Heterocycle compounds synthesized by amide ligand-promoted copper salt catalyzed construction of C-O(S) bonds

We introduce a mild method for the ligand-promoted copper-catalyzed coupling of 2-halophenol to construct DBDO using cost-effective copper salts, ligands, and alkaline reagents. This method cleverly makes 2-bromophenol complete the Ullman reaction twice, achieves efficient C-O(S) bond coupling and intermolecular cyclization, and yields high amounts of oxygen(sulfur)-containing six-membered ring products. Less reactive 2-chlorophenol was also applied in this catalytic system. The application range of the copper-amide catalytic system was further expanded. Moreover, the success of a gram-scale reaction demonstrated that this operationally simple process is scalable.