Process for the preparation of pyrethroids

摘要

Preparation of compounds of general formula I: <IMAGE> in which R is a halogen atom or a C1-4 alkyl radical. A compound of formula II: <IMAGE> in which R is as above, is reacted with an alkaline phenoxide of general formula III: <IMAGE> in the presence of a catalyst based on copper and/or on a copper(I) salt. Preparation of pyrethroids with insecticidal use.