Copper‐Catalyzed Preparation of Ketones Bearing a Stereogenic Center in α Position

A highly enantioselective synthesis of α-alkylated and -arylated ketones can be achieved by using a reaction sequence consisting of a stereoselective anti-SN2′ allylic substitution in the presence of CuCN⋅2 LiCl following by the oxidation of an intermediate cycloalkenyl lithium species using (Me3SiO)2 or (MeO)3B/NaBO3⋅4 H2O.