Journal of Structural Chemistry. Vol. 55, No. 4, pp. 682-690, 2014. Original Russian Text © 2014 A. N. Makhinya, M. A. Il’in, I. A. Baidina, P. E. Plyusnin, M. R. Gallyamov.
STRUCTURE AND PROPERTIES OF TRIPYRIDINE NITROSOCOMPLEXES OF RUTHENIUM: mer-[Ru(NO)Py3Cl(OH)]Cl⋅1.5H2O AND mer-[Ru(NO)Py3Cl(H2O)]Cl2⋅2H2O⋅0.5HCl A. N. Makhinya,1,2 M. A. Il’in,1,2 I. A. Baidina,1 P. E. Plyusnin,1,2 and M. R. Gallyamov1
UDC 542.06:546.96:548.736
The reaction of K2[Ru(NO)Cl5] with pyridine in aqueous ethanol at pH ∼ 7-8 affords a nitrosoruthenium hydroxocomplex mer-[Ru(NO)Py3Cl(OH)]Cl⋅1.5H2O (I) (yield ∼55%). Treatment of hydroxocomplex I with hydrochloric acid at room temperature gives the aqua complex mer-[Ru(NO)Py3Cl(H2O)]Cl2⋅ 2H2O⋅0.5HCl (II). The structures of the compounds are determined by X-ray crystallography: I, space group P21/n, a = 9.2292(4) Å, b = 11.7781(4) Å, c = 17.4915(7) Å, β = 90.9560(10)°, R = 4.84%; II, space group P-1, a = 7.3528(9) Å, b = 11.5793(11) Å, c = 13.6961(16) Å, α = 84.558(3)°, β = 87.668(4)°, γ = 74.146(4)°, R = 6.22%. Compounds I and II are characterized by powder XRD, 1Н and 13С NMR, and IR spectroscopy. The thermal decomposition of compound II in the inert atmosphere is examined by thermal analysis. DOI: 10.1134/S0022476614040131 Keywords: nitrosocomplexes, ruthenium, amine complexes, pyridine, X-ray crystallography, IR spectroscopy, NMR, thermal analysis.
INTRODUCTION Laser-induced isomerization of nitrosocomplexes makes these compounds promising as the precursors of photoactive multifunctional materials [1-3]. Among ruthenium nitrosocomplexes the compound with four pyridine molecules [Ru(NO)(Py)4Cl](PF6)2⋅0.5H2O exhibits one of the highest known populations of the metastable state [4, 5]. Other complexes of the nitrosopyridine series lack photochemical examination, which is probably related to lacunas in the available information about their synthesis and properties. The purpose of this work is the preparation of novel tripyridine nitrosocomplexes of ruthenium and their structural and physicochemical investigation.
EXPERIMENTAL Starting K2[Ru(NO)Cl5] was obtained with an yield of ∼97% from commercially available ruthenium trichloride hydrate as described in the literature [6]. Other reagents and solvents were used as purchased and were chemically pure or better.
1
Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia. Novosibirsk State University, Russia;
[email protected]. Translated from Zhurnal Strukturnoi Khimii, Vol. 55, No. 4, pp. 716724, July-August, 2014. Original article submitted July 3, 2013.
2
682
0022-4766/14/5504-0682 © 2014 by Pleiades Publishing, Ltd.
TABLE 1. Crystal Data and Selected Refinement Details Compound Temperature, K Unit cell parameters: a, b, c, Å; α, β, γ, deg Space group; Z V, Å3 ρx, g/cm3 μ, mm–1 F(000) θinterval, deg h, k, l range Measured/independent reflections [R(int)] θrange, deg Data completeness, % Refinement Number of parameters S on F 2 R1/wR2 [I > 2σ(I )] R1/wR2 (all data)
I 150(2) 9.2292(4), 11.7781(4), 17.4915(7); 90.9560(10) P21/n; 4 1901.10 1.689 1,130 972 2.33 – 27.49
II 150(2) 7.3528(9), 11.5793(11), 13.6961(16); 84.558(3), 87.668(4), 74.146(4) P-1; 2 1116.54 1.614 1,147 541 2.26 – 27.62
–11 ≤ h ≤ 11, –8 ≤ k ≤ 15, –22 ≤ l ≤ 22 –9 ≤ h ≤ 9, –15 ≤ k ≤ 14, –17 ≤ l ≤ 17 10268/4342 8575/5118 0.0290 0.0475 25.00 25.00 99.6 99.5 Full-matrix least squares technique on F 2 258 271 1.233 1.057 0.0474/0.1097 0.0622/0.1455 0.0531/0.1117 0.0857/0.1548
IR spectra of the samples were measured in KBr pellets on an Scimitar FTS 2000 IR Fourier spectrometer within the wavenumber range 4000-375 cm–1. Powder X-ray diffraction examination of ground crystals was carried out on a DRON-3M diffractometer (R = 192 mm, CuKα radiation, Ni filter, scintillation detector with amplitude discrimination). Thin layers of the samples were applied to the polished side of the standard quartz sample holder. NMR spectra were recorded on a Bruker Avance 500 spectrometer, w.f. 500.000 MHz (1H) and 125.721 MHz 13 ( C); magnetic field strength 11.744 T. The samples were dissolved in dimethylsulfoxide (DMSO); hexamethyldisiloxane (HMDS) was used as the external standard, δ(1H) = 0.60 ppm, δ(13C) = 36.500 ppm. Unit cell parameters and intensity data were measured on an automated four-circle X8 APEX Bruker diffractometer (MoKα radiation, graphite monochromator, CCD area detector). The structures were solved by the heavy atom method and refined in the anisotropic approximation; hydrogen atoms were put in idealized positions and refined isotropically. All calculations were performed using SHELX-97 [7]. Crystal data and selected refinement details are given in Table 1. Positional and isotropic displacement parameters 2 (Å ) for I and II are listed in Table 2. CIF files of the structures have been deposited with the Cambridge structural database (CCDC Nos. 841641 and 945508) and are available free of charge at www.ccdc.cam.ac.uk/data_request/cif. Thermogravimetric analysis was carried out on a TG 209 F1 Iris® thermo microbalance (NETZSCH) at a heating rate of 10 deg/min in a helium stream of 30 ml/min; Al2O3 crucible; load ∼7 mg. Experimental results were processed using OriginPro 7.5 [8]. Synthesis of mer-[Ru(NO)Py3Cl(OH)]Cl⋅1.5H2O (I). 0.4 g (1.0⋅10–3 mol) of ground K2[Ru(NO)Cl5], 15 ml of aqueous ethanol (∼50% V/V), ∼0.25 ml of Py (3.1⋅10–3 mol), and ∼0.12 g of KHCO3 (1.2⋅10–3 mol) were combined in a beaker. The beaker was covered with a clock glass and the mixture was heated (65-70°C) under continuous stirring for ∼10 min. Then the mixture was fast brought to boiling and then cooled in an ice bath. After repeating this procedure the reaction mixture was concentrated to 1/2 of the starting volume (∼65°C, ∼30 min). The resulting light-orange precipitate of trans-[Ru(NO)Py2Cl2(OH)] (∼20%) was collected on a frit, washed with ∼5 ml of water, ethanol, and acetone. 683
TABLE 2. Positional and Isotropic Displacement Parameters of Atoms (Å2) for I and II Atom 1
Ru(1) Cl(1) N(1) O(1) O(2) N(11) N(21) N(31) C(11) C(12) C(13) C(14) C(15) C(21) C(22) C(23) C(24) C(25) C(31) C(32) C(33) C(34) C(35) O(1W) O(2W) Cl(2) Cl(3) Ru(1) Cl(1) O(1) O(2) N(1) N(11) N(21) N(31) C(11) C(12) C(13) C(14) C(15) C(21) C(22)
684
x 2
y 3
z 4
Ueq 5
0.61261(4) 0.51388(12) 0.5984(4) 0.5835(4) 0.6245(4) 0.8225(4) 0.4061(4) 0.6988(4) 0.9217(5) 1.0634(5) 1.1037(6) 1.0023(6) 0.8628(5) 0.3232(5) 0.1918(6) 0.1422(6) 0.2259(6) 0.3575(6) 0.6998(6) 0.7526(6) 0.8083(6) 0.8061(5) 0.7491(5) 0.2550(6) 0.6527(12) 0.5668(3) 0.5000
I 0.72336(3) 0.65710(10) 0.5830(3) 0.4873(3) 0.8725(3) 0.6928(3) 0.7693(3) 0.7980(3) 0.6362(4) 0.6211(4) 0.6647(5) 0.7211(5) 0.7338(4) 0.8399(4) 0.8793(5) 0.8440(5) 0.7681(5) 0.7343(4) 0.9118(4) 0.9652(4) 0.9014(4) 0.7840(4) 0.7354(4) 0.9600(4) 0.9425(8) 0.9618(2) 0.5000
0.225046(19) 0.34065(6) 0.1911(2) 0.1821(2) 0.26950(18) 0.2695(2) 0.1828(2) 0.1258(2) 0.2286(3) 0.2542(3) 0.3241(3) 0.3674(3) 0.3384(3) 0.2230(3) 0.1946(3) 0.1241(3) 0.0831(3) 0.1136(3) 0.1195(3) 0.0555(3) –0.0035(3) 0.0030(3) 0.0675(2) 0.3833(3) 0.4265(5) 0.44727(14) 0.0000
0.01215(12) 0.0204(2) 0.0159(8) 0.0317(9) 0.0164(7) 0.0144(7) 0.0165(7) 0.0141(7) 0.0181(9) 0.0222(10) 0.0276(11) 0.0259(11) 0.0197(9) 0.0221(10) 0.0278(11) 0.0311(12) 0.0311(12) 0.0231(10) 0.0225(10) 0.0270(11) 0.0220(10) 0.0212(10) 0.0173(9) 0.0489(13) 0.0343(19) 0.0255(5) 0.0906(14)
0.06018(7) 0.1643(2) –0.2916(7) 0.3112(6) –0.1547(7) –0.0340(7) 0.1826(7) –0.0160(7) –0.1235(9) –0.1844(9) –0.1543(10) –0.0629(9) –0.0041(9) 0.3420(9) 0.4176(10)
II 0.16412(4) 0.15449(14) 0.1154(4) 0.1897(4) 0.1390(4) 0.3519(4) –0.0222(4) 0.1802(4) 0.4041(6) 0.5279(6) 0.6002(6) 0.5467(6) 0.4225(5) –0.0764(5) –0.2001(6)
0.83420(4) 0.99665(11) 0.8979(3) 0.7848(3) 0.8730(4) 0.8349(4) 0.8319(4) 0.6875(4) 0.9141(5) 0.9149(5) 0.8330(5) 0.7534(5) 0.7557(4) 0.8818(5) 0.8909(5)
0.01177(14) 0.0205(3) 0.0234(10) 0.0185(9) 0.0159(10) 0.0148(10) 0.0141(10) 0.0143(10) 0.0195(13) 0.0211(13) 0.0247(15) 0.0215(14) 0.0164(12) 0.0179(13) 0.0247(14)
TABLE 2. (Continued) 1
2
3
4
5
C(23) C(24) C(25) C(31) C(32) C(33) C(34) C(35) Cl(2) Cl(4) Cl(3) O(1W) O(3W) O(2W)
0.3269(11) 0.1670(10) 0.0955(9) 0.1009(9) 0.0523(11) –0.1205(12) –0.2469(12) –0.1885(9) 0.4530(2) 0.6128(3) 0.2014(5) 0.3793(9) 0.5449(15) 0.4054(19)
–0.2705(6) –0.2159(6) –0.0925(5) 0.1252(6) 0.1386(7) 0.2092(8) 0.2671(7) 0.2494(6) 0.38268(14) 0.00604(17) 0.4197(3) 0.5460(5) 0.1167(9) 0.3136(17)
0.8446(5) 0.7918(5) 0.7882(4) 0.6175(5) 0.5203(5) 0.4936(5) 0.5639(5) 0.6604(5) 0.84897(12) 0.68925(14) 0.5229(3) 0.6538(4) 0.4555(8) 0.3963(10)
0.0260(15) 0.0244(14) 0.0172(12) 0.0188(13) 0.0279(16) 0.039(2) 0.0362(19) 0.0207(13) 0.0225(3) 0.0323(4) 0.0309(8) 0.0406(14) 0.032(2) 0.101(8)
The obtained red-orange mother liquor was concentrated at room temperature to a small volume (∼0.5 ml), diluted with ∼20 ml of ethanol, and precipitated KCl was separated. The remaining solution was again concentrated at room temperature to a small volume and added with ∼0.5 ml of ethanol, ∼10 ml of acetone, and ∼0.5 ml of diethyl ether. Vigorous stirring of the resultant mixture with a glass stick for 5-10 min afforded the bright-yellow precipitate of I. The product obtained (∼0.3 g) was collected on a frit, washed with ∼2 ml of acetone, and dried in air. Yield ∼55%. Crystals of X-ray quality were obtained by slow evaporation of a solution of I in DMF. The compound is well-soluble in water, ethanol, DMF, DMSO, sparingly soluble in acetone, and insoluble in diethyl ether. IR spectrum (ν, cm–1): 3440-3400 ν(OH), 3100-3000 ν(CH), 1853 ν(NO), 1643 δ(HOH), 1604, 1570, 1486, 1449, 1358 ν(Car–Car), ν(Car–Nar), 1216, 1157, 1068, 1016 δ(CHin-plane), 912 δ(RuOH), 767, 697 δ(CHout-of-plane), 614 ν(Ru–NNO), δ(Ru–NO), 560 ν(Ru–O), 461 ν(Ru–NPy). NMR 1H (δ, ppm): 9.12 d (2H, H2,6), 9.05 d (4H, H2,6), 8.56 m (3H, H4), 8.05 m (6H, H3,5). NMR 13C (δ, ppm): 148.72, 147.64 (C2,6), 137.54, 137.04 (C4), 123.25, 122.47 (C3,5). Synthesis of mer-[Ru(NO)Py3Cl(H2O)]Cl2⋅2H2O⋅0.5HCl (II). ∼50 mg of I was dissolved in в ∼1.5 ml of water and ∼1.5 ml of concentrated HCl was added, the yellow color of the solution turning into red-orange. The resultant solution was evaporated to dryness at room temperature (quantitative yield). Crystals of II suitable for X-ray diffractometry were obtained by slow evaporation of the reaction solution. The compound is well soluble in hydrochloric acid (> 6 M), ethanol, DMF, DMSO. IR spectrum (ν, cm–1): 3350-3200 ν(OH), 3100-3000 ν(CH), 2658, 2417 ν(H3O+), 1926 ν(NO), 1700-1640 δ(HOH), 1611, 1491, 1453, 1366 ν(Car–Car), ν(Car–Nar), 1223, 1163, 1069, 1018 δ(CHin-plane), 955 δ(RuOH2), 761, 694, 652 δ(CHout-of-plane), 611 ν(Ru–NNO), δ(Ru–NO), 579 ν(Ru–O), 448 ν(Ru–NPy). NMR 1H (δ, ppm): 9.07 d (2H, H2,6), 9.02 d (4H, H2,6), 8.53 m (3H, H4), 8.05 m (6H, H3,5). NMR 13C (δ, ppm): 148.62, 147.53 (C2,6), 137.59, 137.07 (C4), 123.28, 122.47 (C3,5).
RESULTS AND DISCUSSION On heating in aqueous ethanol the [Ru(NO)Cl5]2– anion is aquated [9, 10] [Ru(NO)Cl5]2– + H2O [Ru(NO)Cl4(H2O)]– + Cl–.
(1) 685
Fig. 1. Structures of mer-[Ru(NO)(Py)3Cl(OH)]+ (a) and mer-[Ru(NO)Py3Cl(H2O)]2+ (b) complex ions. The [Ru(NO)Cl4(H2O)]– aqua complex behaves as a weak acid (Ka ∼ 10–6) [9] [Ru(NO)Cl4(H2O)]– [Ru(NO)Cl4(OH)]2– + H+.
(2)
To neutralize Н+ potassium hydrocarbonate was added to the reaction mixture. The overall equation for the formation of hydroxocomplex I can be written as follows: [Ru(NO)Cl5]2– + 3Py + HCO3− → [Ru(NO)Py3Cl(OH)]+ + 4Cl– + CO2↑. In the synthesis of I poorly soluble trans-[Ru(NO)Py2Cl2(OH)] is formed, as identified by IR spectroscopy and powder X-ray diffraction [11]. It is noteworthy that the mother liquor should be concentrated at the room temperature because heating favors the formation of the dipyridine complex and diminishes the yield of the target product. The reaction of hydroxotripyridine complex I with hydrochloric acid affords the mer-[Ru(NO)Py3Cl(H2O)]2+aqua complex that can be isolated as compound II after concentration. To avoid the degradation of II, the solution was concentrated at the room temperature. Description of the crystal structures. Crystal structures of I and II are built from complex mer[Ru(NO)(Py)3Cl(OH)]+ or mer-[Ru(NO)Py3Cl(H2O)]2+ cations, Cl− anions, and crystallization water molecules. Compound II additionally contains H3O+ hydroxonium cations as dictated by the charge balance. The structures of the complex cations in the thermal ellipsoid representation with atom labeling are illustrated in Fig. 1. Selected bond lengths and angles are listed in Table 3. In the complex cations of I and II the central Ru atom has a slightly distorted octahedral environment. The equatorial plane is formed by three nitrogen atoms of the pyridine molecules and the chlorine atom, while the axial positions are occupied by the nitrogen atom of the nitroso group and the oxygen atom. The O(1)–N(1)–Ru(1) fragment in the structures of I and II is almost linear (176° and 168° respectively), which is characteristic of the majority of ruthenium nitrosocomplexes [12-14]. Bond angles at the Ru(1) atom deviate from 90° by ±8.1° (for I) and ±5.1° (for II). In both structures the ruthenium atom is shifted from the equatorial plane towards the nitroso group by ∼0.1 Å. Hydroxocomplex I has an eclipsed conformation of the pyridine ligands; the tilt of both pyridine molecules to the N(1)–Ru(1)–O(2) line is ∼40°. Aqua complex II has a staggered conformation of the pyridine ligands; the angles made by the planes of the pyridine rings to the N(1)–Ru(1)–O(2) line is ∼45°. The nitroso groups in the complexes have usual geometric characteristics and are in agreement with the literature data [12, 13, 15, 16]: the average Ru(1)–N(1) bond length is 1.75 Å, the N(1)–O(1) distance is 1.145 Å in both structures.
686
TABLE 3. Selected Bond Lengths (Å) and Angles (deg) in the Structures of I and II I
II Bond lengths
Ru(1)–N(1) Ru(1)–O(2) Ru(1)–N(21) Ru(1)–N(11) Ru(1)–N(31) Ru(1)–Cl(1) N(1)–O(1)
1.761(4) 1.923(3) 2.103(4) 2.106(4) 2.113(4) 2.3643(11) 1.146(5)
N(1)–Ru(1)–O(2) N(1)–Ru(1)–N(21) O(2)–Ru(1)–N(21) N(1)–Ru(1)–N(11) O(2)–Ru(1)–N(11) N(21)–Ru(1)–N(11) N(1)–Ru(1)–N(31) O(2)–Ru(1)–N(31) N(21)–Ru(1)–N(31) N(11)–Ru(1)–N(31) N(1)–Ru(1)–Cl(1) O(2)–Ru(1)–Cl(1) N(21)–Ru(1)–Cl(1) N(11)–Ru(1)–Cl(1) N(31)–Ru(1)–Cl(1) O(1)–N(1)–Ru(1)
175.75(16) 93.52(16) 87.25(15) 91.56(16) 87.75(14) 174.86(15) 98.09(16) 86.12(14) 87.46(14) 91.04(14) 87.18(13) 88.62(10) 91.45(11) 89.59(10) 174.67(11) 168.0(4)
Ru(1)–N(1) Ru(1)–O(2) Ru(1)–N(31) Ru(1)–N(11) Ru(1)–N(21) Ru(1)–Cl(1) O(1)–N(1) O(2)–H(1) O(2)–H(2)
1.737(5) 2.028(4) 2.086(5) 2.094(5) 2.102(5) 2.3651(15) 1.144(7) 0.88(2) 0.882(19)
N(1)–Ru(1)–O(2) N(1)–Ru(1)–N(31) O(2)–Ru(1)–N(31) N(1)–Ru(1)–N(11) O(2)–Ru(1)–N(11) N(31)–Ru(1)–N(11) N(1)–Ru(1)–N(21) O(2)–Ru(1)–N(21) N(31)–Ru(1)–N(21) N(11)–Ru(1)–N(21) N(1)–Ru(1)–Cl(1) O(2)–Ru(1)–Cl(1) N(31)–Ru(1)–Cl(1) N(11)–Ru(1)–Cl(1) N(21)–Ru(1)–Cl(1) Ru(1)–O(2)–H(1) Ru(1)–O(2)–H(2) H(1)–O(2)–H(2) O(1)–N(1)–Ru(1)
177.9(2) 91.4(2) 86.93(19) 95.1(2) 86.23(19) 89.4(2) 90.6(2) 88.14(18) 91.68(19) 174.2(2) 92.83(17) 88.86(13) 175.44(14) 88.59(14) 89.92(14) 126(4) 126(4) 104(3) 176.0(5)
Bond angles
In the structures of both compounds the Ru–N(Py) distances fall within 2.086-2.113 Å (the average values are ∼2.107 Å for I and ~2.094 Å for II) in agreement with the data of [12, 17]. The lengths of the Ru(1)–Cl(1) bond are the same in the structures of I and II and are ∼2.36 Å, which is close to similar values for the known amine complexes of ruthenium containing the chloride ion in the equatorial plane [12, 13]. The structures of I and II are layered (Fig. 2); the interlayer voids are occupied by chloride ions, water molecules, + and H3O cations (for II). The shortest distances between the ruthenium atoms are 6.7 Å and 7.4 Å for I and II. One pyridine ring out of the three participates in the π-stacking within the layers of the structure of I (the interplane distance between the pyridine rings is ∼3.4 Å). Additionally, there are T-stacking interactions with the contact between the pyridine hydrogen atom and the plane of the neighboring pyridine ring of ∼3.0 Å. The structural units are joined by O–H⋯O hydrogen bonds involving water molecules (∼3.7 Å) and both water molecules and coordinated hydroxide ions (∼2.9 Å). Non-coordinated chloride ions also form hydrogen bonds to water molecules and coordinated hydroxide ions at the distances Cl⋯О ∼3.2 Å.
687
Fig. 2. Packing of ions and the hydrogen bonding in the crystals of I (a) and II (b). In the structure of II one water molecule is split over two positions. The crystals exhibit the extended hydrogen bonding involving coordinated Cl atoms, non-coordinated chloride anions, and crystallization water molecules. These contacts vary within 2.3-3.3 Å. NMR spectroscopy. 1H NMR spectra of complexes I and II exhibit three groups of signals belonging to three types of protons in the coordinated pyridine molecules. Chemical shifts of the pyridine signals are strongly influenced by the transsubstituent as well as the solvent. For ruthenium nitrosocomplexes the values range within 7-10 ppm [12, 18, 19]. The first low-field signal (8.5-10 ppm) is attributed to the ortho-proton of the pyridine molecule; this signal is split into a doublet by the interaction with the neighboring proton. The second signal at the higher field is a triplet of the paraproton having two neighboring protons. The third signal of the meta-proton (7-8 ppm) is also a triplet. The integrated intensities correspond to the ratio of the ortho-, para- and meta-protons in the pyridine molecule as 2:1:2. In 13C NMR spectra of complexes I and II there are also three groups of signals in a similar sequence corresponding to the ortho-, para-, and meta-carbon atoms (160-120 ppm). IR spectroscopy. IR spectra of the obtained compounds exhibit very strong vibrations ν(NO) at 1853 cm–1 (for I) and 1926 cm–1 (for II). These bands fall within the range characteristic of the majority of ruthenium nitrosocomplexes containing diamagnetic Ru(II) and the linearly coordinated NO+ ligand [19-22]. The IR spectra of both compounds have bands typical of coordinated pyridine molecules [11, 23]: narrow bands of low and medium intensity ν(CH) (3100-3000 cm–1), narrow bands of medium and high intensity ν(Car–Car) and ν(Car–Nar) (1611-1358 cm–1), as well as medium and strong bands δ(CHin-plane) and δ(CHout-of-plane) in the regions of 1223-1016 cm–1 and 767-652 cm–1 respectively. Additionally, the spectra contain the bands originating from the molecules of crystallization and coordinated water (for II), and the coordinated hydroxide ion in I. It is noteworthy that for the aqua complex these bands are broader, which can be related to the more extensive hydrogen bonding in compound II. The presence of the hydroxonium cation in the structure of II, concluded from the X-ray data, is also manifested in the IR spectrum as broad bands ν(H3O+) near 2660 cm–1 and 2420 cm–1 [24]. TGA studies. Fig. 3 illustrates the thermal decomposition curves of compound II in the helium atmosphere. Hydrogen chloride is gradually lost at room temperature, and, thus, the curves lack the effects corresponding to its removal. Compound II loses crystallization and coordinated water at the first step within the temperature range ∼30-100°C. The heating of II at ∼120-170°C results in the loss of one pyridine molecule and affords (according to the IR data) mer-[Ru(NO)Py2Cl3]. Further decomposition of compound II (above 180°С) occurs in several poorly resolved stages that hardly can be attributed to the stoichiometric loss of pyridine. The final product, as indicated by powder X-ray diffraction, contains metallic ruthenium and an amorphous phase that is probably carbon. 688
Fig. 3. Thermal decomposition plots for compound II. To summarize, we have suggested a technique to prepare a nitrosoruthenium tripyridine hydroxocomplex mer[Ru(NO)Py3Cl(OH)]Cl⋅1.5H2O (I). The interaction of this compound with concentrated hydrochloric acid at room temperature quantitatively yields the aqua complex mer-[Ru(NO)Py3Cl(H2O)]Cl2⋅2H2O⋅0.5HCl (II). Both compounds have been characterized by a number of physicochemical techniques, and their structures have been determined by XRD. The crystalline phase of II has been demonstrated to contain hydroxonium cations. When kept in air at room temperature, compound II degrades evolving hydrogen chloride. Its heating to 170°С affords the trichlorodipyridine complex mer[Ru(NO)Py2Cl3]. The final products of the thermal decomposition are ruthenium and amorphous carbon. The authors express their gratitude to N. I. Alferova for recording the IR spectra and A. V. Alekseev for X-ray powder studies. Partial financial support from State contract No. 14.V37.21.0141 (Federal Program “Human Resources for Science, Research, Education and Innovation in Russia” for 2009-2013) is gratefully acknowledged.
REFERENCES 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17.
D. Schaniel, T. Woike, B. Delley, et al., Phys. Chem. Chem. Phys., 7, 1164 (2005). P. Coppens, D. V. Fomitchev, M. D. Carducci, and K. Culp, J. Chem. Soc. Dalton Trans., 39, 865 (1998). L. A. Kusch, S. Golhen, O. Cador, et al., J. Cluster Sci., 17, 303 (2007). D. Schaniel, B. Cormary, I. Malfant, et al., Phys. Chem. Chem. Phys., 9, 3717 (2007). B. Cormary, S. Ladeira, K. Jacob, et al., Inorg. Chem., 51, 7492 (2012). V. A. Emel’yanov, S. P. Kranenko, and A. V. Belyaev, Zh. Neorg. Khim., 46, No. 3, 404 (2001). G. M. Sheldrich, SHELX-97, Release 97-1, Univ. Göettingen, Germany (1997). OriginPro 7,5, SR0 v.7.5714 B(714), OriginLab Corporation-Northampton, USA (2003). E. E. Mercer, W. M. Campbell Jr., and R. M. Wallace, Inorg. Chem., 3, No. 7, 1018 (1964). V. A. Emel’yanov, I. A. Baidina, S. P. Khranenko, et al., J. Struct. Chem., 44, No. 1, 37-45 (2003). A. N. Makhinya, M. A. Il’in, E. V. Kabin, et al., Russ. J. Coord. Chem., 40, No. 5, 297 (2014). B. Serli, E. Zangrando, T. Gianferrara, et al., Coord. Chem. Rev., 245, 73 (2003). V. A. Emel’yanov, I. A. Baidina, M. A. Il’in, and S. A. Gromilov, J. Struct. Chem., 47, No. 2, 380-382 (2006). M. A. Il’in, V. A. Emel’yanov, I. A. Baidina, et al., Zh. Neorg. Khim., 52, No. 1, 67 (2007). H. Nishimura, H. Matsuzawa, T. Togano, et al., J. Chem. Soc. Dalton Trans., 137 (1990). M. A. Il’in, V. A. Emel’yanov, and I. A. Baidina, J. Struct. Chem., 51, No. 1, 99-106 (2010). D. Ooyama, Y. Miura, Y. Kanazawa (Kitanaka), et al., Inorg. Chim. Acta, 237, 47 (1995).
689
18. 19. 20. 21. 22. 23. 24.
690
B. J. Coe, T. J. Meyer, and P. S. White, Inorg. Chem., 34, 593 (1995). F. Bottomley and M. Mukaida, J. Chem. Soc. Dalton Trans., 1933 (1982). E. E. Mercer, W. A. McAlister, and J. R. Durig, Inorg. Chem., 5, No. 11, 1881 (1966). M. A. Il’in, V. A. Emel’yanov, A. V. Belyaev, et al Zh. Neorg. Khim., 53, No. 7, 1152 (2008). M. G. Gomes, C. U. Davanzo, S. C. Silva, et. al., J. Chem. Soc. Dalton Trans., 601 (1998). S. S. S. Borges, C. U. Davanzo, E. E. Castellano, et al., Inorg. Chem., 37, 2670 (1998). A. V. Kostrikin, R. V. Kuznetsova, O. V. Kosenkova, et al., Voprosy Sovremennoi Nauki i Praktiki, Un-t im. V. I. Vernadskogo, 2, No. 8, 181 (2007).
