Enantioselective 1,2-addition of Grignard reagents to aldehydes using chiral diamine 1, 2 was examined. High ee (up to 75%) of carbinol was achieved by the reaction of arylmagnesium bromide and benzaldehyde with chiral diamine. Utilizing 2,4,6-trimethylphenoxyaluminum dichloride 6 as a coordinating agent to benzaldehyde, enantioselectivity of the addition of alkylmagnesium bromide was dramatically increased (up to 70%).