(ALLYLTHIO)ACETATE DIANION AS A NEW AND CONVENIENT REAGENT FOR THE STEREOSELECTIVE SYNTHESIS OF (2E,4E)DIENOATES FROM ALKYL HALIDES

Abstract
Treatment of (allylthio)acetate with lithium diisopropylamide followed by the addition of s-butyllithium produced a new dianion which could react with a variety of alkyl halides exclusively at the allylic position. The high regioselectivity of the allylic alkylation could be realized in the case of methyl (allylthio)acetate dianion. A convenient and general method for the stereoselective synthesis of (2E,4E)dienoates from alkyl halides has been developed.