Efficient ligand-free copper-catalyzed C–S cross-coupling of thiols with aryl iodides using KF/Al2O3 as base

We report a mild, convenient, environmentally friendly, and ligand-free synthetic protocol for the cross-coupling reaction of aryl iodides and thiols using 10 mol % CuI with KF/Al2O3 as the base, in DMF at 110 °C. Using this protocol, we have shown that a variety of aryl sulfides can be synthesized in excellent yields from readily available iodides and thiols.