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Metal bonded complexes, trinuclear

Mo, W) are very useful reagents in organometallic chemistry, in particular for the formation of metal-metal bonded complexes. This is illustrated below by the high-yield synthesis of a heterotrinuclear complex having a linear M— Pt—M core, Section C. The trinuclear complexes M—M —M react with tertiary phosphines3,4 to give heterotetranuclear clusters M2M 2( 7-C5H5)2 (CO)6(PR3)2 and details of the synthesis of two of these (M = Mo M = Pd, Pt) are presented in Section D. [Pg.342]

Table V summarizes the key photochemistry of trinuclear metal-metal bonded complexes. The first noteworthy photochemical study of trinuclear complexes concerns Ru3(CO)j2. This species was found to undergo declusterification to mononuclear fragments when irradiated in the presence of entering ligands such as CO, PPh3,°T ethylene. The intriguing finding is that thermal reaction of Ru3(C0)12 with PPh3 results in the substitution product indicated in equation (18) whereas irradiation yields the mononuclear species given by equation (19) (57). These results... Table V summarizes the key photochemistry of trinuclear metal-metal bonded complexes. The first noteworthy photochemical study of trinuclear complexes concerns Ru3(CO)j2. This species was found to undergo declusterification to mononuclear fragments when irradiated in the presence of entering ligands such as CO, PPh3,°T ethylene. The intriguing finding is that thermal reaction of Ru3(C0)12 with PPh3 results in the substitution product indicated in equation (18) whereas irradiation yields the mononuclear species given by equation (19) (57). These results...
Excited states associated with metal-metal bonded complexes. Other types of decay mechanisms are found from excited states of organo-metallic compounds having direct metal-metal bonds. Iradiation of dinu-clear and trinuclear metal-metal bonded complexes leads to efficient metal-metal bond clevage generating highly reactive mononuclear frag-... [Pg.365]

Given the well documented role of homolytic cleavage of metal-metal bonds in the photoreactions of dimeric complexes (7), a logical hypothesis would be for the photofragmentations of trinuclear complexes to follow a similar path, e.g.,... [Pg.128]

Let us start our examination with the dpa-metal complexes. A series of trimetallic complexes of general formula [M3(dpa)4Cl2] (M = Cr,30 Ni,31 Co,32 Cu,33 Ru,34 Rh,34) have been structurally characterized. As illustrated in Scheme 2, such trinuclear complexes in the solid state can display either a symmetrical or an unsymmetrical M3 chain, depending upon if the metal-metal bond is extended over the three metal atoms, or is localized only between two metal atoms.35... [Pg.524]

The number of central atoms joined in a single coordination entity or cluster by bridging ligands or by metal-metal bonds. Such complexes are referred to as being dinuclear, trinuclear, tetranuclear, polynuclear, etc. [Pg.512]

In addition to those complexes summarized in Tables I—III, X-ray structural analyses of some bi- and trinuclear complexes with a supporting metal-metal bond,1 -115 a trinuclear complex without a metal-metal bond supporting the bridge,3839 116 and two trinuclear osmium complexes with a terminal diphenylthioketone ligand117 have been reported. [Pg.140]

A new class of binuclear nitrido complexes of tetravalent osmium and ruthenium is described in which the metal atoms are symmetrically bridged by a nitride ligand to give a linear M-N—M unit They have the stoichiometries M2NX8(H20)2]3 and [M2N(NH3)8Y2]3+ (M = Os, Ru X = Cl, Br Y = Cl, Br, etc.). Studies are reported on their vibrational spectra, structures, and bonding. Preliminary studies are reported also on trinuclear complexes of osmium and iridium. Finally, the use of vibrational spectroscopy in the study of metal-nitrido and metal-oxo complexes is discussed briefly. [Pg.54]

The mechanisms of these reactions are probably complex but radical processes seem likely. The final products of insertion into the metal metal bond are actually trinuclear species. Insertion into terminal metal hydride or metal alkyl bonds could, in principle, generate mixed-metal dimers. In practice, aside from insertion into the metal halogen bond, such as that shown in equation (65), few such reactions have been reported. [Pg.1153]

The trinuclear framework with three metal-metal bonds is remarkably stable and supports a rich array of chemical reactions. A related triangular complex with a remarkable bridging PF3 group is obtained by disproportionation reaction [eq. (b)] which produces two new Pd-Pd bonds with rearrangement of the diphosphine ligands. ... [Pg.189]


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See also in sourсe #XX -- [ Pg.103 ]




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Trinuclear

Trinuclear complexes

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