A Palladium-Catalyzed Asymmetric Allylic Alkylation Approach to α-Quaternary γ-Butyrolactones.

The Pd-catalyzed asymmetric allylic alkylation (Pd-AAA) of enol carbonates derived from γ-butyrolactones is reported, affording the corresponding enantioenriched α,α'-disubstituted γ-butyrolactones in both high yields and high enantioselectivities (up to 94% ee). This method was eventually applied to the synthesis of chiral spirocyclic compounds.