The unique structure of MCM‐41 silicates (shown in the picture) has provided for extremely attractive properties—uniform pore sizes greater than 20 Å, surface areas exceeding 1000 m2 g−1, and long‐range ordering of the pores. Recent research in supramolecular‐templated mesoporous materials has led to a wide range of compositions, to uses in a variety of catalytic reactions, and to a better control of bulk morphologies.

The new concept of supported ionic liquid catalysis involves the surface of a support material that is modified with a monolayer of covalently attached ionic liquid fragments. Treatment of this surface with additional ionic liquid results in the formation of a multiple layer of free ionic liquid on the support. These layers serve as the reaction phase in which a homogeneous hydroformylation catalyst was dissolved. Supported ionic liquid catalysis combines the advantages of ionic liquid media with solid support materials which enables the application of fixed-bed technology and the usage of significantly reduced amounts of the ionic liquid. The concept of supported ionic liquid catalysis has successfully been used for hydroformylation reactions and can be further expanded into other areas of catalysis.

Supported ionic liquid catalysis is a concept which combines the advantages of ionic liquids with those of heterogeneous support materials. The viability of this concept has been confirmed by several studies which have successfully confined various ionic phases to the surface of support materials and explored their potential catalytic applications. Although the majority of the evaluated supports were silica based, several studies focused on polymeric materials including membranes. The preparation of these materials was achieved by using two different immobilization approaches. The first approach involves the covalent attachment of ionic liquids to the support surface whereas the second simply deposits the ionic liquid phases containing catalytically active species on the surface of the support. Herein recent advances made in this area are described.

The synthesis and characterization of palladium-grafted mesoporous MCM-41 material, designated Pd-TMS11, are described. The material is investigated for carbon−carbon coupling reactions (Heck catalysis) with activated and nonactivated aryl substrates. For the preparation of the new catalyst, a volatile organometallic precursor is reacted in the gas phase with the surface of the porous framework, generating a highly dispersed metal deposition. The ultrahigh surface area, the large pore opening, and the highly dispersed catalyst species in Pd-TMS11 material create one of the most active heterogeneous catalysts for Heck reactions.

The concept of supported ionic liquid catalysis (silc) has successfully been applied to hydrogenation reactions, which significantly reduced the required amounts of ionic liquid phase and enabled the usage of fixed-bed technology; the resulting catalysts exhibited high activity and outstanding stability.

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