Synthesis of Aryl Tri‐ and Difluoromethyl Thioethers via a CH‐Thiocyanation/Fluoroalkylation Cascade

Abstract An AlCl 3 ‐catalyzed CH thiocyanation was discovered and combined with a Langlois‐type trifluoromethylation to afford aryl trifluoromethyl thioethers directly from arenes, N ‐thiocyanatosuccinimide (NTS) and Ruppert–Prakash reagent. An analogous combination with a copper‐mediated difluoromethylation gives access to aryl difluoromethyl thioethers. Both processes proceed with exceptional regioselectivity for the most electron‐rich, sterically least hindered position of the arene. The sulfur and fluoroalkyl groups originate from different sources, so that the use of expensive, preformed fluoroalkylthiolation reagents is avoided.