Theoretical studies of the role of complexation in the conjugate addition of dialkylcuprates to electron-deficient CC bonds. Influence on the stereochemistry of the reaction

Abstract

Ab initio molecular orbital calculations suggest that dialkylcuprates add to conjugated CC bonds via a mechanism which involves pre-complexation of the copper centre with the double bond, implying an acute angle of attack onto the CC bond; this may explain the opposite stereoselectivities observed in the reactions of dialkylcuprates on the one hand and of alkylcopper reagents (and other conventional nucleophiles) on the other.