Kinetic Resolution of 2,3-Dihydro-2-substituted 4-Quinolones by Palladium-Catalyzed Asymmetric Allylic Alkylation

The kinetic resolution of a carbon nucleophile is realized for the first time via Pd-catalyzed asymmetric allylic alkylation with "unstabilized" ketone enolates as the nucleophile, providing both allylated 2,3-disubstituted 2,3-dihydro-4-quinolones and recovered substrates in high yields and high ee (S-factor is 40-145). The application of the methodology in organic synthesis is demonstrated by the ready transformation of an allylated adduct into pyrrolo[3,2-c]quinoline, which features a core structure of biologically active Martinella alkaloids.