Crystal structure and spectral characteristics of {[(C6H5)NH]2C=NH(C6H5)}[B(C6H5)4]·C2H5OH

A novel compound of {[(C₆H₅)NH]₂C=NH(C₆H₅)}[B(C₆H₅)₄]·C₂H₅OH is prepared and examined by single crystal X-ray diffraction. Crystal data: C₄₅H₄₄BN₃O, M = 653.64, monoclinic, space group P2₁/c, unit cell parameters: a = 24.375(2) Å, b = 17.5829(15) Å, c = 18.090(1) Å, β = 105.277(2)°, V = 7479.0(11) ų, Z = 8, d _calc = 1.161 g/cm³, T = 293 K, R ₁ = 0.064. The structure contains two crystallographically independent cations, two anions, and two solvate ethanol molecules. Three types of interactions occur between them: interionic N-H(N)⋯π and N(H)⋯π⋯H(C), π-delocalized system of Ph rings of the anions, and interaction of ions with ethanol molecules N-H⋯O-H(O)⋯π. The compound is characterized by IR and luminescence spectra. At room temperature, the emission intensity grows with time of exposure to UV irradiation. Original Russian Text Copyright ? 2008 by T. M. Polyanskaya, E. A. Il’inchik, V. V. Volkov, M. K. Drozdova, O. P. Yur’eva, and G. V. Romanenko __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 3, pp. 512–521, May–June, 2008.     

Synthesis and crystal structures of [UO2(C6H4NO2)2(C6H5NO2)] and [UO2SO4(C6H5NO2)(H2O)] · H2O

The complexes [UO₂(C₆H₄NO₂)₂(C₆H₅NO₂) (I) and [UO₂SO₄(C₆H₅NO₂)(H₂O)] · H₂O (II) were synthesized and studied by X-ray diffraction analysis. Crystals I are monoclinic: a = 7.0081(3), b = 14.9624(7), c = 9.1837(5) ?, β = 96.594(2)°, Z = 2, space group P2₁/m. Crystals II are triclinic: a = 6.8097(6), b = 9.3837(8), c = 10.4556(10) ?, α = 85.279(3), β = 75.434(3), γ = 69.180(3)°, Z = 2, space group . The main structural unit of crystal I is a mononuclear fragment, which belongs to the crystal chemical group AB ₂ ⁰¹ M¹ (A = UO ₂ ²⁺ , B⁰¹ are ions of pyridine-2-carboxylic (picolinic) acid, M¹ are molecules of picolinic acid) of the uranyl complexes. The main structural unit of crystal II is a chain, which belongs to the crystal chemical group AT³M ₂ ¹ (where T³-SO ₄ ²⁻ , M¹ are water and picolinic acid molecules) of the uranyl complexes. Picolinic acid in complexes I, II was found to have a zwitterion structure. Original Russian Text ? E.V. Grechishnikova, E.V. Peresypkina, A.V. Virovets, Yu.N. Mikhailov, L.B. Serezhkina, 2007, published in Koordinatsionnaya Khimiya, 2007, Vol. 33, No. 6, pp. 468–475.     

Synthesis and crystal structure of (C3N5H6S)2[UO2(C2O4)2(H2O)] · C2N4H4

The formation of the thioammelinium cation in an aqueous solution in the presence of uranyl ions is demonstrated. Single crystal X-ray diffraction study of (C₃N₅H₆S)₂[UO₂(C₂O₄)₂(H₂O)] · C₂N₄H₄ was carried out and the geometric characteristics of thioammelinium were determined for the first time. The crystals are triclinc, space group , Z = 2, a = 8.5201(11) ?, b = 11.4027(14) ?, c = 14.329(2) ?, α = 103.182(5)°, β = 99.607(6)°, γ = 109.698(4)°, R = 0.0526. The main structural units in the crystal are mononuclear complex groups [UO₂(C₂O₄)₂(H₂O)]²⁻ corresponding to the crystal chemical group AB ₂ ⁰¹ M¹ (A = UO ₂ ²⁺ , B⁰¹ = C₂O ₄ ²⁻ , M¹ = H₂O) of uranyl complexes. Uranium-containing mononuclear complexes are connected into a three-dimensional framework through electrostatic interactions and hydrogen bonds involving thioammelinium ions, water molecules, and cyanoguanidine. Original Russian Text ? L.B. Serezhkina, A.V. Virovets, E.V. Peresypkina, I.V. Medrish, 2007, published in Koordinatsionnaya Khimiya, 2007, Vol. 33, No. 5, pp. 380–385.     

Large-bite bisphosphite, 1,3-C6H4{OPOC10H6(μ-S)C10H6O}2: Synthesis, copper(I), and gold(I) complexes

Large-bite bisphosphite ligand 1,3-C₆H₄{OPOC₁₀H₆(μ-S)C₁₀H₆O}₂ (3), is obtained by reacting chlorophosphonite {OC₁₀H₆(μ-S)C₁₀H₆O}PCl (2) with resorcinol in the presence of triethylamine. Treatment of 3 with CuCl in 1:1 molar ratio produces a 1D-coordination polymer [CuCl{(-OC₁₀H₆(μ-S)C₁₀H₆O-)P(-OC₆H₄O-)P(-OC₁₀H₆(μ-S)C₁₀H₆O-)}-κP,κP]_∞ (4) in good yield. Similar reaction of 3 with two equivalents of AuCl(SMe₂) affords a dinuclear complex, [Au₂Cl₂{(-OC₁₀H₆(μ-S)C₁₀H₆O-)P(-OC₆H₄O-)P(-OC₁₀H₆(μ-S)C₁₀H₆O-)}-κP,κP] (5). Single crystal X-ray structures of the ligand 3 and the complexes 4 and 5 are reported. The gold complex 5 shows dimeric structure supported by strong Au···Au aurophilic interactions.     

配合物Zn(C3H4N2)2(C8H6O2Br)2的水热合成、晶体结构及性质

在140℃下,以3-溴-4-甲基苯甲酸和咪唑为配体,通过水热法在甲醇/水混合溶剂中反应24 h合成了锌(Ⅱ)配合物Zn(C3H4N2)2(C8H6O2Br)2。通过元素分析、红外光谱、热重分析和X射线粉末衍射对配合物进行了结构表征,同时用X射线单晶衍射分析确定了其晶体结构。结果表明,其晶体属单斜晶系,空间群为C2/c,晶胞参数:a=13.257(3),b=9.765(2),c=20.494(4),β=107.79(3)°,V=2526.3(9)3,Dc=1.655g·cm-3,μ=4.170mm-1,F(000)=1248,Z=4,最终残差因子R1=0.0552,wR2=0.1378。配合物为单核结构,中心锌(Ⅱ)离子与来自2个3-溴-4-甲基苯甲酸根的2个O原子及2个咪唑分子的2个N原子配位,形成了畸变的四方锥几何体。晶体内,分子间则通过N—H…O氢键作用在ab面形成了层状结构。研究了配合物的发光性质。     

[Ni(C6H4N2)(CHC6H4O)2]配合物晶体结构及性质

The complex has been synthesized and characterized by spectroscopic techniques and single-crystal X-ray analysis. The crystal is orthorhombic ， space group P2₁2₁2₁ with a=1.6620(3)nm， b=1.7300(4)nm， c=0.5450(1)nm and Z=4. In the crystal lattice， the molecules create a two-dimensional network structure through hydrogen bonds. The C-H…O intermolecular hydrogen bonds connect the title complex to form layer super-molecular plane structure perpendicular to the axis b， with the layers stacked by the Van der Waals interaction. CCDC： 195309.     

双核Fe配合物[(η5-C5H4)C6H10(C4H3S)Fe(CO)2]2的合成和晶体结构

由侧链带有噻吩的环戊二烯基配体C5H5C6H10C4H3S与Fe(CO)5在二甲苯中加热回流,合成了1个新颖的四羰基二铁配合物[(η5-C5H4)C6H10(C4H3S)Fe(CO)2]2。通过元素分析、IR、1H NMR对其结构进行了表征,用X-射线单晶衍射确定了其结构。X-射线单晶衍射表明配合物中有2个桥羰基和2个端羰基,Fe-Fe的键长为0.25465(10)nm。     

混配配合物[Zn(C6H5COCHCOCF3)2(C5H4NOH)]的合成、晶体结构及表征

用醋酸锌、苯甲酰三氟丙酮和3-羟基吡啶在甲醇介质中反应合成了混配配合物[Zn(C₆H₅COCHCOCF₃)₂(C₅H₄NOH)]，用元素分析、红外光谱、核磁共振氢谱和热重分析等技术对其进行了表征，并用X-射线单晶衍射仪测定了其晶体结构。该晶体属于三斜晶系，空间群为P1。配合物中锌离子位于四方锥的中心，2个苯甲酰三氟丙酮基负离子以烯醇式一价阴离子形式与锌离子发生双齿配位，配体3-羟基吡啶上的芳氮原子与锌离子发生单齿配位，形成五配位环境的4O+N型混配配合物。     

Functionalised tetraarylstannanes Sn[C6H4-R]4 (R=-CH(CH2O)2, -CHO, -COOH, -CHN-NH-C6H3-2,4-(NO2)2, -CH2OH, -CO-NH-CH2-COO-CH3, -CH[N(C2H4)2O]2)

Reaction of tin tetrachloride with the appropriate Grignard reagent gave Sn[C₆H₄-CH(OCH₂)₂]₄ (2), which was transformed to Sn[C₆H₄-CHO]₄ (3) and its hydrazido and amino derivatives Sn[C₆H₄-CHN-NH-C₆H₃-2,4-(NO₂)₂]₄ (5) and Sn{C₆H₄-CH[N(C₂H₄)₂O]₂}₄ (8). Oxidation of (3) produced Sn[C₆H₄-COOH]₄ (4) while reduction of (3) gave Sn[C₆H₄-CH₂-OH]₄ (6). From the acid 4, an amino acid Sn[C₆H₄-CO-NH-CH₂-CO-OCH₃]₄ (7) could be obtained by reaction with the methyl ester of glycine. All compounds were isolated in pure form with yields of 40-64% and were characterised by spectroscopic means (heteronuclear NMR) or by X-ray structure determination (3).     

Synthesis of (C8H11N)2·Zn(OAc)2, (C8H11N)2·Cu(OAc)2, and (C8H11N)2·CuCl2 complexes and application to the Henry reaction

(C₈H₁₁N)₂·Zn(OAc)₂ (1a), (C₈H₁₁N)₂·Cu(OAc)₂ (1b), and (C₈H₁₁N)₂·CuCl₂ complexes are synthesized by a simple one-pot method. The crystal structures of 1a, 1b, and 1c are determined by X-ray crystallography. The complexes are also characterized by NMR, IR, MS, and elemental analysis and used as the catalysts applied to the Henry reaction; moderate to high yields are obtained at room temperature.     

Singlet-triplet energy separation in divalent seven-membered cyclic conjugated compounds C6H6C, C6H6Si, C6H6Ge, C6H6Sn, and C6H6Pb

The electronic and thermal energy differences, ΔE(t-s); enthalpy differences, ΔH(t-s); and free energy differences between the singlet and triplet states, ΔG(t-s), were calculated for C₆H₆C, C₆H₆Si, C₆H₆Ge, C₆H₆Sn, and C₆H₆Pb at the B3LYP/6-311++G (3df, 2p) level. The singlet-triplet splitting, G _s-t, of C₆H₆C, C₆H₆Si, C₆H₆Ge, C₆H₆Sn, and C₆H₆Pb generally increased from C₆H₆C toward C₆H₆Pb. The most stable tautomers and conformers were suggested for the singlet and triplet states of C₆H₆M (M = C, Si, Ge, Sn and Pb). The geometrical parameters were calculated and discussed. The text was submitted by the authors in English.     

Stabilization Studies on Divalent Five‐Membered Rings C4H4C,C4H4Si,C4H4Ge,C4H4Sn,and C4H4Pb

Energy differences, ΔX_S‐t (X = E, H and G) (ΔX_S‐t = X_(singlet)‐X_(triplet)) between singlet (s) and triplet (t) states are calculated at B3LYP/6‐311++G (3df,2p). The DFT calculations show that the triplet state of C₄H₄C is a ground state with planar conformer respect to its corresponding nonplanar singlet state. Both singlet and triplet states of C₄H₄M (M = Si, Ge, Sn and Pb) have a planar conformer with the singlet ground state. Four isodesmic reactions are presented for determining the stability energies, SE. NICS calculations are carried out for C₄H₄M to determine the aromatic character.     

Singlet-triplet energy separations in divalent five-membered cyclic conjugated C5H3X, C4H3SiX, C4H3GeX, C4H3SnX, and C4H3PbX (X = H, F, Cl, and Br)

Singlet-triplet energy gaps in cyclopenta-2,4-dienylidene, as well as its 2- or 3-halogenated derivatives, are compared and contrasted with their sila, germa, stana, and plumba analogues; at HF/6-31G* and B3LYP/ 6-311++G(3df, 2p) levels of theory. Energy gaps (ΔG_t-s), between triplet (t) and singlet (s) states, appear linearly proportional to: (i) the size of the group 14 divalent element (M = C, Si, Ge, Sn and Pb), (ii) the angle ∠C-M-C, and (iii) the ΔG_(LUMO-HOMO) of the singlet state involved. The magnitude of ΔG_t-s, for each 2- and/or 3-substituted species studied, increases with an order of: carbenes < silylenes < germylenes < stanylenes < plumbylenes. This order reverses for the barriers of the ring puckering. The puckering occurs with more ease for every singlet, compared to its corresponding triplet form.Regardless of the group 14 element (M) employed, every 3-halo-substituted species is more stable than the corresponding 2-halo-substituted isomer. For M = Pb, Sn and/or Ge; 3-halo-substituted species have higher ΔG_t-s than their corresponding 2-halo-substituted analogues. For M = Si, similar ΔG_t-s are found for 2- and 3-halogenated isomers. For M = C, 3-halo-substituted species have lower ΔG_t-s than their corresponding 2-halo-substituted analogues.Every cyclic singlet has a larger ∠C-M-C angle, than its corresponding cyclic triplet state, except for 3-halosilacyclopenta-2,4-dienylidenes where triplet has a larger ∠C-M-C angle than its corresponding singlet state.     

Singlet–triplet splitting and stability of divalent five‐membered ring C4H4M,C4H6M,and C4H8M (M = C,Si, Ge,Sn, and Pb)

The sum of electronic and thermal free energy differences between singlet and triplet states (Δ G_t‐s) is calculated for C₄H₄M, C₄H₆M, and C₄H₈M (M = C, Si, Ge, Sn, and Pb) at B3LYP/6‐311++G (3df,2p) level. Singlet–triplet splitting (Δ G_t‐s) is compared for three analogs C₄H₄M, C₄H₆M, and C₄H₈M. The change order of Δ G_t‐s is (except for M = C) C₄H₆M > C₄H₈M > C₄H₄M. The results of homodesmotic reaction energies show the most stability for singlet state of C₄H₆M with respect to C₄H₄M and C₄H₈M. In contrast, the triplet state of C₄H₄M (except for M = C) is the most stable with respect to C₄H₆M and C₄H₈M. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:245–251, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20428     

Metallorganische verbindungen des 1,2-diethinylbenzols vom typ o-C6H4(CCMR3)2 (M = Si,Ge, Pb)

The preparation of the compounds o-C₆H₄(CCMR₃)₂ (M = Si, Ge, Pb; R = CH₃; M = Pb; R = C₆H₅) is described. Their properties are compared with those of o-C₆H₄(CCSnR₃)₂ (R = CH₃, C₆H₅) and those of their p-isomers. The structures and bonding conditions proposed for these molecules are supported by dipole measurements, mass spectroscopy, IR, Raman, ¹H NMR and ¹³C NMR data.     

Synthesis, characterization and comparison of group 14 pyrrolides and indolides Ph3MX (M = Si, Ge, Sn; X = C4H4N, C8H6N)

The biologically important heterocycles pyrrole, C₄H₄N, and indole, C₈H₆N, ought to be useful as reagents in organic synthesis. Unfortunately, working with them has proved to be difficult because they tend to self-polymerize in solution, especially in the presence of acid catalysts. When the self-polymerization can be controlled, however, the pyrrole and indole units should provide an important route to selective N-metal binding, particularly when these ligands are activated by alkyl-lithium reagents. Using this approach, a general synthesis of the group 14 pyrrolides and indolides, Ph₃MX (M = Si, Ge, Sn; X = C₄H₄N, C₈H₆N), has been developed and the results are reported here. The compounds are formed as high-melting, white crystalline solids and have been characterized by ¹³C-, ²⁹Si- and ¹¹⁹Sn-NMR, Raman and electron-impact mass spectroscopy as well as elemental analysis. A single-crystal X-ray study of Ph₃Si(C₄H₄N) has shown that the compound is disordered in the tetragonal lattice, even at low temperature (100 K).     

Electric birefringences and solution-state conformations of molecules C6H5SM(CH3)3 ; M = C,Si, Ge or Sn

Dipole moment and electric birefringence studies are reported for the series of molecules C₆H₅SM(CH₃)₃ in cyclohexane solution; M = C, Si, Ge or Sn. The experimental data are analysed to determine the preferred solution-state conformations. The dihedral angles between the C₆H₅ and C_arSM planes are, in turn, 82 ± 11°, 80 ± 11°, 66 ± 12° and 46 ± 10°.     

Multiconfiguration self-consistent wavefunctions for CH4, C2H4 and C2H6

The results of several MC SCF calculations on CH₄, C₂H₄ and C₂H₆ with minimun bases of Slater type AO's are reported. The computing method is a quadratically convergent process. Better final energies are obtained if localized MO's are used.     

Theoretical design of singlet localized σ-diradicals: C(MH2)3C (M = Si, Ge, Sn, Pb)

Some localized singlet 1,3-σ-diradicals, C(MH₂)₃C, (M = Si, Ge, Sn, Pb) were theoretically designed by the orbital phase theory and density functional theory calculations. The bicyclic carbon-centered singlet diradicals were more stable than the lowest triplets. Except for M = C, σ-bonded isomers were not located for 1,3-σ-diradicals. 1,4-σ-diradicals, C(M₂H₄)₃C, also had singlet ground states, but they were less stable than σ-bonded isomers.     

The structure of C2H5InBr2 · tmen,C2H5InI2 · tmen (tmen = N,N,N,′,N′-tetramethylethanediamine) and [(C6H5)4P][C2H5InI3] in solution and in the solid state

The ¹H NMR spectra of C₂H₅InBr₂ · tmen (1) C₂H₅InI₂ · tmen (2) (tmen = N,N,N′,N′-tetramethylethanediamme) and [(C₆H₅)₄P][C₂H₅InI₃] (3) show only a broad singlet for the ethyl protons at 60 MHz. Spectra run at 400 MHz resolve these into a triplet + quartet for 1 and 3. The structure of each compound has been determined by X-ray crystallography; 1 and 2 are five-coordinate species, with InC₂N₂X (X = Br, I) nuclei, while 3 consists of [(C₆H₅)₄P]⁺ cations and anions whose InCI₃ nucleus has C_3v, symmetry.