Rh-Catalyzed Asymmetric Arylation of Aldehydes with Arylboronic Acids

Significance

The direct enantioselective preparation of diarylcarbinols from arylboronic acids and benzaldehydes is highly attractive for the synthesis of biologically active molecules, as it offers an optimal functional group compatibility compared to other methods. So far, only moderate enantio­selectivities were achieved in a Rh-catalyzed process, using expensive ligands. The development of a new catalytic system for this reaction is therefore highly desirable. This method, although providing intermediate to good enantiomeric excesses, is a significant step forward in this field. The BINOL-based ligand used here is simple to prepare from inexpensive starting materials. The loadings of Rh catalyst and ligand are not high, and the protocol is operationally very simple.