Organometallic Complex of Palladium on Boehmite Nanoparticles as Highly Efficient and Organic-Inorganic Hybrid Nanocatalyst for the C-C Coupling Reactions

Boehmite is a cubic orthorhombic structure of aluminum oxide hydroxide which was prepared through addition of NaOH solution to Al(NO3)3.9H2O solution at room temperature. In this work, the surface of boehmite nanoparticles (BNPs) was modified by 3-choloropropyltrimtoxysilane (CPTMS) and further 1-methyl imidazole was anchored on its surface. Finally, an organometallic complex of palladium was supported on the surface of modified BNPs (Pd-imi@BNPs). These obtained nanoparticles were applied as efficient, recyclable and hybrid of organic-inorganic nanocatalyst in carbon-carbon coupling reactions under phosphine-free conditions at atmospheric pressure. Structure of this catalyst was characterized by SEM, TGA, XRD and ICP techniques. Heterogeneity and stability of Pd-imi@BNPs were studied by poisoning test and AAS technique which palladium leaching was not observed in reaction conditions. Therefore, this heterogeneous catalyst can be reused for several times. Also, all products were obtained in high TON and TOF numbers in the presence of Pd-imi@BNPs, which are reveal the high efficiency of this catalyst in C-C coupling reactions. Selectivity of this catalyst was studied in various aryl halides which are bearing different functional groups.

Keywords:

Boehmite nanoparticles , Suzuki–Miyaura reaction , Mizoroki-Heck reaction , Palladium , C-C coupling reactions