Osmium carbonyls

The Ti coordination via the carbocycle prevails for indole and carbazole, although the species were also found in organomanganese and -iridium chemistry. Osmium carbonyls tend to produce the species with the bridging indole function. Some illustrations of the ti N) coordination exist. 

Osmium carbonyl (Os3(CO)i2) acts as a photoinitiator of vinyl polymerization [20], which can function without a halide additive. The mechanism of photoinitiation is by a hydrogen abstraction from monomer to pho-... 

Advances in platinum metal carbonyls and their substituted derivatives, I. Ruthenium and osmium carbonyls. S. C. Tripathi, S. C. Srivastava, R. P. Mani and A. K. Shrimal, Inorg. Chim. Acta, 1975, 15,249-290 (327). 

This proton transfer reaction is not fast, and it is suggested that this may be a more complicated reaction than was anticipated, perhaps occurring by initial addition of OH or OR to the metal followed by H2O or ROH expulsion. In support of this is the isolation of a complex Os(CO)-(CNC6H4CH3)(PPh3)2(H)OR from an analogous reaction sequence. (This is the only reference yet to any osmium carbonyl-isocyanide chemistry.)... 

Fig.1 Surface-mediated synthesis of osmium carbonyl clusters on the surface of MgO...

Fig.2 High-resolution transmission electron micrograph of [Os5C(CO)i4] on MgO. This cluster was present with osmium carbonyl clusters with lower nuclearities (containing three and four Os atoms) [25]...

Sections 8.3.1-8.3.3 present the use of iron, mthenium and osmium carbonyls, respectively, in the preparation of supported catalysts. Over non-inert supports, besides the characteristics of carbonyl compounds, the reactivity of the surface and that of the specific element, mainly related with its redox properties, will be covered for each metal. 

The best syntheses of neutral osmium carbonyl compounds mediated by the surface of Si02, summarized in Scheme 16.5, are described below. 

Scheme 16.6 Convenient syntheses of anionic osmium carbonyl compounds on the surface of Si02.

Scheme 16.7 Convenient syntheses of osmium carbonyl compounds on the surface of MgO AI2O3, ZnO, or La203, (the subscript x refers to the pretreatment temperature, in °C).

Nucleation of Os(ll) Carbonyl Species to Various Osmium Carbonyl Clusters... 

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