Photocatalyst-Free Regioselective C–H Thiocyanation of 4‑Anilinocoumarins under Visible Light

In the present study, we describe the successful development of a novel and efficient C­(sp2)–H thiocyanation reaction of electron-rich heteroarenes and arenes with readily available ammonium thiocyanate under visible light exposure. Most importantly, the reaction proceeded smoothly without addition of any photocatalyst or strong oxidant, ultimately minimizing the production of chemical waste. The advantages of this reaction met the requirements of green and sustainable synthetic chemistry and may be widely used in organic synthesis and pharmaceutical chemistry.