溴虫腈的合成

Synthesis of chlorfenapyr

以对氯苯甘氨酸、三氟乙酸、2-氯丙烯腈为原料,经内酯化、吡咯环化、溴代和乙氧甲基化4步反应合成溴虫腈,总收率大于73.4%,纯度大于99%,均高于国内同行水平4%～5%。该路线采用价格低廉的三氟乙酸和二乙氧基甲烷代替昂贵的三氟乙酸酐和二溴甲烷,大大降低了原料成本,避免了强致癌物的使用,条件温和,对工艺要求不高,所有原料在国内皆有生产,来源丰富,适宜于工业化生产。

Chlorfenapyr was synthesized with chlorophenylglycine, trifluoroacetic acid and 2-chloroacrylonitrile by four steps via lactonization, pyrrole cyclization, bromization and ethoxymethylizafion. Overall yield was over 73.4% and purity was over 99%, which was 4%-5% higher than the domestic average level. The expensive trifluoroacetic anhydride and dibromomethane were replaced by trifluoroacetic acid and methylene diethyl ether respectively. Carcinogen was avoid use. The raw materials were abundant and the reaction condition was mild, so this way could be turned into industrialization.