Catalytic Asymmetric Access to α,β Unsaturated δ-Lactones through a Vinylogous Aldol Reaction:  Application to the Total Synthesis of the Prelog-Djerassi Lactone

Abstract

[reaction--see text] A one-step catalytic asymmetric access to alpha,beta unsaturated delta-lactones is described, using a vinylogous Mukaiyama-aldol reaction between a gamma-substituted dienolate and various aldehydes in the presence of Carreira catalyst CuF.(S)-tolBinap. This methodology has been further applied to a straightforward access to the Prelog-Djerassi lactone.