Microwave-assisted oxidative coupling of amines to imines on solid acid catalysts

A K-10 montmorillonite catalyzed microwave-assisted oxidative coupling of amines is described. Substituted benzylamines readily undergo self-coupling reactions to produce benzylidene–benzylamines, while aliphatic amines and anilines cannot form self-coupled products. A mixture of a benzylamine and an aniline or aliphatic amine, respectively, effectively, and selectively produces mixed imines, such as benzylidene–anilines and benzylidene–alkylamines.