α,β-Unsaturated δ-Lactones from Copper-Catalyzed Asymmetric Vinylogous Mukaiyama Reactions of Aldehydes: Scope and Mechanistic Insights

Abstract

A direct regio-, diastereo-, and enantiocontrolled access to a,߭unsaturated d-lactones is described, based on the reaction of a silyl dienolate and an aldehyde in the presence of 10 % of Carreira's catalyst. The scope and limitations of this reaction, as well as mechanistic insights concerning the reactivity of an allyl copper species, are discussed.