Dinuclear complexes osmium

Dinuclear clusters ferrous site distortion, 38 175 spin ladder, 38 182-183 Dinuclear cobalt complex, 45 291-293 Dinuclear complexes osmium, electrochemistry, 37 321-323 quadruply bridged, 40 187-235 axial ligand substitution properties, 40 232-234... 

Bullitt, J. G. Cotton, F. A. (1971) The structure of a dinuclear complex of osmium(I) with a metal-to-metal single bond bis-(/i-acetatojhexacarbonyldiosmium, Inorg. Chim. Acta. 5, 406-412. 

Ru3(CO)10(Ph2C2)2, and Ru3(CO)9(C2(Ph)2)3 (128). The dinuclear complex Ru2(CO)6(C2Ph2)2, containing a metallocyclopentadiene ring similar to that observed for both iron and osmium, is a further product in the reaction this does imply very similar structures for the trinuclear adducts to those observed for iron and osmium. The carbonyl reacts with tetracyclone to yield the complex Ru3(CO)i0(C2Ph2)2, which may be related to the osmium compounds discussed later. Phosphine substitution of the carbonyls in some of these compounds has been established. 

Because these ligands coordinate through oxygen atoms, they stabilize high as well as low oxidation states. Two representative Mo(II) and W(II) dinuclear complexes are given in equation (2.65). The 18e osmium complexes may serve as 2e ligands, which may coordinate to other metals, such as (Me3P)(OC)4 OsW(CO)s. There is a donor-acceptor Os —W bond in this compound. In the solid state... 

The structurally characterized octahedral tetracarbonyl complex m-[Os(GO)4(FSbF5)2] 3 is formed upon fluorination of [OS3GO12] with HF/SbFs. The oxidative fluorination of [M3(GO)i2] with XeF2 in anhydrous HF provides a route to m-[M(GO)4F2] (M = Ru 4a, Os 4b). Both the ruthenium and osmium complexes were characterized by multi-nuclear NMR spectroscopy, along with [M(GO)sF] (M = Ru 5a, Os 5b), mer- and < -[Ru(GO)3F3] 6 and 7, and a range of dinuclear complexes, which were formed as minor products. Removal of the HF solvent in vacuo results in conversion of [M(GO)4F2] to the tetrameric species [ Os(GO)3F2 4]- ... 

A similar range of reactions has also been reported for the ruthenium carbonyl-triphenylphosphine systems (148). In these systems, a high percentage of the products were dinuclear, reflecting the weaker bonding in the ruthenium system, and as for some of the osmium complexes discussed above, some contain orthometallated phenylphos-phine groups (see Fig. 29, structures I, IV, X). 

Linkage isomerizations, osmium, 37 335-339 Linked cubane clusters, Fe—S proteins, biological implications, 38 55-56 Linked macrocyclic ring systems, 45 75 dinuclear systems, 45 89-95 triaza ring systems, 45 76-87 Li—N—Li linkages, 37 100-101 Lipoxygenase, inhibitors, 36 41 Liquid-liquid extraction of metal ions, 9 1-80 with acidic P-based extractants, 9 34-48 with acidic P-based extractants dinuclear, 9 47-48 mononuclear, 9 34-47 with amines and amine oxides, 9 49-56 complexes in, 9 68-71 countercurrent extraction method, 9 15-25... 

Eliminations from Os(CO)4RR occur by dinuclear mechanisms only if either R or R is H. A hydride on one metal is necessary to interact with a vacant coordination site on the other in the dinuclear transition state. With Os(CO)4H2, the vacant site is created by dissociation of CO. With Os(CO)4-(H)CH the vacant site is created by a facile rate-determining isomerization which we suggest is to an acetyl hydride. The unique instability of hydridoalkyl carbonyls thus is explained. The synthesis and properties of Os(CO)4(H)C2H and various polynuclear ethyl osmium derivatives show that (3-hydrogens have no significant effect on these elimination mechanisms. Dinuclear hydridoalkyls are excellent starting points for the synthesis of more complex polynuclear alkyls. 

Comparison of Redox Potentials and Comproportionation Constants for Symmetrically Substituted Dinuclear Osmium and Ruthenium Complexes... 

Model of a chirally modified dinuclear osmium complex reacting with olefins at 0+. 

Heterometal alkoxide precursors, for ceramics, 12, 60-61 Heterometal chalcogenides, synthesis, 12, 62 Heterometal cubanes, as metal-organic precursor, 12, 39 Heterometallic alkenes, with platinum, 8, 639 Heterometallic alkynes, with platinum, models, 8, 650 Heterometallic clusters as heterogeneous catalyst precursors, 12, 767 in homogeneous catalysis, 12, 761 with Ni—M and Ni-C cr-bonded complexes, 8, 115 Heterometallic complexes with arene chromium carbonyls, 5, 259 bridged chromium isonitriles, 5, 274 with cyclopentadienyl hydride niobium moieties, 5, 72 with ruthenium—osmium, overview, 6, 1045—1116 with tungsten carbonyls, 5, 702 Heterometallic dimers, palladium complexes, 8, 210 Heterometallic iron-containing compounds cluster compounds, 6, 331 dinuclear compounds, 6, 319 overview, 6, 319-352... 

The highly toxic osmium complex Os3(CO)8(M-Cl)2PPh3 was immobilized via an anchored phosphine ligand as Os3(CO)8(/x-Cl)2Ph2P-[Res]. The bonding may be more complex, for example, Kalck and coworkers have proposed that each rhodium atom of the dinuclear carbonyl is anchored to the resin (equation 9) ... 

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