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991.
V. D. Pokhodenko V. A. Krylov Ya. I. Kurys' 《Theoretical and Experimental Chemistry》1996,31(6):301-304
We propose a new approach to obtaining composites of the intercalation type based on polyaniline and V2O5. We have determined the characteristics of these composites using x-ray diffraction, IR spectroscopy, and EPR. We show that the compounds obtained exhibit stable redox properties in aqueous and aprotic electrolytes.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 31, No. 6, pp. 361–364, November–December, 1995.We would like to express our thanks to V. G. II'in for help in carrying out the x-ray phase investigations. This work was made possible with the partial support of the International Science Foundation (grant N U6B000). 相似文献
992.
993.
994.
995.
V. N. Voshula Yu. B. Vysotskii V. I. Seraya N. T. Novikova R. Ya. Mushii V. I. Dulenko 《Chemistry of Heterocyclic Compounds》1990,26(12):1349-1357
The interaction of 1-methallylpyrazoles with acetic or propionic anhydride in the presence of perchloric acid forms products of acylation at the double bond and subsequent heterocyclization — pyrazolo[1,2-a]pyridazinium salts — that are representatives of a new heteroaromatic system. Analogous cyclization is observed in the acylation of 3-(2-hydroxy-2-methylpropyl-pyrazole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1623–1631, December, 1990. 相似文献
996.
A. S. Balueva Yu. Ya. Efremov V. M. Nekhoroshkov O. A. Erastov 《Russian Chemical Bulletin》1989,38(12):2557-2560
1-Butyl-1-dibutylboryl-2-diphenylphosphino-2-phenylethene, which exists in the form 1,1,2-tributyl-3,4,4-triphenyT-1-borata-4-phosphoniacyclobut-2-ene, reacts with sulfur, selenium, methyl iodide, and pyridine under mild conditions with ring cleavage. In (2-butyl-2-dibutylboryl-1-phenylethenyl) diphenylphosphine sulfide and selenide, there is a coordinate bond between the thio-or selenophosphoryl group and the boron atom.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2793–2796, December, 1989. 相似文献
997.
V. A. Lopyrev L. I. Larina L. Kh. Baumane E. F. Shibanova R. A. Gavar S. M. Ponomareva T. I. Vakul'skaya Ya. P. Stradyn' 《Chemistry of Heterocyclic Compounds》1984,20(9):1021-1026
The electrochemical reduction of 2-substituted 5(6)-benzimidazoles has been studied with the aid of classical polarography and cyclic voltammetry in acetonitrile. The influence of the substituents in position 2 on the magnitudes of the half-wave potentials of the first stage is exerted by induction and resonance mechanisms with approximately the same contributions, and that on the magnitudes of the half-wave potentials of the second stage predominantly by the resonance mechanism. The possibilities of taking the radical-stabilizing factor into account in the correlations are discussed. In order to study the 2-substituted 5(6)-nitrobenzimidazole series, their pK
a
values in acetonitrile have been determined by potentiometric titration.For communication 3, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1246–1251, September, 1984. 相似文献
998.
999.
I. A. Litvinov O. N. Kataeva D. R. Sharafutdinova B. Ya. Teitel'baum 《Russian Chemical Bulletin》1988,37(2):262-264
Conclusions The geometric parameters of the molecules of the main cyclic-fraction component contained in a polysulfide oligomer synthesized from 2,2-dichlorodiethylformal were determined. The cyclic structure assigned to this compound according to mass spectrometric data was confirmed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 338–340, February, 1988.The authors thank A. Kh. Plyamovatyi for-useful discussion of the present paper. 相似文献
1000.
E. D. Skakovskii S. V. Rykov L. Yu. Tychinskaya Ya. N. Malkin 《Russian Chemical Bulletin》1987,36(8):1753-1755
Conclusions Negative polarization of the protons of aniline and other compounds is observed upon the photoexcitation of aniline solutions. This effect is a consequence of optical nuclear polarization in short-lived donor-acceptor complexes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1890–1892, August, 1987. 相似文献