Gold-Catalyzed Intermolecular 1,2-Difunctionalization of Alkynes with Aryl Iodides

Compared with traditional transition metals, gold-catalyzed 1,2-difunctionalization of C–C multiple bonds has introduced a new paradigm. Herein, we report an unexplored gold-catalyzed intermolecular 1,2-difunctionalization of alkynes with aryl iodides in an EtOH/H2O mixture, furnishing a variety of α-aryl ketones, overcoming challenges such as facile hydrofunctionalization and direct cross-coupling. Under the influence of the hemilabile MeDalphos ligand gold catalyst, various alkynes underwent 1,2-difunctionalization with different aryl iodides, achieving a high efficiency and good regioselectivity to form α-aryl ketones in a one-pot reaction. This approach eliminates the need for strong external oxidants and the photocatalytic activation of aryl diazonium salts. Mechanistic and theoretical studies support a reaction pathway that effectively integrates the oxidative addition of aryl iodides and the π-activation of alkynes in gold(I)/gold(III) catalysis.