Phosphine-stabilized Pd nanoparticles supported on silica as a highly active catalyst for the Suzuki-Miyaura cross-coupling reaction

摘要

We have prepared a silica supported palladium nanocatalyst (PdNP@PPh2-SiO2) with high dispersion via a one-step reaction between commercially available 2-diphenylphosphinoethyl-functionalized silica gel (PPh2-SiO2) and PdCl2 without the assistance of an external reductant or stabilizer. The catalyst was well characterized by N-2-adsorption, XRD, HRTEM, SEM-EDX and ICP analyses. The supported catalyst exhibited excellent activity for the Suzuki-Miyaura cross-coupling reactions of aryl halides (including aryl chlorides) with arylboronic acids. The facile synthesis of the catalyst combined with high product yields at relatively low catalyst loading (<0.5 mol%) represents one of the most efficient silica supported heterogeneous systems for the Suzuki coupling of aryl chlorides. The catalyst could be reused several times without compromising its activity.