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41.
42.
V. V. Dotsenko S. G. Krivokolysko A. N. Chernega V. P. Litvinov 《Russian Chemical Bulletin》2007,56(7):1431-1436
A new stereoselective method for the synthesis of trans-isomers of 2-amino-4-aryl-5-benzoyl-4,5-dihydrothiophene-3-carbonitriles was proposed. The method involves base-catalyzed
reactions of phenacyl thiocyanate with 3-(het)aryl-2-cyanoprop-2-enethioamides. (4R,5S/4S,5R)-2-Amino-5-benzoyl-4-(2-chlorophenyl)-4,5-ihydrothiophene-3-carbonitrile was structurally characterized by X-ray diffraction
analysis.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1379–1383, July, 2007. 相似文献
43.
44.
S. V. Bukharov I. A. Litvinov A. T. Gubaidullin A. V. Chernova R. R. Shagidullin G. N. Nugumanova N. A. Mukmeneva 《Russian Journal of General Chemistry》2004,74(11):1734-1740
The molecular and crystal structure and the hydrogen bonding in crystal and in solutions of N-phenyl-N-(3,5-di-tert-butyl-4-hydroxybenzyl)thiourea and N-(3,5-di-tert-butyl-4- hydroxybenzyl)thiourea were studied by single crystal X-ray diffraction and IR spectroscopy. The intermolecular interactions of these compounds are essentially different.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1864–1870.Original Russian Text Copyright © 2004 by Bukharov, Litvinov, Gubaidullin, Chernova, Shagidullin, Nugumanova, Mukmeneva.This revised version was published online in April 2005 with a corrected cover date. 相似文献
45.
V. A. Mamedov A. A. Kalinin V. V. Yanilkin N. V. Nastapova V. I. Morozov A. A. Balandina A. T. Gubaidullin O. G. Isaikina A. V. Chernova Sh. K. Latypov I. A. Litvinov 《Russian Chemical Bulletin》2007,56(10):2060-2073
The oxidative dehydrocyclization of the 3-(indolizin-2′-yl)-2-oxoquinoxaline monopodand performed either electrochemically
or under the action of molecular iodine affords new redox-active heterocyclophane consisting of the redox-switchable biindolizine
fragment combined with the polyether-bridged π-deficient quinoxaline systems. The single-crystal X-ray diffraction study showed
that the trioxaundecane chain of heterocyclophane adopts an extended conformation, and one of the phenyl substituents of the
molecule closes the pseudocavity formed by the spacer from one of the sides. The cyclic voltammetric study of heterocyclophane
in MeCN and DMF showed the three-step oxidation of the indolizine fragments accompanied by the single-electron transfer in
each step. The first and third steps are reversible, and the second step is irreversible. The oxidation at potentials of the
first peak gives rise to stable radical cations detected by the ESR method (g = 2.0024, a
2N = 0.26 mT).
Dedicated to Professor E. A. Berdnikov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1991–2003, October, 2007. 相似文献
46.
A. M. Shestopalov A. S. Demerkov Yu. A. Sharanin V. P. Litvinov 《Chemistry of Heterocyclic Compounds》1991,27(8):867-871
4-Amino-6-aryl-2,2-dialkyl-5-cyano-1,3-dithia-4-cyclohexenes react with pyridinium ylides in thermodynamically controlled conditions with the formation of 4-aryl-2-oxo-thioxo)-3-(1-pyridino)-5-cyano-3,4-trans-1,2,3,4-tetrahydropyridine-6-thiolates. Arylidenecyanothioacetamides act as intermediates of this recyclization, and the corresponding pyridine-6-thiolates were obtained from them by an independent method. The synthesized hydrogenated pyridine-6-thiolates are in the half-chair conformation with a trans-diaxial position of the 3-H and 4-H hydrogen atoms.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1082–1086, August, 1991. 相似文献
47.
V. A. Mamedov E. A. Berdnikov I. A. Litvinov L. G. Kuz'mina 《Russian Chemical Bulletin》1995,44(7):1247-1251
3,3-Dichloropentane-2,4-dione reacts with aromatic aldehydes under the conditions of Darzens reaction to give 4-acetoxy-4-aryl-3,3-dichlorobutan-2-ones, the products of insertion into the -C-C bond. The reaction of ethyl dichloroacetylacetate with benzaldehyde yields a derivative of tricyclo[5.1.0.03,5]octane, rather than 2,6-bis(1-chlorobenzylidene)cyclohexane-1,4-dione, as the by-product.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1294–1298, July, 1995. 相似文献
48.
F. N. Guseinov R. N. Burangulova E. F. Mukhamedzyanova B. P. Strunin O. G. Sinyashin I. A. Litvinov A. T. Gubaidullin 《Chemistry of Heterocyclic Compounds》2006,42(7):943-947
Heterocyclization of 2-chloroepoxy-1,1-diethoxy-2.3-butane with 2-amino-4-methylpyridine occurred with participation of all
three potential electrophilic centers to give 3,7-dimethyl-2-[N-(4-methylpyridyl-2)-4-hydroxy-3-methyl-5-oxopyrrolen-3-yl]imidazo[1,2-a]pyridine,
the structure of which was determined by X-ray crystallography.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, 1089–1094, July 2006. 相似文献
49.
A. S. Romakhin F. M. Palyutin Yu. A. Ignat'ev E. V. Nikitin Yu. M. Kargin I. A. Litvinov V. A. Naumov 《Russian Chemical Bulletin》1990,39(3):585-589
The electrochemical oxidation of hexaethyl triamidophosphite in the absence of nucleophiles specially introduced into the electrolyte was studied by anodic voltamperometry and preparative electrolysis. The reversible one-electron oxidation of the triamidophosphite molecule gives an unstable radical-cation, which reacts with a molecule of the starting compound to give a dimeric radical-cation, whose subsequent oxidation leads to dodecaethylhexaamidobisphosphonium diperchlorate. This product is the first example of an acyclic, doubly charged bisphosphonium cation with a
. The crystal structure of this compound was obtained by x-ray diffraction structure analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 664–669, March, 1990. 相似文献
50.
N-Methylmorpholinium 4-aryl-5-cyano-2-oxo-2-oxo-1,2,3,4-tetrahydropyridine-6-thiolates were obtained by the condensation of
aromatic aldehydes, cyanothioacetamide, and Meldrum's acid in the presence ofN-methylmorpholine. They were then used in the syntheses of substituted 6-alkylthio-3,4-dihydropyridin-2(1H)-ones and 4,5-dihydrothieno[2,3-b]pyridin-6(7H)-ones.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1852–1856, October, 1997. 相似文献