Question of the complexation of tetrachlorostannane with benzyl chloride

Conclusion The condensation of PhCH₂Cl with the liberation of HCl catalyzed by SnCl₄, occurs in the PhCH₂Cl-SnCl₄. system. The proposal of the existence of a cis-octahedral complex, 2PhCH₂Cl· SnCl₄, was proved erroneous.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2336–2337, October, 1987.     

Reactions of iridium bis(phosphinite) pincer complexes with protic acids

Iridium pincer complexes [C₆H₃-2,6-(OPBu^t ₂)₂]Ir(H)Cl (10) and [4-EtOOCC₆H₂-2,6-(OPBu^t ₂)₂]Ir(H)Cl (11) react with protic acids undergoing metallation of one of the tert-butyl groups to form double cyclometallated products [4-R-C₆H₂-2-(OPBu^t ₂)-6-(OP(Bu^t)CMe₂CH₂)]IrCl (12, R = H; 13, R = COOEt), which are stable in air. Complex 12 reacts with CO and Bu^tNC giving the corresponding 18-electron complexes [C₆H₃-2-(OP-Bu^t ₂)-6-(OP(Bu^t)CMe₂CH₂)]Ir(L)Cl (14, L = CO; 15, L = CNBu^t). The structure of compound 14 was established by X-ray diffraction analysis.     

Synthesis and structure of silyl-substituted imidazol-2-ylidenes and their precursors

Previously unknown heterocyclic carbenes and their precursors containing a silicon atom in the side chain were prepared. Their structures were studied by multinuclear ¹H, ¹³C, ¹⁵N, and ²⁹Si NMR spectroscopy.     

MNDO refinement of the Townes-Dailey theory. Calculation of NQR frequencies of chloro-containing compounds

Corrections accounting for the effect of the differences in p-electron energies on the electric field gradient are suggested and justified in the framework of Townes-Dailey theory. MNDO calculations of 31 chloro-containing molecules with full geometry optimization were used to evaluate the³⁵Cl NQR frequencies. The correlational relationships between experimental and calculated NQR frequencies are compared.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 38–42, January, 1995.This work was supported by the Russian Foundation for Basic Research (Project No. 93-03-5201).     

Peculiarities of the complexation of copper and silver adducts of a 3,5-bis(trifluoromethyl)pyrazolate ligand with organoiron compounds

Interaction of the copper, {[3,5-(CF(3))(2)Pz]Cu}(3), and silver, {[3,5-(CF(3))(2)Pz]Ag}(3), macrocycles [3,5-(CF(3))(2)Pz = 3,5-bis(trifluoromethyl)pyrazolate] with cyclooctatetraeneiron tricarbonyl, (cot)Fe(CO)(3), was investigated by IR and NMR spectroscopy for the first time. The formation of 1:1 complexes was observed at low temperatures in hexane. The composition of the complexes (1:1) and their thermodynamic characteristics in hexane and dichloromethane were determined. The π-electron system of (cot)Fe(CO)(3) was proven to be the sole site of coordination in solution and in the solid state. However, according to the single-crystal X-ray data, the complex has a different (2:1) composition featuring the sandwich structure. The complexes of ferrocene with copper and silver macrocycles have a columnar structure (X-ray data).     

Synthesis and comparative X-ray diffraction study of first ruthenocene-based pincer palladium complexes, PdCl[{2,5-(But 2PCH2)2C5H2}Ru(Cp′)] (Cp′ = C5H5 or C5Me5)

First ruthenocene-based palladium complexes PdCl[{2,5-(Bu^t ₂PCH₂)₂C₅H₂} Ru(Cp′)] (Cp′ = C₅H₅ (4) or C₅Me₅ (5)) were synthesized. Comparative single-crystal X-ray diffraction study of complexes 4 and 5 showed that the deviations of the cyclopentadienyl rings in these complexes from being parallel are 2.6 and 10.1°, respectively. In addition, the shift of the palladium atom relative to the plane of the metallated cyclopentadienyl ligand is 0.007 Å for 4 and 0.336 Å for 5. These differences in the structures of complexes 4 and 5 are due to close contacts between the pseudoequatorial tert-butyl groups at the phosphorus atoms and the unmetallated cyclopentadienyl ring. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1879–1884, November, 2006.     

A study of the hydrogen bond by means of comparative calculations

The nature of the hydrogen bond is investigated by means of a comparative analysis of some hydrogen bonded and hydrogen-like bonded systems. It is concluded that the hydrogen bond is determined by electrostatic interaction between the proton and the region of high electron density in the neighbour molecule.     

Cross-sections for deuteron photo-disintegration from 139 to 832 MeV

The cross-sections for deuteron photo-disintegration have been measured at nine c.m. angles from 37 to 143 degrees. The minimum and maximum photon energies have been 139 and 832 MeV respectively. The results are in agreement with earlier data above 300 MeV, but are significantly larger below 200 MeV, the discrepancies being up to 50% at the lowest energies measured.