Vinylogous Aldol Reaction of a Silyloxydiene Promoted by Sulfoxides, as Lewis Bases: 1,4-asymmetric Induction Mediated by a Remote Methylsulfinyl Group

A versatile procedure for the gamma-vinylogous aldol reaction of the dioxinone-derived silyl enolether, via enolate activation with an appropriate neutral Lewis base, was formulated. High levels of diastereo- and enantioselectivity using chiral 2-methylsulfinyl benzaldehyde were obtained, pointing out the dual role of the methylsulfinyl group as incorporated chiral inductor and activator of the silyloxydiene in the stereoselective vinylogous aldol reaction.