2-氨基-2-噻唑啉-4-羧酸的合成研究

由丙烯酸出发 ,经氯化、脱氯化氢、加成、环合 ,制得化合物 2 氨基 2 噻唑啉 4 羧酸 (dl ATC )。以四氯化碳为溶剂 ,丙烯酸与其质量 0 2 3%的自制铜基复合阻聚剂混合 ,于 5 0℃下通入氯气 ,氯化制得 2 ,3 二氯丙酸。此法采用自制铜基复合阻聚剂大大降低了丙烯酸氯化时的聚合副反应 ,收率达86 % ,是文献值的 2 4 7倍。同时将后 3步反应并成一锅法反应 ,简化了操作。 2 ,3 二氯丙酸先与 2倍物质的量的氢氧化钠在 35℃反应 5h,然后加入 3倍物质的量的浓盐酸和等物质的量的硫脲于 80～83℃反应 3h ,再与 1 5倍物质的量的碳酸钠反应得产品。收率由文献值的 6 3%提高到 90 %以上。此外还建立了用高效液相色谱定量测定dl ATC的方法 ,w(dl ATC) =96 %

Synthesis of 2-Amino-2-thiazoline-4-carboxylic Acid

From acrylic acid,2 amino 2 thiazoline 4 carboylic acid is prepared through chlorination,dehydrochlorination,addition and cyclization reactions.Thus,acrylic acid was chlorinated in the presence of 0 23% portion of inhibitor,which is made by our lab,at 50 ℃ to obtain 2,3 dichloropropionic acid.Polymerization of acrylic acid during chlorination is decreased greatly by using such inhibitor and yield of dichloropropionic acid can reach 86%,2 47 times as high as that in the literature.The following three reaction steps are carried out in one pot.Thus,1 mole of 2,3 dichloropropionic acid reacted with 2 moles of sodium hydroxide in water at 35 ℃ for 5 h,then 3 moles of conc.hydrochloric acid and 1 mole of thiourea were added and stirred at 80-83 ℃ for 3 h,and finally,1 5 moles of solid sodium carbonate were added and treated to get the final product.In this way,not only the procedures are simplified,but also the yield is increased from 63% in literature to more than 90%.Also the quantitative analytical method using HPLC is established.