| abstract |
ISOMERS OR PAIRS OF CRYSTALLIZABLE PYRETHROID ENANTIOMEROS BECOME MORE ACTIVE ISOMERS AS PESTICIDES BY CONTACTING A SUSPENSION THICKNESS IN HYDROCARBONS OF THE SPANISH SOUTHERN ESPANE, BASE AND A CATALYST, THE CATALYST, SEVEN ELSPAN THAT AN EFFECTIVE TEMPERATURE IS MAINTAINED, AND RECOVERING THE RESULTING ISOMERS. THE TENDENCY TO FORM ESTER BYPRODUCT OF BENZOINE IS REDUCED BY INCLUDING IN THE THICKNESS SUSPENSION A WEAK BASE, AN ALDEHYDE SWEEPING AGENT AND / OR A CATALYST DISSOLVED IN A SUITABLE SOLVENT. THE PROCEDURE IS TYPICALLY EFFECTIVE FOR ENRICHING CYPERMETRINE, CYPHLUTRINE AND 3- (2,2-DIBROMOETHENYL) -2,2-DIMETHYLCLOPROPANOCARBOXYLATE METHYL IN THE MOST ACTIVE CHEMICAL SPECIES. |