Diastereoselective epoxidation of compound bearing a cyclohex-3-enol moiety: Application to the enantioselective synthesis of (1R)-trans-chrysanthemic acid and (1R)-cis-deltametrinic acid

We disclose the synthesis of enantiomeric (1S)-cis- and (1R)-cis-chrysanthemic acids precursors of S-bioallethrin and deltamethrin the most active indoor and outdoor insecticides respectively. It involves an original strategy which takes advantage of the complete stereocontrolled epoxidation of an homoallylalcohol and the synthesis in the same pot of precursors of each of the two enantiomers of cis-chrysanthemic acid, bearing functional groups possessing similar reactivity but having different structural behavior which allow their easy separation.