Rationally designed Cu(ii) Schiff base metal complex anchored on NiFe2O4@chitosan: an efficient heterogeneous and magnetically retrievable hybrid nanocatalyst for the one-pot multi-component synthesis of bioactive 1-amidoalkyl-2-naphthols†

Abstract

We reported, herein, the fabrication of a Cu(II) Schiff base metal complex, immobilized on chitosan surface coated on NiFe₂O₄ MNPs, intended as a novel heterogeneous and magnetically recyclable nanocatalyst, NiFe₂O₄@CS@CuSB. The synthesis process starts with the preparation of NiFe₂O₄ MNPs followed by coating with chitosan and then subsequent immobilization of the Cu(II) Schiff base metal complex on its surface. Through comprehensive characterization of the prepared nanocatalyst using FT-IR, PXRD, SEM, EDS, TEM, SAED, VSM, BET, XPS, and ICP-AES, the structure, surface morphology, elemental composition, and characteristics of the catalyst are revealed. For the evaluation of its catalytic activity, NiFe₂O₄@CS@CuSB, has been utilized as a potential nanocatalyst for the one-pot multicomponent organic synthesis of 1-amidoalkyl-2-naphthol scaffolds. A straightforward, effective, one-pot, and environmentally safe synthesis of 1-amidoalkyl-2-naphthol has been accomplished using a broad range of aldehydes, 2-naphthol, urea, or amide, demonstrating the catalyst's strong resistance to different functionalities. High yields of the intended products have been obtained without the formation of byproducts. A hot filtration test was employed to evaluate the heterogeneity of the solid nanocatalyst. With potential uses in medicinal chemistry, this novel catalyst presents a viable method for the effective production of bioactive molecules.