Heterogeneous bimetallic ZnFe2O4 nanopowder catalyzed synthesis of Hantzsch 1,4-dihydropyridines in water

The mixed metal oxide ZnFe2O4 nanopowder, a dual Lewis acid-base combined catalyst is found to efficiently catalyze a multicomponent synthesis of 1,4-dihydropyridines from aldehydes, ethyl acetoacetate, and ammonium acetate in water. This procedure offers several advantages including high yields, short reaction times, a simple work-up procedure, and a benign eco-footprint. This method takes advantage of the fact that water, a green solvent is used in combination with ZnFe2O4 nanoparticles as catalyst which can be easily recovered magnetically and reused for further runs. (C) 2016 Elsevier Ltd. All rights reserved.