8-氟-5-甲氧基-1,2,4-三唑并[4,3-c]嘧啶-3(2H)-硫酮的合成
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摘要
以5-氟尿嘧啶为起始原料,经氯代反应、醇解反应、肼解反应和环合反应合成了高效除草剂双氟磺草胺的关键中间体—8-氟-5-甲氧基-1,2,4-三唑并[4,3-c]嘧啶-3(2H)-硫酮。以5-氟尿嘧啶计,产品总收率达70.1%,产品结构经核磁共振分析验证。探讨了原料配比、反应温度、时间等因素对反应收率的影响。
Using 5-fluorouracil as starting material,8-fluoro-5-methoxy-2H-[1,2,4]triazolo[4,3-c]pyrimidine-3-thione was synthesized by chlorination,alcoholysis,hydrazinolysis,cyclization,in a total yield of 70.1 %,which is a key intermediate of florasulam.The structure of 5-fluorouracil was confirmed by NMR analysis.The influence of the ratio of reactants,temperature and time factor on the yield was investigated.
Using 5-fluorouracil as starting material,8-fluoro-5-methoxy-2H-[1,2,4]triazolo[4,3-c]pyrimidine-3-thione was synthesized by chlorination,alcoholysis,hydrazinolysis,cyclization,in a total yield of 70.1 %,which is a key intermediate of florasulam.The structure of 5-fluorouracil was confirmed by NMR analysis.The influence of the ratio of reactants,temperature and time factor on the yield was investigated.
引文
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