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21.
Keremov A. F. Nemeryuk M. P. Aparnikova O. L. Safonova T. S. 《Chemistry of Heterocyclic Compounds》1977,13(10):1065-1068
Pyrimido[4,5-b]-1,4-thiazin-6-one and pyrimido[4,5-b]-1,5-thiazepin-6-one derivatives were obtained by reaction of 5-amino-6-chloropyrimidines with thioglycolic acid and 5-amino-6-mercaptopyrimidines with -bromopropionyl chloride. The IR spectra of the compounds are presented.See [1] for communication XXXV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1332–1335, October, 1977. 相似文献
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23.
Matthew P. Conley Murielle F. Delley Georges Siddiqi Giuseppe Lapadula Sébastien Norsic Vincent Monteil Olga V. Safonova Christophe Copéret 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(7):1903-1907
The insertion of an olefin into a preformed metal–carbon bond is a common mechanism for transition‐metal‐catalyzed olefin polymerization. However, in one important industrial catalyst, the Phillips catalyst, a metal–carbon bond is not present in the precatalyst. The Phillips catalyst, CrO3 dispersed on silica, polymerizes ethylene without an activator. Despite 60 years of intensive research, the active sites and the way the first Cr C bond is formed remain unknown. We synthesized well‐defined dinuclear CrII and CrIII sites on silica. Whereas the CrII material was a poor polymerization catalyst, the CrIII material was active. Poisoning studies showed that about 65 % of the CrIII sites were active, a far higher proportion than typically observed for the Phillips catalyst. Examination of the spent catalyst and isotope labeling experiments showed the formation of a Si–(μ‐OH)–CrIII species, consistent with an initiation mechanism involving the heterolytic activation of ethylene at CrIII O bonds. 相似文献
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25.
Yu. I. Savin A. S. Singin N. V. Sazonov A. A. Kropacheva T. S. Safonova 《Chemistry of Heterocyclic Compounds》1973,9(9):1135-1137
Pyrimidin-2-ylaminophosphonic di(ethyleneamide) labeled at the phosphorus atom (fosfemid-32P) has been synthesized both in an anhydrous medium and also using an aqueous alkaline solution of ethyleneimine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1251–1253, September, 1973. 相似文献
26.
27.
A. U. Makhkamova É. V. Safonova A. Z. Sadikov E. K. Dobronravova T. T. Shakirov 《Chemistry of Natural Compounds》1989,25(3):380-381
Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 436–438, May–June, 1989. 相似文献
28.
O. A. Burova I. D. Bystryakova N. M. Smirnova T. S. Safonova 《Chemistry of Heterocyclic Compounds》1990,26(5):561-564
1,3-Dimethyl-2,4,5-trioxo-7-amino-8H-pyrido[2,3-d]pyrimidine has been brominated, chlorosulfonated, treated with potassium nitrite in acidic medium, and with the Vilsmeier reagent. Acylation and alkylation of 1,3-dimethyl-2,4,5-trioxo-6-bromo-7-aminopyrido[2,3-d]pyrimidine is also discussed.For Communication 1, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 662–666, May, 1990. 相似文献
29.
A. G. Martynov E. A. Safonova Yu. G. Gorbunova A. Yu. Tsivadze 《Russian Journal of Inorganic Chemistry》2010,55(3):347-354
Two series of heteroleptic crown-substituted tris(phthalocyaninate) complexes (Pc)Ln[(15C5)4Pc]Ln(Pc) and [(15C5)4Pc]Ln[(15C5)4Pc]Ln(Pc), where 15C5 is 15-crown-5, (Pc2−) is the phthalocyaninate dianion, Ln = Nd, Eu, Ho, Er, and Yb, were prepared by the reaction of tetra-15-crown-5-phthalocyanine
H2[(15C5)4Pc] with the corresponding lanthanide acetylacetonates and lanthanum bis(phthalocyaninate) La(Pc)2, which was used as a phthalocyaninate dianion donor. The composition and structure of the synthesized complexes were confirmed
by MALDI TOF mass spectrometry, UV-Vis absorption spectroscopy, and 1H NMR. Complete assignment of the proton resonance signals of the paramagnetic lanthanide complexes was based on analysis
of lanthanide-induced shifts. 相似文献