Ce immobilized 1H-pyrazole-3,5-dicarboxylic acid (PDA) modified CoFe2O4 : A potential magnetic nanocomposite catalyst towards the synthesis of diverse benzo[a]pyrano[2,3-c]phenazine derivatives

A great deal of modern material research involves the design and synthesis of biomolecular functionalized green catalysts. In this context, we have engineered a novel nanocomposite material by functionalizing H-1-pyrazole-3,5-dicarboxylic acid ligand over CoFe2O4 NPs and subsequently immobilized Ce ions over it. The ligand anchors the metal ion in 1:2 fashion through its two carboxylic acid functions. The as synthesized material was meticulously characterized by using a wide range of physicochemical techniques like FT-IR, VSM, SEM, TEM, EDX, elemental mapping, XRD, TGA, N-2 adsorption-desorption and BET surface area analysis. The nanocomposite was catalytically explored in the synthesis of an array of biologically important benzo[a]pyrano[2,3-c]phenazine derivatives by condensing 2-hydroxynaphthalene-1,4-dione, ophenylenediamines, malononitrile and different aryl aldehydes under green conditions. A diverse range of products was synthesized with outstandingyields in short reaction times. Due to inherent magnetism, the catalyst was recovered from the reaction magnetic decantation and recycled for six consecutive runs with a nominal decrease in yield. (C) 2021 Elsevier B.V. All rights reserved.