct differences in cell killing observed for C1 and cisplatin might be associated with processes at the DNA level. The DNA binding experiments carried out in a cell-free medium demonstrated that modification reactions resulting in the irreversible coordination of C1 to DNA were slower than that of cisplatin. Transcription mapping experiments and determination of interstrand cross-linking efficiency of C1 suggested that several aspects of DNA binding mode of C1 and cisplatin were similar. It was concluded that C1 remains a promising prototype of compounds for the generation of novel drug candidates with cytotoxicity profiles different from those of the platinum drugs currently in use [1]. [1] B. Liskova, L. Zerzankova, O. Novakova, Z. Travnicek, V. Brabec, Chem. Res. Toxicol., 2012, 25, 500-509.

Keywords: anticancer platinum, cell cycle arrest, DNA damage

MS.D1.P.551 Characterization and biological studies of a novel Pd(II) complex with L-alliin Pedro P. Corbi,a Camilla Abbehausen,a Suelen F. Sucena,a Marcelo Lancellotti,b André L. B. Formiga,a aInstitute of Chemistry, University

of Campinas - UNICAMP, 6154, 13083-970 Campinas, SP, (Brazil). b Institute of Biology, University of Campinas-UNICAMP, Campinas, SP, (Brazil). E-mail: [email protected] Metal-based compounds have been considered as therapeutic agents for centuries. Experiments with metallopharmaceutical compounds were first performed based on the knowledge of the toxic properties of metal ions in biological systems. One of the most largely used metalbased drugs is cisplatin, or cis-diamminedichloridoplatinum(II), which has been used for the treatment of several human cancers, particularly testicular, ovarian, bladder, lung, head and neck cancer [1]. Specifically, due to the growth of multi-resistant bacterial strains, syntheses of new antibacterial agents of silver(I), gold(I) and also platinum(II) and palladium(II) for the treatment of infectious diseases have been reported. Here, we report the synthesis, spectroscopic characterization and antibacterial assays of a novel Pd(II) complex with alliin (S-allyl-L-cysteine sulfoxide), a sulfur-containing amino acid found in garlic and onion bulbs, and precursor of natural antibiotics such as allicin and other polysulfides [2]. The Pd(II)-alliin complex was synthesized by the reaction of an aqueous solution containing 0.50 x 10-3 mol of lithium tetrachloropalladate(II), Li2[PdCl4] in a methanolic solution (4.0 mL) with 1.0 x 10-3 mol of L-alliin (10.0 mL) in alkaline medium. Synthesis was performed at room temperature. After 2 hours of constant stirring, the pale yellowish solid obtained was vacuum filtered, washed with cold water and dried over P4O10. Anal. Calc. for [Pd(C6H11NO3S)­ ]×2H2O (%): C, 29.1; H, 4.90; N, 5.66. Found (%): C, 28.4; H, 4.54; 2 N, 5.62. Infrared (IR), electrospray ionization mass spectrometry (ESIMS), and 1H, 13C and [1H–15N] nuclear magnetic resonance (NMR) spectroscopic measurements indicate coordination of alliin to Pd(II) in a bidentate form through the nitrogen atom of NH2 group and one of the oxygen atoms of COO- group. Density functional theory (DFT) studies were used to optimize the structure of the Pd(II)-alliin complex. The proposed structure based on the experimental data was confirmed as a minimum of the potential energy surface (PES) with the calculation of the hessians, showing no imaginary frequencies. An antibiogram assay was carried out in order to evaluate the antibacterial activities of the Pd(II)-alliin complex. Bacterial susceptibilities were evaluated by diffusion method and confirmed by determination of minimal inhibitory concentration (MIC). The complex showed antibacterial activity against Staphylococcus aureus (Gram-positive), Escherichia coli and Pseudomonas aeruginosa (Gram-negative) bacterial cells, with MIC values in the range 125-500 mg mL-1. [1] D. Lebwohl, R. Canetta. Eur. J. Cancer, 1998, 34, 1522-1534. [2] C.P. Siegers, B. Steffen, A. Robke, R. Pentz. Phytomedicine, 1999, 6, 7-11. Financial support: FAPESP and CNPq (Brazilian Agencies)

Keywords: palladium(II), alliin, antibacterial agent

MS.D1.P.552 Pharmacological Properties of Oxindolimine-Metal Complexes Ana M. Da Costa Ferreira,a Mauricio Cavicchioli, a Marcela Bach Prieto,a Carla C. de Oliveira,a Patrizia Civitareale,b Maria Rosa Ciriolo.b aInstitute of Chemistry, University of São Paulo, São Paulo (Brazil). bDepartment of Biology, University Tor Vergata of Rome, Rome (Italy). E-mail: [email protected] Metal complexes with Schiff bases derived from isatin, a metabolite of tryptophan, are focused in this work. Ligands with different structures were synthesized, based on oxindole compounds already tested as efficient inhibitors of kinases, enzymes involved in the

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Poster Sessions regulation of cell cycle. Those oxindolimine ligands were metallated with copper(II) or zinc(II) ions, in order to verify the influence of different factors in their biological activity. Results by diverse methodologies (CD, EPR, fluorescence, gel electrophoresis) indicated that these complexes have DNA, and mitochondria as main targets, causing double strand cleavage and acting as uncoupling agents [1, 2]. The metal ion supplies charge for the oxindolimine ligands, giving rise to delocalized lipophilic cationic species that are able to enter the cell and damage crucial organelles. Binding to DNA occur at minor or major groove, depending on the ligand, with binding constants in the range 3 to 9×102 M−1 when using plasmidial DNA. Herein, the probable mechanism of action of such complexes will be discussed. In the case of copper(II) complexes, an oxidative mechanism seems to be predominant, occurring by generation of reactive oxygen species (ROS) and being modulated by ligand-depending properties, mainly lipophilicity, structural characteristics, thermodynamic stability constant, and redox potential. Analogous zinc(II) complexes also exhibit activity, although in lower extension, probably due exchange of the metal by copper ions inside the cells, in a time dependent process. These complexes can induce selective apoptosis of different tumor cells (neuroblastomas, melanomas, sarcomas) mostly activating AMPand MAP-Kinases that are sensors of energetic impairment in cells [3,4]. All the obtained data indicate significant possibilities of those compounds being used as pharmacological agents [5]. Acknowledgements: FAPESP, CNPq/INCT-Redoxoma.

[1] V.C. Silveira et al., J. Inorg. Biochem. 2011, 105, 1692–1703. [2] V.C. Silveira et al., J. Inorg. Biochem. 2008, 102, 1090-1103. [3] G. Filomeni et al., Carcinogenesis 2009, 30, 1115-1124. [4] G. Filomeni et al., Biochem. J. 2011, 437, 443–453. [5] Ferreira et al., Patent BPXXDX BR 2006000985 A 20071127.

Keywords: oxindolimine-metal complexes, antitumor activity, medicinal chemistry

MS.D1.P.553 Computer-Aided Design, Synthesis, and Biological Evaluation of Novel 2-Substituted Aminomethylenepyrimidine-2,4,6-Triones as H1 Antihistaminic Agents Dr. Rasha Y. Elbayaa, Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Alexandria, Egypt.Tel.: 002-034871317, Fax: 002-03-4873-273. E-mail: [email protected] As a part of a research project pertaining to the synthesis of novel candidates as nonsedating, nonclassic H1 histaminergic (H1) blockers with low toxicity profiles, some new 2-substituted aminomethylenepyrimidine-2,4,6-triones were designed based on the H1 histaminic receptor pharmacophore model. The interactions between the designed compounds and the H1 receptor were studied using molecular docking on the homology model of H1 receptor. The designed compounds were synthesized and biologically evaluated for H1-blocking activity; using isolated segments from guinea pig ileum.

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Some compounds exhibited comparable activities to acrivastine as reference nonsedating drug. The C log P of designed compounds revealed lower values in relevance to acrivastine which might indicate decreased tendency for crossing the blood brain barrier. Keywords: Synthesis, Docking, Pharmacophore model

MS.D1.P.554 Effect of Manganese(III) Complexes on the Viability Of Irradiated Cells Breno Espósito,a Tatiana Pereira,a Gisele da Silva,a Fábio Forti,a a Instituto de Química, Universidade de São Paulo, São Paulo (Brazil). E-mail: [email protected] Manganese (Mn) is an essential trace element, however there is considerable concern regarding its neurological effects when in excess, which gives rise to a condition termed manganism, characterized by Parkinson-like symptoms. On the other hand, several Mn(III) superoxide-dismutase (SOD)-like mimetics have been proposed in antioxidant therapies [1]. Most evaluations of manganese toxicity use poorly defined Mn(II) species, although Mn(III) is known to accumulate preferentially in the brain [2]. Therefore, in this work we asked whether Mn(III) species may be able to rescue the viability of UV-stressed HeLa cells, and the combination effect of either ascorbate or para-aminosalicylate (PAS) in this treatment. Mn(III) derivatives of citrate, pyrophosphate and salen (respectively, MnCit, MnPPi and EUK8) were prepared and characterized by published methods. Their EC50 to HeLa cells (15, 30 and > 200 mM for MnCit, MnPPi and EUK8, respectively) were found to be inversely correlated to their octanol-water partition coefficients. HeLa cells were irradiated with UVA (365 nm, dose 50 J/m2) or UVB (302 nm, dose 80 J/m2), and then exposed to each Mn derivative at its EC50 for 24 h, in the presence or absence of either ascorbate (40 mM) or PAS (200 mM). All the experiments were conducted in triplicate and repeated at least twice. Control cells were not irradiated. The effect of UVB irradiation was too severe and the result of its combination with any of the treatments was not significantly different from the UVB controls. However, we found that MnPPi and MnCit displayed a negative synergistic effect with UVA over HeLa cells (the combination of irradiation and Mn treatment diminished cell viability). SOD mimic EUK8 did not restore the viability of irradiated cells. Surprisingly, ascorbate co-treatment reduced even further cell viability even of non-irradiated cells (MnCit, EUK8), which indicates that ascorbate may have facilitated Mn reduction and subsequent internalization into the cell. PAS chelator did not restore cell viability, probably due to the rather slow complexation with Mn(III) derivatives. Our results suggest that different species of Mn(III) – even those proposed as antioxidants – will have different toxicities over sensitive cells. Also, stressed cells may be especially prone to metal-induced toxicity. Endogenous cofactors able to induce redox cycling of metals and/or their assimilation (ascorbate) may worsen the situation. [1] S. Amaral, B. P. Espósito, BioMetals, 2008, 21, 425-432. [2] M. Aschner et al, Toxicol. Appl. Pharm., 2007, 221, 131-147.

Keywords: manganese, ascorbate, para-aminosalicylate

MS.D1.P.555 Ruthenium-based Complexes with 5-methyl-1,2,4-triazolo[1,5-a] Pyrimidin-7(4H)-one Marzena Fandzloch,a Iwona Łakomska,a Andrzej Wojtczaka, aFaculty

of Chemistry, Nicolaus Copernicus University, Toruń (Poland). E-mail: [email protected] Ruthenium compounds are arguably the best candidates to add to platinum-based drugs in cancer therapy. Their ability to mimic the behaviour of iron, by binding to proteins in the plasma, makes them ideally suited to metal-based drug design. Two particularly promising inorganic ruthenium(III) compounds, [ImH][trans-Ru(DMSO)(Im) Cl4] (NAMI-A, Im = imidazole) and [IndH][trans-Ru(Ind)2Cl4] (KP1019, Ind = indazole), are undergoing phase II clinical trials [1], [2], [3], [4]. Furthermore, also ruthenium(II) complexes are rapidly becoming a central focus for the development of new metal-based anticancer treatments [5]. Following this research lines novel ruthenium(II) and ruthenium(III) coordination compounds with 5-methyl-1,2,4-triazolo[1,5-a] pyrimidin-7(4H)-one (HmtpO), have been synthesized. New complexes of formulas [RuCl2(dmso)3(HmtpO)] and [RuCl4(HmtpO) (H2mtpO)]·2CH3OH have been characterized by IR, UV-Vis, MS, X-ray, NMR study (for Ru(II) complex) or magnetic and EPR studies (for paramagnetic Ru(III) complex). In order to determine composition of coordination sphere and structure of the novel ruthenium(II) complex with HmtpO, 1H, 13C and 15 N NMR spectra were measured. The 1H NMR spectra exhibit singlets of H(2) and H(6) in range 6.00-8.69 ppm. Both characteristic ligand signals have been deshielded after coordination. To determine which of the heterocyclic nitrogen atoms participate in formation of rutheniumtriazolopyrimidine bond 15N-1H HETCOR NMR spectra were measured. The strongest shielding effect on N(3) atom unambiguously indicate that complexation occurs via this nitrogen atom. Crystal structure of [RuCl4(HmtpO)(H2mtpO)]·2CH3OH indicates the octahedral geometry with two axial N(3) bonded HmtpO in headto-head orientation. Cytotoxic in vitro studies against two human tumour cell lines (A549 - non-small cell lung carcinoma, T47D - breast carcinoma) and one mice fibroblasts Balb/3t3 were also been evaluated. Using the same nonleaving ligand (HmtpO) for two different types of ruthenium complexes, influence of leaving ligands on cytotoxic parameters will be discussed. Acknowledgement Financial support from National Science Centre (NCN); Grant No DEC-2011/01/N/ST5/02535. [1] G. S. Smith, B. Therrien, Dalton Trans., 2011, 40, 10793-10800. [2] E. M. Nagy, C. Nardon, L. Giovagnini, L. Marchio, A. Trevisan, D. Fregona, Dalton Trans., 2011, 40, 11885-11895. [3] T. Gianferrara, I. Bratsos, E. Alessio, Dalton Trans., 2009, 38, 7588-7598. [4] M. A. Jakupec, M. Galanski, V. B. Arion, C. G. Hartinger, B. H. Keppler, Dalton Trans., 2008, 2, 183-194. [5] V. Mahalingam, N. Chitrapriya a, F. R. Fronczek, K. Natarajan, Polyhedron, 2008, 27, 27432750.

Keywords: ruthenium complex, N-donor ligand, cytotoxicity in vitro

MS.D1.P.556 Triazacyclononane Phosphinic Acids (TRAP) as Ligands for 68Ga Pharmaceuticals Petr Hermann,a Jakub Šimeček,a,b Johannes Notnib aDepartment of Inorganic Chemistry, Universita Karlova (Charles University), Prague (Czech Republic). bPharmaceutical Radiochemistry, Technische Universität München, Garching (Germany). E-mail: petrh@natur. cuni.cz Gallium-68 radiopharmaceuticals are the most interesting alternatives to those based on 18-F. 68-Ga is conveniently produced in commercial 68-Ge/68-Ga generator unlike cyclotron-produced 18-

F. As metal isotope, 68-Ga must be tightly complexed by a suitable ligand. Macrocyclic ligands are the most suitable ones as their Ga3+ complexes are thermodynamically stable and kinetically inert. Till now, 68-Ga radiopharmaceuticals have been based on DOTA and NOTA (Figure) skeletons but these ligands exhibit non-optimal labelling properties (high excess of the ligand, long heating etc.). 1,4,9-TRiAzacyclononane Phosphinic acids (TRAP ligands, Figure) have been suggested as ligands for the fast and efficient 68-Ga incorporation.[1] Due to low basicity of the phosphinic acid moieties as well as the ring nitrogen atoms, full complexation is possible in highly acidic solutions (down to pH 1, i.e. pH of the neat generator eluate). Presence of weakly complexing atoms outside the ligand cage (oxygen atoms e.g. in TRAP-Pr or TRAP-OH, Figure) facilitates metal isotope incorporation in highly diluted solutions (non-carrier-added conditions) due to increasing effective metal ion concentration close to the macrocyclic cage.[2] As very low excess of the ligands/conjugates is necessary for complexation, very high specific activity can be obtained.[2] Unusual stable out-of-cage complexes were observed in the Ga–TRAP-OH system where deprotonated P–CH2O– groups participate in Ga3+ coordination.[3] The efficiency of 68-Ga labelling is also govern by selectivity of the TRAP ligands for Ga3+ over the most common impurities, Zn2+ and Fe3+ ions.[4] The data on these and similar ligands will be presented together with some in vitro / in vivo results.

[1] J. Notni, P. Hermann, J. Havlíčková, J. Kotek, V. Kubíček, J. Plutnar, N. Loktionova, P. J. Riss, F. Rösch, I. Lukeš, Chem. Eur. J. 2010, 16, 7174–7185. [2] J. Notni, J. Šimeček, P. Hermann, K. Pohle, H.-J. Wester, Chem. Eur. J. 2011, 17, 14718–14722. [3] J. Šimeček, M. Schulz, J. Notni, J. Plutnar, V. Kubíček, J. Havlíčková, P. Hermann, Inorg. Chem. 2012, 51, 577–590. [4] J. Šimeček, J. Notni, O. Zemek, P. Hermann, H.-J.Wester, Chem. Eur. J. 2012, submitted.

Keywords: macrocycles, gallium, phosphinates

MS.D1.P.557 SOD and Cytotoxic Activities of Cu(II) and VO(II) Complexes Incoroprating Wtaer Soluble Benzimidazole Ligand Mohamed M. Ibrahim*, Gaber A. M. Mersal, and Samir A. El-Shazly, Department of Chemistry, Faculty of Science, Taif University, Taif, 888, (KSA). E-mail: [email protected] It is known that cancer cells have less than normal SOD activity and the treatment with bovine native Cu-SOD decreased the growth of several solid tumors [1]. Furthermore, low molecular weight compounds with superoxide dismutase mimetic activity have potential use as antioxidant pharmaceuticals in the treatment or prevention of several diseases related with the overproduction of an undesired O2-. Although the mechanistic aspects of O•2- dismutation by metal ions and complexes is very limited, it has been established that the

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Poster Sessions metal ion must be capable of being both oxidized and reduced by superoxide. As a part of a research project devoted to the synthesis and characterization of copper(II) complexes with pharmacological activity [2], we have now prepared a new water soluble ligand, namely bis(2-benzimidazolylmethyl-6-sulfonte)amine L2 based on the water insoluble bis(2-benzimidazolylmethyl)amine L1 [3]. The ligand L2 was used for the synthesis of zinc(II), copper(II), and oxidovanadium(IV) complexes [L2M(H2O)2] (M = Zn2+ 1, Cu2+ 2, and VO2+ 3). The ligand and its metal complexes were characterized by elemental analysis, IR, 1H-13C NMR, UV–vis, and ESR spectroscopy, as well as electrochemical measurements, including cyclic voltammetry and electrical molar conductivity, and magnetic moment measurements. A square pyramidal geometry is proposed for all complexes. The superoxide dismutase-like activity of complexes 1-3 has been investigated using the nitrobluetetrazolium/superoxide reduction assay. The results show that both copper(II) 2 and vanadyl(II) complex 3 possess the capability to dismutase the superoxide anion generated in the xanthine/xanthine oxidase system. The catalytic efficiency of O-2 scavenging by complexes depends on the nature of the metal ion. A probable mechanistic implications for the catalytic dismutation of O-2 by vanadyl(II) complex 3 is proposed. The water soluble complexes 2 and 3 were assessed for their cancer chemotherapeutic potential towards colon cancer cell line (Caco-2) and showed that these complexes have the potential to act as an effective anticancer drug with IC50 values of 4.0 and 2.5 mM for complexes 2 and 3, respectively. [1] L. W. Oberly, G. R. Buettner, Cancer Res. 1979, 39, 1149. [2] M. M. Ibrahim, A. M. Ramadan, Mersal G. A. M., El-Shazly S. A., J. Mol. Struct. 2011, 998, 998, 1-10. [3] K. Kazuhiko, K. Nakata, M. M. Ibrahim, Chem. Lett. 2000, 296-297.

Keywords: Benzimidazole-containing ligand, oxidovanadium(IV) complexes, SOD and antitumor activities

MS.D1.P.558 DNA-Binding Properties and Nuclease Activities of Mixed-Ligand Ruthenium(II) Complexes Capable of Hydrogen-Bonding Naho Iizuka, Misaki Nakai, Yasuo Nakabayashi, Faculty of Chemistry, Materials and Bioengineering, Kansai University, 3-3-35, Yamatecho, Suita, Osaka 564-8680, Japan. E-mail: [email protected] Metal complexes are ideal templates for the design of DNAinteractive systems. In addition to a variety of binding modes, metal complexes that reversibly bind to DNA are becoming of increasing interest. In recent years, ruthenium(II)-polypyridine complexes have been studied extensively as chemotherapeutic agents due to their strong DNA-binding and rich photochemical properties. In this study, the mixed-ligand ruthenium(II)-2,2’-bipyridine complexes containing 1,6-diaminohexane (hx, hydrogen-bonding ligand) and 1-aminohexane (ha, nonhydrogen-bonding ligand) have been synthesized (Scheme 1) and characterized by 1H NMR, UV-vis, and cyclic voltammetry. The interactions of these complexes with CT-DNA have been investigated by using spectroscopic (CD and fluorescence) and agarose gel electrophoretic techniques. The CD spectra of CT-DNA in the presence of 1 and 3 showed significant decreases of the positive and negative Cotton effects compared to those in the presence of 2 and 4. This result indicates that 1 and 3 are able to bind DNA by hydrogen bonding followed by DNA conformational changes. In addition, CD spectroscopy revealed that 1 and 3 exhibited sequence selectivity by binding more strongly to AT than GC sequence. Fluorescence intensity decreased on the addition of all complexes to the DNA-bonded ethidium bromide (EtBr). The representative fluorescence spectral changes in the presence of 3 and 4 are shown in Fig. 1. The apparent binding constants (Kapp) estimated

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from relevant fluorescence quenching data were 3 > 1 > 2 > 4. The photo- and oxidative cleavages of pBR322 DNA were carried out by agarose gel electrophoresis, suggesting that the DNA cleavage efficiency shown by the ruthenium(II) complexes capable of hydrogenbonding is higher than those of nonhydrogen-bonding, 1 > 2 and 3 > 4.

Scheme 1. Syntheses of complexes 1 - 4.

Fig. 1. Fluorescence spectral changes of 10 mM EtBr containing 100 mM CT-DNA with increased addition of 3 (left) and 4 (right) in 5 mM Tris–HCl buffer at pH 7.5. lex = 470 nm. Keywords: Ruthenium(II) Complexes, Hydrogen-Bonding, DNA

MS.D1.P.559 Structure-based Inhibitor Design of Diketo Acid Derivatives Targeting Influenza Virus Metalloenzyme RNA Polymerase Yoshinobu Ishikawa,a Atsushi Ugai,a Seiji Miyazaki,a Noriyuki Ishigaki,a Kimihide Ozaki,a Hideshi Yokoyama,a Satoshi Fujii,a aSchool of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, (Japan). E-mail: [email protected] Influenza is a yearly seasonal threat and a cause of mortality. Although neuraminidase inhibitors are used for medication, drug resistance has gradually emerged. Thus, the development of effective anti-influenza drugs targeting different constituent proteins of the virus is urgently desired. The influenza virus is a segmented negative-stranded RNA virus. The synthesis of influenza virus mRNA occurs in the nuclei of infected cells, and is catalyzed by a viral RNA polymerase consisting of the three subunits, PA, PB1, and PB2. This RNA-dependent enzyme possesses endonuclease and RNA transcriptase activities, and is hence essential for viral replication. Studies on the crystallography of the PA subunit have revealed that PAN, the N-terminal domain of PA, contains one Mg ion or two Mn ions in the endonuclease active site [1,2]. The endonuclease activity of the PAN subunit with two Mn ions is inhibited by the diketo acid derivative 1 [2]. This suggests that it should chelate those metals and inhibit the endonuclease activity. Tomassini and co-workers at Merck reported that diketo acid derivatives 1 and 7 are effective inhibitors of influenza viral transcription [3,4]. Given that the action is due to the inhibition of the endonuclease activity of the PAN subunit, the metalloenzyme is currently regarded as a promising target for anti-influenza virus agents. In this light, we carried out molecular docking to predict the binding modes of anti-influenza diketo acid inhibitors in the active site of the PAN subunit of the metalloenzyme RNA polymerase. The calculations suggested that the dianionic forms of the diketo acids should chelate the dinuclear manganese center as dinucleating ligands and sequester it [5]. In addition, the critical residue for the lead optimization of 1 and 7 was likely to be the hydrogen-bond donor Arg84 in the active site. Thus, we designed and synthesized potential inhibitors 2-6 and 8-13, having hydrogen-bond acceptors. Results of molecular docking, synthetic method, and enzyme inhibition for the diketo acid derivatives will be shown in the presentation.

MS.D1.P.561 Complexation Reactions of Nicotine Alkaloids Beata Jasiewicz, Karolina Malczewska-Jaskóła, Anna Gąsowska, Renata Jastrząb, Department of Chemistry, Adam Mickiewicz University, Poznań (Poland). E-mail: [email protected] [1] P. Yuan et al. Nature, 2009, 458, 909. [2] A. Dias et al. Nature, 2009, 458, 914. [3] J. Tomassini et al. Antimicrob Agents Chemother., 1994, 38, 2827. [4] J.C. Hastings et al. Antimicrob Agents Chemother., 1996, 40, 1304. [5] Y. Ishikawa, S. Fujii. Bioinformation, 2011, 6, 221.

Keywords: influenza virus, metalloenzyme RNA polymerase, structure-based drug design

MS.D1.P.560 Bioequilibria of Anticancer Ru(II,III) Compounds Tamás Jakusch,a Éva Sija,a Éva Anna Enyedy,a Tamás Kiss,a,b Christian G. Hartinger,c,d Bernhard K. Keppler,d aDepartment of Inorganic and Analytical Chemistry, University of Szeged, Szeged (Hungary). b Bioinorganic Chemistry Research Group of the Hungarian Academy of Sciences, University of Szeged, Szeged (Hungary). cSchool of Chemical Sciences, The University of Auckland, Auckland (New Zealand). dInstitute of Inorganic Chemistry, University of Vienna, Vienna (Austria) E-mail: [email protected] Ruthenium compounds are highly potent antitumor agents and especially efficient in the treatment of metastases. NAMI-A and KP1019 are the two most promising Ru(III) compounds being in clinical Phase 2 trials. Development of new organometallic Ru(II) compounds with potential antitumor activity also attracts attention [1] The solution properties of these complexes can be one of the key information for understanding their possible biotransformation ways. In contrast with other Ru(III) compounds the EDTA complex of Ru(III) is kinetically labile in acidic pH and the Cl- and one of the carboxylates can be replaced by bidentate ligands under fast kinetic conditions. The pH dependent speciation of [Ru(III)-EDTA] and [Ru(II)( h6-p-cymene)(H2O)3]2+ with some (O,O/N/S) type bidentate ligands have been studied in our laboratory by various methods. The main finding is, that ruthenium in both oxidation states has much higher affinity to (O,S) type ligands than to (O,O) or (O,N), which may mean that the importance of the Ru-thiolate interaction during biotransformation reactions of the drug candidate compounds most probable are more important than believed earlier. Acknowledgements. The work was supported by the Hungarian Research Fund OTKA K77883 and the Hungarian Austrian Action Foundation. It was also financed by the EU in the frame of the TÁMOP4.2.1/B-09/1/KONV-2010-0005 project. ÉAE and TJ acknowledge the financial support of Bolyai J. Research Fund.

Nicotine (1) and anabasine (2) belongs to the group of nicotinoids and have been established to be a selective α7-nAChR (neuronal nicotinic acetylcholine receptor) agonist in an animal model with low toxicity for the potential treatment of schizophrenia [1], [2], [3]. Consequently, considerable efforts has been focused on the development of new syntheses of nicotine and anabasine analogues and derivatives. It is known that some metal complexes can modulate biological activity of organic ligands. Of particular importance in the field of synthetic and biological chemistry are zinc and copper(II) complexes because of the role those elements plays in biological systems. The interaction of these atoms with drugs is a subject of considerable interest. Recently, we have obtained N-methylanabasine (3) complexes with zinc salts [4]. X-ray analysis showed that two N-methylanabasine units and two halogen anions form a tetrahedral coordination around the Zn+2 cation. Herein we report the synthesis and spectroscopic characterization of Cu(II) complexes with nicotine (1). The studies in solid state (FTIR, MS spectroscopy and X-ray analysis) show that nicotine, similarly to N-methylanabasine, acts as a monodentate ligand utilizing for this purpose the pyridine nitrogen atom. The simply stoichiometry CuX2/nicotine was confirmed by elemental analysis. Additionally, the studies of the Cu(II)/nicotine system were performed in aqueous solution using the potentiometric method with computer analysis of the data, visible and electron paramagnetic resonance spectroscopies. The composition and overall stability constants of the complexes were determined by the pH-metric study and the coordination sites were identified by spectroscopic methods. In the binary system the MHL and ML type complexes were formed in 1:1 metal:ligand ratio.

[1] P.A. Newhouse, M. Kelton, Pharm. Acta Helv, 2000, 74, 91-101. [2] G.K. Lloyd, M. Williams, J. Pharmacol. Exp. Ther, 2000, 292, 461-467. [3] L. E. Hebert, P. A. Scherr, J. L. Bienias, D. A. Bennett, D. A. Evans , Arch. Neurol, 2003, 60, 1119-1122. [4] M. Wojciechowska-Nowak, B. Jasiewicz, W. Boczoń, B. Warżajtis, U. Rychlewska, J. Mol. Struct, 2011, 997, 15-19.

Keywords: nicotine alkaloids, complexation reaction, Cu(II) salts

MS.D1.P.562

[1] W. Kandioller, A. Kurzwenhart, M. Hanif, S.M. Meier, H. Henke, B.K. Keppler, C.G. Hartinger, J. Organomet. Chem., 2011, 696, 999-1010.

Keywords: ruthenium, anticancer, thiolate

Interactions of DNA with an Antitumor Pt(IV) Complex Activated by Visible Light Jana Kasparkova,a,b Jitka Pracharovaa, Lenka Zerzankova,b Jana Stepankova,b Olga Novakova,b Nicola J. Farrer,c Peter J. Sadler,c Viktor Brabec,a,b aDepartment of Biophysics, Faculty of Science, Palacky University, Olomouc (Czech Republic). bInstitute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Brno (Czech Republic). cDepartment of Chemistry, University of Warwick, Coventry (United Kingdom). E-mail: [email protected]

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Poster Sessions The PtIV diazido complex trans,trans,trans[Pt(N3)2(OH)2(pyridine)2] (1) is unreactive in the dark but is cytotoxic when photoactivated by UVA and visible light. We have shown that 1 when photoactivated accumulates in tumor cells and binds strongly to nuclear DNA under conditions in which it is toxic to tumor cells. The nature of the DNA adducts, including conformational alterations, induced by photoactivated 1 are distinctly different from those produced in DNA by conventional cisplatin or transplatin. In addition, the observation that major DNA adducts of photoactivated 1 are able to efficiently stall RNA polymerase II more efficiently than cisplatin suggests that transcription inhibition may contribute to the cytotoxicity levels observed for photoactivated 1. Hence, DNA adducts of 1 could trigger a number of downstream cellular effects different from those triggered in cancer cells by DNA adducts of cisplatin. This might lead to the therapeutic effects that could radically improve chemotherapy by platinum complexes. The findings of the present work help to explain the different cytotoxic effects of photoactivated 1 and conventional cisplatin and thereby provide new insights into mechanisms associated with the antitumor effects of platinum complexes photoactivated by UVA and visible light [1]. [1] J. Pracharova, L. Zerzankova, J. Stepankova, O. Novakova, N. Farrer, P.J. Sadler, V. Brabec, J. Kasparkova, Chem. Res. Toxicol., 2012, in press, DOI 10.1021/tx300057y.

Keywords: anticancer platinum, photoactivation, DNA damage

MS.D1.P.563 Micro Determination of Ebastine in its Solid Dosage Form Essam F. Khamis*, Rasha M. Youssef, Mahmoud A. El-Sayed, Mona M. Abdel Moneim, Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Alexandria University, Alexandria, 21521, (Egypt). E-mail: [email protected] Three sensitive and validated colorimetric methods are described for the micro-determination of ebastine (EBS) in tablets. The first method is based on the interaction of EBS which contains a ketonic group with 2,4-dinitrophenylhydrazine (2,4-DNP) in the presence of an acid catalyst, followed by treatment with a methanolic solution of potassium hydroxide. An intensely colored chromogen was formed that was measured in dimethylformamide, as the diluting solvent, at 555 nm. Selection of this reagent was based on the higher reactivity of 2,4-DNP compared to other hydrazine derivatives and the presence of strong chromophore group in its structure that enables its use for the colorimetric determination of several aldehydes and ketones. In addition of being specific for carbonyl groups 2, 4-DNP has advantages over other reagents as there is no need to extract the product formed. Also the hydrazone product is more red-shifted than those of other methods. The colored hydrazone product was found to be more stable relative to the corresponding products from all reported methods. The stability of the colored product formed can be accounted for by the fact that the reaction is irreversible under the established experimental conditions, and the chromogen formed is stable as the potassium salt. The second method is based on the formation of an ion-pair complex between the drug and bromocresol green (BCG) with subsequent measurement of the developed color at 411 nm. The third method is based on the fact that EBS is a basic nitrogenous compound that can form picrate salt with picric acid (PCA) followed by subsequent measurement of resulted color at 400 nm. The use of both BCG and PCA to react with EBS has advantages over other reagents in reported methods in that no much care is needed regarding the pH of the reaction and no need for heating or waiting for a long time. All the reaction conditions have been studied. The detection limits were 0.3, 1.2 and 3.0 for method I, II and III, respectively. Beer’s law

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was obeyed in the concentration ranges of 1–4 µg/mL, 4–15 µg/mL, and 10–40 µg/mL for method I, II and III, respectively, with good correlation coefficients. The proposed methods were successfully applied to the assay of EBS in tablets. Moreover, they were validated according to the USP validation elements. The results were also compared favorably with those of a previously reported method. Keywords: Ebastine, colorimetry, tablets

MS.D1.P.564 Structural Approach to Mn(II) Complexes as SOD and Catalase Mimics Muhammet Kose, Vickie McKee, Chemistry Department, Loughborough University, Loughborough (UK). E-mail: m.kose@ boro.ac.uk Manganese is one of the essential transition metals in biological systems and it is found in the active site of enzymes such as electrontransfer reactions of mitochondrial superoxide dismutase (SOD), bacterial catalases and photosystem II in green plant photosynthesis [1]. Manganese model compounds have been drawn much attention because of its low toxicity in mammalian systems. Considerable efforts have been made to obtain stable, non-toxic, and inexpensive low molecular weight biomimetic molecules which are capable of catalyzing superoxide dismutation and therefore to provide important therapeutic applications. Riley and his co-workers prepared the most active (to date) seven-coordinate Mn(II) complexes with computer aided modelling as SOD mimics [1, 2] and one of these complexes has been shown high efficacy for a variety of animal models of inflammation, ischemia reperfusion injury and pain [3]. For this purpose, we prepared some related macrocyclic and acyclic systems. Macrocycle (H2L1) prepared by a Schiff base condensation reaction of 2,6-diformylpyridine and 1,3-diaminopropan-2-ol in the presence of Ba(II) as the initial template ion [4, 5] and Ba(II) was displaced one or more Mn(II) ions via trasmetallation reactions. Mononuclear ring-contracted and pentanuclear ring-expanded Mn(II) complexes were obtained from methanol or ethanol and acetonitrile solvents respectively. Additionally, acyclic Mn(II) complexes (H2L5) were prepared by template reactions. The structures of all complexes in this work were determined by single X-ray diffraction study and their superoxide dismutase activity was measured by an indirect method using SOD Assay KitWST. Moreover, catalase activities of the complexes were tested by measuring oxygen evolved.

[1] (a) Riley, D. P.; Schall, O. F. Adv. Inorg. Chem, 2006, 59, 233-263. (b) Riley, D. P.; Chem. Rev. 1999, 99, 2573-2587. [2] Liu, G. F.; Fillipović, M.; Heinemann, F. W.; Ivanović-Bermazović, I., Inorg. Chem., 2007, 46, 88258835. [3] DiNapoli, M. D.; Papa, F., IDrugs, 2005, 8, 67-76. [4] James, L., Kose, M., Metcalfe, T., McKee, V., J. Chem. Crystallogr., 2011, 41,577–581, 2011. [5] (a) Brooker, S.; McKee, V.; Shepard, W. B.; Pannell, L.K. J. Chem. Soc., Dalton Trans., 1987, 2555-2562. (b) Brooker, S.; McKee, J. Chem. Soc., Chem. Commun., 1989, 619-620.

Keywords: manganese, biomimetic, X-ray structure

MS.D1.P.565

MS.D1.P.566

An Azo-azomethine Dye and its Cu(II) Complex: Synthesis, Crystal structure, Spectral, Thermal and Electrochemical Properties

Cytotoxicity and DNA Binding Studies of Copper(II) Salicylaldehyde Dibenzyl Semicarbazone Complexes Peter Peng Foo Lee,a Kenny Zhi Xiang Khong,a Yaw Kai Yan,a Ramon Vilar,b aNatural Sciences & Science Education, National Institute of Education, Nanyang Technological University, Singapore (Singapore). b Department of Chemistry, Imperial College London, London (UK). E-mail: [email protected]

Tuğba Eren1, Muhammet Kose2, Nurcan Kurtoglu3, Vickie McKee2 and Mukerrem Kurtoglu,1 1Kahramanmaras Sutcu Imam University, Kahramanmaras, 46050, Turkey 2Department of Chemistry, Loughborough University, Leics. LE11 3TU, UK 3Department of Textile, Kahramanmaras Sutcu Imam University, K.Maras, 46050, Turkey. E-mail:[email protected] (M.Kurtoglu) The growing interest on the coordination compounds of copper with various N-donor ligands, comes mainly from their capability of combining characteristic structural flexibility, mimicking of protein active sites, easy of preparation and stabilization of both oxidation states of the metal usual in biological systems. Considerable interest in various N and O donor ligands especially Schiff bases and their transition metal complexes have also grown in the areas of chemistry and biology due to biological activities, such as antiviral, antitumor, antibactericial and antifungicidal properties[1-2]. In this study, a new azo-azomethine dye, (nx-ipaH) and its Cu(II) complex, [Cu(nx-ipa)2] were synthesized and characterized by the analytical and spectroscopic methods such as elemental analayses, infrared, 1H-, 13C NMR and mass spectra. Single crystals suitable for X-ray diffraction studies were obtained for both the ligand and metal complex. In the structure of the ligand, there is an intramolecular phenol-imine hydrogen bond (O1...N1) with a distance of 2.580(3)Å. There are also weaker intermolecular hydrogen bond type interactions CH...O and CH...N=N stabilising the structure. In the structure of the complex, the central metal atom is coordinated to two phenolate oxygen atoms and two imine nitrogen atoms of two azo-Schiff base molecules in a distorted square-planar geometry.

Fig. The structure of Cu(II) complex

Thermal properties of the prepared compounds were investigated by TGA. Electrochemical properties of the ligand and its copper(II) complexes were investigated in the 1x10-3-1x10-4 M DMF and CH3CN solvents at different scan rates. The ligand and its copper(II) complex showed both reversible and irreversible processes. [1] Tamburini, V. P.A., Coord. Chem. Rev., 2004, 248, 1717–2128. [2] Akine, S.; Nabeshima, T., Dalton Trans., 2009, 47, 10395-10408.

Keywords: Azo-azomethine, structure, Spectroscopy

The copper(II) complexes of substituted salicylaldehyde dibenzyl semicarbazones were evaluated for their DNA binding properties via spectrophotometric DNA titration and the thiazole orange (TO) displacement assay. The affinities of these complexes toward duplex (ds17, ds26 and calf-thymus) and quadruplex (HTelo and c-myc) DNA have been investigated. Results showed that the complexes [Cu(L) (Cl)] and [Cu(L)(C5H5N)]+, where L denotes the semicarbazone ligand (HO)2C6H3CH=N‒NHCON(CH2C6H5)2 deprotonated at the ortho OH group, can displace the fluorescent probe, TO, with DC50 values of 1.93 μM and 1.33 μM respectively. They can also bind strongly to Human Telomeric (HTelo) quadruplex DNA, with binding constants of 2.00 × 105 M‒1 and 5.00 × 105 M‒1, which represents a 6‒fold and 17‒fold selectivity, respectively, over duplex calf-thymus DNA. These two Cu(II) complexes also showed high cytotoxicity towards the MOLT‒4 (leukaemia) cell line, with IC50 values of 7.4 × 10‒6 M and 4.8 × 10‒6 M respectively. Keywords: quadruplexes, copper(II) complexes, DNA binding

MS.D1.P.567 New Copper(I/II) Complexes coordinated with DNA bases adenine and guanine Bárbara Leite Ferreira,a Paula Brandão,a Teresa M. Santos,a M. Meireles,b S. Martins,b Vítor Félix,a,c, aCICECO & Chemistry Department, University of Aveiro, 3810-193 Aveiro (Portugal), b Chemistry & Biochemistry Department, University of Lisbon, 1749016 Lisbon (Portugal), cHealth Sciences Department, University of Aveiro, 3810-193 Aveiro (Portugal). E-mail: [email protected] Over the past decades, metal complexes have had enormous success as cytotoxic drugs against cancer related diseases. Cis[Pt(NH3)2Cl2] is the paradigmatic example of a “simple” transition metal complex widely used as an anti-tumoral drug. However, its effectiveness was early clouded by undesirable side effects along with acquired drug resistance [1]. This clearly showed that selectivity and specificity are indeed the main keys to design and produce better and effective cytotoxic and anti-tumoral new drugs. Because of these drawbacks, the development of more specific and less toxic new anticancer metal-based drugs is a main object of attention of nowadays research, directed towards poly-nuclear Pt, Ru, Rh, Pd, and more recently, to Au, Cu and Fe complexes [1]. Among the new multi-metal centred complexes paradoxally those with copper only in the last few years have been explored. Taking into account copper essentiality and bio-compatibility, the easy available copper salts as starting materials, besides their cheaper price when compared with Pt, Ru, Rh, it appeared to us an excellent field of work [2,3]. In this work we describe the synthesis of new copper(I/II) complexes with DNA bases (adenine and guanine), coordinated either as monodentate or bridging bidentate ligands. The new prepared compounds have been characterized by single-crystal X-ray diffraction, FTIR, UV-VIS and RMN. Their cytotoxic properties were also evaluated, using the standard MTT assay against human cell lines, in order to test their capacity for anti-tumoral applications.

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Poster Sessions The new copper(I/II) complexes, coordinated with adenine and guanine DNA bases, were successfully synthesized and characterized, mainly regarding their crystal structure, and their cytotoxic properties were positively confirmed. [1] A. Bergamo, C. Gaiddon, J. Schellens, J. H. Beijnen, G. Sava. Smith, J. Inorg. Biochem., 2012, 106, 90-99. [2] I. Iakovidis, I. Delimaris, S. M. Piperakis, Molecular Biology International, 2011, 2011, Art. ID 594529, 1-13. [3] G. Crisponi, V. M. Nurchi, D. Fanni, C. Gerosa, S. Nemolato, G. Faa, Coord. Chem. Reviews, 2010, 254(7-8), 876–889.

Keywords: copper complexes, DNA bases, anti-tumoral activity

MS.D1.P.568 M2L4 Metallosupramolecular Nanocages as Potential Cisplatin Drug Delivery Vectors James E. M. Lewis,a Scott A. Cameron,a James D. Crowley,a* a Department of Chemistry, University of Otago, PO Box 56, Dunedin, New Zealand. E-mail: [email protected]; jcrowley@ chemistry.otago.ac.nz There are over 200 varieties of cancer that combined claimed the lives of nearly 13 million people worldwide in 2008.[1] Since cisplatin’s cytotoxic properties were discovered in the 1960s,[2] platinum-based anticancer therapeutics have become ubiquitous in the treatment regimes of certain cancers. Unfortunately these drugs indiscriminately affect healthy cells as well as cancerous ones, giving rise to severe side effects. In addition, poor aqueous solubility and resistant cells lines reduce the efficacies of these drugs. As a result a variety of potential drug delivery vectors are currently being investigated to circumvent these issues.[3] Following on from work in the field of metallosupramolecular drug delivery vectors,[4] we have recently reported the synthesis of a Pd2L4 cage capable of encapsulating two molecules of cisplatin within its cavity.[5] Furthermore we have demonstrated the potential for stimuliresponsive dis- and re-assembly of the cage architecture, allowing release of the encapsulated cisplatin through application of a stimulus. We have subsequently been investigating ways to improve the functionality, solubility, and host-guest chemistry of this system through synthetic methods. We will present our latest results towards the synthesis of a potentially targeted metallosupramolecular cisplatin delivery system.

MS.D1.P.569 Macroacylic Bis(Dithiocarbazate) Complexes: Synthesis, Characterization and Bioactivity May Lee Lowa,b, Mohamed Ibrahim M. Tahira, Pierre Dorletc Régis Guillotd, Thahira Begum Ravoofa, Rozita Roslie, Nicolas Delsucb, Clotilde Policarb, Karen A. Crousea. aDepartment of Chemistry, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia) b Laboratoire des BioMolécules, UMR 7203, CNRS-ENS-UPMC, Département de Chimie, Ecole Normale Supérieure, 24 rue Lhomond 75005 Paris (France) cUMR 8221 CNRS-CEA-Univ Paris XI Bât 532 CEA Saclay 91191 Gif-sur-Yvette (France) dInstitut de Chimie Moléculaire et des Matériaux d’Orsay, Bât. 420 Université Paris-Sud, 91405 Orsay (France) eDepartment of Obstetrics and Gynaecology, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia).E-mail: [email protected] Macrocylic and macroacylic sulphur-nitrogen containing Schiff base ligands such as those derived from bis(dithiocarbazate) are of increasing interest because of their versatility [1], various coordination abilities and potential applications in biology which range from therapeutic drug candidates to diagnostic agents and in providing synthetic models for the metal containing sites in metalloproteins and metalloenzymes [2-3]. Recently we have prepared Schiff base complexes of the type ML (M = Cu(II), Mn(II) or Zn(II), L = SMHD or SBHD; e.g. Figure 1) which were characterized with various physico-chemical (elemental analysis, molar conductivity, magnetic susceptibility, thermal analysis) and spectroscopic (infrared, electronic, mass, nuclear magnetic resonance, single crystal X-ray diffraction) methods. The solution behaviour of ML were also investigated by electron paramagnetic resonance (EPR) and electrochemistry. The antibacterial and anticancer activities of ML were evaluated and the structure-activity relationships of this series will be discussed.

Figure 1: (clockwise from top left) ORTEP diagrams of SMHD, CuSMHD, and CuSBHD, depicted with thermal ellipsoids at 50% probability. [1] IARC, GLOBOCAN 2008 2010. [2] B. Rosenberg, Nature 1965, 205, 698. [3] B. W. Harper, A. M. Krause-Heuer, M. P. Grant, M. Manohar, K. B. Garbutcheon-Singh, J. R. Aldrich-Wright, Chem. Eur. J. 2010, 16, 7064. [4] B. Therrien, G. Süss-Fink, P. Govindaswamy, A. K. Renfrew, P. J. Dyson, Angew. Chem. Int. Ed. 2008, 47, 3773. [5] J. E. M. Lewis, E. L. Gavey, S. A. Cameron, J. D. Crowley, Chem. Sci. 2012, 3, 778.

Keywords: cisplatin, supramolecular, drug

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[1] Vigato, P.A., Tamburini, S., Coord. Chem. Rev., 2004, 248, 1717-2128. [2] Paterson, B.M. and Donnelly, P.S., Chem. Soc. Rev., 2011, 40, 3005-3018. [3] Ali, M.A., Hossain, S.M.G., Majumder, S.M.M.H., Uddin, M.U., Polyhedron, 1987, 6, 8, 1653-1656.

Keywords: dithiocarbazate, schiff base, macroacyclic NNSS ligands

MS.D1.P.570

MS.D1.P.571

Chitosan Coated Nanoparticles Functionalized with Pd(II) Complexes Jorge Manzura, b, Mabel Tobara,b, Yuri Echevarríaa, Evgenia Spodineb,c, Wilfredo Hernándezd, aFac. Cs. Físicas y Matemáticas, U. de Chile, Chile, bCEDENNA, Chile, cFac. Cs. Químicas y Farmacéuticas, U. de Chile, Chile, dFac. Ingeniería Industrial, U. de Lima, Perú. E-mail: [email protected]

Novel Trifluoromethylated Metallocenes – Potential new anticancer drugs? Marcus Maschke,a Max Lieb,a and Nils Metzler-Nolte,a aInorganic Chemistry I – Bioinorganic Chemistry, Ruhr-University Bochum, Bochum (Germany). E-mail: [email protected]

Thiosemicarbazones derivatives and their transition metal complexes have been shown to possess a wide variety of biological activities as antiviral, antimicrobial, anticancer, and antitumor agents [1,2]. Recently, in vitro studies of the platinum(II) and palladium(II) bis-chelate complexes with benzaldehyde thiosemicarbazone derivatives against different human tumor cell lines showed that these metal complexes are more cytotoxic than their respective ligands [3]. In cancer treatment a targeted controlled delivery of the anticancer drugs is desirable to avoid the damage of the normal tissue. For this purpose, superparamagnetic iron oxides are emerging as promising candidates due to their ultrafine size and biocompatibility. For the improvement of targeting and biocompatibility the nanoparticles are coated with different species. Among others, chitosan an aminopolysaccharide, is an interesting choice due to many significant biological (biodegradable, biocompatible, bioactive) and chemical properties (polycationic, hydrogel, contains reactive groups such as OH and NH). Besides, chitosan is characterized by its high affinity for metal ions and also can bind metal complexes. In this work we describe the synthesis and characterization of thiosemicarbazone based palladium(II) complexes with known anticancer properties, and the adsorption of selected compounds on superparamagnetic magnetite nanoparticles coated with chitosan. Magnetite nanoparticles coated with chitosan were prepared by co-precipitation of ion(III) and iron(II) chlorides in basic media in the presence of variable amounts of chitosan. A suspension of magnetite nanoparticles in a solution of the complexes in dimethylformamide was irradiated with microwave radiation for 10 minutes, the nanoparticles were separated with the aid of a magnet, washed with DMF and acetone, and dried in vaccum. The adsorption of the complexes was confirmed by IR and elemental analysis. The percentage of the absorption increases with the concentration of the complex and the amount of the chitosan used in the coating of the nanoparticles.

In the last decades, bioinorganic chemistry has attracted much attention by development of therapeutic compounds, such as ferrocifen and ferroquine.[1-4] Both highlight the possible medical applications of bioinorganic compounds. However, widely used bioinorganic compounds such as the anti-cancer drug cisplatin, are toxic due to their lack of selectivity. Nevertheless worldwide cancer patients are still treated with cisplatin. For this reason, new compounds have to be found which show greater selectivity, specific for cancer cells. Among the above mentioned therapeutic agents fluorinated species are nearly unknown. On the other hand, fluorinated compounds such as 5-fluorouracil or 5-fluorocytosine are among the oldest commercially available chemotherapeutic agents. Therefore, the combination of metallocenes and fluorinated substituents is interesting. The presented compounds were synthesized by cycloaddition reactions and provide important properties like enhanced lipophilicity and higher cytotoxicity (Scheme 1). Moreover, the strong electron withdrawing effect of the fluorinated substituents influences the redox behavior of the metal center. These substituents reduce the electron density at the ferrocene moiety inducing a higher resistance towards oxidation. Synthesis and biological evaluation of further novel fluorine-containing metallocenes will be discussed.

Scheme 1 Synthesis of novel cytotoxic trifluoromethylated metallocene triazoles. [1] G. Gasser, I. Ott, N. Metzler-Nolte, J. Med. Chem, 2010, 54, 3-25. [2] G. Jaouen et al CHIMIA, 2007, 61, 716-724. [3] D. R. van Staveren, N. MetzlerNolte, Chem. Rev., 2004, 104, 5931-5986. [4] M. Salmain, N. Metzler-Nolte, in: Ferrocenes (Edt. P. Stepnicka), John Wiley and Sons, Chinester, 2008, 499-639.

Keywords: bioinorganic chemistry, cytotoxicity, fluorinated metallocenes

MS.D1.P.572 [1] A.K. Salman, Y. Mohamad, Eur. J. Med. Chem. 2009, 44, 2270 – 2274. [2] K. S. Abou Melha, J. Enz. Inhib. Medic. Chem. 2008, 23, 493 – 503. [3] W. Hernández, J. Paz, J. Vaisberg, E. Spodine, R. Richter, L. Beyer, Bioinorg. Chem. Appl. 2008, ID 690952.

Keywords: chitosan coated nanoparticles, Pd(II) complexes, thisemicarbazone ligands Acknowledgements: W. H. thanks Universidad de Lima Scientific Research Institute for financial support. E. S. and J. M. thank FB0807 project.

Gold Compounds: New Anticancer Drug Candidates Lara Massai,a Federica Scaletti,a Chiara Gabbiani,b Luigi Messori,a a Department of Chemistry, University of Florence, Sesto Fiorentino, (Italy). bDepartment of Chemistry and Industrial Chemistry, University of Pisa, Pisa (Italy). E-mail: [email protected] Metal complexes represent today an important part of the available resource of cytotoxic and antitumor agents. Platinum (II) compounds, specifically targeting genomic DNA, e.g. cisplatin and carboplatin, have found wide application in clinical cancer treatments during the last 25 years. However, platinum drugs manifest severe side effects: nephrotoxicity, emetogenicity, neurotoxicity etc… Therefore it is attractive to focus attention to non-platinum cytotoxic metallodrugs as

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Poster Sessions valuable alternatives. Gold compounds form a new class of promising anticancer drug candidates [1]. There is a strict analogy between Au(III) and Pt(II); in addition gold has a rich coordination chemistry and very interesting redox properties. The main goals of our researches are the following: to model the binding interactions of gold with proteins, to understand the mode of action of cytotoxic gold compounds at the cellular level; to identify their primary molecular targets. A small panel of representative gold(III) compounds (Auoxo6, Au2phen and Aubipyc) have been characterised. For comparison purposes similar studies were carried out on Auranofin, a gold(I) complex which is a clinically established antiarthritic drug and also a potent cytotoxic agent in vitro. Their solution behaviour and their stability under experimental conditions have been studied through UVvis spectroscopy. Adduct formation with gold compounds and small model proteins (lysozime, cytochrome c and ubiquitin) was monitored by ESI-MS methods. Auoxo6 and Au2phen typically produced adducts with lysozime and cytochrome c where one or more “naked” gold(I) ions are coordinated to protein side chains. This behaviour is explained in terms of reduction of gold(III) to gold(I). Aubipyc gave adducts with proteins where the structural core of the complex and the gold oxidation state +3 are conserved, due to its higher redox stability. These studies will soon be extended to consider other proteins that are postulated targets for gold compounds. For instance, a number of studies suggest that gold compounds are strong inhibitors of thioredoxin reductase [2]. We will try to test comparatively the inhibitory potential of the study gold compounds toward this enzyme through in vitro assays. [1] S. Nobili, E. Mini, I. Landini, C. Gabbiani, A. Casini and L. Messori Med. Res. Rev., 2010, 30(3), 550-580. [2] A. Pratesi, C. Gabbiani, M. Ginanneschi and L. Messori Chem. Commun., 2010, 46(37), 7001-7003.

Keywords: gold, anticancer, proteins

MS.D1.P.575 Kinetics of GaNOTA formation from weak Ga-citrate complexes Jean-François Morfin, Eva Jakab-Toth, Centre de Biophysique Moléculaire, CNRS UPR 4301, Orléans (France). E-mail: [email protected] Gallium complexes are gaining increasing importance in biomedical imaging thanks to the practical advantages of the 68Ga isotope in Positron Emission Tomography (PET) applications. 68Ga has a short half-time (t1/2 = 68 min); thus the 68Ga complexes have to be prepared in a limited time frame. The acceleration of the formation reaction of gallium complexes with macrocyclic ligands for application in PET imaging represents a significant coordination chemistry challenge.[1] Here we report a detailed kinetic study of the formation reaction of the highly stable Ga(NOTA) (log KGaNOTA = 31.0) [2] from the weak citrate complex (H3NOTA = 1,4,7-triazacyclononane-1,4,7- triacetic acid). The transmetalation has been studied using 71Ga NMR over a large pH range (pH = 2.01_6.00). The formation of Ga(NOTA) is a two-step process. First, a monoprotonated intermediate containing coordinated citrate, GaHNOTA(citrate)*, forms in a rapid equilibrium step. The rate-determining step of the reaction is the deprotonation and slow rearrangement of the intermediate accompanied by the citrate release. The observed reaction rate shows an unusual pH dependency with a minimum at pH 5.17. In contrast to the typical formation reactions of poly(amino carboxylate) complexes, the Ga(NOTA) formation from the weak citrate complex becomes considerably faster with increasing proton concentration below pH 5.17. We explain this unexpected tendency by the role of protons in the decomposition of the GaHNOTA(citrate)* intermediate which

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proceeds via the protonation of the coordinated citrate ion and its subsequent decoordination to yield the final product Ga(NOTA). [3] The stability constant of this intermediate, log KGaHNOTA(citrate)* = 15.6, is remarkably high compared to the corresponding values reported for the formation of macrocyclic lanthanide(III)-poly(amino carboxylates). These kinetic data do not only give mechanistic insight into the formation reaction of Ga(NOTA), but might also contribute to establish optimal experimental conditions for the rapid preparation of Ga(NOTA)-based radiopharmaceuticals for PET applications.

[1] M. Fania, J.P. Andre, H. R. Maecke, Contrast Media Mol.Imaging 2008, 3, 67. [2] E. T. Clarke, A.E. Martell, Inorg. Chim. Acta, 1991,181, 273. [3] J.F. Morfin, E. Toth, Inorg. Chem., 2011, 50, 20, 10371.

Keywords: Gallium, Positron Emission Tomography, Kinetics

MS.D1.P.576 Syntheses of Glucopyranosyl Schiff base Zinc(II) Complexes and their DNA Cleavage Activities Misaki Nakai,a Hironobu Fukuda,a Shigenobu Yano,b,c Yasuo Nakabayashia, aFaculty of Chemistry, Materials and Bioengineering, Kansai University, Osaka (Japan). bOffice of Society-Academia Collaboration for Innovation, Kyoto University, Kyoto (Japan). c Graduate School of Material Science, Nara Institute of Science and Technolugy, Nara (Japan). E-mail: [email protected] New glucopyranosyl Schiff base zinc complexes, [Zn(GlcSal)2] (1), [Zn(AcOGlcSal)2] (2), [Zn(GlcNaph)2] (3), and [Zn(OAcGlcNaph)2] (4) (GlcSalH = N-(2-deoxy-b-D-glucopyranosyl-2-salicylaldimine), AcOGlcSalH=N-(2-deoxy-b-D-1,3,4,6-tetraacetylglucopyranosyl)2-salicylaldimine, GlcNaphH = 1-(D-glucopyranosyl-2’-deoxy2’-iminomethyl) -2-hydroxynaphthalene, OAcGlcNaphH = 1-(D-1,3,4,6-tetraacetylglucopyranosyl-2’-deoxy-2’-iminomethyl)-2hydroxynaphthalene were synthesized and characterized by spectral and analytical methods. The interaction between the Zn complexes and mononucleotides was investigated by using 1H NMR, UV-vis spectroscopes, and fluorescence spectroscopes. Mononucleotides, cytidine 5’-monophosphate (CMP) and uridyl 5’-monophosphate (UMP) interacted with these complexes to form a 1 : 1 complex or 1 : 2 complex with ligand disassociations, depending on the presence of the hydroxyl group of glucopyranosyl substituents. The intrinsic biding constant (Kb) values, which were estimated from UV-vis spectral change with increased addition of CMP, were decreased in the order of 3 > 4 > 2 > 1. In the fluorescence spectra of 3 and 4, the fluorescence intensities were decreased with an addition of CMP. The decrease of fluorescence intensity of 3 was greater than that of 4. These decrease suggested that a coordination of CMP cleaved the bonds between the imino groups and Zn atoms, and these cleavage was also dependent on glucopyranosyl groups. The DNA cleavage activities of Zn complexes and Zn(Oac)2 were studied using plasmid DNA (pBR322) in a medium of 5 mM TrisHCl / 50 mM NaCl buffer in the presence of H2O2. The DNA cleavage activity decreased in the order of 3 > 4, 2 > 1 > Zn(OAc)2, indicating the significant promoting effect of the glucopyranosyl Schiff base ligand and the participation of the glucopyranosyl hydroxyl groups in the cleavage mechanism. The mechanism of the DNA cleavage by 1 and 2 was investigated by evaluation of the effect of a hydroxyl radical scavenger and a singlet oxygen quencher under aerobic conditions.

The former exhibited little effect, excluding the hydroxyl radical as an active species and supporting the hydrolysis mechanism for the main process of the DNA cleavage. The latter quencher somewhat hindered the cleavage, indicating the partial participation of a singlet oxygen as a competitive active species in the present system.

bond formation. As no single crystal for X-ray diffraction studies were obtained, the molecular structures of 1-3 were optimized using DFT level of theory (B3LYP). The cytotoxic activities of the bzox, imzt and compounds 1-3 were tested against murine mammary adenocarcinoma cell line (LM3). Cells were exposed to a range of drug concentrations (100–6.25 mg/mL) for 24 h and cell viability was analyzed by MTT assay. The ligands showed no drug response at concentrations < 100 mg/mL. However, in most of the cases, coordination of these ligands on palladium center resulted in higher cytotoxic activities. After treatment of LM3 cells with compounds 1-3 and cisplatin, it was noticed that all cyclopalladated exhibited interesting IC50 values in the range 12.5 – 6.25 mg/mL, which were comparable to that found for cisplatin (IC50 = 9.0 mg/mL). [1] A. Garoufis, S.K. Hadjikakou, N. Hadjiliadis, Coord. Chem. Rev., 2009, 253, 1384-1397. [1] A. D. Ryabov, J. G. M. Kazankov, A. K. Yatsimirsky, L. G. Kuz´mina, O. Y. Burtseva, N. V. Dvortsova, and V. A. Polyakov, Inorg. Chem., 1992, 31, 3083-3090.

Fig. Structures of Zn complexes in this study.

Keywords: zinc complex, sugar linked metal complex, DNA cleavage

MS.D1.P.577 Synthesis and Cytotoxicity Evaluation of Palladacycles Bearing Benzaldehydeoxime Adelino V. G. Netto,a Sahra C. Lemos,a Antonio E. Mauro,a Regina C. G. Frem,a Rodrigo A. de Souza,a Oswaldo Treu-Filho,a Iracilda Z. Carlos,b aInstitute of Chemistry, São Paulo State University-UNESP, Araraquara (Brazil). bSchool of Pharmaceutical Sciences, São Paulo State University-UNESP, Araraquara (Brazil). E-mail: adelino@ iq.unesp.br The clinical success of cisplatin in the treatment of human malignancies has stimulated great efforts in the development of new metal-based compounds for diagnostic and/or therapeutic purposes. In particular, the biological activity of cyclopalladated complexes has attracted considerable interest as a number of newly synthesized derivatives exhibited promising cytotoxicity toward selected human tumor cell lines as well as pronounced antiproliferative activity against pathogens [1]. In this work, we present the synthesis and cytotoxicity evaluation of new mononuclear cyclopalladated species of the type [PdX(C2,N-bzox)(imzt)] {bzox = benzaldehydeoxime, imzt = imidazolidinethione, X = Cl- (1), Br-(2); I-(3)}. Compounds 1-3 were obtained from cleavage reactions involving the appropriated halidebridged [Pd(m-X)(C2,N-bzox)]2 precursor [2] with imzt in the 1:2 molar ratio. Elemental analysis results were consistent with the proposed stoichiometry. The appearance of a single gCH band at ca. 752 cm-1 for 1-3 strongly supports the 1,2-dissubstituted aromatic ring character of bzox. The coordination of imzt via thione sulfur atom is suggested by the shift to lower frequency of the band with high nC=S character from 677 cm-1 (free ligand) to ~ 643 cm-1 (1-3). The 1H NMR spectra of l-3 exhibits only one set of signals, which suggests that the presence of only one geometrical isomer of 1-3 in solution. The appearance of four aromatic resonances at, approximately, 7.23 (H3, br), 7.02 (H4, t), 7.07 (H5, t) and 7.29 (H6, d) is consistent with the presence of the C2,Northopalladated bzox moiety in the molecular structures of 1-3. The downfield shift of the HC=N proton of bzox from 8.14 ppm (free bzox) to ca. 8.36 ppm (1-3) strongly support the coordination to the metallic atom through the iminic nitrogen in all cyclopalladated compounds. An upfield shift of ca. 7 ppm of the C=S resonance observed in the 13 C{1H} NMR spectra of l-3 indicates a p-back bonding from the palladium to the thione sulfur atom and gives a clear evidence of Pd-S

Keywords: cyclopalladated, cytotoxicity, benzaldehydeoxime

MS.D1.P.578 Influence of Leaving Groups on Cytotoxicity of Platinum(II) Complexes Rafał Niekraś,a Natalia Piórkowska,a Iwona Łakomska,a Joanna Wietrzyk,b aFaculty of Chemistry, Nicolaus Copernicus University, Toruń, (Poland), bInstitute of Immunology and Eksperimental Therapy, Polish Academy of Sciences, Wrocław (Poland). E-mail: [email protected] Although cisplatin has become one of the most anticancer agent, it reveals many side effects toxicity and intrinsic or acquired resistance of tumor cells. That is why many platinum drugs have been developed in an attempt to improve the toxicity profile [1]. Leaving groups can be modified both the kinetics of hydrolysis and the reactivity of the drug, so cytotoxicity of Pt(II) complexes may be influenced by the nature of the leaving ligands. In addition, some Pt(II) complexes with carboxylate ions as leaving groups seem to be promising than the corresponding both chloro analogues and cisplatin [2], [3], [4]. Therefore platinum(II) complexes with 5,7-dimethyl-1,2,4triazolo[1,5-a]pyrimidine (dmtp) and leaving group (LG) of the general formula [Pt(LG)2(dmtp)2]∙xH2O where LG = Cl–, I–, CH3COO–, CCl3COO–, NO3– (Fig.1) have been synthesized and characterized by IR and multinuclear NMR. The 1H and 15N NMR spectra confirmed the complexation of the dmtp ligand giving resonance in the range: 8.909.40 ppm for H(2); 7.10-7.50 ppm for H(6). Also, significant shielding of 15N NMR signals were observed for N(3) atom indicating this atom is the binding site. The impact of mentioned above LG on the cytotoxic activity of complexes was investigated by using cell lines: T47D, A549, Balb3T3. The cytotoxicity of the carboxylates Pt(II) complexes was much higher than other.

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Poster Sessions corroborating the bridging mode of coordination of ibuprofen and ketoprofen expected for this class of ruthenium carboxylates. In order to preliminarily investigate the compounds in vitro metabolism, the ibuprofen complex was incubated (n = 3) in the presence of NADPH, rat liver microsomes in physiological buffer at 37 °C for 40 min. Control samples without NADPH were performed at the same manner described above. The HPLC results showed that the metabolism sample areas were lower when compared to the control sample areas suggesting that this complex was metabolized by the rat CYP (cytochrome P450) enzymes. FAPESP and CNPq

Keywords: metalo-drugs, in vitro metabolism, ruthenium carboxylates

Fig. 1. The route of syntheses of platinum(II) complexes with dmtp and different leaving groups. [1] M. Galanski, B. K. Keppler, Metal Based Drugs, 1995, 1, 57-63. [2] S. van Zutphen, E. Pantoja, R. Soriano, C. Soro, D. M. Tooke, A. L. Spek, H. den Dulk, J. Brouwer, J. Reedijk, Dalton Trans., 2006, 1020-1023. [3] G. H. Bulluss, K. M. Knott, E. S. F. Ma, S. M. Aris, E. Alvarado, N. Farrell, Inorg. Chem., 2006, 15, 5733-5735. [4] J. Zhang, Y. Li, J. Sun, Eur. J. Med. Chem., 2009, 44, 2758–2762.

Keywords: leaving groups, cytotoxicity, platinum(II) complex

MS.D1.P.579 Investigation of the Novel Complexes [Ru2O(carb)2(py)6]n+ (carb = ibuprofen; ketoprofen) Sofia Nikolaou,a Gabriela C. Seuanesa, Anderson R. M de Oliveira,b a Departamento de Física e Química da Faculdade de Ciências Farmacêuticas de Ribeirão Preto, University of São Paulo, Brasil; 2 Departamento de Química da Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, University of São Paulo, Brasil. E-mail: [email protected] The discovery of metalo-drugs such as NAMI-A and KP1019 (both in clinical trials), has lead to the interest on ruthenium coordination complexes with potential biological activity. This interest is due to their good clinical application against metastatic cells and to their low systemic toxicity. In this context, the present work describes the results of synthesis and characterization of the compounds [Ru2O(carb)2(py)6] (PF6)2 (carb = ibuprofen (1) and ketoprofen (2); py = pyridine) and also a preliminary investigation of their possible biological activity by means of an experiment of in vitro metabolism using rat liver microsomes. The compounds were obtained by reacting stoichiometric amounts of RuCl3 and ibuprofen (or ketoprofen) under reflux for 10 minutes in a 3v: 1v mixture of water : ethanol, followed by 1 hour reflux with excess of pyridine and addition of NaPF6. Both compounds were purified by adsorption chromatography in neutral alumina columns, using mixtures of acetonitrile and dichloromethane as mobile phase. In the ESI – MS spectra, compounds presented peaks at m/z 1249 [1 – PF6]1+ and at m/z 1345 [2 – PF6]1+. Compounds 1 and 2 displayed typical absorption bands for the [Ru2O] class of complexes (for compound 1: MLCT at lmax = 326 nm, e = 14149 M-1cm-1 and MMCT at lmax = 586 nm, e = 7275 M-1 cm-1; for compound 2: MLCT at lmax = 328 nm, e = 14985 M-1cm-1 and MMCT at lmax = 586 nm, e = 5959 M-1cm-1) as well as a reversible electrochemical behavior probed by cyclic voltammetry (for compound 1 E1/2 at 1.00V and 0.41V (vs Ag/AgCl) ascribed to RuIVRuIV / RuIVRuIII / RuIIIRuIII; for compound 2 E1/2 at 1.01V and 0.36V (vs Ag/AgCl) ascribed to RuIVRuIV / RuIVRuIII / RuIIIRuIII). In both cases, the Dnas(COO-) – ns(COO-) falls in between 40 and 45 cm-1,

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MS.D1.P.580 Metal Based Antiparasitic Drugs: Synthesis, Analysis and Biological Potency. Joshua Obaleye*1, Adedibu Tella1, Elizabeth Balogun2, Olufemi Awotunde3, Joseph Adebayo2, Patricia Omojasola4, Gabriel Obiyenwa1, Nzikahyel. Simon5, Wahab Osunniran1, Mercy Bamigboye1 and Caroline Akinremi,6 1,2,3,4Department of Chemistry, University of Ilorin, Ilorin, Kwara State (Nigeria). 5Department of Chemistry, University of Uyo, Uyo, Akwa-Ibom State (Nigeria). 6Department of Chemistry, University of Agriculture Abeokuta, Ogun State (Nigeria). E-mail: [email protected]; [email protected] Parasitic diseases represent a major world health problem with very limited therapeutic options. Most of the available treatments of these diseases are decades old and suffering from limited efficacy and /or undesirable collateral effects. The applications of metal complexes as chemotherapeutic agents against these ailments appear as a very attractive alternative. Although the design of metal complexes with good therapeutic index is still rather empirical, more efforts are required to make available a number of potential metal-based antiparasitic drugs. There have also been worldwide agreements over the present need to develop novel antibacterial agents to treat infections that have become increasingly resistant to existing standard antibacterial therapies. The resistances have been proposed by experts to be due to mutations in the genes of bacterial targets of the broad spectrum antibiotics–the tetracyclines, quinolones fluoroquinolones, anti-TB drugs and many others. Chemical modifications of the existing anti-malarial and the antibacterial drugs through their coordination unto a metal ion centre for an enhanced efficacy has attracted much attention in recent years. The use of the knowledge of organometallic compounds in solving health problems has connection to the role of metal ions in almost all living organisms. It is worthwhile to know how some of these metal ions interact with the drugs ( in vivo and in vitro). Several reports on anti-malarial and anti-bacterial metal complexes with enhanced efficacy compared with the parent drug have abounded. In this direction, we have synthesized some metal complexes of lumefantrine –an antimalarial drug, eflornithine-an antitrypanosomiasis drug and other antibiotic drugs. The products were characterized using some physico-chemical properties and spectroscopic techniques: 1H and 13C NMR, IR, UV/Visible, Mass Spectrometry (MS). Some of these compounds were characterized by single Crystal X-ray analysis. Their biological potency will also be reported. [1]. I. Turel,. Coord. Chem. Rev. 2002, 232, 27-47 and reference therein. [2]. J.A. Obaleye, M.R. Caira and A.C. Tella, J. Chem. Crystallogr., 2007, 37: 707 – 712. and references therein. [3]. J. A. Obaleye; M.R. Caira; and A.C. Tella. Analytical Sciences. 2008, 24, 63-64.

Keywords: Antiparasitic, Characterisation, Potency

MS.D1.P.581

using 64,67Cu radioisotopes). The synthesis and characterization of the title ligands, their complexation behavior, as well as preliminary results on radioisotope complexation will be presented in details.

“Clickable” Lanthanide Complexes for Bioconjugation and the Preparation of Multi-Modal Imaging Agents William O’Malley,a Linda Tjioe,b Leone Spiccia,b Bim Grahama a Medicinal Chemistry and Drug Action, Monash University (Parkville Campus), VIC 3052, Australia. bSchool of Chemistry, Monash University, Clayton, Australia. E-mail: william.o’[email protected] Luminescent labels incorporating lanthanide metals have proved extremely useful within biological applications. Their large Stokes shift and very long fluorescent lifetimes are able to effectively eliminate (or drastically reduce) many of the issues associated with the use of more traditional organic fluorescent dyes, such as autofluorescence and cross-talk between excitation and emission wavelengths. These issues can lead to false positives during assays. Our work involves the preparation of a new series of lanthanide based tags featuring alkyne groups allowing for conjugation via click chemistry. The appeal of click chemistry is that the two functional groups involved, an azide and an alkyne are not found anywhere within biological systems, therefore no undesirable interactions can occur, allowing the tag to be very specifically directed towards to the targeted site. Within this work we plan to click a selection of the best performing complexes to azide-bearing proteins in order to demonstrate their sitespecific conjugation, and to iron nanoparticles in the development of new multimodal imaging agents. Keywords: lanthanide complexes, click chemistry, bioconjugation

MS.D1.P.582 Bifunctional Chelators for Selective Copper(II) Binding Monika Paúrová, Jan Kotek, Petr Hermann, Department of Inorganic Chemistry, Faculty of Science, Charles University in Prague. E-mail: [email protected] Two new bifunctional ligands derived from cyclam (1,4,8,11-tetraazacyclotetradecane) with two methylphosphinic acid or methylphosphonic acid pendant arms and p-aminobenzyl reactive side moiety were prepared, namely 4-methyl-11-(p-aminobenzyl)-1,4,8,11tetraazacyclotetradecane-1,8-bis(methylenephosphinic acid) and 4-methyl-11-(p-aminobenzyl)-1,4,8,11-tetraazacyclo-tetradecane-1,8bis(methylenephosphonic acid). Thermodynamic stability constants with selected transition metal ions were determined as well as kinetics of formation and acid dissociation of the copper(II) complexes. The results show that ligands mentioned above are ones of the most suitable for copper(II) complexation. The copper(II) complexes are stable (logbML = 18.3 and 23.2 for phosphinate and phosphonate derivatives, respectively) and are formed with a high selectivity over nickel(II) and zinc(II) complexation (for both metal ions, logbML are ~11 for the phosphinate and ~16 for the phosphonate derivatives, respectively). The copper(II) ion is quantitatively complexed above pH ~3.5 (cL = cM, milimolar range) The copper(II) complexes with both ligands are kinetically inert towards acid-assisted dissociation, with relatively long half-lives in strong acid media [e.g. ~47 s (phosphinate) and ~43 s (phosphonate) in 1 m HClO4 and at 25 °C]. Both ligands bind copper(II) ion very fast at pH ~4.5 where no complexation of zinc(II) and nickel(II) ions proceeds. These facts are very promising for use in radiochemistry (radioisotope purification) and radiomedicine (diagnosis and therapy

Keywords: cyclam, copper(II) complexes, nuclear medicine

MS.D1.P.584 Gadolinium(III)-Nitroxide Complexes as pH-sensitive MRI Contrast Agents with Enhanced Relaxivity Alex Recuenco,a Francisco M. Romero,a Alicia Nuez,a Carlos J. Gómez-García,a Robert N. Muller,b Luce Vander Elst,b Sophie Laurent.b aInstitute for Molecular Science, University of Valencia, Valencia, (Spain). bUniversity of Mons, Mons, (Belgium). E-mail: [email protected] Magnetic resonance imaging (MRI) is a powerful technique for a non-invasive study of biological tissues with high spatial resolution and contrast.[1] Very often, paramagnetic substances (contrast agents) are used to induce fast relaxation of the protons, giving rise to brighter well-resolved images. Most of the approved CA for clinical purposes are based on Gd(III) complexes. Gd3+ possesses a high electronic spin (S=7/2) with a very slow relaxation time. However, this metal ion is toxic and it has to be administered as a very stable metal complex to prevent dissociation in the body. Also, it is known that nitroxide radicals enhance the proton relaxation rate and could be applied in MRI. [2] Herein, we show two novel gadolinium (III) complexes of tetraazamacrocyclic ligands bearing a free radical pendant arm which exhibit higher relaxivities than commercially available MRI contrast agents together with marked pH-sensitivity that can be very important for their potential use in clinical diagnosis (Fig. 1).

Figure 1. Structure of tetraazamacrocyclic ligands. [1] a) Lauffer, R.B. Chem. Rev. 1987, 87, 901. b) Caravan, P.; Ellison, J.J.; McMurry, J.; Lauffer, R.B. Chem. Rev. 1999, 99, 2293. [2] a) Afzal, V.; Brasch, R.C.; Nitecki, D.E.; Wolff, S. Invest. Radiol. 1984, 19, 549. b) Francese, G.; Dunand, F.A.; Loosli, C.; Merbach, A.E.; Decurtins, S. Magn. Reson. Chem. 2003, 41, 81.

Keywords: MRI, gadolinium, nitroxide radicals

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Poster Sessions MS.D1.P.585 Towards Novel Stable Lanthanide(III) Complexes with Cyclam Derivatives Aurora Rodríguez-Rodríguez,a Andrés de Blas,a David EstebanGómez,a Carlos Platas-Iglesias,a Teresa Rodríguez-Blas,a aDepartmento de Química Fundamental, Universidade da Coruña, A Coruña (Spain). E-mail: [email protected]. Cyclams are 14-membered tetraazamacrocycles that may strongly bind to a wide range of metal ions, and can be used for different applications such as: (1) models for carrier molecules in studies of the selective uptake and transport of metal ions and oxygen in biological systems, (2) metal ion recovery through selective extraction, (3) active site mimics of metalloenzymes and metal catalysts, (4) agents for phosphate esters cleavage (including DNA and RNA), (5) production of radiopharmaceuticals for diagnosis and tumour therapy, or (6) preparation of anti-HIV agents.[1]

We are interested in the design of novel highly stable lanthanide(III) complexes with potential application in Molecular Imaging, particularly in Magnetic Resonance Imaging (MRI) and for optical probes. Herein we report the two new macrocyclic ligands L1 and L2 based on cyclam platforms, which contain picolinate pendant arms, and that have been designed for stable lanthanide(III) complexation in aqueous solution. Ligand L2 is a remarkably efficient proton sponge due to its ability to adopt low‑energy conformations having all four nitrogen lone pairs convergent upon a cleft. As a consequence, harsh conditions are required to synthetize the corresponding Ln(III) complexes in comparison to the L1 analogues. The X-ray crystal structures of several Ln(III) complexes with both ligands have been determined; likewise their structures in solution have been also investigated by using 1H and 13C NMR spectroscopy, as well as by theoretical calculations performed at the density functional theory level (TPSSh). The hydration numbers (q) determined from luminescence lifetime measurements in aqueous solution of the EuIII and TbIII complexes are also reported. [1] X. Liang, P.J. Sadler, Chem. Soc. Rev., 2004, 33, 246-266.

Keywords: cyclam, lanthanides, macrocycles

MS.D1.P.586 Gold Nanorods for Biomedical Applications Federica Scaletti,a Lara Massai,a Fulvio Ratto,b Sonia Centi,b Chiara Gabbiani,c Luigi Messori,a a Department of Chemistry, University of Florence, Sesto Fiorentino, (Italy). b Institute of Applied Physics “Nello Carrara”(IFAC), National Research Council (CNR), Sesto Fiorentino, (Italy). c Department of Chemistry and Industrial Chemistry, University of Pisa, Pisa, (Italy). E-mail: [email protected] Gold nanoparticles (GNP) have attracted a widespread attention due to their unique physicochemical properties; they exhibit tremendous potential for biomedical applications from the detection of protein/DNA interactions to drug delivery and cancer therapeutics and diagnostics. The interest of gold lies in its inert and nontoxic nature, controllable size and ease of functionalization with organic molecules

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tailored for specific purpose. In particular, gold nanorods (GNR) are attracting special attention due to their unique optical properties, which include a surface plasmon absorption band in the visible region and a second tunable absorption in the NIR, making them good agents for photothermal treatment of cancers. Previous studies, [1], [2], showed that GNRs exposed to biofluids become coated with proteins; adsorption of proteins on the GNR’s surface might have consequences on the characteristic conformation and cause a loss of biological activity or, in many cases, elicit altered immune response. Till now, little is known about the kinetic and thermodynamic stability of proteins that interact with GNRs. Therefore it would be useful to carry out a comparative study of GNRs stability in a biological buffer and specifically evaluate the interaction of GNRs of different size and surface chemistry with model proteins, like lysozyme, cytocrome c and bovine serum albumin (BSA). The various GNRs synthesized were functionalized with thiolated poly (ethylene glycol) (PEG) moieties, with different charged functional groups, or small molecules like 16-mercaptohexadecanoic acid that allow formation of a charged self-assembled monolayer (SAM) on GNR’s surface. Here we report the characterization of these systems, with the aid of dark-field microscopy (DFM), dynamic light scattering (DLS) and transmission electron microscopy (TEM) and the interaction with model proteins monitored through spectrophotometric analysis. Further modifications of GNR’s surface properties will be needed to enhance the tumor targeting; for this purpose it would be interesting to evaluate the cellular uptake, biodistribution and cytotoxic effect of these functionalized GNRs. The understanding of such interactions provides useful hints for the selection of promising products for biomedical application. [1] S. Chakraborty, P.Joshi, V. Shanker, Z. A. Ansari, S. P. Singh and P. Chakrabarti, Langmuir, 2011, 27, 7722-7731. [2] T. T. Moghadam, B. Ranjbar, K. Khajeh, S. M. Etezad, K. Khalifeh, M. R. Ganjalikhanyl, Int. J. of Biol. Macromol., 2011, 49, 629-636.

Keywords: Gold nanorods, protein-nanoparticle interactions, nanomaterials

MS.D1.P.587 Metallamacrocyclic complexes of Cu(II) and Zn(II) with 3,3,3′,3′-tetraaryl/alkyl-1,1′-isophthaloylbis(thiourea) Nagamani Selvakumarana, Annamalai Pratheepkumara, Ramasamy Karvembu,a* aDepartment of Chemistry, National Institute of Technology, Tiruchirappalli 620 015, India E-mail: [email protected] Ligands of general type RC(O)NHC(S)N(R′)2 are well known for their affinity for the softer transition metal ions and have been extensively studied as part of a program examining their potential uses in the platinum group metal (PGM) industry. For instance complexes of the corresponding mono-podal 3,3′-dialkyl-1aroylthioureas and 3,3′-dialkyl-1-acylthioureas have been used in solvent extraction, thin layer, and reversed-phase high-pressure liquid chromatographic separation of the platinum group metals. The bipodal derivatives with two S, O chelating moieties are best suitable for the synthesis of multinuclear complexes. Particularly, meta-substituted phthaloylbis(thiourea) ligands are able to form self assembled metallamacrocyclic complexes [1,2]. New complexes of the type M2L2 [H2L = 3,3,3′,3′-tetraaryl/alky-1,1′-isophthaloylbis(thiourea), M = Cu or Zn] have been prepared and characterized by analytical and spectral (electronic, FT-IR, 1H, 13C NMR, mass) techniques. The molecular structure of Cu2(L)2 has been determined by single crystal X-ray diffraction analysis. Cytotoxic studies have also been carried out for these complexes.

[1] K.R. Koch, S.A. Bourne, A. Coetzee, J. Miller, J. Chem. Soc., Dalton Trans. 1999, 634, 867. [2] S.A. Bourne, O. Hallale, K.R. Koch, Cryst. Growth Des. 2005, 5, 307.

Keywords. Macrocyclic complexes, Copper(II), Zinc(II)

MS.D1.P.588 Identification of Carbon Coated Iron Oxide Nanoparticles in Ayurvedic Drug: Loha Bhasma R. W. Jawalea, P. K. Khannab, B.A.Kulkarnic, Rupali Ladc, Mrudula Wadekarc,Vividha Dhapted and S. S. Kadam,d aCollege of Engineering. Bharati Vidyapeeth Deemed University Pune 411039, bDIAT, Girinagar, Pune 411 025 (India), cY. M. College, Bharati Vidyapeeth Deemed University, Pune-411 038, dPoona College of Pharmacy, Paud Road, Pune-411 038. E.mail : [email protected] The rapid growth of developments in nanoscience and nanotechnology have revolutionary impacts on all most all branches of science. Chemistry of drugs and medicines is one of such branches related to human health in which nanomedicines and nano-drugs occupy top-most position due to their unique merits and advantages. Ayurvedic system of medicine is one of the most ancient systems of medicines of Indian origin, which includes an important class of drugs of mineral origin. Among these, drugs derived from gold, silver, copper, iron, tin, lead and zinc are of special interest. These are synthesized by following traditional ayurvedic processes called as bhasmikarana, which involves transformation of macrometallic state into micro or nano bhasma state. Extraordinary medicinal properties are claimed to be induced in this bhasma state including the loss of toxicity of the heavy metals. During our extensive and intensive work on the metal-based ayurvedic drugs of the above-referred seven metals, we have realized that, if the art and science of these drugs is reinvestigated in the light of modern scientific developments, these drugs will be proved to be very useful, unique and acceptable as approved drugs. Our present attempts are in this direction. In an attempt to search the origin of the significant medicinal properties induced in these drugs, it was found that two factors are likely to be attributable to this change (a) incorporation of an organic component into the tiny bhasma particles through their intimate interactions with plant juices during trituration in an agate mortar (b) reduction of the particle size to nano level by repeated calcinations of the triturated matter through traditional ayurvedic technique. This conclusion is supported by our studies on the metallic bhasmas derived

from gold; copper; iron and tin, whose chemical and structural aspects are elucidated through E.DAX; SEM; XRD; XPS and IR Spectroscopy. In this communication, we would like to report our recent work on iron-based ayurved drug, loha bhasma. This loha bhasma is synthesized from pure metallic iron powder by following the traditional process of bhasmikarana prescribed in the standard ayurvedic texts, which is followed in India since past several years. Among the various methods currently used for the synthesis of loha bhasma, methods which, make use of cow-urine, trifala (i.e. fruits of three medicinal plants) extract and plant juices or aqueous extracts of selected medicinal plants are well established. In the present work, use of an important medicinal plant known as Kanchanar (Bauhinia variegato) is made. No any other toxic materials like mercury, HgS or arsenic sulfides are used to avoid contamination of any toxic matter. The resulting loha bhasma is dark-brown in colour, the major constituents of which are iron, oxygen and carbon along with a number of minor and trace constituents. All the constituents other than iron are introduced through the process of bhasmikarana. Identification of carbon-coated iron-oxide nano particles (size 39.7 nm) is done through XRD, EDAX, SEM and XPS. Keywords: iron oxide nanoparticles, ayurvedic drug loha bhasma

MS.D1.P.589 Antitumor Platinum(II) Complexes with 7-Azaindole Halogeno Derivatives Pavel Štarha,a Zdeněk Trávníček,a Alexandr Popa,a Igor Popa,a Radim Vrzal,b aRegional Centre of Advanced Technologies and Materials, Department of Inorganic Chemistry, Palacký University, Olomouc (Czech Republic). bDepartment of Cell Biology and Genetics, Palacký University, Olomouc (Czech Republic). E-mail: [email protected] The platinum-based complexes cisplatin, carboplatin and oxaliplatin are world-wide used anticancer metallotherapeutics. However, their clinical application is connected with several problems, such as negative side effects (e.g. nephrotoxicity, neurotoxicity, myelosuppression) or resistance of some types of tumors. That is why the research of platinum, as well as other transition metals, complexes with high antitumor effect and reduced negative properties is one of the main orientations of modern bioinorganic chemistry. The cis-[PtCl2(L)2] and [Pt(ox)(L)2] platinum(II) complexes involving various halogeno (chloro, bromo, iodo) derivatives of 7‑azaindole were prepared and thoroughly characterized by means of elemental analysis, IR, Raman and multinuclear (1H, 13C, 15N and 195Pt) and two dimensional (1H–1H gs-COSY, 1H–13C gs‑HMQC, 1H–13C gsHMBC and 1H–15N gs-HMBC) NMR spectroscopy and a single crystal X-ray analysis; ox = oxalate dianion. The complexes were studied for their in vitro antitumor activity against ovarian carcinoma A2780, cisplatin-resistant ovarian carcinoma A2780R, malignant melanoma G361, breast adenocarcinoma MCF7, lung carcinoma A549, osteosarcoma HOS, cervix carcinoma HeLa and prostate carcinoma LNCaP human cancer cell lines. The dichlorido complexes showed in most cases significantly higher in vitro cytotoxicity (p < 0.05) against the mentioned cells, as compared with cisplatin. For example, IC50 values of the most active complex with 5-bromo-7‑azaindole (5BrL) is depicted in Fig. 1. The obtained results showed that the prepared complexes are highly in vitro antitumor effective against a broad spectrum of human cancer cells and these substances avoid the cisplatin resistance of ovarian carcinoma. The mechanism of action of these compounds will be further studied by the modern molecular pharmacology methods.

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Figure 1: A structural formula and antitumor activity (given as IC50 values in µM) of cis‑[PtCl2(5BrL)2] against eight human cancer cell lines and its comparison with cisplatin

The research was supported by the projects P207/11/0841, CZ.1.05/2.1.00/03.0058, CZ.1.07/2.3.00/20.0017 and PrF_2012_009). Keywords: platinum, 7-azaindole, antitumor activity

MS.D1.P.590

[1] G. Gasser, L. Tjioe, B. Graham, M. J. Belousoff, S. Juran, M. Walther, J.-U. Künstler, R. Bergmann, H. Stephan, L. Spiccia, Bioconjugate Chem. 2008, 9, 719-730.

Keywords: copper(II), bioconjugation, radiolabeling

MS.D1.P.591

TACN-derived Ligands as Highly Stable Biofunctionalizable Chelators For Copper(II) Holger Stephan,a Julia Hesse,a Alexander Ruffani,a Katrin Viehweger,a Jörg Steinbach,a aInstitute of Radiopharmacy, Helmholtz-Zentrum Dresden-Rossendorf, D-01314 Dresden, (Germany). E-mail: [email protected]

Phosphorus Esters Hydrolysis Stabilization by Ruthenium(II) Daniela Ramos Truzzi,a Douglas Wagner Franco,a aInstitute of Chemistry of São Carlos, Department of Chemistry and Physics Molecular, University of São Paulo, São Paulo (Brazil). E-mail: [email protected]

The tridentate macrocycle 1,4,7-triazacyclononane (TACN) forms stable complexes especially with Cu(II) whereby the metal ion lying out of the plane defined by the three nitrogen atoms. The donor atoms are oriented in such a way as to maximize orbital overlap and thereby produce complexes with very high stabilities. The introduction of further donor groups on the ligand skeleton, such as pyridine units, significantly influences the thermodynamic stability as well as the kinetic inertness of the metal complexes formed. We have developed a ligand scaffold based on bis(2-pyridylmethyl)triazacyclononane (DMPTACN) [1]. This structure allows for the introduction of linker groups, such as carboxylic acids, maleimide or isothiocyanate, thereby facilitating coupling of targeting molecules (see Figure). TACN ligands containing one or two pendant 2-picolyl arms prefer the formation of square-pyramidal coordination geometry with copper(II). A hexadentate ligand with two picoline coordination groups as well as a carboxylic functionality (DMPTACN-COOH) enforces a six-coordinate copper(II) complex having a distorted octahedral structure. It has been found that relevant peptide conjugates of this hexadentate bis(2-pyridylmethyl)-TACN-acetic acid derivative can readily form radiocopper complexes under physiologically relevant conditions and show high in vivo stability. Such radiolabeled peptides are thus attractive candidates for radiopharmaceutical applications. We want to present the synthesis of peptide conjugates with DMPTACN derivatives capable of gastrin releasing peptide receptor (GRPR) and epidermal growth factor receptor (EGFR) targeting. Both types of receptors are overexpressed on different cancer cells. In vitro binding characteristics of [64Cu]CuII-labeled DMPTACNpeptide conjugates in GRPR and EGFR overexpressing cancer cells (PC-3, FaDu, A431) will be presented. Small animal PET studies confirmed a high extent of tumor accumulation in NMRI nu/nu mice bearing the human prostate tumor PC-3. Derived from that, it can be concluded that 64CuII complexes of DMPTACN-peptide conjugates have considerable potential for tumor imaging, since these peptide derivatives can effectively display receptor-rich tissue in vivo.

Phosphorus esters are very important in industrial processes. Due to their strong trans-effect and trans-influence are used on tailoring catalysts and metallopharmaceuticals. On this last aspect there is a particular concern regarding to the ruthenium nitrosyl complexes [1]. On such species the coordination to ruthenium(II) center leads to substantial changes on the metal center and on the phosphorus ligand proprieties. Aiming to better understand this mutual influence, the hydrolysis of free and coordinated P(OH)(OEt)2 in [Ru(H2O)(NH3)4]2+ and [Ru(NO)(NH3)4]2+ moieties and of the complex t-[Ru(NO) (NH3)4P(OEt)3]3+ have been monitored trough spectroscopic (IR and NMR) and electrochemical (CV and DPP) methods. According to Table 1 data, the rate for the ethyl group hydrolysis decreases as follows: P(OH)(OEt)2 > t-[Ru(NO)(NH3)4P(OEt)3]3+ > t-[Ru(NO)(NH3)4P(OH)(OEt)2]3+ > t-[Ru(H2O)(NH3)4P(OH)(OEt)2]2+. This trend can be explained on terms of the Ru(II)èP(III) back-bonding which would increase the electron density over the a-carbon at the ethyl group of the phosphorus ligand and thus resulting in the ligand stabilization toward hydrolysis. According to DFT calculations, in nitrosyl complexes this stabilization is smaller than in the aquo species due to the strong p-acceptor character of NO+ which would compete for the Ru(II) 4dp electrons decreasing the electronic density in the phosphite ligand. As judged by infrared and 31 P NMR data, the ion t-[Ru(NO)(NH3)4P(OEt)3]3+ (d = 80 ppm, nNO+ = 1920 cm-1, ENO+/NO0 = -0.24 V vs SCE) hydrolysis yields as a product only t-[Ru(NO)(NH3)4P(OH)(OEt)2]3+ (d = 68 ppm, nNO+ = 1887 cm-1, ENO+/NO0 = -0.50 V vs SCE). This last species decay is the rate determining step of the reaction which yields mostly free diethyl phosphite and its hydrolysis products (12-0 ppm). In this step, the P(OH)(OEt)2 ligand hydrolysis is not the main process, but the phosphorus ester aquation instead. During the course of the reaction besides these signals at 68 and 12-0 ppm, other two peaks of low intensity (less than 8% of the total phosphorus signals) were also observed; one at 66 ppm attributed t-[Ru(NO)(NH3)4P(OEt)(OH)2]3+ and other at 62 ppm attributed tentatively to t-[Ru(NO)(NH3)4(O)P(OH)(OEt)]2+ species.

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P(OH)(OEt)2

7.1×10-6

27.0

E (V) vs SCE -

t-[Ru(H2O)(NH3)4P(OH) (OEt)2]2+ t-[Ru(NO)(NH3)4P(OH) (OEt)2]3+ t-[Ru(NO)(NH3)4P(OEt)3]3+

-7

4.8×10

403.2

0.29

8.9×10-7

216.0

-0.50b

1920

2.9×10-6

67.2

-0.10 b

1887

k (s-1)

t1/2 (h)

a

nNO (cm-1) +

-

Constants measured at pH 3.0 and 25°C; Ru /Ru ; NO /NO . a

III

II b

+

0

An isomerization and coordination trough oxygen atom would occur after the ethyl group hydrolysis on t-[Ru(NO)(NH3)4P(OH)(OEt)2]3+. Structural changes on phosphite ligand can lead to considerable changes on ENO+/NO0, nNO+ and also on the complex robustness which could be useful on tailoring new complexes. [1] D. R. Truzzi, A. G. Ferreira, S. C. Silva, E. E. Castellano, F. C. A. Lima, D. W. Franco, Dalton Trans, 2011, 40, 12917-12925. Keywords: nitrosyl complexes, phosphorus esters, ruthenium

MS.D1.P.592 Development of Bis(Tridentate) Ruthenium (II) Polypyridyl Complexes for Biological Applications Solmaz Tubafard, Leone Spiccia, School of Chemistry, Monash University, Clayton, Victoria 3800,(Australia). E-mail: solmaz. [email protected] Ruthenium complexes are considered ideal for different biomedical purposes due to their photochemical and electrochemical properties. In this context, tuning of the ligands environment can have a significant effect on the binding and spectroscopic properties of ruthenium complexes [1]. Several strategies to improve the utility of such complexes have been reported which seek to increase the excitedstate lifetimes, of which a few approaches have specifically been aimed at destabilizing the MC states [2]. These include utilizing either strong-field cyclometalating ligands or 2,6-diquinolin-8-ylpyridine (dqp) ligands, [3,4] to tune wavelength and intensity of maximum luminescent emissions. Cyclometalated ruthenium complexes generally exhibit broader and red-shifted visible absorption in comparison to the analogous [Ru(N^N^N)2] complexes, which could make them useful for in vivo applications. Moreover, cyclometalation itself has a strong effect on the photophysical properties of the complexes [5]. We report on our recent investigations into the design and synthesis of polypyridyl and cyclometalated ruthenium(II) complexes with desirable spectroscopic and electrochemical properties intended for applications as sensors for particular DNA or RNA targets when combined with PNA oligomers via peptide coupling procedures. [1] A. Anthonysamy, S. Balasubramanian, V. Shanmugaiah, N. Mathivanan, Dalton, 2008, 16,2136. [2] E. A. Medlycott, G. S. Hanan, Coord Chem. Rev, 2006, 250, 1763–1782. [3] M. Abrahamsson, M. Jager, T. Osterman, L. Eriksson, P. Persson, H. C. Becker, O. Johansson, L. Hammarstrom, J Am Chem Soc, 2006, 128, 12616–12617. [4] M. Jager, L. Eriksson, J. Bergquist, O. J. Johansson, Org Chem, 2007, 72, 10227–10230. [5] T. A. Koizumi, T. Tomon, K. J. Tanaka, Organomet Chem, 2005, 690, 4272–4279.

MS.D1.P.593 Metal Tetrazolato Complexes for Applications in Biological Imaging Melissa Werrett,a Massimiliano Massi,a David H. Brown,a Luis Filgueira,b Brian Skelton,c Paul Rigby,c Stefano Stagni,d Sara Muzzioli,d a Department of Chemistry, Curtin University, Perth (Western Australia), b Department of Anatomy and Human Biology and cCMCA, The University of Western Australia, Perth (Western Austrlaia), dDepartment of Physical and Inorganic Chemistry, University of Bologna, Bologna, (Italy) E-mail: [email protected] Cellular imaging using contrast agents that exhibit luminescence offers a rapid way to visualise biological tissue at a subcellular level. The most common probes developed for biological imaging are highly conjugated organic molecules.[1] These fluorescent probes are available commercially[2] however in many cases, their non-optimised photophysical properties can mean a loss in image quality and resolution, leading to poor diagnostic output.[3] Phosphorescent metal complexes on the other hand have been less investigated in this field but provide advantageous photophysical and chemical properties.[4] A series of fac-rhenium tricarbonyl bisimine complexes have been prepared and fully characterised through NMR, IR and X-ray crystallography. The chosen ancillary ligand is a para substituted 5-aryltetrazole which shows to coordinate to the rhenium via the N2 atom. These complexes exhibit phosphoresent emission with t ≈ 280357 ns and F ≈ 0.022-0.032.[5] Preliminary biological studies in vitro were carried out on a range of healthy and cancer cell lines. Extracellular staining using a fluoroesently labelled protien, combined with z-stack confocal imaging, revealed that the complex was taken into cells. Co-localistion studies revealed apparent mitochondrial localisation. The localisation was cross-checked by co-staining the cell cultures with nuclear and mitochondrial stains. Based on this, photophysical investiagation was undertaken to determine if the species emitting from within the cell had been altered in any way. There is no obvious detectable change occuring to the rhenium complexes upon incuation and uptake into cells. The rhenium labels also show low toxicity levels, assessed with the MTS test and exhibit high resistance to photobleaching.

All complexes gave similar crystal structures, showing the N2 linkage isomer.

[1] Q. Zhao, M. Yu, L. Shi, S. Liu, C. Li, M. Shi, Z. Zhou, C. Huang and F. Li, Organometallics, 2010, 29, 1085-1091. [2] E. M. Goldys, ed., Fluorescence Applications in Biotechnology and the Life Sciences, Wiley-Blackwell, New Jersey, 2009. [3] V. Fernandez-Moreira, F. L. Thorp-Greenwood and M. P. Coogan, Chem. Commun., 2010, 46, 186-202 [4] S. Pandya, J. H. Yu and D. Parker, Dalton Transactions, 2006, 2757-2766. [5] M. V. Werrett, D. Chartrand, J. D. Gale, G. S. Hanan, J. G. MacLellan, M. Massi, S. Muzzioli, P. Raiteri, B. W. Skelton, M. Silberstein and S. Stagni, Inorg. Chem., 2011, 50, 1229-1241.

Keywords: rhenium, luminescence, bioimaging

Keywords: ruthenium, complex, cyclometalation

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Table 1. Rate constants, spectroscopic and electrochemical data for selected phosphite compounds

Poster Sessions MS.D1.P.594

MS.D1.P.595

Effects of Glycoconjugated Pt and Pd Complexes Against Cisplatin-Resistant Cells Shigenobu Yano,a,b Mamoru Tanaka,c Hiromi Kataoka,c Takashi Joh,c Keisuke Kawamoto,d Takashi Shibahara,d Keiko Morimoto,e Michael Gottschaldt,f Ulrich S. Schubert,f aGraduate School of Materials Science, Nara Institute of Science and Technology, Nara, (Japan). b Office of Society-Academia Collaboration for Innovation, Kyoto University, Kyoto, (Japan). cDepartments of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Sciences, Nagoya, (Japan). dDepartment of Chemistry, Okayama University of Science, Okayama, (Japan). eDepartment of Health Science and the Clothing Environment, Nara Women’s University, Nara, (Japan). fLaboratory for Organic and Macromolecular Chemistry, Friedrich-Schiller-University Jena, Jena, (Germany). E-mail: [email protected]

Bifunctional Macrocyclic Chelators for Metals in Medicinal Imaging Marie-Caline Z. Abadjian,a Douglas B. Grotjahn,a Raghvendra Sengar,b Erik C. Wiener,b Riccardo Ferdani,c Carolyn J. Anderson,c aDepartment of Chemistry and Biochemistry, San Diego State University, San Diego, CA 92182 (United State). bDepartment of Radiology, University of Pittsburgh, Pittsburgh, PA 15213 (United States). cDepartment of Radiology, University of Pittsburgh, Pittsburgh, PA 15219 (United States). E-mail: [email protected]

Cancer is a leading cause of death worldwide, and according to the WHO mortality database (as at November 2006), gastric cancer is the second leading cause of cancer death after lung cancer. Cisplatin (CDDP) is the most frequently used chemotherapeutic agent for various types of advanced cancer including gastric cancer. Some CDDP based combination chemotherapy regimens have also shown high response rates. However, they have several disadvantages including side effects such as nephrotoxicity, neurotoxicity, ototoxicity and vomiting. In addition, almost all cancer cells acquire the resistance against CDDP, and this phenomenon is one of the causes that disturb vital prognosis. Thus, new chemotherapeutic agent that can overcome the CDDPresistance of cancer cells might make a great contribution for the survival of advanced cancer patients. Cancer cells take in higher levels of glucose than normal cells, a phenomenon known as the Warburg effect [1]. In this study, we synthesized and characterized new glycoconjugated platinum (II) and Palladium (II) complexes ; [MCl2 (L)] (M = Pt, Pd. L denotes 2-deoxy-2-[(2-pyridinylmethylene)amino]-a-D-glucopyranose), by elemental analysis, 1H and 13C NMR, and MS spectroscopy including X-ray crystallography, and analyzed the cytotoxicity and apoptosis induction ability to CDDP-sensitive and CDDP-resistant gastric cancer cell lines. The CDDP-resistant gastric cancers were established by continuous exposure to CDDP. Gene expression in the CDDPresistant gastric cancer cells was analyzed by real-time PCR arrays. To examine the cytotoxicity and apoptosis induction ability of [PtCl2 (L)] and [PdCl2 (L)] in the CDDP-sensitive or CDDP-resistant gastric cancer, proliferation assay and apoptosis assay were performed. Xenograft tumor mouse models were established and antitumor effects were also examined in vivo. The CDDP-resistant gastric cancer cells disclose ABCB1 and CDKN2A genes up-regulation compared with the CDDP-sensitive gastric cancer cells. [PtCl2 (L)] and [PdCl2 (L)] showed significantly high cytotoxicity for the CDDP-sensitive gastric cancer and executed their biological effects by inducing apoptosis. In the analyses of CDDP-resistant gastric cancer cells, [PdCl2 (L)] overcame cross-resistance to CDDP in vitro and in vivo, although [PtCl2 (L)] showed cross-resistance to CDDP-resistant gastric cancer. These results indicate that [PdCl2 (L)] is a newly developed potent chemotherapeutic agent for CDDP-resistant gastric cancer and is expected to have clinical applications. [1] O. Warburg, Science, 1956, 123 (3191), 309–314.

Keywords: Anti-cancer, Cisplatin-Resistant, Glycoconjugated Complex

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Coupling imaging agents, magnetic resonance imaging (MRI) or positron emission tomography (PET), to targeting molecules have the potential to be used in theranostics. These bifunctional compounds have advantageous capabilities of acting as an imaging tool as well as an agent for targeted radiotherapy or in the case of nanoparticles, a drug delivery vehicle for a cytotoxic agent. Such compounds like bifunctional macrocyclic chelators are attractive synthetically and in medicinal applications. This work concentrates on the synthesis of bifunctional MRI agents and bifunctional PET tracers and their complexation to metals of interest. Copper-catalyzed azide-alkyne cycloaddition (CuAAC) is used to form a triazole linkage between the imaging agent and the targeting compound of interest will be discussed. In this presentation, MRI contrast agents are designed to enhance T1 relaxivity by coupling them to synthetically controlled dendrimers. Cyclen is used as a starting scaffold for the synthesis of bifunctional Gd-DOTA and Gd-DOTMA analogues. A unique side chain on the macrocycle contains an azide moiety can be clicked to an alkynecontaining core, making the first generation of dendrimer with the potential to improve MRI relativity. The PET tracers are designed to specifically coordinate 64Cu, a positron source, while containing clickable side arms. A functionalized cross-bridge tetraazamacrocycle with two identical azide-bearing side arms can be clicked to alkynyl amino acid, which provides several advantages with respect to applications. The bifunctional chelators not only provide a stable coordination pocket for the metal of interest but also a unique side chain/s for further coupling. Keywords: MRI contrast agents, PET tracers, click chemistry

MS.D1-P-596 Metal Complexes as Receptors for Pattern Based Recognition of Phosphatidylinositol Phosphates Hamasseh Behjat, Rudiger Woscholski, Ramon Vilar*. Department of Chemistry and Institute of Chemical Biology, Imperial College London, South Kensington Campus, London SW7 2AZ. Email: [email protected]; [email protected] Over the past few decades anion recognition has recieved a considerable amount of interest partly due to the important roles anions play in living organisms[1]. Phosphatidylinositol phosphates (PIPs) for example, are one type of anionic species which are involved in many cellular processes including cell signalling, cell proliferation and cell death[2,3]. Eight PIPs (see Figure below for an example) have been identified in living organisms and their functions are determined by the number and position of phosphate groups. Therefore, there is current interest in developing molecular tools capable of recognising each one of these PIPs to gain a better understanding of their function in vivo as well as with the aim of interfering with their biological functions for therapeutic purposes[4]. This project focuses on the development of an array of small metallo-receptors for the use in pattern based recognition enabling the

Poster Sessions

Figure: On the left an two examples of the mettalo receptors used within the array. PI(3)P is displayed on the right as an example of the structure of PIPs. [1] H. T. Ngo, X. Liu and K. A. Jolliffe, Chem. Soc. Rev., 2012, 41, 4928– 4965. [2] M.A. Lemmon, Traffic, 2003, 4, 201-213. [3] C. D’Souza-Schorey and P. Chavrier, Nature, 7, 2006, 347-358. [4] L. Hang Mak, S.N. Georgiades, E.Rosivatz, G.F. Whyte, M. Mirabelli, R. Vilar, and R. Woscholski, ACS.Chem. Biol. 2011, 6, 1382-1390. [5] B. E. Collins and E. V. Anslyn Chem. Eur. J. 2007, 13, 4700 – 4708. [6] S. Rochat, J. Gao, X. Qian, F. Zaubitzer, K. Severin, Chem. Eur. J. 2010, 16, 104 – 113.

MS.D2.P.597 Synthesis, Spectral Characterization, DNA Binding Ability and Antibacterial Screening of Copper(II) Complexes of NOON Tetradentate Schiff Bases Bearing Different Bridges Ayman A. Abdel Aziz, Saleh O. Bahaffi, Maher M. Elnagar, Department of Chemistry, Faculty of Science, Tabuk University, Tabuk, 71421, K.S.A. E-mail: [email protected] A novel series of four- copper complexes were synthesized by thermal reaction of copper acetate salt with tetradentate Schiff bases, N,N/bis(o-vanillin)4,5-dimethy-l,2-phenylenediamine (H2L1), N,N/ bis(salicylaldehyde)4,5-dimethyl-1,2-phenylenediamine (H2L2), N,N/ bis(o-vanillin)4,5-dichloro-1,2-phenylenediamine (H2L3) and N,N/ bis(salicylaldehyde)4,5-dichloro-1,2-phenylenediamine (H2L4), respectively. All the new synthesized complexes were characterized by using of microanalysis, FT-IR, UV-Vis., mass spectrometry, magnetic measurements, ESR, and conductance measurements, respectively. The data revealed that H2L1-4 coordinate in their deprotonated forms and behave as tetradentate NOON coordinated ligands and their copper complexes to have square planar geometry with general formula [CuL1-4]. The binding of the complexes with calf thymus DNA (CT-DNA) was investigated by absorption, luminescence titrations and viscosity measurements. The intrinsic binding constant (Kb) value determined from absorption studies were 4.754x104 M-1 for 1, 4.257x104 M-1 for 2, 3.637104 M-1 for 3, and 2.144 x104 M-1 for 4 respectively, revealing that 1 ˃ 3 ˃ 2 ˃ 4 in binding to CT-DNA. The order of binding of the complexes with CT-DNA was further supported by determination of the Stern-Volmer constant (KSV) from fluorescence studies. KSV values for the copper(II) complexes were found to be 1.95, 1.57, 1.05 and 0.96 respectively. The results indicated that the complexes bind to CT-DNA through an intercalative mode. The Schiff bases and their complexes were screened for their in-vitro antibacterial activity

against the bacterial species Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Pseudomonas aeruginosai by well diffusion method. The complexes showed an increased activity in comparison to some known antibiotics. Keywords: Cu(II) complexes, NOON donors, CT-DNA binding

MS.D2.P.598 DNA Binding Structure of Trinuclear Metal Complexes of Dipicolylamine Tethered to Salen Type Cu(II) Schiff Bases Makoto Chikira,a Akiyoshi Asahina, a Yusuke Kitamura, b, aDepartment of Applied Chemistry, Chuo University, Tokyo (Japan), bDepartment of Applied Chemistry and Biochemistry, Kumamoto University, Kumamoto, (Japan). E-mail: [email protected] The interactions of DNA and metal complexes have been the subject of intense investigations not only for the development of anticancer drugs and artificial restriction enzymes but also for the designs of functional DNA nano-materials. Among the various metal complexes, multinuclear metal complexes have attracted much attention by the synergistic effects expected between the metal centers, increasing the efficiency of the oxidative or hydrolytic DNA cleavage reactions. We have reported that the oxidative DNA cleavage activity of the trinuclear Cu(II) complexes (Fig. 1, M1 = M2 = Cu) is much higher than that of the mononuclear complex 1 and the activity increased in the order 1