Electrochemical Trifluoromethoxylation of (Hetero)aromatics with a Trifluoromethyl Source and Oxygen

Trifluoromethoxylated aromatics (ArOCF 3 ) are valuable structural motifs in the area of drug discovery due to the enhancement of the desired physicochemical properties upon the introduction of the trifluoromethoxy group (CF 3 O). Although significant progress has been made recently in the introduction of CF 3 O group into aromatics, current methods either require the use of expensive trifluoromethoxylation reagents or suffer from harsh reaction conditions. Here we present a conceptually new and operationally simple protocol for the direct C-H trifluoromethoxylation of (hetero)aromatics by the combination of the readily available trifluoromethylating reagent and oxygen under electrochemical reaction conditions. This reaction proceeds through the initial generation of CF 3 radical followed by conversion to CF 3 O radical, addition to (hetero)aromatics and rearomatization. The utility of this electrochemical trifluoromethoxylation is illustrated by the direct incorporation of CF 3 O group into a variety of (hetero)aromatics as well as bio-relevant molecules.