Benzylic Phosphates as Electrophiles in the Palladium-Catalyzed Asymmetric Benzylation of Azlactones

Palladium-catalyzed asymmetric benzylation has been demonstrated with azlactones as prochiral nucleophiles in the presence of chiral bisphosphine ligands. Benzylic electrophiles are utilized under two sets of reaction conditions to construct a new tetrasubstituted stereocenter. Electron density of the phenyl ring dictates the reaction conditions, including the leaving group. The reported methodology represents a novel asymmetric carbon carbon bond formation in an amino acid precursor.