CuFe2O4 nanoparticles via thermal decomposition as recyclable magnetic catalysts for perimidine synthesis

Spinel ferrites represent a versatile class of compounds extensively utilized across various applications, particularly valued for their distinctive magnetic properties. Beyond their conventional uses, these materials have emerged as effective magnetic catalysts in organic synthesis for the production of diverse molecular structures. Herein, an alternative synthetic pathway is presented for obtaining CuFe₂O₄ through the thermal decomposition of Cu^{+ 2} and Fe^{+ 3} chelates, employing 8-hydroxyquinoline (8-HQ) as the coordinating ligand. The chelates were characterized by XRD, FTIR, XRF and SEM/EDS. A systematic study of their thermal decomposition was conducted by TGA, DTG, and DTA, under both oxygen and nitrogen atmospheres, varying the heating rate. Subsequently, the chelates were calcinated at different temperatures (750, 850, 950, and 1050 °C), yielding CuFe₂O₄ in powder form. The resulting CuFe₂O₄ was further characterized by XRD, SEM, TEM, and VSM analysis. The synthesized CuFe₂O₄ nanoparticles demonstrated excellent catalytic performance in the condensation reaction between 1,8-diaminonaphthalene and various aldehydes, producing a series of 2-substituted 2,3-dihydro-1H-perimidines in excellent yields. Finally, the CuFe₂O₄ nanoparticles were successfully recovered magnetically and efficiently employed in gram-scale reactions, demonstrating their practical recyclability.