唑草酮的合成工艺改进

Improvement of Synthesis Process of Carfentrazone-ethyl

现有最唑草酮的合成路线存在成本高、收率低等缺点。本文对唑草酮的合成工艺进行改进和优化,并建立每一步的质量标准。以邻氟苯胺为原料,经“一锅法”完成氨基保护和氯代,然后经水解、重氮化、“一锅法”制三唑啉酮、氟甲基化、硝化、还原、Meerwein芳基化和酯化9步反应,使用HPLC对反应进行中控,以33.37%的总收率(以邻氟苯胺计),99.12%的纯度得到唑草酮。产物与中间体结构经HPLC-MS和NMR确证。该方法原料安全易得、价格低廉,产品的纯度和收率良好,节省反应时间和设备,适合工业化生产。

The current production route of carfentrazone-ethyl has defects such as high cost and low yield.In this paper,the synthesis process of carfentrazone-ethyl was improved and optimized,and the quality standards for each step was established.Using o-fluoroaniline as raw material,amino-protected and chlorinated are completed in one pot,and then hydrolysis,diazotization,“one-pot method”to prepare triazolinone ring,fluoromethylation,nitration,reduction,Meerwein arylation and esterification 9-step reaction,with a total yield of 33.37%(calculated by o-fluoroaniline)and a purity of 99.12%to obtain carfentrazone-ethyl.The reaction was controlled by HPLC,and structures of the product and intermediates were confirmed by HPLC-MS and NMR characterization.The method is safe and easy to obtain raw materials,low in price,good in product purity and yield,saves reaction time and equipment,which is suitable for industrial production.