Abstract: Compounds of formula R.sup.3 --CH.dbd.CH--CR.sup.1 R.sup.2 --CH.sub.2 OCH.sub.2 R.sup.4 wherein R.sup.1 and R.sup.2 are H, alkyl or together form a cycloalkyl group with the adjacent carbon, R.sup.3 is a substituted phenyl group, R.sup.4 is an optionally subsituted phenoxy phenyl group, and compositions containing them useful as insecticides, and compounds of formula HOCH.sub.2 --CR.sup.1 R.sup.2 --CH.sub.2 OCH.sub.2 R.sup.4 and OCH--CR.sup.1 R.sup.2 CH.sub.2 OCH.sub.2 R.sup.4, useful as intermediates therefor.

Abstract: 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-dimethylcyclopro pane 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-dimethylcyclopro pane 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-dimethylcyclopro pane 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-dimethylcyclopro pane carboxylate in an organic solvent to the action of a base to effect epimerization.