Synthesis of a new Pd(0)-complex supported on boehmite nanoparticles and study of its catalytic activity for Suzuki and Heck reactions in H2O or PEG

Abstract

Boehmite nanoparticles are a cubic orthorhombic structure of aluminum oxide hydroxide containing hydroxyl groups attached to their surface, which were prepared in water using commercially available materials. A moisture- and air-stable palladium S-methylisothiourea complex supported on boehmite nanoparticles (Pd(0)–SMTU–boehmite) was prepared using a very simple and inexpensive procedure without an inert atmosphere using commercially available materials. This nanostructure compound was used as an excellent organometallic catalyst for Suzuki and Heck reactions in H₂O or PEG-400. The synthesized nanoparticles were characterized using FT-IR, XRD, BET, TGA, TEM, SEM, EDS and ICP-OES techniques. Nitrogen adsorption/desorption measurements indicated that the boehmite nanoparticles have a BET surface area of about 122.8 m² g⁻¹. This heterogeneous nanocatalyst was easily separated from the reaction mixture and reused for several consecutive runs without significant loss of its catalytic efficiency or palladium leaching. The leaching of palladium from the catalyst was examined using hot filtration and ICP-OES techniques.