Mild ligand-free Cu0-catalyzed chemoselective S-arylation of 2-mercaptoimidazole at low catalyst loading

A mild method for the Cu0-catalyzed chemoselective CS cross-coupling of 2-mercaptoimidazole derivatives with a series of with differently substituted iodobenzenes and iodothiophenes at 100 °C is described. This method proceeds efficiently without ligands and at low catalyst loading (3 mol %), without the need for stringent inert conditions. Under optimized conditions, the S-arylated products were obtained in good yields of up to 90%.