Organometallic materials surface chemistry

NLO properties, 12, 128 organometallic complexes, 3, 318 as reaction materials, 3, 368 and selenium nucleophiles, 9, 471 surface chemistry on oxides, 12, 502 in triruthenium cyclopentadienyl clusters, 6, 799 trivalent halides, with metal carbonyl monoanions, 3, 347 Group 14 elements... 

Examples given below illustrate synthesis of alkene polymerization catalysts, but these catalysts are simpler than the supported metallocenes used in industry, because they lack the promoter methylaluminoxane (MAO), an ill-defined material that greatly complicates characterization. Other examples given below illustrate (a) details of the surface chemistry of conversion of an organometallic precursor into a supported catalyst (b) synthesis of metal clusters of various sizes and compositions on a family of supports from metal carbonyl precursors and (c) synthesis of supported bimetallic clusters with combinations of noble (e.g., Pt) and oxophilic (e.g., W) metals that give quite stable catalysts with extremely high metal dispersions. 

In this chapter, we present an overview of our experience in the organometallic synthesis of ruthenium nanoparticles of controlled size and surface state. We also give insights on the study of their surface chemistry by using simple techniques, mainly IR and NMR both in solution and in solid state, hi addition, model hydrogenation reactions have been used. We also discuss the performances of these materials as catalysts in solution (organic and aqueous phases) and on a support (alumina, silica, or carbon materials). 

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... 

Based upon analogies between surface and molecular coordination chemistry outlined in Table 1, we have recently set forth to investigate the interaction of surface-active and reversibly electroactive moieties with the noble-metal electrocatalysts Ru, Rh, Pd, Ir, Pt and Au. Our interest in this class of compounds is based on the fact that chemisorption-induced changes in their redox properties yield important information concerning the coordination/organometallic chemistry of the electrode surface. For example, alteration of the reversible redox potential brought about by the chemisorption process is a measure of the surface-complex formation constant of the oxidized state relative to the reduced form such behavior is expected to be dependent upon the electrode material. In this paper, we describe results obtained when iodide, hydroquinone (HQ), 2,5-dihydroxythiophenol (DHT), and 3,6-dihydroxypyridazine (DHPz), all reversibly electroactive... 

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