Carbonyl clusters compounds

Metal-metal bond bond order k (mdyn A ) fo(A) 

Peter ComDa, Trevor W. HamWey copyright VCH Vertagsgesellschaft nibH, 1995 

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Novel reactions of metal carbonyl cluster compounds, R. D. Adams and 1. T. Horvarth, Prog. Inorg. Chem., 1985, 33,127 (200). 

Phosphine palladium and phosphine platinum carbonyl cluster compounds. N. K. Eremenko, E. G. Mednikov and S. S. Kurasov, Russ. Chem. Rev. (Engl Transl.), 1985, 54, 394 (69). 

The idea (50, 5/) of dual coordination of CO implies the presence of two coordination centers in a Fischer-Tropsch catalyst system, i.e., a carbonyl carbon coordinating center, Ma, and a carbonyl oxygen coordinating center, M6 (14). It is this concept which has led at least two groups to examine transition metal carbonyl cluster compounds as homogeneous Fischer-Tropsch catalysts. 

Even though qualitative bonding descriptions of metal atom clusters up to six or seven atoms can be derived and in some cases correlated with structural detail, it is clear that most structures observed for higher clusters cannot be treated thus. Nor do the structures observed correlate with those observed for borane derivatives with the same number of vertices. Much of borane chemistry is dominated by the tendency to form structures derived from the icosahedron found in elemental boron. However, elemental transition metals possess either a close-packed or body-centered cubic arrangement. In this connection, one can find the vast majority of metal polyhedra in carbonyl cluster compounds within close-packed geometries, particularly hexagonal close-packing. 

The formation of carbido-carbonyl cluster compounds with ruthenium and osmium appears to be common in pyrolysis reactions the basic reaction may be viewed as the transformation of the coordinated carbon monoxide to carbide and carbon dioxide. Small variations in... 

The role of bridging groups in metal carbonyl cluster compounds is still not completely understood but has been discussed qualitatively by... 

High Nuclearity Carbonyl Cluster Compounds of Osmium 295... 

HIGH NUCLEARITY CARBONYL CLUSTER COMPOUNDS OF OSMIUM... 

Chemical Properties. When subjected to UV irradiation5 or temperatures > 150°C,7 compound 1 eliminates 1 mol of benzene and is transformed into a variety of new thioosmium carbonyl cluster compounds. 

Metal carbonyl cluster compounds which contain three ruthenium or three osmium atoms in the cluster core are common.1 Potentially useful reagents for syntheses of these compounds are the triruthenium and triosmium dianions [M3(CO)h]2 (M = Ru, Os).2 Therefore, it is desirable to develop good synthetic routes to obtain [M3(CO)11]2- (M = Ru, Os) of high purity in high yields. A method that is particularly useful for generating [M3(CO)n]2 (M = Ru, Os) is the designed stoichiometric reduction of M3(CO)12 (M = Ru, Os) using an electron carrier such as potassium-benzophenone.3... 

K. Wade, The Structural Significance of the Number of Skeletal Bonding Electron-pairs in Carboranes, the Higher Borane Anions, and Various Transition-metal Carbonyl Cluster Compounds, Chem. Comm. 1971, 792-793. 

Tri-/i-carbonyl-nonacarbonyltetrarhodium is the starting material for the synthesis of a large number of rhodium carbonyl cluster compounds.10... 

This anion provides both the first example of a trigonal prismatic hexanuclear cluster and one of the more easily prepared carbido-carbonyl cluster compounds. 

Apart from hydridoruthenium carbonyl cluster compounds (see Sections 45.10.3.3 and 45.10.4) the only Ru° hydride complexes are the deep brown [RuH(NO)(PR3)3] (R3 = Ph3, Ph2Me, Ph2Pr , Ph2Cy) w hich are fully discussed in Section 45.5.1.2. 

Because of the great strength of iridium-iridium bonds, there is a wealth of information on polynuclear metal-carbonyl cluster compounds of iridium (see Dinuclear Organometallic Cluster Complexes mA Polynuclear Organometallic Cluster Complexes). It4(CO)i2 (45) may be synthesized from... 

The structures of several carbonyl cluster compounds were shown in Chapter 13. Many carbonyl clusters have stmctures similar to boranes it is therefore of interest to determine to what extent the approach used to describe bonding in boranes may also be applicable to bonding in carbonyl clusters and other clusters. 

Fig. 23. Correlation between rates of product formation in the CO + Hj reaction and Ir/Fe atomic ratios of catalysts prepared from Si02-supported IrFe bimetallic carbonyl cluster compounds.

Adams, Richard D. and Horvath, Istvdn T., Novel Reactions of Metal Carbonyl Cluster Compounds. 33 127... 

As the development of suitable cobalt hydroformylation catalysts occurred, work was also carried out to create corresponding Rh complexes that could also serve as suitable catalysts. Under appropriate conditions in the presence of H2 and CO, HRh(CO)4 forms from Rh-carbonyl cluster compounds. The hydrido-Rh... 

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