Structure and reactions of benzo-4-diphenylphosphino-2-phenyl-1,3,2-dioxaborinane

The crystal structure of 5,6-benzo-4-diphenylphosphino-2-phenyl-1,3,2-dioxaborinane 1 indicates the occurrence of an interaction between the π-systems of the 1,3,2-dioxaborinane ring and the appropriate phenyl group of the diphenylphosphino group. Complexes of compound 1 with PtCl₂, PdCl₂, and Cul were synthesized. Compound 1 and its complexes are readily hydrolyzed in solution to give diphenylphosphine and its corresponding complexes (NMR).     

Crystal and molecular structure of aroyl- and acetylhydrazones of acet- and benzaldehydes

Aroyl- and acetylhydrazones of acet- (I) and benzaldehydes (IV) and benzoylhydrazones of acet- (II) and benzaldehydes (III) were studied by x-ray structural and quantum-chemical methods in order to establish their structures. Compund (I) was the EEZ structure in the crystal. Calculations and spectral data showed that the EEE form occurs in nonpolar solvents and in the gas phase. According to crystallographic data molecules (I)–(IV) are the E-isomers (relative to the N-N bond) and the hydrazone fragments are planar. Intermolecular N-H...O H-bonds from in the crystals. The data obtained suggest that the majority of acylhydrazones are conformationally rigid on dissolution although exceptions do occur. Apparently the reasons for the difference of acetyl- and benzoylhydrazones in electrocarboxylation reactions are electronic and not steric factors.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 75–81, January, 1991.     

The Influence of Solvents on the Alkylation of Carboxylate Phosphabetaines with Alkyl Iodides

The new alkylation reactions of a series of mono- and dicarboxylate phosphabetaines with methyl and ethyl iodides in different solvents have been studied. These reactions have afforded stable compounds: iodine-containing salts of phosphonium with different structure.     

Molecular structure of 2,9-dioxo-1,3,8,10-tetraoxa-2,9-dithiacyclotetradeca-5,12-diyne

Conclusions The heterocycle 2,9-dioxo-1,3,8,10-tetraoxa-2,9-dithiacyclotetradeca-5,12-diyne has a conformation of C₂ symmetry in the crystal; the acetylene fragments intersect at an angle of 20.8°. The bond lengths and the endocyclic valence angles are close to their standard values.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2750–2753, December, 1987.     

New phosphonium salts based on 3-(diphenylphosphino)propanoic and ω-haloalkanoic acids

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Synthesis of cobalt-containing nanoparticles by cobalt formate thermolysis in hydrocarbon oil without stabilizing ligands

A simple and available method is proposed for the synthesis of cobalt-containing nanoparticles. This method comprises cobalt formate thermolysis in hydrocarbon oil without extra stabilizing ligands. The size, composition, and structure of the nanoparticles are determined by transmission electron microscopy, X-ray powder diffraction, and electron diffraction. The average particle size is 10–14 nm. The major components are cobalt oxides CoO and Co₃O₄. Apart from these oxides, the particles contain minor metallic cobalt.