Copper- and Iron-Catalyzed Decarboxylative Tri- and Difluoromethylation of α,β-Unsaturated Carboxylic Acids with CF3SO2Na and (CF2HSO2)2Zn via a Radical Process

A copper-catalyzed decarboxylative trifluoromethylation of various α,β-unsaturated carboxylic acids by using a stable and inexpensive solid, sodium trifluoromethanesulfinate (CF3SO2Na, Langlois reagent), was developed. In addition, an iron-catalyzed difluoromethylation of aryl-substituted acrylic acids by using zinc difluoromethanesulfinate (DFMS, (CF2HSO2)2Zn, Baran reagent) via a similar radical process was also achieved.