New and efficient heterogeneous catalytic system for Heck reaction: Palladium colloid layer in situ reduced in the channel of mesoporous silica materials

The synthesis and characterization of palladium colloid layer grafted mesoporous SBA-15 material, designated as Pd-SBA, are described. In the preparation of this new catalyst, the Si-H functional groups were introduced into the channel of SBA-15 mesoporous materials resulting in highly dispersed metal colloid layer on the pore walls of the supporting material. The material is investigated for Heck coupling reactions with activated and non-activated aryl substrates. The ultrahigh specific area, large pore opening, and highly dispersed catalyst species in Pd-SBA material create one of the most active heterogeneous catalysts for Heck coupling reactions.