Affiliation:
1. Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
2. University of Chinese Academy of Sciences Beijing 100049 China
Abstract
Comprehensive SummaryThe asymmetric partial reduction of 1,3‐diketones stands as a straightforward pathway to access optically active β‐hydroxyketones. In this paper, an asymmetric Piers‐type hydrosilylation of 2,2‐difluoro‐1,3‐diketones was successfully realized by using a frustrated Lewis pair of chiral borane and tricyclohexylphosphine as a catalyst, delivering a variety of α,α‐difluoro‐β‐hydroxyketones in high yields with up to 99% ee. Significantly, no over‐reduced diol products were observed even with an excess amount of silanes. The product can be conveniently converted to α,α‐difluoro‐β‐hydroxyester or 1,3‐anti‐diol via an oxidation with m‐CPBA or a reduction with DIBAL‐H without obvious loss of ee.