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In the crystal structure of (CH2C1)2P(O)CH3 and the isomorphous crystal structures of (CH2Br)2P(O)CH3 and (CH2I)2P(O)CH3, the molecules of the methylbis(halomethyl)phosphine oxide have an identical trans, gauche conformation.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1526–1528, July, 1991. 相似文献
5.
V. I. Evreinov V. E. Baulin Z. N. Vostroknutova Z. V. Safronova I. B. Krashakova V. Kh. Syundyukova E. N. Tsvetkov 《Russian Chemical Bulletin》1991,40(9):1759-1766
Stability constants of complexes of alkali-metal cations with oligoethylene glycol diethers RO(CH2CH2O)nR (n=1–5), where R=2-Ph2P(O)C6H4 and 2-Ph2(O)-4-t-BuC6H3P, have been determined conductometrically in a tetrahydrofuran-chloroform mixture (41 by volume). The dependence of complexing ability on a number of monopodand donor centers for Li+ and Na+ has multiple extrema. For K+, Rb+, and Cs+ the complexing abilities steadily increase with the length of the ligand polyether chain. Monopodands based on triethylene glycol and its pyrocatechol analog are highly effective (log K=6.7–7.0) with respect to Li+. The synthesis of ligands with a lipophilic tert-butyl substituent in the terminal group is described.For previous communication, see [1]. The number of the communication in [2] is 5, not 4 as printed in error.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1992–2000, September, 1991. 相似文献
6.
V. V. Azatyan N. M. Rubtsov G. I. Tsvetkov V. I. Chernysh 《Kinetics and Catalysis》2006,47(3):327-332
The interaction of hydrogen atoms with a variety of alkali metal and alkaline-earth metal salts results not only in the recombination of these atoms but also in the displacement, into the gas phase, of free radicals (CaCl·(A 1 P 1/2, B 2 S +) and CaF·(A 2 P)) and metal atoms, including their excited species, which are detected spectroscopically. Transmission spectra indicate that the NaCl surface undergoes metallization when treated with a high-frequency discharge and a rarefied hydrogen flame. Combustion is affected by the gas-phase hydrogen atoms involved in the chain reaction and by the varying composition and properties of the surface. The concentration of Na atoms over the NaCl surface at 770 K is 109?1011 cm?3 in a stream of H atoms at 1 Torr and in the 2H2 + O2 flame at 4 Torr. The concentration of sodium atoms in the 2 P 3/2 and 2 P 1/2 excited states is ~5 × 106?5 × 108 cm?3. The role of the discovered reactions in combustion, pyrolysis, and plasma chemistry is discussed. 相似文献
7.
S.A. Dikanov V.F. Yudanov R.I. Samoilova Yu.D. Tsvetkov 《Chemical physics letters》1977,52(3):520-525
Data on the trapping site of radicals in zeolite α-cages have been obtained by the analysis of modulation effects in the electron spin echo of CH2OH radicals produced by irradiation in A-type zeolite with adsorbed methyl alcohol. 相似文献
8.
A method is described for the synthesis of phosphorus-containing amino carboxylic acids, by the Michaelis-Bekker or Arbuzov phosphorylation of -haoalkylacetamidomalonic esters. The latter were obtained by alkylating the sodium salt of acetamidomalonic ester with an excess of the ,-dihaloalkane. Acid hydrolysis of the phosphorus-containing alkylacetamidomalonic esters gave the required compounds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2590–2595, November, 1989. 相似文献
9.
Electron spin echo modulation effects have been investigated in trans bis(2,2,5,5-tetramethyl-3-imidazoline-3-oxide-1-oxyl-4-il) ethylene biradicals involving 14N or 15N nuclei in different positions. The modulation frequencies are shown to be the nitrogen nuclear transition frequencies in radical fragments at mS = 0 of a triplet electronic spin. Quadrupole splitting parameters for these nitrogen nuclei have been determined. 相似文献
10.
A. N. Bovin V. I. Evreinov Z. V. Safronova E. N. Tsvetkov 《Russian Chemical Bulletin》1993,42(5):912-916
A number of monopodands havingo-diphenylphosphinyl terminal groups were synthesized by alkylating sodium derivatives of oligoethylene glycols witho-(bromomethyl)phenyldiphenylphosphine. The stability constants of the complexes of these ligands with alkali metal cations at 25 °C were determined conductometrically in a THF—chloroform solution (41, v/v). The complexing ability of monopodands with respect to the cations studied increases monotonically as the number of electron-donating sites increases (from 3 to 8) for all of the cations except Li+ and, to some extent, Na+. In the case of Li+ a smooth decrease in the stability of the complexes is observed. The monopodands obtained in this work differ drastically in this regard from their structural isomers, bis[o-(diphenylphosphinylmethyl)phenyl] ethers of oligoethylene glycols, which had been studied previously.For part 10, see ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 952–956, May, 1993. 相似文献