Interruption of Formal Schmidt Rearrangement/Hosomi-Sakurai Reaction of Vinyl Azides with Allyl/Propargylsilanes.

An interrupted Schmidt rearrangement/Hosomi-Sakurai reaction of N-tosyl and S-substituted vinyl azides is reported. With BF3·Et2O as a Lewis acid promoter, the denitrogenative fragmentation of vinyl azides facilitates the generation of the N/ S-stabilized carbocations, which further undergo nucleophilic addition by allyl/propargylsilanes for C-C bond formation. As a result, a variety of homoallylic/allenylic amines can be afforded in good yields under mild reaction conditions with well-defined functional-group tolerance.