Recent progress in asymmetric two-center catalysis
Abstract
Recent progress using two types of enantioselective two-center catalysts, Lewis acid–Brönsted base and Lewis acid–Lewis base bifunctional complexes, is described. The first part of this review discusses improvements in the syn-selective direct catalytic enantioselective aldol reaction and 1,4-addition reaction of a 2-hydroxyacetophenone derivative using a Zn-linked-BINOL complex. In the second part, we describe the development of catalysts displaying Lewis acidity and Lewis basicity in a catalytic enantioselective cyanosilylation of aldehydes and the logical extension to a tetrasubstituted carbon synthesis through a Reissert-type reaction and a cyanosilylation of ketones.