Activation of functional arylzincs prepared from aryl iodides and highly enantioselective addition to aldehydes

An easily available chiral ligand (S)-1 is found to activate the nucleophilic reaction of the arylzincs prepared in situ from the reaction of aryl iodides with Et2Zn. Both high yields and high enantioselectivity (up to >99% ee) for the reaction of these arylzincs with a variety of aldehydes are obtained. The mild reaction conditions and the good functional group tolerance make this catalytic asymmetric process synthetically useful.