The convenient synthesis and reaction of 2-(arylthio)phenols under ligand-free conditions: arylthioquinone preparation through cascade C–H functionalization and oxidation from arylthiols and aryl iodides

An convenient and simple method for copper-catalyzed synthesis of 2-(arylthio)phenols through C–H functionalization of arylthiols and aryl iodides was developed under ligand-free conditions without nitrogen protection. In addition, arylthioquinone derivatives were very easily prepared for one more step of oxidation with moderate to good yields. This provides an alternative and efficient way to 2-(arylthio)phenols and arylthioquinone derivatives smoothly without using ligands and nitrogen protection or expensive arylboronic acids.