Deoxyfluorination of Carboxylic, Sulfonic, Phosphinic Acids and Phosphine Oxides by Perfluoroalkyl Ether Carboxylic Acids Featuring CF2O Units

Main observation and conclusion The deoxyfluorination of carboxylic, sulfonic, phosphinic acids and phosphine oxides is a fundamentally important approach to access acyl fluorides, sulfonyl fluorides and phosphoric fluorides, thus the development of inexpensive, stable, easy‐to‐handle, versatile, and efficient deoxyfluorination reagents is highly desired. Herein, we report the use of potassium salts of perfluoroalkyl ether carboxylic acids (PFECA) featuring CF 2 O units as deoxyfluorination reagents, which are generated mainly as by‐products in the manufacture of hexafluoropropene oxide (HFPO). The synthesis of acyl fluorides, sulfonyl fluorides and phosphoric fluorides can be realized via carbonic difluoride (COF 2 ) generated in situ from thermal degradation of the PFECA salt.