Visible-light-promoted generation of p-(N,N-dimethyl)benzyl equivalents and their reactions with quinols: easy access to diarylalkanes

The development and applications of novel synthetic intermediates are essential for synthetic chemistry. alpha-Amino alkyl radicals have been proven to be promising synthetic intermediates for the construction of versatile natural products and drugs. However, high reduction potentials of imines and further oxidation of the generated alpha-amino alkyl radicals limit their applications. Herein, we reveal the highly selective generation of p-(N,N-dimethyl)benzyl equivalents from easily-available N,N-dimethyl arylamines via alpha-amino alkyl radicals in the presence of the iridium photosensitizer without any other additives. A series of trifluoromethyl-containing diarylalkanes were obtained in good to high yields from the visible-light-promoted reaction of N,N-dimethyl arylamines and quinols under very mild reaction conditions. The route provides novel access to trifluoromethyl-containing arenes under environment-friendly conditions.