Remote Stereoinduction in the Organocuprate-Mediated Allylic Alkylation of Allylic <i>gem</i>-Dichlorides: Highly Diastereoselective Synthesis of (<i>Z</i>)-Chloroalkene Dipeptide Isosteres

Abstract

Highly diastereoselective synthesis of (Z)-chloroalkene dipeptide isosteres has been achieved by 1,4-asymmetric induction in the organocuprate-mediated allylic alkylation adjacent to the chiral center of allylic gem-dichlorides. The reaction proceeds with a variety of heterocuprates prepared from CuCN and various organometallic reagents. It allows rapid construction of valuable architectures of L,D-type and L,L-type (Z)-chloroalkene dipeptide isosteres from the corresponding (E)- and (Z)-allylic gem-dichlorides in high yields, with excellent (Z)-selectivity and diastereoselectivity.