Highly Regio-and Enantioselective Asymmetric Hydroformylation of Olefins Mediated by 2,5-Disubstituted Phospholane Ligands

摘要

Asymmetric hydroformylation(AHF)is a powerful synthetic methodology that allows conversion of olefins into optically active aldehydes in a single step [Eq.(I)].'1' The aldehyde group is one of the most versatile functional groups and can be readily transformed into a variety of high-value-added chiral chemicals,such as amines,imines,alcohols,and acids. Even though AHF offers great promise to the fine-chemical industry,this reaction has not been utilized on a commercial scale because of several remaining technical challenges;among the most important to overcome are a)low reaction rates at low temperatures for reactions in which good selectivities are usually observed,b)difficulties in controlling