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991.
G. N. Dorofeenko Yu. P. Andreichikov É. A. Zvezdina V. A. Bren' G. E. Trukhan V. V. Derbenev A. N. Popova 《Chemistry of Heterocyclic Compounds》1974,10(10):1177-1181
The pyridinium ring as a substituent in aniline is an electron acceptor, the effect of which is comparable to the effect of NO2 and N(CH3)2 groups. Correlation of the reactivities with the basicities of the amino groups is not observed in the investigated reactions of N-(aminophenyl)pyridinium perchlorates with some electrophilic reagents, inasmuch as steric factors apparently play a greater role. 相似文献
992.
993.
E. I. Klabunovskii N. P. Sokolova A. A. Vedenyapin Yu. M. Talanov N. D. Zubareva V. P. Polyakova N. V. Gorina 《Russian Chemical Bulletin》1972,21(10):2306-2306
Conclusions Skeletal ruthenium catalyst, modified with D-(+)-tartaric acid, leads to the asymmetric hydrogenation of the carbonyl group in acetoacetic ester.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, p. 2361, October, 1972. 相似文献
994.
995.
Bilevich K. A. Bubnov N. N. Ioffe N. T. Kalinkin M. I. Okhlobystin O. Yu. Petrovskii P. V. 《Russian Chemical Bulletin》1971,20(8):1707-1708
Russian Chemical Bulletin - 相似文献
996.
3,4-Bis(hydroxymethyl)furan was electrolytically methoxylated during intense cooling. 4,5-Bis(hydroxymethyl)pyridazine was obtained by reaction of the methoxylation product — 2,5-dimethoxy-3,4-bis (hydroxymethyl)-2,5-dihydrofuran — with hydrazine hydrate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1306–1307, October, 1970. 相似文献
997.
Summary For the primary alkyl halides (R=from C2H5 to n-C9H19; halogen=C1, Br, and I) and the simplest aryl halides (R=C6H5 and p-CH3C6H4) it was shown that the organomagnesium synthesis in absence of catalysts for the Grignard reaction can be applied with success to the preparation of heteroorganic compounds of elements of Groups II–IV (mercury, boron, aluminum, silicon, germanium, tin, phosphorus, arsenic, antimony). 相似文献
998.
Shahkel'dyan I. V. Melekhina E. K. Atroshchenko Yu. M. Efremov Yu. A. Alifanova E. N. Kopyshev M. V. Troitskii N. A. Subbotin V. A. Nikishina M. B. 《Russian Journal of Organic Chemistry》2003,39(4):589-595
A series of 7-carboxy-3-R-1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes was synthesized by reduction of 3,5-dinitrobenzoic acid with sodium borohydride followed by Mannich reaction with formaldehyde and primary amines. The mechanism of decomposition under electron impact of the 3-azabicyclo[3.3.1]nonane was established. Enthalpies of formation of compounds synthesized were calculated by semiempirical PM3 method. 相似文献
999.
Chao Wang Jing Wang Xiang Xiao Guobin Zhong Shijia Wu Kaiqi Xu Wei Zhao Wei Su Jie Zeng Baojun Wu Weili Zhang Changcheng Wu Zhiqiang Shi 《中国化学快报》2019,30(6):1269-1272
A novel cyclic ammonium salt, N,N-dimethylpyrrolidinium tetrafluoroborate (P11-BF4), was successfully synthesized for the first time. The smallest cyclic structure of P11-BF4 induced high solubility and conductivity in PC, which can easier enter the micropores of activated carbon and occupy more surface area during charge/discharge process. 相似文献
1000.
Shul'ga Yu. M. Chernushevich I. V. Dzhardimalieva G. I. Roshchupkina O. S. Dodonov A. F. Pomogailo A. D. 《Russian Chemical Bulletin》1994,43(6):983-987
Russian Chemical Bulletin - The monomer [Cr3O(OCOCH=CH2)6]OH was produced by reaction of acrylic acid with fresh chromium hydroxide. This monomer was investigated by a number of physicochemical... 相似文献