Surface organometallic chemistry

Solid catalysts are macroscopic objects, but catalysis itself is primarily a molecular phenomenon. This means that many of the principles of homogeneous complexes apply to active sites. Conceptually, we can consider the support as a very large and rigid ligand, especially when the active site itself is an organometallic species which is anchored on the support. Indeed, experiments show that functional groups on surfaces exhibit chemical properties which are similar to their liquid-phase counterparts. 

Naturally, SOMC depends on a good characterization and understanding of the solid support structure [125]. Silica is one of the most commonly used supports in SOMC studies, owing to its relatively simple and controllable structure [126]. The 

Liquid/Solid and Liquid/Liquid Catalytic Systems 

Liquid/solid and liquid/liquid systems are important, because most of the chemicals we use are either liquids themselves at ambient temperature, or are dissolved in a liquid. These catalytic systems are gaining ground, as industrial attention turns to 

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Metal particles Oxide supports Surface organometallic chemistry... 

In this review, we will specifically discuss the similarities and the differences between the chemistry on surfaces and molecular chemistry. In Sect. 2, we will first describe how to generate well-dispersed monoatomic transition metal systems on oxide supports and understand their reactivity. Then, the chemistry of metal surfaces, their modification and the impact on their reactivity will be discussed in Sect. 3. Finally, in Sect. 4, molecular chemistry and surface organometallic chemistry will be compared. 

Structural Similarities and Differences between Molecular and Surface Organometallic Chemistry... 

It is first necessary to distinguish the surface organometallic chemistry on metals and on oxides since one deals with a large ensemble of metals, while the others generate dispersed metal atoms attached covalently onto the support. 

Metalloporphyrinosilicas as a new class of hybrid organic-inorganic materials were prepared by polymerization of 3- er -butyl-5-vinylsalicylaldehyde with styrene and divinylbenzene and used as selective biomimetic oxidation catalyst.27 Synthesis and structural characterization of rare-earth bisfdimethyl-silyl)amides and their surface organometallic chemistry on mesoporous silicate MCM-41 have been reported.28... 

The reaction of organometallics with metal surfaces is a very promising aspect of surface organometallic chemistry related to fine chemicals. The precise understanding of the reactions between organometallics and metal surfaces is essential to obtain highly selective catalysts by this route.292,293... 

Surface Organometallic Chemistry as a Tool for Tailor-Made Catalysts... 

Surface Organometallic Chemistry for Study of the Elementary Steps in Heterogeneous Catalysis... 

Basset, J. M., Gates, B. C., Candy, J. P., Choplin, A., Leconte, M., Quignard, E, and Santini, C. C., Surface Organometallic Chemistry Molecular Approaches to Surface Catalysis, NATO ASI Series, Kluwer, Dordrecht, 1988. 

In contrast to supported homogeneous catalysis, surface organometallic chemistry (SOMC) uses an inorganic oxide (ExOy) as a solid ligand, on which the metal is directly attached by at least a bond with a surface atom, usually an oxygen, through a M-OE bond. 

Heterogeneous Catalysts Prepared via Surface Organometallic Chemistry 142 6.7 Conclusions 145... 

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