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51.
2-Nitro-1,3-dicarbonyl and -nitromonocarbonyl compounds were synthesized in the yields varying from moderate (30 %) to nearly quantitative by the nitration of -dicarbonyl compounds in a two-phase system: sulfuric/nitric acid mixture-chloroform at - 10÷10 °C. The use of phase transfer conditions made it possible to avoid the formation of furoxans as by-products and to simplify the isolation of products. This method is quite common for preparing various -functional nitro compounds including those containing a CF3-group. Key words: nitration, -functional nitro compounds.Translated fromIzvestiya Akademn Nauk. Seriya Khimicheskaya, No. 1, pp. 76–79, January, 1994. 相似文献
52.
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54.
A. I. Syrchina N. N. Pechurina A. L. Vereshchagin A. G. Gorshkov I. É. Tsapalova A. A. Semenov 《Chemistry of Natural Compounds》1993,29(4):535-536
Irkutsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii,
No. 4, pp. 608–609, July–August, 1993. 相似文献
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Chevela V. V. Bezryadin S. G. Semenov V. E. Shamov G. A. Ivanova V. Yu. 《Russian Journal of Coordination Chemistry》2003,29(6):419-424
The geometric parameters of dl- and d-tetranuclear iron(III) tartrates [Fe4(d-L)2(l-L)2(H2O)8]4–and [Fe4(d-L)4(H2O)8]4–(H4L is tartaric acid) were optimized using the molecular mechanics method (MIND program, Dashevskii–Plyamovatyi model). 相似文献
57.
Compounds consisting of two or three uracil fragments were synthesized by reaction of methyl-substituted uracil sodium salts with 1-(6-bromohexyl)-3,6-dimethyluracil or 1,6-dibromohexane. Treatment of these compounds with paraformaldehyde gave the corresponding pyrimidinophanes and acyclic compounds in which the uracil fragments are linked through methylene bridges. Uracil derivatives having no substituent on N3 were synthesized by reactions of silylated uracils with 1,3-bis(6-bromohexyl)uracil or 4,4′-(6-bromohexyloxy)diphenylmethane. The acyclic compound was converted into pyrimidinophane containing uracil fragments with N3H groups. A trinucleotide analog including uracil and two adenine fragments was synthesized from 1,3-bis(6-bromohexyl)uracil. 相似文献
58.
V. V. Semenov A. B. Bruskin S. A. Shevelev A. A. Fainzil'berg 《Russian Chemical Bulletin》1982,31(12):2423-2427
Conclusions On interacting iodonium dinitromethylides with aromatic hydrocarbons of the benzene series the corresponding aryldinitromethanes were formed, i.e., the product of introducing the carbanion portion of the ylide at the C-H bond of the aromatic ring. The influence of temperature and added salts of transition metals on the yileld of reaction products has been clarified.Translated from Izvestiya Akademii Nauk SSSR, No. 12, pp. 2741–2746, December, 1982. 相似文献
59.
D. V. Tsyganov A. P. Yakubov L. D. Konyushkin S. I. Firgang V. V. Semenov 《Russian Chemical Bulletin》2007,56(12):2460-2465
A series of analogs of the natural mitostatic agent combretastatin were synthesized by the reaction of nitrile oxides with
natural allylbenzenes, such as myristicin, apiol, and dillapiol. The 1,3-dipolar cycloaddition reactions in allylic systems
proceed regiospecifically. The reactions with trans isomers of propenylbenzenes, viz., isomyristicin, isoapiol, and isodillapiol, as dipolarophiles produce regioisomers.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2375–2380, December, 2007. 相似文献
60.
Samet AV Niyazymbetov ME Semenov VV Laikhter AL Evans DH 《The Journal of organic chemistry》1996,61(25):8786-8791
Regioselective Michael addition of nitro and heterocyclic compounds to levoglucosenone, 1, is effectively catalyzed by amines and also by cathodic electrolysis. In comparison to the base-catalyzed reaction, it was found that under electrochemical conditions the reaction proceeds under milder conditions and with higher yields. Cathodically-initiated Michael addition of thiols to levoglucosenone using small currents produces the previously unknown threo addition product in several instances. The normal erythro isomer, identified as the kinetic product, tends to be formed when large currents are used. In contrast, slow, low current electrolyses promote equilibration of the two forms so that erythro can be converted to threo by the retro reaction and readdition. Addition of 2-naphthalenethiol to (R)-(+)-apoverbenone is also reported. 相似文献