An efficient chitosan-derived carbon/silica microspheres supported Pd catalyst with high stability for Heck reactions

To maintain stability and activity in Heck-coupling reaction, a novel composite carrier with controllable uniform size, high complex ability and mechanical intensity was fabricated in microchannel using natural N-doped biomolecule chitosan and silica as ingredients. Post carbonization increased its thermal stability and supported Pd@C/silica catalysts can be acquired after Pd loading. Only 2 mg supported Pd@C/silica catalysts (0.44 μmol) can achieve high yield (>95%) in a typical Heck-coupling reaction and maintained activity even after 8 times of recycling. This type of novel porous microspheres carrier can cut down the usage of noble Pd by avoiding the leaching as well as aggregation of Pd nanoparticles, and could be widely applied in similar chemical reactions.