PRODUCTION OF SYNTHETIC PYRETHROID BY AZEOTROPIC ESTERIFICATION

摘要

Preparation of 2,3,5,6-tetrafluorobenzyl 3-alkenyl-2,2-dimethylcyclopropane-3-carboxylate derivative synthetic pyrethroids of formula (I) involves azeotropically esterifying the corresponding carboxylic acid of formula (II) with 2,3,5,6-tetrafluorobenzyl alcohol (III). R<1>,R<2> = Me, CHF2, CF3 or Cl.