基于重氮化和Meerwin芳基化的 “一锅法”合成唑草酮工艺

One-pot Synthesis Process of the Carfentrazone-ethyl Based on Diazotization and Meerwin Arylation Reaction

摘要:

以氯化亚铜(CuCl)为催化剂，亚硝酸叔丁酯(t-BuONO)为重氮化试剂，在溶剂乙腈或丁酮中，1-(5-氨基-2-氟-4-氯苯基)-3-甲基-4-二氟甲基-1H-1,2,4-三唑啉-5-酮（TZLO-A）经重氮化和Meerwin芳基化“一锅法”制备得到目标化合物唑草酮，产物经1HNMR、13CNMR和MS表征。合成条件经实验优化，确定了最佳反应条件：n(TZLO-A):n(氯化亚铜):n(丙烯酸乙酯):n(亚硝酸叔丁酯)=1:(0.6-0.7):13.7:1.5，盐酸(HCl)和亚硝酸叔丁酯滴加时间分别为20 min和150 min，产品收率达到了92.9%，HPLC色谱含量为92%。

Abstract:

Carfentrazone-ethyl was synthesized by one-pot reaction with 1-(5-amino-4-chloro-2- fluorophenyl)-4-(difluoromethyl)-3-methyl-1H-1,2,4-triazol-5(4H)-one(TZLO-A) as raw materials, copper(Ⅰ) chloride(CuCl) as catalyst and t-butyl nitrite(t-BuONO) as diazotized reagent through diazotization and Meerwin arylation reaction in acetonitrile or butanone. The structure of the product was characterized by 1HNMR、13CNMR and MS spectrum. The optimum reaction conditions of synthesis were obtained as follows: the molar ratio of TZLO-A, copper(Ⅰ) chloride, ethyl acrylate, to t-butyl nitrite was 1:(0.6-0.7):13.7:1.5, the adding time of hydrochloric acid and t-butyl nitrite was 20 min and 150 min respectively. Under these conditions, the target product was obtained with a yield of 92.9% and with a purity of 92%.