Tandem imine formation via auto-hydrogen transfer from alcohols to nitro compounds catalyzed by a nanomagnetically recyclable copper catalyst under solvent-free conditions

Abstract

A direct imination reaction was developed by tandem reaction of alcohols and nitro compounds in the presence of Cu-isatin Schiff base-γ-Fe₂O₃ as a nanomagnetically recyclable catalyst under solvent-free conditions. By this method, various imines were prepared in good to high yields from one-pot reaction of various alcohols (primary aromatic and aliphatic) and nitro compounds (aromatic and aliphatic) via an auto-hydrogen transfer reaction. Use of an inexpensive and easily reusable catalyst, without requiring any additives or excess amounts of benzyl alcohol as the reaction solvent are the other advantages of this method. This catalytic system has the merits of cost effectiveness, environmental benignity, excellent recyclability and good reproducibility.