A magnesium enamide derived from N-2-(N′,N′-dimethylamino)ethylimine reacts with primary and secondary alkyl chlorides and fluorides to give an α-alkylated ketone in good to excellent yields upon hydrolysis of the imine moiety. Reactions of the highly nucleophilic magnesium enamide derived from an unsymmetrical ketone take place regioselectively. In addition, the C–C bond formation is stereospecific: