Copper-catalyzed aerobic oxidative cross-dehydrogenative coupling of amine and α-carbonyl aldehyde: a practical and efficient approach to α-ketoamides with wide substrate scope.

A copper-catalyzed aerobic oxidative cross-dehydrogenative coupling (CDC) of amine with α-carbonyl aldehyde has been developed. Many types of amines are tolerant in this transformation leading to various α-ketoamides compounds. Wide substrate scope, CDC strategy and using air as oxidant make this transformation highly efficient and practical. Molecular oxygen acts not only as the oxidant, but also as an initiator to trigger this catalytic process. Furthermore, mechanism studies show that carbonyl group of α-carbonyl aldehyde plays a role as the directing group to facilitate this chemical process.