Enantioselective Synthesis of β,γ-Unsaturated α-Fluoroesters Catalyzed by N-Heterocyclic Carbenes

摘要

Chiral organofluorine compounds have attracted increasing attention because of their valuable applications in pharmaceutical, agrochemical, and materials industries.Thus, the development of catalytic enantioselective C—F bond-formation processes has become an important area in organic synthesis.In particular, the stereocontrolled fluorination at the a position of a carbonyl group has been intensively explored.Since the first report by Hintermann and Togni in 2000, a range of catalytic enantioselective a fluorination of carbonyl compounds have been developed. Despite the significant progress, there remains a great need for further development of useful enantioselective fluorination processes. For example, organocatalyzed asymmetric fluorination for the synthesis of simple a-fluoroesters remains unknown. Herein, we report the first enantioselective fluorination reaction catalyzed by N-heterocyclic carbenes (NHCs).