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31.
V. V. Semenov V. S. Bogdanov B. S. Él'yanov L. G. Mel'nikova S. A. Shevelev V. M. Zhulin A. A. Fainzil'berg 《Chemistry of Heterocyclic Compounds》1982,18(8):859-864
The quaternization of 1- and 2-acetonyl-5-R-tetrazoles, as well as dimethyltetrazole, was accomplished under high pressure conditions (5000–14,000 kgf/cm2) by means of bromoacetone and methyl iodide and at atmospheric pressure and room temperature under the influence of methyl fluorosulfate. The structure of the salts were ascertained by 13C NMR spectroscopy, and the principles of the change in the chemical shifts and the spin-spin coupling constants during quaternization and protonation of the tetrazoles were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1118–1124, August, 1982. 相似文献
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S. V. Lindeman Yu. T. Struchkov M. N. Élinson S. K. Fedukovich G. I. Nikishin 《Journal of Structural Chemistry》1989,30(3):512-514
A. N. Nesmeyanov Institute of Heteroorganic Compounds, Academy of Sciences of the USSR. N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 30, No. 3, pp. 171–173, May–June, 1989. 相似文献
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Conclusions Both the extent of C2H4 hydropolymerization, initiated by 0.01% CO, on Co zeolites at a temperature below 100°C, and the initiating effect increase symbatically with increase in the ratio of SiO2/Al2O3 in the zeolite in the investigated limits (from 2 to 10).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 894–896, April, 1974. 相似文献
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S. V. Baires D. É Vallen K. M. Enikeev A. S. Khramov V. E. Bel'skii A. V. Il'yasov B. E. Ivanov 《Russian Chemical Bulletin》1992,41(10):1801-1804
The interaction of synthetic analogs of active centers of iron-sulfur proteins with phosphates of different structures was studied. It was shown that the process involves ligand exchange and obeys the first-order reaction kinetic equation. The most rapid exchange occurred with the most acidic compound diphenyl phosphate.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center, Russian Academy of Sciences, 420083 Kazan'. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2301–2305, October, 1992. 相似文献
39.
A. A. Ladatko I. D. Sadekov L. N. Étmetchenko V. I. Minkin 《Chemistry of Heterocyclic Compounds》1989,25(5):577-580
10-Telluroniaanthracene perchlorates react with nucleophiles (X–=halide, hydroxide, methoxide) via intermediate free telluroxanthyl radicals. With 9-aryl-10-telluroniaanthracene perchlorates, high yields of 9-aryl-9-X-telluroxanthenes are obtained, but with 10-telluroniaanthracene the principal product is 9,9-bis(telluroxathenyl) as a result of rapid competitive dimerization.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 691–695, May, 1989. 相似文献
40.
R. G. Mirzoyan S. M. Saakyan P. B. Terent'ev K. A. Éliazyan V. V. Dovlatyan 《Chemistry of Heterocyclic Compounds》1982,18(9):983-985
Intense [M-Cl]+ and [M-CT2=CCNCl]+ ion peaks are characteristic for the mass spectra of 4-(-chloro--cyanoethylmercapto)-sym-triazines. The introduction of monoalkylamino groups into the 2 and 6 positions of the heteroring does not lead to the development of [M-HCl]+ ion peaks in the mass spectra or to a change in the characteristic fragmentation pathways.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1268–1270, September, 1982. 相似文献