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61.
A. V. Lesiv S. L. Ioffe Yu. A. Strelenko V. M. Danilenko 《Russian Chemical Bulletin》2004,53(10):2233-2240
Coupling of N,N-bis(silyloxy)enamines with tertiary amines and nitrogen-containing heterocycles affording the corresponding functionalized ammonium or iminium salts was studied. The area of its application was determined, and optimal procedures for the synthesis of the target products were proposed. The mechanism including the formation of conjugated nitroso alkene or a silylnitrosonium cation as key intermediates is discussed.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2137–2143, October, 2004. 相似文献
62.
Ignat'eva DV Goryunkov AA Tamm NB Ioffe IN Avdoshenko SM Sidorov LN Dimitrov A Kemnitz E Troyanov SI 《Chemical communications (Cambridge, England)》2006,(16):1778-1780
Two isomers of C70(CF3)12 have been isolated from a mixture obtained by trifluoromethylation of C70 with CF3I; their molecular structures determined by X-ray crystallography are in good agreement with the results of theoretical DFT calculations for the most stable C70(CF3)12 isomers. 相似文献
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Dmitry L. Lipilin Oleg Yu. Smirnov Aleksandr M. Churakov Yuri A. Strelenko Sema L. Ioffe Vladimir A. Tartakovsky 《European journal of organic chemistry》2002,2002(20):3435-3446
The synthesis of 1,2,3,4-benzotetrazine 1-oxides (BTOs) is described. Bromo-BTOs 4b−d were prepared by the intramolecular cyclization of diazonium salts bearing an ortho-(tert-butyl)-NNO-azoxy group. BTOs bearing electron-releasing substituents were obtained by nucleophilic displacements of bromine in 4b−d . The formation of the BTO cyclic system involves the intermediate 2-(tert-butyl)-1,2,3,4-benzotetrazinium 4-oxides, which arise from an N,N-[1,2]-shift of the tert-butyl group. Decomposition of BTOs involves opening of the tetrazine ring to afford ortho-azidonitroso derivatives, followed by their cyclization with the evolution of the N2 molecule to give benzofurazans. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002) 相似文献
65.
Dmitry L. Lipilin Pavel A. Belyakov Yuri A. Strelenko Aleksandr M. Churakov Oleg Yu. Smirnov Sema L. Ioffe Vladimir A. Tartakovsky 《European journal of organic chemistry》2002,2002(22):3821-3826
The diazotization of anilines bearing the ortho-alkylazo group resulted in benzenediazonium salts 3 , which exist in equilibrium with the 2-alkyl-1,2,3,4-benzotetrazinium salt cyclic isomers 4 . The structures of 3 and 4 were confirmed by 1H, 13C, and 15N NMR studies. The relative proportions of the cyclic and open-chain forms were determined by a 1H NMR study. The 3 ⇄ 4 equilibrium is fast on the NMR timescale, and only one set of signals is observed in the 1H and 13C NMR spectra. The equilibrium strongly depends on the substituents on the aromatic ring, while being practically unaffected by the substituents (methyl or tert-butyl) on the azo group. Some of the investigated salts exist only in the cyclic form ( 4f , 4g ), others only in the open-chain form ( 3k ). (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002) 相似文献
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It has been shown by IR spectroscopy that the equatorial oxygen atoms of cholestanol and its methyl ether possess a greater capacity for forming H bonds as proton acceptors than the axial atoms of the corresponding epimeric compounds. The constants of the equilibrium phenol + ether H-complex (1:1) in CCl4 at room temperature are 13 and 7 liter/mole, respectively, for the methyl esters of cholestanol and of epicholestanol.Institute of Experimental Medicine, Academy of Medical Sciences of the USSR, Leningrad. Leningrad Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 703–708, November–December, 1986. 相似文献
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