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41.
Electrochemical perfluoroalkylation of the enol acetate of ethyl acetoacetate was studied in the conditions of the Kolbe reaction. The yields of alkylation products depend on the competing adsorption of the enol acetate, the solvent, and perfluorocarboxylates on the surface of a platinum electrode.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2948–2951, December, 1996.  相似文献   
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医药类专业物理课程教学存在的问题及对策   总被引:2,自引:0,他引:2  
根据对国内69所普通高等院校医药类专业(本科)物理课程教学现状调查的结果,分析了在我国高等教育进入“大众化教育”的形势下,医药类专业物理课程教学中存在的4个急需解决的问题,指出了医药类专业物理课程教学改革的方向,并介绍了我们所做的一些工作。  相似文献   
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S-Alkylation followed by heterocyclization of trifluoromethyl-3-cyano-2(1H)-pyridinethiones was used for preparation of libraries of S-alkyl trifluoromethylpyridines and thieno[2,3-b]pyridines. The S-alkylation (in water--DMF mixtures) was successful for all 18 alkylating agents employed (yields typically > 50%). S-Alkyl derivatives were further converted to corresponding thieno[2,3-b]pyridines via heterocyclization in base conditions (yields > 65%). Structures of new compounds were elucidated by a combination of IR and 1H NMR spectroscopy and elemental analysis and were confirmed by means of single-crystal X-ray diffraction analysis.  相似文献   
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Nitroheterocyclic compounds were reduced in a classical reactor with an agitator equipped with a cell for fixed bed of catalyst. As catalysts were applied granular palladium catalysts (0.5% of Pd on -Al2O3 and 2% of Pd on granulated carbon). Anilines and 3-amino-2(1H)-pyridones were obtained in high yield at reduction of the appropriate nitro compounds, and the activity of the catalyst samples only slightly decreased. Yet aminopyrazoles and aminoimidazoles obtained by hydrogenation on palladium were very sensitive to the presence of air even as hydrochlorides. In the course of hydrogenation of nitropyrazoles and nitroimidazoles the activity of the catalyst markedly decreased.  相似文献   
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The reaction of nitroacetamide with 1,3-dicarbonyl compounds afforded 3-nitropyrid-2(1H)-ones. The chemical reactivities of nitroacetamide and nitroacetohydrazide were compared.  相似文献   
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