α-巯基噻唑啉的合成改进

A Study of Synthesis of 2-Mercaptothiazoline

以硫酸、乙醇胺和二硫化碳为主要原料，经酯化，成环，合成2-巯基二氢噻唑啉。探讨了混合温度、物料比、反应温度等对反应收率的影响。得出的最佳工艺条件为：20℃时，将乙醇胺和硫酸以1：1．2的摩尔比混合，在45-145℃范围内减压蒸馏得2-氨基乙基硫酸酯，再与二硫化碳在碱性条件下反应生成α-巯基噻唑啉。产物收率均达到90％以上，较国内平均水平提高了20％以上。产物结构用1^HNMR和MS进行表征确证。合成过程操作简单，原料易得，条件温和，成本低，产率高。

2-mercaptothiazoline is prepared by sulfuric acid,ethanolamine and carbon disulfide. The process route of synthesis 2-mercaptothiazoline, esterification and cyclization is established. The effects of the mole ratio of materials, mixture temperature and reaction temperature are discussed. The optimum conditions are givenly stirring the mixture solution containing 50% sulfuric acid and 70% ethanolamine solution, at 20 ℃, n（ethanolamine） ： n（ sulfuric acid） = 1： 1.2, for 30 minutes. The solution is distilled at the vacuum 0. 095 MP and temperature from 45 ℃ to 145℃, 2-aminoethysulfate produced after the proceeding. 2-aminoethysulfate reacted with carbon disulfide at basic solution and the target product got. Its yield is above 90%, higher 20% than other regions in China. Its structure is confirmed by 1^HNMR and MS . The results show that the product is 2-mercaptothiazoline. Compared with the precious methods, this new method has the advantages of simple procedure, milder reaction conditions, easier obtained material, economic and good yield.