3-溴-1-(3-氯-2-吡啶基)-1H-吡唑-5-甲酸的合成  

Synthesis of 3-Bromo-1-(3-chloro-2-pyridinyl)-1H-pyrazole-5-carboxylic Acid

作　　者：陈一芬[1] 臧佳良[1] 冀亚飞[1] 

机构地区：[1]华东理工大学药学院,上海200237

出　　处：《合成化学》2009年第6期726-728,共3页Chinese Journal of Synthetic Chemistry

摘　　要：以2,3-二氯吡啶为起始原料,通过水合肼亲核取代、马来酸二乙酯环合制得2-(3-氯-2-吡啶基)-5-氧-3-吡唑烷甲酸乙酯(5);5经苯磺酰氯酯化、溴化氢溴化制得3-溴-1-(3-氯-2-吡啶基)-4,5-二氢-1H-吡唑-5-甲酸乙酯(7);7经脱氢、水解合成了用于制备氯虫酰胺的关键中间体——3-溴-1-(3-氯-2-吡啶基)-1H-吡唑-5-甲酸,总收率39.5%,其结构经1H NMR和MS确证。Ethyl 2-（ 3-chloro-2-pyridinyl ） -5-oxo-3-pyrazolidinecarboxylate （ 5 ） was prepared from 2,3-dichloropyidine by nucleophilic substitution with aqueous hydrazine, and then cyclization with di- ethyl maleate. Ethyl 3-bromo-1-（ 3-chloro-2-pyridinyl）-4,5-dihydro-lH-pyrazole-5-carboxylate （ 7 ） was prepared from 5 by esterification with benzenesulfonyl chloride, and then bromination with hydrogen bromide. A key intermediate for preparing chlorantraniliprole, 3-bromo-1-（3-chloro-2-pyfidinyl）- 1H-pyrazole-5-carboxylic acid （1） , was synthesized from 7 by dehydrogenation and hydrolysis in overall yield of 39.5%. The structures were confirmed by 1H NMR and MS.

关 键 词：氯虫酰胺 吡啶 吡唑 合成 

分 类 号：O626[理学—有机化学] TQ463.5[理学—化学]