CERIUM(III) CHLORIDE MEDIATED NITRILE ALDOL REACTIONS - ENHANCED DIASTEREOSELECTIVITIES USING A CHIRAL ORGANOCERIUM COMPLEX

The addition of anhydrous cerium chloride to nitrile aldol reactions h as been found to provide high yields of beta-hydroxynitriles. Also, th e aldol reaction of alpha,beta-unsaturated carbonyl compounds with nit rile enolates in the presence of cerium chloride affords 1, 2 addition exclusively in good to excellent yields. The organocerium complexes o f R-(+)-1,1'-bi-2-naphthol have successfully mediated the aldol additi on of lithio alkyl and arylacetonitriles to aldehydes, and the reactio n gives beta-hydroxynitriles in good yields with moderate to good dias tereoselectivity. (C) 1998 Elsevier Science Ltd. All rights reserved.