General, Green, and Scalable Synthesis of Imines from Alcohols and Amines by a Mild and Efficient Copper-Catalyzed Aerobic Oxidative Reaction in Open Air at Room Temperature

A general, green, and scalable synthesis of the useful imines and a,beta-unsaturated imines is successfully achieved by a low-loading and powerful, mild and efficient copper-catalyzed aerobic oxidative reaction of alcohols and amines in the open air at room temperature under base- and dehydrating reagent-free conditions. This practical reaction can use air as the economic and green oxidant, tolerates a wide range of substrates, can afford high yields of the target imines on a large scale, and produces water as the only by-product, and thus being the best imination method as yet using alcohols and amines directly.