Study On Ring - Forming Reaction Of Thioamide And Its New Synthesis Method

Thioamide is a very important class of organic sulfur compounds. Its easy synthesis, easy purification, no peculiar smell, and high stability; due to the sulfur atom electronegativity, extranuclear distribution characteristics make the nature of these compounds than the corresponding amide and lively, with a colorful range of chemical properties can be conversion reaction, causing its great attention, especially in the study of the biological activity of a compound. In recent years, the study results indicate that the biological activity of thioamide compounds is widely used, can be used for anti-inflammatory, antiseptic and anti-TB, but also as a class of compounds of special reagents or intermediates。The first part N-allylbenzothioamide and ferric chloride as the research object, through intramolecular cyclization reaction Synthesis of5-chloro-3-phenyl-4,5-dihydro-thiazole. The reaction conditions were optimized system. The study found that the kind of Lewis acid, Lewis acid equivalents, reaction time, temperature and additive factors have a significant effect on the reaction. However, the yield of this reaction is low, to extend the application and substrate reaction brought some limitations. Overall, the N-allylbenzothioamide cyclization opened up a new way to develop an approach based on ferric chloride effect of intramolecular cyclization thioamide.The second part mainly thioamide and nitrogen halide reagents for the study, by intramolecular cyclization Thioaceamide. The reaction conditions were optimized system. The study found that the nitrogen species of the halogenating agent, the type of the thioamide, the type of solvent and temperature conditions of factors have a significant effect on the reaction. Extension in the substrate, found that the reaction has a relatively good selectivity and high yield. In general, the development of action under a nitrogen halide reagents based on intramolecular cyclization Thioaceamide. This method step is simple, convenient and efficient, highly selective build area of4,5-dihydro-thiazole compounds.The third part to reflect the amide and organic sulfur reagents for the study, by thioamide synthesis reactions. Our reaction conditions were optimized system. The study found that the type of organic sulfur, the type of solvent and reaction time and temperature conditions factors have a significant effect on the reaction, the advantages of this reaction are under mild conditions, the use of stable, easy to store and does not taste of organic sulfur compounds. Reactions for the synthesis of thioamide opened up a new way to develop an organic base salt-based role, at room temperature, thioamide compound rapid preparation method.