Palladium(0)-Catalyzed Enantioselective Construction of Multifunctional Piperidine Derivatives from 1,3-Dienes, N -Cyano Imines, and Beyond.

An enantioselective (4 + 2) reaction between 1,3-dienes and N -cyano imines has been developed under Pd(0) catalysis, proceeding through a cascade vinylogous addition and intramolecular allylic amination sequence. 2,6- cis -Disubstituted-1,2,3,6-tetrahydropyridines were furnished as single diastereomers in moderate to good yields and enantiocontrol. Moreover, a more challenging three-component (2 + 2 + 2) annulation of 1,3-dienes, N -cyano imines, and activated alkenes was efficiently realized to afford piperidines with high structural complexity, albeit with moderate enantioselectivity.