Introducing a CoFe₂O₄@CS-BAPT/Cu^II nanocomposite as an efficient catalyst for the synthesis of 4H-pyran derivatives

This study introduces the development of an innovative and environmentally friendly bio-nanocatalyst (CoFe₂O₄@CS-BAPT/Cu^II nanocomposite), designed and employed for three-component synthesis of 2-amino-3-cyano-4H-pyrans. Chitosan (CS) as a biodegradable polymer was functionalized with bis(2-aminopyridine)triazine (BAPT) moieties. Subsequently, CoFe₂O₄ magnetic nanoparticles (MNPs) were incorporated and copper ions were immobilized on the composite to form the final magnetic nanocomposite (CoFe₂O₄@CS-BAPT/Cu^II). Characterization techniques such as Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray (EDX) analysis, vibrating sample magnetometry (VSM), inductively coupled plasma atomic emission spectroscopy (ICP-OES), dynamic light scattering (DLS), and zeta potential were used to analyze the nanocomposite structure. XRD analysis showed a near-amorphous structure after functionalizing CoFe₂O₄ with chitosan. FE-SEM images revealed uniform particles without aggregation, with an average size of 12-14 nm. TGA indicated thermal stability up to 300 °C. CoFe₂O₄@CS-BAPT/Cu^II was successfully used in the green synthesis of 2-amino-3-cyano-4H-pyrans with potential biological properties. The desired products were synthesized with high yields (83-95%) in short reaction times (20-45 minutes). Furthermore, the catalyst exhibited easy magnetic separation and good reusability, highlighting its potential as an efficient and sustainable heterogeneous catalyst. Key advantages of this approach include the use of an easily accessible bio-polymer, environmentally friendly catalytic protocols, a simplified and cost-effective synthesis process, clean reactions that generate no additional waste, and the reusable nature of the catalyst.