Phosphine-Catalyzed Z-Selective Carbofluorination of Alkynoates Bearing an N-Heteroarene Unit

Abstract

AbstractWe report herein on the phosphine-catalyzed Z-selective carbofluorination of alkynoates bearing an N-heteroarene unit, by using acyl fluorides as bifunctional reagents. This reaction proceeds through a pentacoordinate fluorophosphorane(V) intermediate, resulting in the formation of a C–F bond by a ligand coupling process. The Z-selectivity is attributed to the thermodynamic stabilization of a Z-isomer by orbital interactions between lone pair electrons of an N-heteroarene and the π* orbital of a carbonyl group.