Z. Kristallogr. NCS 230 (2015) 95-96 / DOI 10.1515/ncrs-2014-9008
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Crystal structure of bis(imidazolium) para-toluenesulfonate, C20H22N4O6S2 Puleng Moleko, Zenixole R. Tshentu, Eric C. Hosten and Richard Betz* Nelson Mandela Metropolitan University, Summerstrand Campus, Department of Chemistry, University Way, Summerstrand, PO Box 77000, Port Elizabeth 6031, South Africa Received July 24, 2014, accepted March 13, 2015, available online March 19, 2015, CCDC no. 1267/4278
(N–H 0.88 Å) and were included in the refinement in the riding model approximation, with Uiso(H) set to 1.2Ueq(N). Discussion
Abstract C20H22N4O6S2, triclinic, P1 (no. 2), a = 6.2648(2) Å, b = 6.3227(2) Å, c = 14.0946(6) Å, * = 85.051(2)°, ' = 79.288(2)°, # = 84.823(1)°, V = 544.9 Å3, Z = 1, Rgt(F) = 0.0317, wRref(F2) = 0.0896, T = 200 K. Table 1. Data collection and handling. Crystal: Wavelength: -: Diffractometer, scan mode: 2+max: N(hkl)measured, N(hkl)unique: Criterion for Iobs, N(hkl)gt: N(param)refined: Programs:
brown blocks, size 0.288$0.442$0.48 mm Mo K, radiation (0.71073 Å) 2.90 cm)1 Bruker APEX-II CCD, ! and " 56.6° 9620, 2688 Iobs > 2 &(Iobs), 2500 147 SHELX, WinGX, MERCURY, PLATON [10–13]
Source of material The compound was prepared upon reacting the neutral nitrogencontaining compound with iron(III)-para-toluenesulfonatehexahydrate in methanol. Crystals suitable for the diffraction study were obtained upon evaporation of the solvent at ambient conditions. Experimental details Carbon-bound H atoms were placed in calculated positions (C–H 0.95 Å) and were included in the refinement in the riding model approximation, with Uiso(H) set to 1.2Ueq(C). The H atoms of the methyl group were allowed to rotate with a fixed angle around the C–C bond to best fit the experimental electron density (HFIX 137 in the SHELX program suite [10]), with Uiso(H) set to 1.5Ueq(C). Nitrogen-bound H atoms were placed in calculated positions _____________
* Correspondence author (e-mail:
[email protected])
Perfluorinated hydrocarbons ionic liquids have attracted much attention as versatile reaction media over the past decades. A prerequisite for the suitability of a salt to act as ionic liquid is its low melting point that is conveniently achieved by the introduction of long perfluoroalkyl alkyl chains into simple nitrogen-containing organic moieties and crystallizing the resulting cations by means of bulkier anions such as tosylate [1]. In our continued interest in creating simpler derivatives of nitrogen compounds that might act as ionic liquids [2] motivated us to synthesize the title compound and elucidate its crystal structure by means of a diffraction study. Examples of imidazolium-based sulfonates have been characterized structurally before [3–5]. The title compound is the para-toluene-sulfonate salt of bisimidazole. The asymmetric unit contains half a cation and a complete anion. The least-squares planes as defined by the non-hydrogen atoms of the two heterocyclic moieties, respectively the phenyl group on the one hand and one of the heterocy-clic rings on the other hand, intersect at an angle of 84.48(4)°. Intracyclic angles in the cation span a range of 106.93(11)–108.99(11)° with the smallest angle found on one of the "terminal" carbon atoms and the largest angle on one of the nitrogen atoms. The S–O bond lengths are measured in between 1.4355(10)–1.4738(11) Å with the shortest bond length observed for the oxygen atom that does not participate in any intermolecu-lar contacts (vide infra). In comparison to other tosylates whose metrical parameters have been deposited with the Cambridge Structural Database [6], these values are in good agreement with the most common ones observed. In the crystal, classical hydrogen bonds of the N–H---O type are observed next to C–H---O contacts whose range invariably falls below the sum of van-der-Waals radii of the atoms participating in them [7]. The classical hydrogen bonds involve all NH groups as donors and are directed towards two different oxygen atoms of the tosylate anion as acceptors. The C–H---O contacts are supported by one of the CH groups of the cation and – exclusively – only have one of the two oxygen atoms as acceptors that is also engaged in the classical hydrogen bonds, i.e. one of the tosylate's oxygen atoms does not participate in any hydrogen-atom-involving contacts at all. In terms of graph-set analysis [8, 9], the descriptor for the classical hydrogen bond is R22(9) on both sides of the cation linking two adjacent anions. The C–H---O contacts necessitate a D descriptor on the same level only. In total, the entities of the title compound are connected to chains along [110] in the crystal. Additionally, two C–H---, interactions can be observed that stem from hydrogen atoms on the cation as well as the anion and, invariably, have the aromatic system of the tosylate anion as acceptor. The shortest
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96
C20H22N4O6S2
intercentroid distance between two centers of gravity was measured at 3.7830(8) Å and is apparent in between two of the heterocyclic ring systems.
Table 2. continued. Atom
Site
Table 2. Atomic coordinates and displacement parameters (in Å2).
H(3) H(12) H(13) H(15) H(16) H(17A) H(17B) H(17C)
2i 2i 2i 2i 2i 2i 2i 2i
Atom
Site
H(1) H(2) H(2A)
2i 2i 2i
x 0.2941 )0.2846 0.2050
y
z
Uiso
0.6961 0.6124 0.9730
0.4790 0.6139 0.5942
0.028 0.030 0.034
x )0.1688 0.2860 0.1197 0.5626 0.7309 0.2873 0.2104 0.0594
y 0.9168 0.6434 0.8851 1.3059 1.0669 1.2746 1.4230 1.2441
z
Uiso
0.6827 0.2118 0.1082 0.1163 0.2200 )0.0292 0.0592 0.0418
0.035 0.034 0.041 0.042 0.036 0.078 0.078 0.078
U13
U23
Table 3. Atomic coordinates and displacement parameters (in Å2). Atom
Site
S(1) O(1) O(2) O(3) N(1) N(2) C(1) C(2) C(3) C(11) C(12) C(13) C(14) C(15) C(16) C(17)
2i 2i 2i 2i 2i 2i 2i 2i 2i 2i 2i 2i 2i 2i 2i 2i
x 0.63623(5) 0.5568(2) 0.5463(2) 0.8690(2) 0.1697(2) )0.1566(2) 0.0028(2) 0.1159(2) )0.0879(2) 0.5225(2) 0.3418(2) 0.2435(2) 0.3227(3) 0.5055(3) 0.6061(2) 0.2100(4)
y
z
U11
U22
U33
0.66324(5) 0.7594(2) 0.4577(2) 0.6595(2) 0.7121(2) 0.6645(2) 0.5909(2) 0.8656(2) 0.8352(2) 0.8334(2) 0.7784(2) 0.9227(3) 1.1210(3) 1.1716(2) 1.0300(2) 1.2796(3)
0.31369(2) 0.40658(7) 0.31488(8) 0.28684(9) 0.51954(8) 0.59564(8) 0.52746(9) 0.5847(1) 0.6326(1) 0.22660(9) 0.1928(1) 0.1311(1) 0.1023(1) 0.1360(1) 0.1977(1) 0.0379(1)
0.0180(2) 0.0333(5) 0.0305(5) 0.0184(5) 0.0218(5) 0.0230(5) 0.0197(5) 0.0352(7) 0.0361(7) 0.0205(6) 0.0235(6) 0.0289(7) 0.0378(8) 0.0419(8) 0.0293(7) 0.060(1)
0.0262(2) 0.0373(5) 0.0244(5) 0.0486(6) 0.0228(5) 0.0242(5) 0.0198(5) 0.0224(6) 0.0243(6) 0.0257(6) 0.0308(7) 0.0438(8) 0.0398(8) 0.0294(7) 0.0297(7) 0.054(1)
0.0290(2) 0.0282(5) 0.0408(6) 0.0500(7) 0.0259(5) 0.0265(5) 0.0227(6) 0.0307(7) 0.0283(7) 0.0237(6) 0.0313(7) 0.0319(7) 0.0254(7) 0.0318(7) 0.0308(7) 0.042(1)
Acknowledgments. The authors thank Mr Nick Christian for helpful discussions.
References 1. Strechan, A. A.; Paulechka, Y. U.; Kabo, A. G.; Blokhin, A. V.; Kabo, G. J.: 1-Butyl-3-methylimidazolium Tosylate Ionic Liquid: Heat Capacity, Thermal Stability, and Phase Equilibrium of Its Binary Mixtures with Water and Caprolactam. J. Chem. Eng. Data. 52 (2007) 1791–1799. 2. Ogunlaja, A. S.; Hosten, E.; Tshentu, Z. R.: Dispersion of asphaltenes in petroleum with ionic liquids-evaluation of molecular interactions in the binary mixture. Ind. Eng. Chem. Res. 53 (2014) 18390–18401. 3. Leclercq, L.; Suisse, I.; Nowogrocki, G.; Agbossou-Nidercorn, F.: Halide-free highly-pure imidazolium triflate ionic liquids: Preparation and use in palladium-catalysed allylic alkylation. Green Chem. (2007) 1097–1103. 4. Choudhury, A. R.; Winterton, N.; Steiner, A.; Cooper, A. I.; Johnson, K. A.: In situ Crystallization of Low-Melting Ionic Liquids. J. Am. Chem. Soc. 127 (2005) 16792–16793. 5. Blue, E. D.; Gunnoe, T. B.; Petersen, J. L.; Boyle, P. D.: Protonation of Nheterocyclic carbene ligand coordinated to copper(I): Coordination mode of imidazolium cation as a function of counterion as determined by solidstate structures. J. Organomet. Chem. 691 (2006) 5988–5993.
U12 )0.0053(1) )0.0126(4) )0.0057(4) )0.0043(4) )0.0051(4) )0.0020(4) )0.0024(4) )0.0057(5) 0.0004(5) )0.0020(4) )0.0038(5) )0.0001(6) 0.0058(6) )0.0051(6) )0.0070(5) 0.0091(9)
)0.0032(1) )0.0049(4) )0.0047(4) )0.0029(4) )0.0058(4) )0.0032(4) )0.0055(4) )0.0120(5) )0.0076(5) )0.0014(4) )0.0044(5) )0.0100(6) )0.0058(6) )0.0051(6) )0.0054(5) )0.0196(8)
0.0006(1) )0.0034(4) )0.0018(4) 0.0116(5) )0.0015(4) )0.0033(4) 0.0000(4) )0.0035(5) )0.0066(5) )0.0041(5) )0.0059(5) )0.0069(6) )0.0032(6) 0.0015(5) )0.0017(5) 0.0050(8)
6. Allen, F. H.: The Cambridge Structural Database: a quarter of a million crystal structures and rising. Acta Crystallogr. B58 (2002) 380–388. 7. Bondi, A.: van der Waals Volumes and Radii. J. Phys. Chem. 68 (1964) 441–451. 8. Bernstein, J.; Davis, R. E.; Shimoni, L.; Chang, N.-L.: Patterns in Hydrogen Bonding: Functionality and Graph Set Analysis in Crystals. Angew. Chem. Int. Ed. Engl. 34 (1995) 1555–1573. 9. Etter, M. C.; MacDonald, J. C.; Bernstein, J.: Graph-set analysis of hydrogen-bond patterns in organic crystals. Acta Crystallogr. B46 (1990) 256–262. 10. Sheldrick, G. M.: A short history of SHELX. Acta Crystallogr. A64 (2008) 112–122. 11. Farrugia, L. J.: WinGX and ORTEP for Windows: an update. J. Appl. Crystallogr. 45 (2012) 849–854. 12. Macrae, C. F.; Bruno, I. J.; Chisholm, J. A.; Edgington, P. R.; McCabe, P.; Pidcock, E.; Rodriguez-Monge, L.; Taylor, R.; van de Streek, J.; Wood, P.A.: Mercury CSD 2.0 - new features for the visualization and investigation of crystal structures. J. Appl. Crystallogr. 41 (2008) 466–470. 13. Spek, A. L.: Structure validation in chemical crystallography. Acta Crystallogr. D65 (2009) 148–155.
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