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V.V. Nosyreva A.G. Mal'kina O.A. Shemyakina E.I. Kositsyna A.I. Albanov B.A. Trofimov 《Russian Journal of Organic Chemistry》2005,41(8):1202-1207
Nucleophilic addition of tetrazole to 4-hydroxy-4-alkyl-2-alkynonitriles and to 3-phenyl-2-propynonitrile occurred regiospecifically and afforded E-, Z-4-hydroxy-4-methyl-3-tetrazolyl-2-alkenonitriles and 3-tetrazolyl-3-phenyl-2-propenonitrile [20–40°C, 13–50 h, 4–15 wt% MOH (M = Na, K), THF (or DMSO)] in up to 69% yield. The attempt to perform cyclization of the hydroxy-containing adducts into iminodihydrofurans (KOH, ethanol, 23-25°C) resulted in vinyl nucleophilic substitution of the tetrazole moiety by an ethoxy group. 相似文献
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G. F. Prozorova I. V. Mazyar V. V. Nosyreva S. A. Korzhova T. I. Vakul’skaya B. A. Trofimov 《Russian Journal of General Chemistry》2014,84(5):892-900
Interaction of trichloroethene with sodium tetra- and pentasulfide (prepared in turn from sodium sulfide and elemental sulfur) has lead to new family of polyvinylenepolysulfides containing up to 94% of sulfur. The polymers were found highly electrochemically active when applied as active cathode for lithium batteries. 相似文献
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B. A. Trofimov V. V. Nosyreva A. G. Mal'kina 《Russian Journal of Organic Chemistry》2005,41(9):1254-1259
Macrocyclic polyether dibenzo-18-crown-6 possessing a specific affinity for potassium cation inhibits ethynylation of acetone with acetylene in the presence of KOH according to Favorskii. The inhibition becomes stronger in the presence of the complex dibenzo-18-crown-6 ? KOH ? MeOH as catalyst (both in excess acetone and in DMSO). The effect does not originate from deactivation of acetone, for its aldol-like condensation is accelerated in the presence of both dibenzo-18-crown-6 and its complex (the selectivity of ethynylation sharply falls down). Thus, apart from the high basicity of the medium, activation of acetylene due to complex formation with potassium cation plays an important role in the Favorskii ethynylation of ketones. 相似文献
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V. V. Nosyreva L. V. Andriyankova A. G. Mal''kina A. V. Afonin B. A. Trofimov 《Russian Journal of Organic Chemistry》2001,37(6):859-865
Nucleophilic addition of 2-mercaptobenzothiazole to 4-alkyl-4-hydroxy-2-alkynonitriles at 1:1 ratio in the presence of 4-6 wt% of Et3N occurs regio- and stereospecifically to afford (Z)-4-alkyl-3-(benzothiazolyl-2-thio)-4-hydroxy-2-alkenonitriles (yield 40-51%). In the presence of 1.3 wt% of Dabco the thiazole and 4-hydroxy-4-methyl-2-pentynonitrile (1:1) give rise to a mixture of 2-alkenonitrile and 2-(3,3,6,6-tetramethyl-2-cyanomethyl-5-cyanomethylene-1,4-oxathian-2-yl)thiobenzothiazole. At the use of 4-6 wt% of LiOH arises an intractable mixture containing 1,4-oxathiane, benzothiazol-2-one, 2-[1-(5,5-dimethyl-2-cyanomethyl)-4-cyanomethylene-1,3-oxathiolan-2-yl)-1-methylethyl]thiobenzothiazole, bis(2,2,5,5-tetramethyl-6-cyanomethyl-3-cyanomethylene-1,4-oxathian-6-yl) disulfide, bis[1-(5,5-dimethyl-2-cyanomethyl-4-cyanomethylene-1,3-oxathiolan-2-yl)-1-methylethyl] disulfide, and 3-[1-(5,5-dimethyl-2-cyanomethyl-4-cyanomethylene-1,3-oxathiolan-2-yl)-1-methylethyl]benzothiazol-2-one (according to 1H and 13C NMR data). 2-mercaptobenzothiazole adds to 3-phenyl-2-propynonitrile in the presence of 7 wt% of KOH with regio- and stereospecific formation of (Z)-3-(benzothiazolyl-2-thio)-3-phenyl-2-propenonitrile (88%). 相似文献
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Influence of temperature and pressure on the effective diffusion coefficient in fine-pored catalysts
O. L. Vlasova K. G. Ione G. N. Nosyreva V. S. Levchuk V. N. Muratova 《Russian Chemical Bulletin》1972,21(11):2356-2360
Conclusions For the investigated substances at low degrees of surface coverage and temperatures below 150°, a substantial fraction of the mass transport is comprised of the flux along the surface; at high temperatures (>150°), the basic type of transport is diffusion in the gas phase.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2419–2424, November, 1972. 相似文献
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A. G. Mal’kina V. V. Nosyreva O. A. Shemyakina A. P. Borisova A. I. Albanov A. A. Tatarinova B. A. Trofimov 《Russian Chemical Bulletin》2013,62(11):2538-2543
l-Histidine chemo- and regioselectively reacts with tertiary cyanopropargylic alcohols (4,4-di-alkyl-4-hydroxybut-2-ynenitriles) under mild conditions (water, 6.4 wt.% NaOH, 5—15 °C, 72—175 h) with the formation of new “unnatural” amino acids containing an iminodihydrofuran substituent in the amino group (50—70% yields). 相似文献
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S. S. Khutsishvili L. B. Krivdin O. A. Shemyakina V. V. Nosyreva A. G. Mal’kina B. A. Trofimov 《Russian Journal of Organic Chemistry》2008,44(3):388-396
The configurations and conformations of twelve 5-imino-2,5-dihydrofuran-3-carboxamides and 5-imino-2,5-dihydrofuran-3-amines were determined by analysis of the experimental 13C-13C coupling constants and those calculated by nonempirical methods, as well as by quantum-chemical calculations of the total energies and optimization of geometric parameters of preferential conformations at the MP2/6-311G** level. All the examined compounds were found to be formed and to exist in solution as individual Z isomers with orthogonal orientation of the amino and dialkylamino groups and s-trans orientation of the carbamoyl group in the ring with restricted internal rotation about the C(O)-N bond. 相似文献