Visible-light-initiated catalyst-free trifluoromethylselenolation of arylsulfonium salts with [Me4N][SeCF3]

Abstract

The redox potential gap between arylsulfonium salts and [Me₄N][SeCF₃] has been clearly revealed by CV measurements. Construction of the carbon–selenium bond by overcoming this gap without using catalysts and additives is a challenging task. In this work, we reported an efficient visible-light-induced cross-coupling of arylsulfonium triflate with [Me₄N][SeCF₃] by simply mixing these two species, which allowed the facile synthesis of various aryl trifluoromethyl selenoethers under catalyst- and additive-free conditions. The mechanistic study indicated that aryl and ˙SeCF₃ radicals might be formed as key intermediates in the reactions. Merits of the reactions include operational simplicity, high efficiency, visible-light irradiation, good functional group tolerance, a wide range of substrates, excellent chemoselectivity, and good yields of trifluoromethylselenolated products, which combined with a sulfenylation process enabled the selective and practical installation of SeCF₃ moieties onto complex arenes including drug molecules via a formal C–H functionalization.