Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation of Dihydroquinolinones.

ABSTRACT

A palladium-catalyzed decarboxylative asymmetric allylic alkylation (Pd-DAAA) of benzo-fused and non-benzo-fused δ-valerolactams is disclosed. This methodology gives access to chiral lactams bearing C3-quaternary stereocenters, which are central to many natural products and biologically active compounds. The reaction proceeds via palladium-catalyzed ionization of an allyl ester, followed by carbon dioxide extrusion and recombination of the electrophilic Pd-π-allyl complex with the in situ generated lactam enolate. This final step converts racemic allylic ester starting materials into enantiomerically enriched substituted lactams with high yield and enantiomeric excess.