Recent research has been focused on the transition metal-catalyzed reactions. Herein we have developed nickel-catalyzed synthesis of 3-aryl benzofurans fromortho-alkenyl phenolsviaintramolecular dehydrogenative coupling. Notably, simple O2gas served as an oxidant, without using any sacrificial hydrogen acceptor. The strategy enabled the synthesis of 3-aryl benzofurans in good to excellent yields. © The Royal Society of Chemistry 2020.