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

[目的]制备氯虫酰胺的重要中间体3-溴-1-(3-氯-2-吡啶基)-1H-吡唑-5-甲酸。[方法]以2,3-二氯吡啶为原料,经肼解、环合、溴化、氧化、水解制得3-溴-1-(3-氯-2-吡啶基)-1H-吡唑-5-甲酸。[结果]在优化的条件下,反应总收率为41.87%(以2,3-二氯吡啶计),含量为98.5%,其结构经1H NMR分析确认。[结论]该工艺简单经济,条件温和,适合工业化生产。

[Aims] The important intermediate 3-bromo-1-（3-chloro-2-pyridinyl）-1H-pyrazole-5-carboxylic acid for synthesizing chlorantraniliprole was prepared.[Methods] 3-Bromo-1-（3-chloro-2-pyridinyl）-1H-pyrazole-5-carboxylic acid can be obtained through hydrazinolysis,cyclization,bromination,oxidation and hydrolysis reactions using 2,3dichloro-pyridineas as starting material.[Results] The total yield was 41.87% based on 2,3-dichloropyridine under the optimized reaction conditions and purity was as high as 98.5%.The structure of the end product was confirmed by1H NMR.[Conclusions] This process is simple,warm,and economical,which is very suitable for industrialized production.