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91.
R. A. Gavar L. Kh. Baumane Ya. P. Stradyn' S. A. Giller 《Chemistry of Heterocyclic Compounds》1974,10(3):280-284
Anion radicals of 2-vinylene derivatives of 5-nitrofuran were obtained by electrochemical generation. The hyperfine structure (hfs) of the ESR spectra of these anion radicals indicates delocalization of the unpaired electron over their entire π-electron system. The effect of the vinylene grouping on the distribution of the unpaired electron in the anion radicals and on the distribution of the unpaired electron in the vinylene grouping itself was examined on the basis of the hfs constants. It was found that the vinylene grouping by localizing more than 10% of the density of the unpaired electron on itself reduces, by a factor of 1.4, the effect of substituents in the 2 position of 5-nitrofuran on the distribution of the spin of the unpaired electron in the nitrofuran framework. 相似文献
92.
93.
U. G. Magomedbekov Kh. M. Gasanova U. G. Gasangadzhieva K. A. Abdulkhamidov S. Sh. Mutsalova 《Moscow University Chemistry Bulletin》2007,62(4):230-236
A possible mechanism of 1,4-naphthalenediol oxidation in the oscillatory regime has been considered, and a mathematical model describing the kinetics has been developed. Based on a thermodynamic Lyapunov function, it has been shown that the source of chemical instabilities is in the existence of autocatalytic steps and dynamic feedbacks. Qualitative analysis and numerical solution of the set of differential equations that model the reaction kinetics have been performed. The character of the stationary state and the possibility of bifurcations have been determined. The mathematical model satisfactorily describes the processes occurring in the system. 相似文献
94.
95.
96.
O. E. Nasakin A. N. Lyshchikov P. M. Lukin A. Kh. Bulai 《Chemistry of Heterocyclic Compounds》1995,31(1):35-39
It was shown that briefly boiling solutions of 2,5-diaryl-3,3,4,4-tetracyanopyrrolidines in DMF caused rearrangement into 5-aryl-2-(N-arylidenamino)-3,4-dicyanopyrroles, which are methylated with diazomethane both at the NH bond and at the carbon atom of the azomethine fragment.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 42–46, January, 1995. 相似文献
97.
N. S. Prostakov B. Kh. Sisimbina S. A. Soldatova V. P. Shalimov K. G. Montenegro N. I. Leonova L. A. Murugova 《Chemistry of Heterocyclic Compounds》1982,18(12):1290-1294
Isomeric (with respect to the position of the nitrogen atom) azafluorenes were cyanoethylated. The resulting 9,9-bis(-cyanoethyl) derivatives were converted to the corresponding dibasic acids and their diesters. The latter were subjected to the Dieckmann reaction to obtain spiro compounds with azafluorene and cyclohexene fragments. The analogous spirans with 1,3-dioxalane and 1,3-dioxane rings were obtained from 3-methyl-2-azafluorenone.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1668–1672, December, 1982. 相似文献
98.
99.
100.
G. S. Lyashenko A. Kh. Filippova I. D. Kalikhman G. G. Naumova N. S. Vyazankin 《Russian Chemical Bulletin》1982,31(11):2312-2314
Conclusions The addition of Et3GeH to the phenoxy- and phenylthioacetylenes under the influence of (Ph3P)3RhCl is both nonstereo- and nonregiospecific. The analogous reaction with 3-aroxy-1-propynes is stereospecific but nonregioselective.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2618–2620, November, 1982. 相似文献