Phase equilibria in the thiourea-benzene system

Phase equilibria in the thiourea (host)-benzene (guest) binary system with clathrate formation were studied over the temperature range 260–460 K by physicochemical analysis methods. The stoichiometry and conditions of the existence of the 2.40(±0.02)(NH₂)₂CS · C₆H₆ compound, which incongruently decomposed at 358.7 K into rhombic thiourea and the guest component, were determined. The parameters of the Bravaisrhombohedral cell of the clathrate (space group R \(\bar 3\) c) were found to be a = 15.921(6), c = 12.417(8) Å, and V = 2725(5) ų; d _calc = 1.192 g/cm³ and d _expt = 1.195(7) g/cm³. The packing of guest molecules in the rhombohedral host framework was modeled taking into account stoichiometry and unit cell parameters to show that benzene molecule planes were tilted with respect to the c channel axis with the formation of a monomolecular closely packed chain in the guest subsystem.     

Crystal structure of the 1:3 thiourea-hexachloroethane inclusion compound at 295 K

The crystal structure of the 1:3 thiourea-hexachloroethane inclusion compound at 295 K has been determined. The parameters of the rhombohedral Bravais cell (space group R3ˉc) are a = 16.097(2) Å, c = 12.450(3) Å, V = 2793.6(8) ų, d _calc = 1.659 g/cm³, d _exp = 1.661±0.005 g/cm³, Z = 6 for C₅H₁₂Cl₆N₆S₃. The disordered guest molecules lie in the channels (parallel to the c axis) of the clathrate framework constructed from thiourea molecules linked by N-H...S hydrogen bonds. The mutual arrangement of the carbon and chlorine atoms is such that they define four orientations of the C-C bond relative to the channel of the host framework with nearly eclipsed conformations of hexachloroethane: one orientation along the triple bond axis (channel axis) and three equiprobable orientations at an angle of 74(2)° to the axis; for the coaxial orientation, there are two different configurations of the guest with slightly different geometries. The relative contributions of each of the five orientations were determined from the site occupancies of the guest atoms: 26.18 (coaxial orientations) and 3×19%. The resulting structure model is compared with the literature data about guest disordering in the structure of an adduct of the same composition determined at 233 K and with other similar structures. Original Russian Text Copyright ? 2007 by S. F. Solodovnikov, G. N. Chekhova, G. V. Romanenko, N. V. Podberezskaya, Z. A. Solodovnikova, D. V. Pinakov, and A. R. Semenov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 48, No. 2, pp. 348–357, March–April, 2007.     

Crystal structure of Pb<Subscript>2</Subscript>[Fe(CN)<Subscript>6</Subscript>]NO<Superscript>3</Superscript>·5.5H<Subscript>2</Subscript>O

Synthesis of a mixed complex compound Pb₂[Fe(CN)₆]NO₃·5.5H₂O is described. The results of its X-ray structural investigation are presented. Crystal data: C₆H₁₁FeN₇O_8.50Pb₂: a = 7.2582(6) Å, b = 21.838(3) Å, c = 11.612(1) Å; β = 107.91(1)°, V = 1751.4(3) ų, Z = 4, d_calc = 2.986 g/cm³, space group P2₁/m, R = 0.038. The compound has a framework polymer structure.     

Crystal structure of the co-crystal ALA-VAL·ALA·H<Subscript>2</Subscript>O: A layered inclusion compound

A co-crystal of L-alanyl-L-valine (AV) and L-alanine (A), AV·A·(H₂O), has been prepared and characterized by single crystal XRD analysis. Crystal data: C₁₁H₂₅N₃O₆; M = 295.3; orthorhombic, space group P2(1)2(1)2(1); a = 16.4773(17) Å, b = 18.3932(19) Å, c = 5.0398(5) Å, V = 1527.4(3) ų, Z = 4; d _calc = 1.284 g/cm³. Experimental parameters: T = 100 K; diffractometer, radiation: Kappa APEX II, graphite-monochromatized MoK _α ; R ₁ = 0.046, wR ² = 0.120 for 4639 unique reflections and 214 refinement parameters. The L-alanyl-L-valine dipeptide molecules assemble to form a parallel β-sheet through hydrogen bonds, while the L-alanine molecules fill the large channels located in the interlayer space. AV·A·(H₂O) is the first layered structure based on a representative of hydrophobic dipeptides that form hexagonal tubular structures in the solid state, as well as the first inclusion compound of AV with a chiral guest.     

Structure of the 1:1 complex of dimethyl sulfoxide with hydroquinone: Supramolecular architecture based on D-H⋯A hydrogen bonds (D = O,C; A = O, π)

The hydroquinone-dimethyl sulfoxide-toluene system was investigated by thermal and X-ray diffraction analyses. The crystal structure of the 1:1 complex of hydroquinone with dimethyl sulfoxide was determined. Crystal data: C₈H₁₂O₃S, M = 188.24, triclinic system, space group P1¯, unit cell parameters: a = 7.4202(2) Å, b = 8.4046(3) Å, c = 8.7340(3) Å; α = 100.830(1)°, β = 99.794(1)°, γ = 114.129(1)°; V = 469.35(4) ų, Z = 2, d _calc = 1.332 g/cm³, R1 = 0.028, T = 100 K. The molecules are linked in a supramolecular assembly via D-H...A hydrogen bonds (D = O, C; A = O, π).     

Synthesis of spiro[(6-phenyl-3,4-dihydro-2H-1,3-dioxine)-2<Emphasis Type="Italic">R</Emphasis>(<Emphasis Type="Italic">S</Emphasis>), 3′-(19′,28′-oxidooleanan)]-4-ones and X-ray diffraction analysis of their configuration

The structure of two stereoisomeric spiroadducts of allobetulone with 5-phenyl-2,3-dihydrofuran-2,3-dione was established by X-ray diffraction (XRD) analysis. The crystals of the 2R isomer are orthorhombic, P2₁2₁2₁, a = 10.825(5) Å, b = 12.849(6) Å, c = 23.358(9) Å; V = 3249(2) ų, Z = 4, d _calc = 1.200 g/cm³; the crystals of the 2S isomer hemihydrate are triclinic, P1, a = 11.505(7) Å, b = 12.192(8) Å, c = 13.123(8) Å; α = 103.35(5)°, β = 100.80(5)°, γ = 90.98(5)°; V = 1756(2) ų, Z = 2, d _calc = 1.127 g/cm³. The molecular structure of the spiroadducts is discussed.     

Investigation of pentaamminechloroplatinum(IV) perrhenate dihydrate

The crystal structure of the [Pt(NH₃)₅Cl](ReO₄)₃·2H₂O salt is determined. Crystallographic data: a = 10.3476(2) Å, b = 12.8955(2) Å, c = 14.3536(3) Å, β = 105.241(10)°, V = 1847.94(6) ų, space group P ₂1/n, Z = 4, d _x = 3.962 g/cm³. Thermal decomposition of the compound is studied in a helium and hydrogen atmosphere. A two-phase product arises in the former case, in the latter a substitution Re_0.75Pt_0.25 solid solution with unit cell parameters: a = 2.767(2) Å, c = 4.441(3) Å, space group P6₃/mmc.     

Crystal structures of <Emphasis Type="Italic">trans</Emphasis>-[Re<Subscript>6</Subscript>S<Subscript>8</Subscript>(CN)<Subscript>2</Subscript>L<Subscript>4</Subscript>] complexes,L = pyridine or 4-methylpyridine

The structures of three novel octahedral rhenium cluster compounds [Re₆S₈(CN)₂(py)₄]·H₂O (1), [Re₆S₈(CN)₂(4-Mepy)₄] (2), [Re₆S₈(CN)₂(4-Mepy)₄]·4-Mepy (3) (py = pyridine, 4-Mepy = 4-methylpyridine) are determined by X-ray crystallography. Crystal data are: C2/m space group, a = 14.813(1) Å, b = 14.772(1) Å, c = 9.2122(6) Å, β = 119.085(2)°, V = 1761.7(2) ų, d _x = 3.318 g/cm³, R = 0.0585 (1); I4₁/amd space group, a = 16.0018(3) Å, c = 14.7186(5) Å, V = 3768.81(16) ų, d _x = 3.169 g/cm³, R = 0.0489 (2); P2₁/c space group, a = 9.0452(4) Å, b = 15.8065(7) Å, c = 15.2951(6) Å, β = 103.700(2)°, V = 2124.57(16) ų, d _x = 2.957 g/cm³, R = 0.0245 (3). Molecular cluster complexes interact via π-π stacking affording 3D frameworks in 1 and 2 and chains in 3.     

Synthesis and study of ammonium decamolybdodimetallates

Ammonium decamolybdodimetallates (NH₄)_n[M₂Mo₁₀O₃₄(OH)₄] · 7H₂O, where M = Cr³⁺ (n = 6), Cu²⁺ (n = 8), or Ni²⁺ (n = 8), were synthesized for the first time and studied by X-ray diffraction, thermogravimetry, and IR spectroscopy. The compounds crystallize in the triclinic system with the following unit cell parameters: a = 10.68(2) Å, b = 9.46(2) Å, c = 7.97(2) Å, α = 75.12(3)°, β = 96.82(3)°, γ = 102.21(3)°, V = 754.4(3) ų, ρ_calcd = 4.05 g/cm³, Z = 1 for the chromium compound; and a = 10.57(2) Å, b = 9.29(2) Å, c = 8.47(2) Å, α = 73.91(3)°, β = 96.05(3)°, γ = 104.71(3)°, V = 854.3(3) ų, ρ_calcd = 3.68 g/cm³, Z = 1 (for the copper compound); and a = 10.96(2) Å, b = 8.95(2) Å, c = 7.40(2) Å, α = 71.76(3)°, β = 97.04(3)°, γ = 102.91(3)°, V = 875.3(3)ų, ρ_calcd = 3.65 g/cm₃, Z = 1 for the nickel compound.     

Supramolecular architecture of the 1:1 complex of phloroglucinol with dimethyl sulfoxide

The phase diagram of the phloroglucinol (1,3,5-trioxybenzol)-dimethyl sulfoxide system is studied. The system is found to form a 1:1 molecular complex of phloroglucinol with dimethyl sulfoxide. The crystal structure of the complex is determined. The crystallographic data for C₈H₁₂O₄S, M = 204.24, monoclinic system, P2₁/n space group, unit cell parameters: a = 9.0345(2)Å, b = 9.6895(3)Å, c = 10.9960(3)Å, β = 98.865(1)°, V = 951.09(4) ų, Z = 4, d _x = 1.426 g/cm³, R1 = 0.0283, T = 150 K. The molecules are joined in a supramolecular ensemble via O-H...O hydrogen bonds.     

Electronic and crystal structure of (N-CH<Subscript>3</Subscript>-2,2′-bipyridinium)(dodecahydro-dicarba-<Emphasis Type="Italic">nido</Emphasis>-undecaborate)

The compound [N-Me-2,2′-Bipy]⁺[C₂B₉H₁₂]^?-(N-CH₃-2,2′-bipyridinium)(dodecahydro-dicarba-nidoundecaborate) has been synthesized, and its structure has been determined. The compound was defined by IR, ¹¹B and ¹⁴N NMR, and X-ray photoelectron spectroscopy. Crystal data: C₁₃H₂₃B₉N₂, M = 304.62, monoclinic crystals, space group P2₁/c, a = 11.840(4) Å, b = 10.051(3) Å, c = 15.573(6) Å, β = 102.43(3)°, V = 1809.8(10) ų, Z = 4, d _calc = 1.118 g/cm³, R = 0.0607.     

Structure and properties of the volatile isomers of bis(1,1,1-trifluoro-5,5-dimethylhexane-2,4-dionato) of platinum(II)

In the work, isomeric complexes of platinum(II) with the (ptac)^–1 pivaloyltrifluoroacetonate ion (Pt((CH₃)₃–CO–CH–CO–CF₃)₂) are studied. The synthesis and chromatographic separation of Pt(ptac)₂ isomers are described, TGA data for the separated isomers are given, and the crystal structures of the solid phases are studied. The cis-Pt(ptac)₂ complex crystallizes in the space group P-1, a = 10.7091(4) Å, b = 12.7787(6) Å, c = 16.0154(8) Å, α = 92.389(2)°, β = 90.868(2)°, γ = 112.1260(10)°, V = 2027.39(16) ų, Z = 4, d _calc = 1.918 g/cm³. The trans-Pt(ptac)₂ complex crystallizes in the space group C2/m, a = 13.3235(5) Å, b = 8.5515(3) Å, c = 9.6694(3) Å, β = 118.5880(10)°, V = 967.38(6) Å3, Z = 2, d _calc = 2.010 g/cm3. The structures of the complexes are molecular, the Pt atom has a square coordination of four oxygen atoms of two ligands; for cis-Pt(ptac)2, the Pt–Oav distance is 1.968 Å, for trans-Pt(ptac)2 it is 1.980 Å.     

Crystallochemical study of ruthenium(III) tris-dipivaloylmethanate

The structure of ruthenium(III) dipivaloylmethanate is determined by single crystal X-ray diffraction at temperature of 150 K. The crystallographic data for C₃₃H₅₇O₆Ru are as follows: a = 9.6119(11) Å, b = 17.4603(19) Å, c = 21.519(2) Å, β = 95.187(2)°, C2/c space group, V = 3596.7(7) ų, Z = 4, d_calc = = 1.202 g/cm³, R = 0.0642. The structure is molecular, the metal atom coordinates six oxygen atoms of three ligands of β-diketone. The Ru–O distances are in the range of 1.99 Å to2.03 Å. The complexes have a distorted single layer hexagonal packing with the Ru…Ru distances being 9.84 Å within the layer, and 10.93 Å between the layers.     

Synthesis,structure, and properties of the thermolysis products of [Os(NH<Subscript>3</Subscript>)<Subscript>5</Subscript>Cl][ReCl<Subscript>6</Subscript>]

The crystal structure of [Os(NH₃)₅Cl][ReCl₆] has been refined by X-ray powder analysis: a = 11.645(3) Å, b = 8.3788(2) Å, c = 15.277(4) Å, β = 91.029(6)°, V = 1490(1) ų, d _x = 3.163 g/cm³, space group P2₁/m, Z = 4. The thermolysis product of the salt in a hydrogen atmosphere is a solid substitution solution Os_0.5Re_0.5: a = 2.753(2) Å, c = 4.366(3) Å, space group P6₃/mmc; coherent scattering region (CSR) is ～230 Å.     

Crystal and molecular structure of 2-ferrocenyl-2-propanol

The crystal and molecular structure of 2-ferrocenyl-2-propanol is studied by means of physicochemical methods. The compound crystallizes in the form of three crystallographically independent molecules with slightly different conformations. Crystals are monoclinic, C₁₃H₁₆FeO: a = 6.2687(7) Å, b = 36.614(4) Å, c = 15.291(2) Å; β = 97.86(2)°; V = 3477.2(7) ų, Z = 12, d x = 1.396 g/cm³, P2₁/n space group. The molecule consists of the ferrocene fragment and the isopropyl carbinol substituent.     

Crystal structure of a complex of nickel(II) with 2-amino-4-imino-2-pentene

The structure of a nickel(II) complex with 2-amino-4-iminopentane is determined by X-ray crystallography at 150 K. Crystal data for C₁₀H₁₈N₄Ni are: a = 10.9802(3)Å, b = 13.5780(4)Å, c = 8.0935(2)Å, β = 107.304(1)°, space group P2₁/c, V = 1152.04(5) ų, Z = 4, d _x = 1.459 g/cm³, R = 0.0283. The structure is molecular; the metal atom is coordinated by four nitrogen atoms of two β-diimine ligands. The Ni-N distances in Ni(NacNac)₂ fall within 1.8571–1.8623 Å. The molecules in the crystal are joined by only van der Waals interactions.     

The hydrothermal synthesis and crystal structure of [2.2′-bipyH]<Subscript>3</Subscript>PW<Subscript>12</Subscript>O<Subscript>40</Subscript>

The title compound, [2.2′-bipyH]₃PW₁₂O₄₀, consists of three [2.2′-bipyH]⁺ and one Keggin structure heteropolyanion [PW₁₂O₄₀]^3?, which was hydrothermally synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. It belongs to triclinic system, space group P \(\bar 1\), a = 12.086(3) Å, b = 12.777(4) Å, c = 19.152(4) Å, α = 88.861(2)Å, β = 89.851(3)Å, γ = 67.034(3)Å, M = 3345.72 g/mol, V = 2722.6(12) ų, Z = 2, D _c = 4.081 mg/m³, R₁ = 0.0474, wR ₂ = 0.1135, T = 293(2) K. In this compound, each of the three H⁺ ions locates at between the N atoms in one 2.2′-bipy molecule, respectively. The protonated cations and the heteropolyanion effect each other by the electrostatic force.     

Synthesis and X-ray investigation of Rb<Subscript>2</Subscript>[Pd(NO<Subscript>3</Subscript>)<Subscript>4</Subscript>] and Cs<Subscript>2</Subscript>[Pd(NO<Subscript>3</Subscript>)<Subscript>4</Subscript>]

Powder and single crystal X-ray diffraction studies have been performed for anhydrous nitrate complexes Rb₂[Pd(NO₃)₄] (I) and Cs₂[Pd(NO₃)₄] (II). Crystal data for I: a = 7.843(1) Å, b = 7.970(1) Å, c = 9.725(1) Å; β = 100.39(1)°, V = 597.9(1) Å ³, space group P2₁/c, Z = 2, d _calc = 2.918 g/cm³; for II: a = 10.309(2) Å, b = 10.426(2) Å, c = 11.839(2) Å; β = 108.17(3)°, V = 1209.0(4) ų, space group P2₁/c, Z = 4, d ^calc = 3.408 g/cm³. The structures are formed by isolated [Pd(NO₃)₄]^2? complex anions and alkali metal cations. The plane-square environment of the Pd atom is formed from the oxygen atoms of the monodentate nitrate groups. The geometrical characteristics of the complex anions are analyzed. Compound II has a short contact Pd...Cs 3.252 Å.     

Spectroscopic characterization,X-ray structure and DFT studies on 4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl]-N-methylthiazol-2-amine

The titled molecule 4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl]-N-methylthiazol-2-amine (C₁₇H₂₂N₂S) is synthesized and characterized by ¹H NMR, ¹³C NMR, IR, and X-ray single crystal determination. The compound crystallizes in the monoclinic space group P2_1/c with a = 6.3972(4) Å, b = 9.4988(6) Å, c = 26.016(2) Å and β = 93.496(7)°. In addition to the molecular geometry from the X-ray determination, vibrational frequencies and gauge, including the atomic orbital (GIAO), ¹H and ¹³C NMR chemical shift values of the titled compound in the ground state are calculated using the density functional (B3LYP) method with 6-31G(d), 6-31++G(d,p) and 6-311+G(2d,p) basis sets. The calculated results show that the optimized geometries can well reproduce the crystal structure. Moreover, the theoretical vibrational frequencies and chemical shift values show good agreement with the experimental values. The predicted nonlinear optical properties of the titled compound are greater than those of urea. DFT calculations of the molecular electrostatic potentials and frontier molecular orbitals of the titled compound are carried out at the B3LYP/6-31G(d) level of theory.     

X-ray diffraction structural investigation of two hafnium(IV) complexes with dipivaloylmethane

Synthesis and single crystal X-ray diffraction study of hafnium(IV) dipivaloylmethanate Hf(dpm)₄ and chloro-tris-(dipivaloylmethanato)hafnium(IV) Hf(dpm)₃Cl have been carried out. Crystal data: a = 22.6606(5) Å, b = 11.3990(4) Å, c = 19.8513(7) Å, β = 106.458(1)°, Pc, Z = 4, d _calc = 1.231 g/cm³, R = 0.075 for C₄₄H₇₆HfO₈; a = 10.6376(13) Å, b = 10.6701(10) Å, c = 19.4400(22) Å, α = 74.970(3)°, β = 75.672(3)°, γ = 61.725(2)°, P-1, Z = 2, d _calc = 1.366 g/cm³, R = 0.031 for C₃₃H₅₇ClHfO₆. The structures are molecular and are built from discrete mononuclear complexes joined by van der Waals interactions. Disordering of carbon atoms preserving at low temperature is observed for the compound Hf(dpm)₄. It has been found out that the structure contains two crystallographically unique complexes of hafnium(IV) with central atoms coordinated with eight oxygen atoms of four dipivaloylmethane ligands, bond lengths Hf-O fall within 2.084–2.222 Å, the distances Hf...Hf between the molecules are 10.07–13.87 Å. In Hf(dpm)₃Cl the hafnium atom is seven-coordinated with six oxygen atoms of three β-diketonate ligands and one chlorine atom, the distances Hf-O fall within 2.087–2.179 Å, the lengths of the bond Hf-Cl for two crystallographically independent molecules Hf(1) and Hf(2) are 2.466 Å and 2.442 Å, respectively.