Trinuclear ruthenium carbonyl

Treatment of (80) and (81) with Ru3(CO)12 gave the >/4-silatrimethylenemethane-ruthenium complexes in 9% and 22% yield, respectively. The major product of the Z-alkylidenesilacyclopropane reaction was trinuclear ruthenium carbonyl cluster (82), whose structure was established by x-ray diffraction (Equation (37)). This appears to be the first example of a main group metal-bound carbonyl inserting into a silacyclopropane <9lJA279i, 94OM4606). 

This observation may well explain the considerable difference between metal-olefin and metal-acetylene chemistry observed for the trinuclear metal carbonyl compounds of this group. As with iron, ruthenium and osmium have an extensive and rich chemistry, with acetylenic complexes involving in many instances polymerization reactions, and, as noted above for both ruthenium and osmium trinuclear carbonyl derivatives, olefin addition normally occurs with interaction at one olefin center. The main metal-ligand framework is often the same for both acetylene and olefin adducts, and differs in that, for the olefin complexes, two metal-hydrogen bonds are formed by transfer of hydrogen from the olefin. The steric requirements of these two edgebridging hydrogen atoms appear to be considerable and may reduce the tendency for the addition of the second olefin molecule to the metal cluster unit and hence restrict the equivalent chemistry to that observed for the acetylene derivatives. 

Grignard additions, 9, 59, 9, 64 indium-mediated allylation, 9, 687 in nickel complexes, 8, 150 ruthenium carbonyl reactions, 7, 142 ruthenium half-sandwiches, 6, 478 and selenium electrophiles, 9, W11 4( > 2 in vanadocene reactions, 5, 39 Nitrites, with trinuclear Os clusters, 6, 733 Nitroalkenes, Grignard additions, 9, 59-60 Nitroarenes, and Grignard reactivity, 9, 70 Nitrobenzenes, reductive aminocarbonylation, 11, 543... 

A very interesting deoxygenation reaction, in which carbon monoxide serves as both, a deoxygenating agent as well as a carbonylating agent, was found recently by Bhaduri et al. The formation of phenyl isocyanate from nitrobenzene with carbon monoxide is catalyzed by trinuclear ruthenium clusters such as Ru3(CO),2 or [HRu3(CO) ] ... 

Known carbonyl hydrides of ruthenium include the unstable HRu(CO)4, as well as the trinuclear H2Ru3(CO)n, tetranuclear H2Ru4(CO)i3 and H4Ru4(CO)i2, and complexes of even higher nuclearity, as well as substitution and deprotonation derivatives. A special feature of ruthenium carbonyl chemistry is the existence of series of carbonyl... 

The chemistry of ruthenium carbonyl clusters is littered with instances where the simple trinuclear cluster acts as a catalyst. The list is lengthened by a study showing direct carbonylation of a C-H bond in a benzene ring of 2-phenyloxazo-lines catalysed by Ru3(CO)i2. 

Au-B bonds are also present in metal clusters with intersticial or peripheral boron atoms. An example is the cluster [Fe4(CO)12BH(AuPPh3)2], which was prepared by reaction of [AuCl(PPh3)] with the carbonyl iron dihydride. With the oxonium salt the reaction proceeds to the trinuclear gold derivative [Fe4(CO)12B(AuPPh3)3] (357).2063-2070 The ruthenium analogues and complexes with other ligands have been also synthesized as, for example, (358).2071-2079... 

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