We have developed siliceous mesocellular foam (MCF) as a facile and versatile support material for heterogenized catalysis. This material is attractive for its robust, well-defined pore structure with interconnected, ultralarge pores that facilitate diffusion. Catalytic complexes are successfully immobilized on MCF, and easily recycled. By tuning the property of the linker groups and the microenvironment, these heterogenized catalysts were effectively applied towards useful reactions such as ring-closing metathesis (RCM) and asymmetric cyclopropanation. A circulating flow-type reactor has also been developed to circumvent the gaseous byproducts in packed bed reactors for large-scale reaction. Excellent activity and extremely low level of metal leaching were attained with these robust catalysts. These heterogenized catalysts and reactor scheme would facilitate the development of environmentally friendly and more cost-efficient industrial processes.

The 12th Annual Green Chemistry & Engineering Conference, Washington, DC, June 24-26, 2008.