Environmentally benign one-pot multicomponent synthesis of 1,4-dihydropyridine derivatives applying montmorillonite K10 as reusable catalyst

Abstract

Environmentally benign one-pot multicomponent synthesis of different 1,4-dihydropyridine derivatives using montmorillonite K10 has been achieved. The montmorillonite K10-catalyzed reaction of aromatic aldehyde, malononitrile, substituted aniline, and diethyl acetylenedicarboxylate in H2O–EtOH allows to obtain structurally diverse 1,4-dihydropyridines in high yields. Possibility to recover and reuse the acidic catalyst in up to five catalytic cycles has been demonstrated. Short reaction times, suppressed formation of side products, inexpensive and nontoxic solvent system, catalyst recovery, and simple workup procedure are the main advantages of the developed synthetic method.