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21.
A polyphosphide of the type (NaP)X 1 was obtained from red phosphorus and sodium in presence of small amounts of naphthalene in 1,2-dimethoxyethane as solvent. 1 reacts with alkyl halides in dependence on the kind of alkyl group with formation of different alkylcyclophosphanes. As definite compounds Me5P5 2 , Et5P5 3 (with not definite constitution), i-Pr4P4 4 and t-Bu4P4 5 could be isolated. 1 was identified by X-ray diffraction, 2 – 5 by means of their 1H, 13C, 31P n.m.r. and mass spectra. The molecular structure of 4 was identified by electron diffraction. 相似文献
22.
23.
Malashenko Y. R. Sokolov I. G. Muchnik F. V. Plnchuk G. E. 《Applied biochemistry and biotechnology》1994,45(1):449-452
Applied Biochemistry and Biotechnology - Considering the process of methane generation by methanogenic bacteria as an example, the model describes the distribution of methane concentration inside... 相似文献
24.
25.
A. A. Potekhin V. V. Sokolov A. A. Tomashevskii 《Chemistry of Heterocyclic Compounds》1988,24(10):1185-1186
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, p. 1424, October, 1988. 相似文献
26.
The solid-state reactions of crystalline ferrocenyl- and ruthenocenylaldehydes with optically active primary β-hydroxyamines
were studied at ∼20 °C. The yield of the products increases substantially in the presence of K2CO3. The tautomeric equilibrium between imines and diastereomeric oxazolidines with the predominant formation of one of them
is established in solutions of the products in CDCl3.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2240–2243, December, 1997. 相似文献
27.
V. A. Cherepenin S. A. Sokolov V. A. Vdovin 《International Journal of Infrared and Millimeter Waves》1987,8(9):1119-1128
A relativistic, two-wave generator working near -type oscillations of two lowest modes with frequency band around 8 mm, is investigated experimentally. Obtained output radiation patterns point to a single-frequency radiation character. The efficiency is found to rise in two-wave regimes in comparison with one-wave ones. The generator assembled of two sections is also considered. 相似文献
28.
S. D. Sokolov T. N. Egorova P. V. Petrovskii 《Chemistry of Heterocyclic Compounds》1974,10(5):516-520
The 4-nitro derivative is formed in the nitration of 3,5-diphenylisoxazole (I) in acetic anhydride. Mononitration of isoxazole I in concentrated H2SO4 gave 3-phenyl-5-(p-nitrophenyl)isoxazole, while polynitration gave a mixture of dinitro derivatives, among which 3- (m-nitro-phenyl)-5-(p-nitrophenyl)isoxazole was identified. The structures of the isolated products were established by means of the spectra, by reaction-chromatography methods, and gasliquid chromatography, as well as by a comparison with genuine samples of the two mononitro and four dinitro derivatives of isoxazole I. 相似文献
29.
B. L. Tumanskii V. V. Bashilov N. N. Bubnov S. P. Solodovnikov V. I. Sokolov 《Russian Chemical Bulletin》1994,43(5):884-886
Using ESR spectroscopy, the reaction of P(O)(OPri)2 phosphoryl radicals with C60ML2 (M=Pd, Pt) was studied and the spin-adducts formed were shown to be unstable under the reaction conditions. The 5-addition of Pt(PPh3)4 to the dimer of phosphorylfullerenyl radicals results in metal-containing dimers (RO)2(O)PL2MC60-C60ML2P(O)(OR)2, which dissociate when exposed to visible light to afford C60ML2P(O)(OR)2 radicals; ML2 in these complexes is located in different positions in relation to the radical center. As a result, the ESR spectra contain the superposition of at least five signals of radicals that differ in HFS constants andg-factors.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 938–940, May, 1994.The present work was supported by the Russian Foundation for Basic Research (Projects 93-03-18725 and 93-03-4101). 相似文献
30.
I. G. Markova S. M. Vinogradova S. D. Sokolov 《Chemistry of Heterocyclic Compounds》1980,16(10):997-1000
The indicated compounds are reduced on a dropping-mercury electrode in aqueous alcohol solutions at pH > 7 in one two-electron wave to 1,2-disubstituted hydrazines; four-electron reduction with the formation of amines takes place in acidic media. Two one-electron reduction waves are observed in dimethylformamide (DMF). Satisfactory E1/2– correlation equations were obtained for 4-arylazo-3,5-dimethyloxazoles.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1320–1323, October, 1980. 相似文献