Diastereoselective Synthesis of Monofluorocyclohexenes through Photocatalyzed Cascade Cyclization of gem‐Difluoroalkenes and α,β‐Unsaturated Carbonyl Compounds

Abstract

AbstractMonofluoroalkenes are nonhydrolyzable mimetics of amides. Previous work focused on the synthesis of non‐cyclic monofluoroalkenes. However, diastereoselective synthesis of monofluorocyclohexenes from non‐cyclic substrates is challenging. Herein, we report the first photocatalyzed cascade cyclization reactions of readily available α,β‐unsaturated carbonyl compounds and gem‐difluoroalkenes for the synthesis of highly functionalized monofluorocyclohexenes. The reaction shows broad substrate scope with high diastereoselectivity (>30 examples, up to 86 % yield, >20 : 1 dr). The post‐reaction transformations of the products demonstrate the synthetic potential of this methodology.