Modified mesoporous materials as Pd scavengers and catalyst supports

The use of mesoporous molecular sieves (MMSs) modified by mercaptopropyl trimethoxysilane (MPTMS) to scavenge Pd is described. The ordered mesoporous material displays excellent ability to remove Pd from organic and aqueous solutions. After only one treatment, a 500-ppm solution of PdCl in water can be reduced to 1 ppb. In addition, the resulting material is an effective, leach-proof catalyst for the Suzuki-Miyaura and Mizoroki-Heck reactions. Thus, the Suzuki-Miyaura reaction can be conducted in water at 80 °C with as little as 3 ppb Pd leaching. Hot filtrations and three-phase tests confirm that the catalyst acts without leaching Pd from the surface.