2,4二甲基3氨基噻吩的合成新工艺

New Process of Synthesis of 2,4-Dimethylthiophene-3-amine

2,4-二甲基-3-氨基噻吩是一种重要的农药中间体,以琉基乙酸和乙酰丙酮为起始原料,经过亲核加成、酯化、关环、水解、脱羧、硝化、还原7步反应得到2,4-二甲基-3-氨基噻吩,并优化了酯化反应,研究了催化剂种类、用量、原料摩尔比、反应时间和共沸脱水时间对收率的影响。并采用IR、1H NMR对该化合物的结构进行了表征。与传统工艺相比,该工艺提高了产品的收率和纯度,简单经济,条件温和,适合工业化生产。

2,4-Dimethyhhiophene-3-amine is an important intermediate of pesticides, 2,4- Dimethyhhiophene-3-amine was synthesized from thioglycolic acid and acetyl-acetone as starting material via seven steps reaetons including nucleophilic addition, esterification, cyclization, hydrolysis, nitration, decarboxylation and reduction. The optimum reaction condition of esterification was studied, such as the kinds of and the quantity of catalyst, reaction time, ratio of raw material and the time of azeotropic dehydration . structure of synthesized compo was confirmed by IR,1H NMR. compared to the traditional technics, this process can improve yield and purity of the product. It is simple , warm and economical, which is suitable industrial scale manufacture. the und the forindustrial scale manufacture.