Hemicelluloses supported palladium/xylan nanocomposites containing N and O ligands: Highly-performance heterogeneous catalysts for Suzuki reaction.

Two kinds of xylan/palladium catalysts (PACMX-Pd and EDAX-Pd) were simply fabricated by integrating two N bidentate ligands into the skeleton of oxygen-rich xylan and followed with the in-situ reduction of palladium. The Pd loading in PACMX-Pd and EDAX-Pd nanocomposites was 0.353 mmol/g and 0.302 mmol/g, respectively. The catalysts exhibited an excellent catalytic activity for the Suzuki reaction with a yield of high up to 100% as well as a superior turnover frequency (TOF: 9626 h-1). Moreover, the catalysts showed outstanding stability and could be reused for at least 5 times without significant decrease in activity. Compared with other polymers and non-polymers supported palladium catalysts, the as-prepared biomass-based catalysts possess potential applications in a wide range of organic catalysis.