2,3,5,6-四氟苯甲醇的合成

经氟代、水解脱羧、酯化、还原等步骤合成了杀虫剂四氟苯菊酯的重要中间体2,3,5,6-四氟苯甲醇, 改进了氟代反应的无水操作和反应条件, 产物四氟对苯二甲腈纯度高达98.3%, 通过加入水参与反应改进了水解反应, 使水解和脱羧由两步反应变为一步, 且产物为只脱一个羧基的2,3,5,6-四氟苯甲酸, 收率可以高达92.5%, 用相对价廉的NaBH₄/I₂体系还原2,3,5,6-四氟苯甲酸甲酯以52.3%的收率得到了目标产物, 总收率29.6%.

Synthesis of 2,3,5,6-Tetrafluorobenzyl Alcohol

2,3,5,6-Tetrafluorobenzyl alcohol, the important intermediate of insecticide transfluthrin, was synthesized through fluorination, hydrolysis, decarboxylation, esterification and reduction. Using anhydrous DMF in fluorination step, the yield of tetrafluoro-terephthalonitrile could be improved to 70.3%, with purity of 98.3%. The hydrolysis and decarboxylation occurred in one step by addition of water, and the yield of product 2,3,5,6-tetrafluorobenzoic acid was 92.5%. 2,3,5,6-Tetrafluorobenzyl alcohol was yielded with 52.3% by reduction of methyl 2,3,5,6-tetrafluorobenzoate with NaBH4/I2. Total yield was 29.6%.