Catalytic Hydrodefluorination of C-F Bonds by an Air-Stable PIII Lewis Acid.

Abstract

Catalytic hydrodefluorination (HDF) of unactivated fluoroalkanes or CF3 -substituted aryl species is performed using the PIII Lewis acids, [(bipy)PPh]2+ (12+ ) and [(terpy)PPh]2+ (22+ ) under mild conditions (25 or 50 °C). Mechanistic studies indicate that activation of C-F bond by the PIII center is key. Particularly noteworthy is that the catalyst 2[B(C6 F5 )4 ]2 is air-stable and readily accessible from bench-stable, commercially available reagents in one-step and can be used without isolation.