Imidazolium organometallic complex of palladium on Fe3O4 nanoparticles as selective and magnetically recoverable nanocatalyst for C-C cross-coupling reactions

The synthesis of an efficient heterogeneous nanocatalyst was prepared by the anchoring of palladium complex on the surface of an imidazolium-based ionic liquid-functionalized Fe3O4 (Pd-imidazolium@Fe3O4 NPs). The nanocatalyst, Pd-imidazolium@Fe3O4 NPs, was characterized by Raman, X-ray diffraction (XRD), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), fourier transform infrared (FT-IR), inductively coupled plasma (ICP), and vibrating sample magnetometer (VSM) techniques. The catalytic performance of this novel nanocatalyst was evaluated in the Heck--Mizoroki and Suzuki-Miyaura cross-coupling reactions under mild conditions using PEG-400 as a green and biodegradable solvent. The nanocatalyst exhibited high catalytic activity for both cross-coupling reactions. Furthermore, this stable nanocatalyst can be easily removed and recovered from the reaction mixture and reused for at least eight consecutive cycles without a discernible decrease in the catalytic activity. Also, the recovered Pd-imidazolium@Fe3O4 NPs was characterized by FT-IR, XRD, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and atomic absorption spectroscopy techniques.