Enantioselective allylation of β,γ-unsaturated aldehydes generated via lewis acid induced rearrangement of 2-vinyloxiranes

GRAPHICS 2-Vinyloxiranes have been found to be excellent surrogates to beta,gamma-unsaturated aldehydes. These valuable electrophiles, generated in situ by treatment of a 2-vinyloxirane with a catalytic amount of Sc(OTf)(3), are effectively trapped by the chiral allylating agents based on alpha-pinene, affording bishomoallylic alcohols in high yield and excellent selectivity.