Post-synthetic generation of nanomagnetized tetraaza-copper (II): as a novel heterogeneous catalyst for synthesis of fused N-heterocycles

In this study, we report the synthesis of a novel nanomagnetized [Bis-Schiff base-Cu^(II)] complex through a simple, multi-step post-synthetic modification approach. This method involves the eco-friendly Hugo Schiff-type condensation of o-Phenylenediamine and 4-Hydroxy-2-pyridinecarboxaldehyde-functionalized magnetite nanoparticles and CuCl₂ using a template Schiff base complex synthesis method under mild conditions. The structural characterization of this novel nanomagnetic catalyst is confirmed through various analytical techniques. Catalytic studies demonstrate the remarkable efficiency of the [Fe₃O₄@Bis-Schiff base-Cu^(II)] complex in facilitating the multicomponent synthesis of a diverse range of pyrano[2,3-c]pyrazoles. The experiments were conducted under optimal conditions, resulting in good to excellent yields within a suitable reaction time. Notably, the [Fe₃O₄@Bis-Schiff base-Cu(II)] complex exhibited magnetic recoverability and retained its efficiency even after eight cycles of reuse.