Phosphine-Catalyzed Acyl-Group Exchange Reaction of Carboxylic Acids and an Aroyl Fluoride

Acyl fluorides show unique reactivity and stability, and the catalytic conversions using acyl fluorides as a divergent building block have recently attracted much attention and have been rapidly researched. Thus, a development of a new synthetic method of acyl fluorides is constantly demanded. Herein, we describe a phosphine-catalyzed acyl-group exchange reaction between carboxylic acids and an aroyl fluoride. A variety of acyl fluorides are directly obtained from carboxylic acids through a catalytic system composed of tricyclohexylphosphine (PCy₃) and 2,6-difluorobenzoyl fluoride. This report is the first example of utilizing an acyl fluoride as a deoxyfluorination reagent.