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991.
V. A. Mamedov E. A. Khafizova T. N. Beschastnova N. A. Zhukova A. T. Gubaidullin I. Kh. Rizvanov E. A. Berdnikov I. A. Litvinov 《Russian Chemical Bulletin》2007,56(5):1088-1089
Three-component condensation of pyridin-2-one, bis(2-chloroethyl)amine hydrochloride, and K2CO3 in DMF unexpectedly gave N-and O-oxazolidinylethylation products of pyridin-2-one in the ratio 3: 2.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1047–1048, May, 2007. 相似文献
992.
V. P. Litvinov T. V. Shchedrinskaya P. A. Konstantinov Ya. L. Gol'dfarb 《Chemistry of Heterocyclic Compounds》1975,11(4):431-436
It is shown that the catalytic liquid-phase oxidation of 3-methylthieno[2,3-b]-thiophene and 3-methylthieno[3,2-b]thiophene in acetic acid in the presence of cobalt acetate and sodium bromide at 90–110° gives thieno[2,3-b]thiophene-3-carboxylic acid and thieno[3,2-b]-3-formylthiophene, respectively.See [1] for communication XXXII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 492–498, April, 1975. 相似文献
993.
I. V. Fedyunina V. V. Plemenkov G. Sh. Bikbulatova L. E. Nikitina I. A. Litvinov O. N. Kataeva 《Chemistry of Natural Compounds》1992,28(2):173-177
Addition reactions of cyclic amines (morpholine, piperidine) to oxides of 3-carene in the presence of water have been studied. The reactions take place regio- and stereoselectively with the formation of amino derivatives of the carane series.S. V. Kurashov Kazan' State Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 203–208, March–April, 1992. 相似文献
994.
V. I. Galkin Yu. V. Bakhtiyarova R. I. Sagdieva I. V. Galkina R. A. Cherkasov D. B. Krivolapov A. T. Gubaidullin I. A. Litvinov 《Russian Journal of General Chemistry》2006,76(3):430-436
Reactions of 3-(triphenylphosphonio)propanoate with heterocumulenes, such as phenyl isocyanate and dicyclohexylcarbodiimide, we studied under the assumption that they proceed by nucleophilic addition and 1,4-dipolar cycloaddition schemes. Quantum-chemical calculations show that the σ5-phosphorane cycloadduct of the betaine with isocyanate is thermodynamically preferred over its isomeric zwitter-ionic adduct. However, the experimental evidence suggests that the reaction with phenyl isocyanate involves nucleophilic addition of the betaine to isocyanate followed by hydrolysis to firm finally a complex of the starting betaine with diphenylurea. The structure of the complex was established by X-ray diffraction analysis. The revealed above controversy is explained by a high protophilicity of betaine structures, which is also confirmed by the results of the reaction of the betaine with carbodiimide. 相似文献
995.
S. V. Matrosova V. K. Zav'yalova V. P. Litvinov Yu. A. Sharanin 《Russian Chemical Bulletin》1991,40(7):1456-1459
The interaction of 2-thienylidene derivatives of malononitrile and cyanothio-acetamide with methylene active nitriles gives 2,6-diamino-3,5-dicyano-4-(2-thienyl)-4H-thiopyran which is smoothly recrystallized into 6-amino-3,5-dicyano-4-(2-thienyl)-2(1H)-pyridinethione. The latter is easily alkylated at the sulfur atom by -halocarbonyl compounds. This reaction was used in the synthesis of 3,6-diamino-4-(2-thienyl)thieno[2,3-b]pyridines.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1643–1646, July, 1991. 相似文献
996.
N. E. Dontsov V. N. Nesterov A. M. Shestopalov V. P. Litvinov 《Russian Chemical Bulletin》2005,54(5):1239-1244
The reactions of substituted pyridinium salts with E-1,2-di(alkylsulfonyl)-1,2-dichloroethenes proceed regiospecifically. Heating of these reagents in chloroform in the presence
of a threefold excess of Et3N affords substituted 1,2-di(alkylsulfonyl)indolizines in high yields. The structures of the reaction products were confirmed
by physicochemical methods, including X-ray diffraction.
Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1205–1209, May, 2005. 相似文献
997.
Victor V. Dotsenko Sergey G. Krivokolysko Alexander N. Chernega Victor P. Litvinov 《Monatshefte für Chemie / Chemical Monthly》2007,138(1):35-42
Summary. 3,5,7,11-Tetraazatricyclo[7.3.1.02,7]tridec-2-ene derivatives were prepared in one-pot manner from N-methylmorpholinium 6-amino-3,5-dicyano-4-spiro(1′-cycloalkane)-1,4-dihydropyridine-2-thiolates, primary amines, and formaldehyde
in 70–88% yields. The structure of 5,11-dibenzyl-13-spiro(1′-cyclopentane)-8-thioxo-3,5,7,11-tetraazatricyclo[7.3.1.02,7]tridec-2-ene-1,9-dicarbonitrile was determined by X-ray diffraction analysis. 相似文献
998.
A. A. Shestopalov L. A. Rodinovskaya A. M. Shestopalov V. P. Litvinov 《Russian Chemical Bulletin》2005,54(4):992-996
Three-component reactions of 4-hydroxycoumarin, carbonyl compounds, and malono-nitrile or alkyl cyanoacetates in ethanol in
the presence of Et3N as a catalyst give substituted 2-amino-5-oxo-4,5-dihydropyrano[3,2-c]chromenes.
Dedicated to Academician V. I. Minkin on the occasion of his 70th birthday.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 968–972, April, 2005. 相似文献
999.
B. I. Buzykin E. V. Mironova V. N. Nabiullin A. T. Gubaidullin I. A. Litvinov 《Russian Journal of General Chemistry》2006,76(9):1471-1486
The X-ray diffraction study of potentially tautomeric 3(5)-butylsulfanyl-5(3)-methyl-1H-1,2,4-triazole and its 5(3)-phenyl-substituted analog showed that these compounds in crystal have the structure of 3-butylsulfanyl-5-methyl(phenyl)-1H-tautomers. Analysis of our experimental and published data indicated that 3(5)-monosubstituted 1,2,4-triazoles and 3,5-disubstituted derivatives having nonequivalent substituents in crystal as exist as a tautomer in which the electron-acceptor substituent (RA) occupies the 3 position, while the electron-donor substituent (RD) resides in the 5 position, i.e., as 3-RA-5-RD-1H-1,2,4-triazoles. Symmetric 3,5-disubstituted 1,2,4-triazoles could give rise to tautomeric equilibrium between the 1H-and 2H-structures even in crystal. 相似文献
1000.
The structure of 4-hydroxy-4-[1-n-butyl-2-phenyl-2-(diphenylphosphino)ethenyl]-2-methyl-5,5-di-(n-butyl)-1-tert-butyl-1-aza-3-azonia-4-boratacyclopent-2-ene (I), the product of the reaction of the title compounds, has been established by X-ray structure analysis. The heterocycle has an envelope conformation, with the B atom deviating from the plane of four atoms. The distribution of bond lengths in the heterocycle is indicative of a delocalization in the N–C–N fragment. In the crystal, the molecules I form centrosymmetric dimers with the help of the H-bonds N–H...O. The hydroxyl group has a short intramolecular contact to the phosphorus atom, which can be interpreted as the hydrogen bond of the O–H...P type.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Scientific Center, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 34, No. 3, pp. 91–95, May–June 1993.Translated by T. Yudanova. 相似文献