An Efficient Synthesis of Dihydropyrano[3,2-c]chromene and Biscoumarin Derivatives Catalyzed by Ionic Liquid Immobilized on FeNi₃ Nanocatalyst

In this research, a highly efficient method is described for the synthesis of dihydropyrano[3,2-c]chromenes and biscoumarins using ionic liquids (ILs) supported on nano-FeNi₃ as catalyst. The heterogeneous catalyst was fully characterized by X-ray diffraction (XRD), SEM, FT-IR, and vibrating sample magnetometer (VSM).