Access to divergent benzo-heterocycles via a catalyst-dependent strategy in the controllable cyclization of o-alkynyl-N-methoxyl-benzamides

A chemo- and regio-selectively controllable approach for construction of diverse benzo-heterocycles is established. A new strategy for using the ligand effect in gold catalysis to control the regioselectivity in the cyclization of o-alkynyl-N-methoxyl-benzamide is successfully achieved. Meanwhile, the chemoselectivity between nitrogen and oxygen nucleophiles is precisely switched by gold and platinum catalysts.