Carbidocarbonyl clusters structures

An additional significance for carbidocarbonyl clusters has appeared more recently with the discovery of the fascinating reactivity of carbon atoms in clusters when they are exposed to reactive molecules in low nuclearity carbidocarbonyl clusters. These observations followed on the heels of the recognition of the crucial role played by surface bound carbon atoms in metal-catalyzed carbon monoxide hydrogenation, and so a new area of overlap between cluster chemistry and surface chemistry has arisen. Moreover, in this case the comparisons between organometallic and surface chemistry may lie in reactivity and not merely structural similarities. 

Pyrolysis of Et4N[ReH2(CO)4] at 250°C in n-tetradecane yields a mixture of polynuclear products from which two carbidocarbonyl clusters of rhenium have been isolated. Extraction of the pyrolysis product mixture with tetrahydrofuran results in a residue of (E N ReyCfCO iJ, 34 (76), and a solution from which may be isolated (Et4N)2[Re8C(CO)24], 35, (77), the structures of which are shown in Figs. 42 and 43. Both are based on an... 

On the basis of the information described above, some general observations may be made about carbidocarbonyl clusters. The source of the carbon atom, its structural requirements, and its chemical properties are all of interest, as is the effect that it has on the chemistry of the cluster as a whole. 

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