Enantioselective Construction of All‐Carbon Quaternary Stereocenters Using Palladium‐Catalyzed Asymmetric Allylic Alkylation of γ‐Acetoxy‐α,β‐unsaturated Carbonyl Compounds

We have successfully demonstrated that γ‐acetoxy‐α,β‐unsaturated carbonyl compounds are useful starting materials for Pd‐catalyzed asymmetric allylic alkylation to construct all‐carbon quaternary stereocenters. With the use of 2–5 mol % of Pd catalyst and 4–10 mol % of P‐chirogenic diaminophosphine oxides, asymmetric allylic alkylation of γ‐acetoxy‐α,β‐unsaturated carbonyl compounds with various prochiral nucleophiles derived from cyclic β‐keto esters proceeded in the presence of Zn(OAc) 2 , providing the corresponding products with an all‐carbon quaternary stereocenter in up to 95% ee.