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1.
V. G. Lakhtin V. L. Ryabkov A. V. Kisin V. M. Nosova M. V. Polyakova E. A. Chernyshev 《Russian Chemical Bulletin》1995,44(11):2163-2167
Liquid-phase chlorination of a number of chloro(chlorovinyl)methylsilanes was investigated. A number of novelC-chlorosilanes were characterized by IR and1H NMR spectra. Some regularities of these reactions were determined; correlations between the structure of chloro(chlorovinyl)methylsilanes and their reactivities were identified.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2256–2260, November, 1995. 相似文献
2.
L. D. Smirnov S. V. Nikitin A. I. Chernyshev A. A. Sorokin V. P. Lezina V. G. Zabrodnyaya M. M. Kaganskii 《Chemistry of Heterocyclic Compounds》1992,28(12):1425-1431
It has been shown that the alkylation of 2-methyl-9-hydroxy-4H-pyrido[1,2-a]pyrimidin-4-one takes place at the oxygen atom, but electrophilic substitution takes place mainly at position 8 of the molecule (the ortho position relative to the hydroxy group).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1660–1666, December, 1992. 相似文献
3.
S. V. Shorshnev S. E. Esipov A. I. Chernyshev A. F. Pozharskii I. M. Nanavyan V. V. Kuz'menko 《Chemistry of Heterocyclic Compounds》1987,23(11):1247-1251
Unlike rheumycin and fervenulin, isofervenulin and 3-methylisofervenulin are hydrolyzed by aqueous alkalies at the N(5)-C(6) bond. On acidification of the reaction mixture, the N-carboxy-N-methylcarbamoyltriazines formed are reconverted into the starting isofervenulins, and on basification (pH>10) into methylaminotriazinecarboxamides. A by-product of the alkaline hydrolysis of isofervenulin is a product of the contraction of the uracil ring, namely imidazotriazinone-7a-carboxylic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1555–1559, November, 1987. 相似文献
4.
5.
6.
Aleinikov N. N. Vasil'ev G. K. Kashtanov S. A. Makarov E. F. Chernyshev Yu. A. 《Kinetics and Catalysis》2001,42(2):233-237
The dependence of the rate of a photochemical reaction of XeO4with H2on the concentrations of H2and the diluent gases He and CO2is studied at room temperature. The results are compared with the data for the dark reaction. A mechanism with the elementary energetic branched-chain reaction OH
(v) + XeO4OH
+ O
+ XeO3is proposed to explain the results of the study. 相似文献
7.
8.
I. B. Rozentsveig Yu. A. Aizina K. A. Chernyshev L. V. Klyba E. R. Zhanchipova E. N. Sukhomazova L. B. Krivdin G. G. Levkovskaya 《Russian Journal of General Chemistry》2007,77(5):926-931
The mixtures of mono-and dihalothiophenesulfonyl chlorides, formed in the sulfochlorination reaction of 2,5-dichlorothiophene
and 2,5-dibromothiophene, were treated with aqueous ammonia and thus converted into mixtures of the corresponding stable thiophenesulfonamides.
The structure and composition of the latter were studied by physicochemical methods: GC-MS and 1H, 13C, 1H-13C HSQC, 1H-13C HMBC, and NOESY NMR spectroscopy. As a result of the above chemical transformations, 2,5-dichlorothiophene afforded a mixture
of 5-chlorothiophene-2-sulfonamide and 4,5-dichlorothiophene-3-sulfonamide in a roughly 70:30 ratio. In the case of 2,5-dibromothiophene,
a mixture of 5-bromothiophene-2-sulfonamide, 4,5-dibromothiophene-3-sulfonamide, and 3,5-dibromothiophene-2-sulfonamide (3:54:43)
was formed.
Original Russian Text I.B. Rozentsveig, Yu.A. Aizina, K.A. Chernyshev, L.V. Klyba, E.R. Zhanchipova, E.N. Sukhomazova, L.B.
Krivdin, G.G. Levkovskaya, 2007, published in Zhurnal Obshchei Khimii, 2007, Vol. 77, No. 5, pp. 831–836. 相似文献
9.
V. D. Sheludyakov Z. V. Belyakova V. M. Shevchenko E. A. Chernyshev 《Russian Chemical Bulletin》1997,46(5):997-1002
Novel dialkylaminocarbenium salts with metallocomplex counter ions were prepared by the reaction of phosgene with either DMF
or tetramethylurea in the presence of metal chlorides. Reactions of organosilicon amides with phosgene gave corresponding
carbenium salts, while organosilicon ureas yielded aminoiminocarbenium salts. Dialkylaminochlorocarbenium salts were reduced
with hydrosilanes to give dialkylaminocarbenium, salts and can be easily hydrolyzed to afford either amides or ureas. Pathways
of the reaction with water and alcohols depend on the nature of reagent and the reaction conditions.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1035–1040, May 1997. 相似文献
10.
E. A. Chernyshev T. L. Krasnova E. S. Abramova E. A. Abronin A. B. Petrunin A. P. Sergeev 《Russian Chemical Bulletin》1997,46(9):1582-1585
Pyrolysis of trichlorosilane (TCS) and copyrolysis of TCS with 1,3-butadiene were studied. The enthalpies and activation energies
for the reactions of the products of TCS pyrolysis were found by quantum-chemical calculations. A direct study of the pyrolysis
of TCS by mass spectrometry was carried out. Based on the thermochemical parameters found by quantum-chemical calculations
and on the results of GLC and mass spectrometry concerning the composition of the pyrolysis products, it was concluded that
the pyrolysis of TCS follows a scheme that includes formation of radicals and silylenes.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1659–1662, September, 1997. 相似文献