Reaction of esters of thio acids of trivalent arsenic with organomagnesium compounds

Conclusions Depending on the molar ratios, the esters of the thio acids of trivalent aresnic are alkylated by organomagnesium compounds to give the corresponding tertiary arsines or the esters of the thio acids of trivalent arsenic.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 963–965, April, 1972.     

Methane conversion with carbon dioxide on nickel aluminides

The catalytic activity of several samples based on nickel aluminides in methane conversion with carbon dioxide was studied. Nickel aluminides were prepared by the method of self-propagating high-temperature synthesis. The Ni₃Al system containing the nickel metal phase exhibited high activity at temperatures above 1073 K. The systems based on Ni₂Al₃ and NiAl only containing intermetallic compound phases were inactive.     

Synthesis of 4-Formyl-3-cyclopentene-1,1,2-tricarbonitriles

β,β,γ,γ-Tetracyanoalkanones react with acrolein at a high rate to afford the corresponding 2-substituted 4-formyl-3-cyclopentene-1,1,2-tricarbonitriles in high yields. The reaction occurs under mild conditions and is quite applicable for modification of natural and biologically active compounds possessing an R′CHC(O)CR₃ fragment to obtain their derivatives containing three cyano groups.     

Analytical Azo Coupling Reactions: A Quantum-Chemical Consideration

Azo coupling reactions of 1-aminonaphthalene with naphthalene-1-diazonium and 4-sulfobenzene-diazonium cations are studied by quantum chemistry. It is found that the reactions are orbital controlled and their regioselectivity is unambiguously governed by the thermodynamic properties of the intermediate σ-complexes and by the effect of the aqueous medium. The latter causes high site selectivity, providing the choice of one of the two possible reaction channels predicted on the basis of quantum-chemical calculations of the isolated molecular systems. As a result, azo coupling occurs at the 4-position of the 1-aminonaphthalene molecule. Additionally, the aqueous medium provides the selection of analytical forms, namely, the protonated azo coupling products that have the quinone-hydrazone structure. On the basis of the quantum-chemical study, the analytical performances of the two azo coupling reactions mentioned above are discussed.     

Cyclocondensation of [1-Cyano-2-(methylsulfanyl)vinyl]triphenylphosphonium Iodide with Amidine Nucleophiles

The substituted vinylphosphonium salt (E)-MeSCH=C(CN)P⁺Ph₃I⁻ readily cyclizes under the action of benzamidine and 3-amino-s-triazole, but it does not enter cyclocondensation with 2-aminopyridine. The structure of the cyclization product with 3-amino-s-triazole was confirmed by its transformation to 7-imino-6-(triphenylphosphoranylidene)-6,7-dihydro-s-triazolo[1,5]pyrimidine which was identified by X-ray diffraction. This stabilized ylide and its analogs proved useful starting materials for regioselective syntheses of 2-R-4-alkyl-4,7-dihydro-s-triazolo[1,5-a]pyrimidin-7-ones.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 4, 2005, pp. 565–570.Original Russian Text Copyright © 2005 by Smolii, Muzychka, Chernega, Drach.     

Electron impact mass spectral interpretation for some thiophosphoryl-p-acetylaminobenzenesulfonamides

This work discusses the synthesis and the fragmentation patterns for 2-(p-acetylaminosulfonamido)-2-thiono-(5,5-dimethyl-1,3,2-dioxaphosphorinane)(1) and for the p-acetylaminosulfonylamides of O,O-diethylthiophosphoric acid (2), O,O-diphenylthiophosphoric acid (3), dimethylaminocyclohexylthiophosphoric acid (4), and diethylaminophenylthiophosphoric acid (5). A thionamidic-thiolimidic structure was attributed to compounds 1-5, consistent with their IR and NMR spectra. EI mass spectra at 70 eV, high resolution (HR) mass measurements and metastable ion spectra were used to elucidate the fragmentation processes and to determine the kinetic energy release values associated with the metastable ion dissociations. HR accurate mass measurements were used to confirm the compositions of the more abundant ions.     

Spectrophotometric determination of bismuth after extraction of hexadecyltributylphosphonium tetraiodobismuthate(III) by microcrystalline benzophenone

Bismuth (0–110 μg) is determined spectrophotometrically at 495 nm after its adsorptive extraction from dilute sulphuric acid as hexadecyltributylphosphonium tetraiodobismuthate(III) on microcystalline benzophenone and dissolution of the solid phase in carbon tetrachloride. The effects of acidity, diverse ions and masking studies are reported. The system is applied to the determination of bismuth in pharmaceutical samples.     

Dependence of the reactivity of allophanates on the conformation of the main chain

The CNDO/2 method was used to investigate the conformation and structure of alkylsubstituted allophanates. The possibility of the existence of isomers both with coplanar and with noncoplanar main chains NCNC was studied. It was shown that the formation of conformers with a cis-structure of the ester group is more probable. On the basis of an analysis of the dependence of the reactivity on the structure of the main chain, hypotheses were advanced on the role of the more stable conformers in various channels of polyaddition of isocyanates.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 22, No. 3, pp. 360–363, May–June, 1986.     

Chemistry of 1,5-diketone derivatives. 1. Oxidation of 8a-methoxy-4a,5,6,7,8,8a-hexahydrochromenes by monoperphthalic acid

2-(2-Oxo-3-hydroxy-1,3-diphenylpropyl)cyclohexanone, 2-(2,3-dioxo-1,3-diphenylpropyl)cyclohexanone, and 2-benzyl-7a-hydroxy-3-phenylperhydrobenzofuran are formed by the action of monoperphthalic acid on 8a-methoxy-2,4-diphenyl-4a,5,6,7,8,8a-hexahydrochromene. Under analogous conditions, 4a-methoxy-10-phenyl-1,2,3,4, 4a,6,7,8,9,10a-decahydroxanthene forms 7a-hydroxy-3-phenyloctahydrobenzo[b]furan-2-spiro-1-cyclohexan-2-one and its dehydration product. The behavior of the compounds obtained toward acetic anhydride and a methanolic solution of HCl was studied. The configurations of the reaction products and the reaction path are considered.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 177–181, February, 1985.