ENANTIOMERIC PAIR OF ISOMERS CONSISTING OF ALPHA-CYANO-4-FLUORO-3-PHENOXY-BENZYL 3-(2-CHLORO-3,3,3-TRIFLUOROPROP-1-EN-1-YL)-2,2-DIMETHYLCYCLOPROPANE CARBOXYLATE,PROCESS FOR THEIR PREPARATION AND INSECTICIDAL COMPOSITIONS CONTAINING THEM

摘要

A process for the relative enrichment of a solution of alpha -cyano-4-fluoro-3-phenoxybenzyl 3-(Z-2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylate with respect to the enantiomeric pair of isomers represented by (S)- alpha -cyano-4-fluoro-3-phenoxybenzyl (1R,cis)-3-(Z-2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcycl opropane carboxylate and (R)- alpha -cyano-4-fluoro-3-phenoxybenzyl (1S,cis)-3-(Z-2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcycl opropane carboxylate which comprises subjecting a solution comprising the enantiomeric pair of isomers (R)- alpha -cyano-4-fluoro-3-phenoxybenzyl (1R,cis)-3-(Z-2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcycl opropane carboxylate and (S)- alpha -cyano-4-fluoro-3-phenoxybenzyl (1S,cis)-3-(Z-2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcycl opropane carboxylate in an organic solvent to the action of a base to effect epimerization.