Direct Formation of Secondary and Tertiary Alkylzinc Bromides and Subsequent Cu(I)-Mediated Couplings
作者:Reuben D. Rieke、Mark V. Hanson、Jeffrey D. Brown、Q. Jason Niu
DOI:10.1021/jo952104b
日期:1996.1.1
Secondary and tertiary alkylzinc bromides can be generated from the direct oxidative addition of Rieke zinc to secondary and tertiary alkyl bromides in high yield. These organozinc reagents have been found to undergo copper-catalyzed conjugate addition, cross-coupling with acid chlorides, and carbocupration to activated alkynes.
A highly efficient method for kineticresolution of racemic aliphatic alcohols without conversion of the hydroxyl group has been realized; the method involves hydrogenation mediated by a remote ester group and is catalyzed by a chiral iridium complex. This powerful, environmentally friendly method provides chiral δ-alkyl-δ-hydroxy esters and δ-alkyl-1,5-diols in good yields with high enantioselectivities