除草剂噻吩磺隆的合成

Synthesis of Herbicide Thifensulfuron-methyl

以氯甲酸甲酯和2-羧甲基-3-磺酰氨基噻吩为起始原料合成除草剂噻磺隆的方法。原料2-羧甲基-3-磺酰氨基噻吩与氯甲酸甲酯生成2-甲氧羰基-3-磺酰氨基甲酸甲酯噻吩, 再与2-氨基-4-甲氧基-6-甲基均三嗪反应生成噻吩磺隆。避免了异氰酸酯路线和光气法的种种缺点,具有收率高、含量高、成本低的特点。以2-羧甲基-3-磺酰氨基噻吩计,总收率为77．73％,原药纯度达到93．6％。

A method for preparation of thifensulfuron-methyl from methyl chloroformate and 2- methoxycarbonyl -3 -aminosulfonylthiophene as starting material was introduced. 2 - methoxycarbony1-3-am inosulfonylthiophene reactsed with methyl chloroformate to form 2- methoxycarbonyl-3-am inosulfonylthiophene. Thifensulfuron was obtained by the reaction of the above product with 2-amino-4-methoxy-6-methyl-1,3,5-triazine. This was an economical method to prepare thifensulfuron-methyl with high yield and good purity, avoiding the disadvantages of the isocyanate route. The total yield could reach to 77.73% based on 2- methoxycarbonyl-3-am inosulfonylthiophene and the purity could reach to 93.6%.