ENANTIOMERIC PAIR OF 1R,CIS-S AND 1S,CIS-R ISOMERS OF CYHALOTHRIN,AND A PROCESS FOR THEIR SEPARATION FROM AN ISOMERIC MIXTURE OF FOUR ISOMERS AND INSECTICIDAL COMPOSITIONS CONTAINING THEM

摘要

There is provided a novel crystalline material consisting of an enantiomeric pair of cyhalothrin isomers having greater insecticidal activity than cyhalothrin itself, and a process for obtaining the crystalline material by crystallisation from concentrated cyhalothrin solutions in lower alkanols or liquid alkanes. The crystalline material may be obtained in the form of either the racemic mixture or the racemic compound of the isomer pair.