Asymmetric Construction of Acyclic 1,3-Nonadjacent Stereogenic Centers Containing a Tetrasubstituted Carbon through Diastereoselective Alkylation of Benzyl Sulfone Derivatives

Abstract

A strategy for the asymmetric construction of acyclic 1,3-nonadjacent stereogenic centers containing a tetrasubstituted carbon has been established, which involves an enantioselective addition reaction and a subsequent chelate-controlled diastereoselective alkylation reaction. Specifically, the enantioselective addition reaction of α-thioacetamides with α-phenyl-substituted vinyl sulfones under chiral Brønsted base catalysis and the subsequent LDA-mediated diastereoselective methylation, allylation and benzylation at the α position of the sulfonyl group of the adducts afforded the desired enantio-enriched products having 1,3-nonadjacent stereogenic centers containing a tetrasubstituted carbon in a highly stereoselective manner.