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1.
Yu. V. Tomilov D. N. Platonov G. P. Okonnishnikova O. M. Nefedov 《Russian Chemical Bulletin》2010,59(7):1387-1392
Thermal decomposition of N-substituted hepta(methoxycarbonyl)-3a,7a-dihydroindazoles proceeds through the elimination of hexamethyl benzenehexacarboxylate
and results in the generation of l-aryl-3-methoxycarbonylnitrile imines, which are intercepted by both the electron-withdrawing
and electron-releasing olefins, for example, methyl acrylate, cyclopentene, vinylcyclopropane, or ethyl vinyl ether, to form
the corresponding pyrazolines and pyrazoles. In the presence of propan-2-ol, the main process proceeds through the addition
of nitrile inline to the O—H bond to form methyl 2-isopropoxy-2-[2-(4-methoxyphenyl)hydrazono]acetate. 相似文献
2.
Formation of N-cyclopropylhydrazones by azo coupling of cyclopropyldiazonium with aliphatic CH acids
Tomilov Yu. V. Kostyuchenko I. V. Shulishov E. V. Okonnishnikova G. P. 《Russian Chemical Bulletin》2003,52(4):993-997
Decomposition of N-cyclopropyl-N-nitrosourea under the action of K2CO3 or KOH containing 15—20% of H2O at 0—7 °C gives rise to cyclopropyldiazonium, which reacts with some -diketones, methyl cyanoacetate, or malonodinitrile to form the corresponding cyclopropylhydrazones. The latter compounds are analogous to products of azo coupling and isomerization of aryldiazonium ions with the above-mentioned substrates. These transformations provide the first example of azo coupling of the cyclopropyldiazonium ion in the series of activated aliphatic CH acids. 相似文献
3.
I. V. Kostyuchenko G. P. Okonnishnikova E. V. Shulishov Yu. V. Tomilov 《Russian Chemical Bulletin》2004,53(10):2257-2261
3-Cyano- and 3-(alkoxycarbonyl)spiro[2-pyrazoline-5,1’-cyclopropane] and 5-phenylspiro[1-pyrazoline-3,1’-cyclopropane] undergo unusual transformations into 3(5)-substituted 5(3)-(2-hydroperoxyethyl)pyrazoles in the presence of atmospheric oxygen. The conditions for the formation of hydroperoxides (e.g., in oxygen-saturated solutions of spiro[2-pyrazoline-5,1’-cyclopropanes] in CHCl3) and their conversion into (2-hydroxyethyl)pyrazoles or the corresponding nitrates under the action of nitrosating reagents were considered.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2160–2164, October, 2004. 相似文献
4.
Yu. V. Tomilov D. N. Platonov G. P. Okonnishnikova R. A. Novikov N. V. Volchkov 《Russian Chemical Bulletin》2012,61(6):1138-1147
Thermal decomposition of 1-(4-methoxyphenyl)- and 1-(4-fluorophenyl)hepta(methoxycarbonyl)-3a,7a-dihydroindazoles at 135 °C in the presence of allyl or propargyl halides leads to the elimination of hexamethyl benzenehexacarboxylate and the formation of the corresponding pyrazolines or pyrazoles as the products of 1,3-dipolar cycloaddition of 1-aryl-3-methoxycarbonylnitrilimines to the multiple bonds of the substrates used. In the case of vinyl halides, the products of the target reactions are either obtained in low yields or nonexistent, with a side conversions taking place instead. Thus, for example, in the case of 1,1-dichloro-4-methylpenta-1,3-diene, besides hexamethyl benzenehexacarboxylate, 3,5,5-trichloro-2-methylpent-4-en-2-ol and arylchlorohydrazones MeO2CC(Cl)=N-NHAr were unexpectedly isolated as the main products, as well. 相似文献
5.
Yu. V. Tomilov I. V. Kostyuchenko G. P. Okonnishnikova I. P. Klimenko E. V. Shulishov 《Russian Chemical Bulletin》2006,55(11):2008-2012
A new way of generating cyclopropyl radicals in the base-catalyzed decomposition of N-cyclopropyl-N-nitrosourea in the presence of organic reducing agents (1-phenylpyrazolidin-3-one and 4-methoxyphenol) was developed. The
cyclopropyl radical generated under these conditions can not only abstract a proton from the substrate to give cyclopropane
but also form C-C or C-Br bonds in reactions with aromatic substrates or polybromomethanes.
Dedicated to Academician O. M. Nefedov on the occasion of his 75th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1934–1938, November, 2006. 相似文献
6.
Tomilov Yu. V. Okonnishnikova G. P. Kostyuchenko I. V. 《Russian Chemical Bulletin》2003,52(4):1038-1039
Russian Chemical Bulletin - 相似文献
7.
8.
Yu. V. Tomilov G. P. Okonnishnikova E. V. Shulishov K. N. Shavrin O. M. Nefedov 《Russian Chemical Bulletin》1998,47(11):2208-2212
A THF solution of diazopropyne was obtained in 60% yield by the reaction of a 30% aqueous solution of methylamine withN,N′-dinitroso-N,N′-dipropargylterephthalodiamide. The reactions of diazopropyne with methyl acrylate and methyl methacrylate giving various
ethynylpyrazolines as well as its CuCl-catalyzed decomposition in the presence of norbornene or norbornadiene yielding ethynylcyclopropanes
were studied. The main products of catalytic deazotization of diazopropyne in the absence of unsaturated compounds are isomericE- andZ-hex-3-ene-1,5-diynes resulting from propargylene dimerization.
For Part 12, see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2278–2282, November, 1998. 相似文献
9.
D. N. Platonov G. P. Okonnishnikova R. F. Salikov Yu. V. Tomilov 《Russian Chemical Bulletin》2009,58(11):2283-2287
Hydrogenation of heptamethyl cycloheptatrieneheptacarboxylate in the presence of palladium/carbon affords a stereoisomer of
heptamethyl cyclohepteneheptacarboxylate with the cis-position of five ester groups in a yield of 60%, as well as the corresponding cyclohepta-1,3-dienes as trans,trans- and trans,cis-isomers. The reaction with sodium borohydride results in the stereoselective formation of bicyclic compound 5 upon reduction of one double bond and intramolecular cyclization. X-ray diffraction analysis of the compounds formed is carried
out. 相似文献
10.
Yu. V. Tomilov I. V. Kostyuchenko G. P. Okonnishnikova E. V. Shulishov E. A. Yagodkin O. M. Nefedov 《Russian Chemical Bulletin》2000,49(3):472-477
Hydrochlorination of spiro(1-pyrazoline-3,1′-cyclopropanes) proceeds regioselectively at the azocyclopropane group to form 3-(2-haloethyl)pyrazoline derivatives. If the latter contain a halogen atom in the heterocycle, they are readily converted into (2-haloethyl)pyrazole hydrohalides. Bromination of 3-cyanospiro(2-pyrazoline-5,1′-cyclopropane) withN-bromosuccinimide at 20°C proceeds with retention of the cyclopropane ring to form 3-bromo-3-cyanospiro(1-pyrazoline-5,1′-cyclopropane), which is converted into (2-bromoethyl)cyanopyrazole in ∼60% yield at ∼20°C after 3–4 days. 相似文献