Binuclear ligands

L(37)0)Zn2]3 +, which exhibits a second-order rate constant that is 120-fold larger than that found for [(L360H)Zn]2+. This dramatic difference in reactivity for the binuclear complexes is attributed to cooperative interactions in [(L(37)0)Zn2]3 + that are not achievable using the binuclear ligands (L38-L40) shown in Fig. 71. For example, the two centers in [(L(37)0)Zn2]3+ may be an optimal distance to provide... 

Ort/io-substituted TPP derivatives have been used as binuclear ligand systems by choosing suitable substituents on the phenyl rings. For example, treatment of a,a,a,a-H2(TAn,PP) 129 with maleic anhydride gave the tetrakis(o-maleamoylphenyl)porphyrin... 

H2 or O2 from water in the presence of a sacrificial reductant or oxidant employ a mthenium complex, typically [Ru(bipy)2], as the photon absorber (96,97). A series of mixed binuclear mthenium complexes having a variety of bridging ligands have been the subject of numerous studies into the nature of bimolecular electron-transfer reactions and have been extensively reviewed (99—102). The first example of this system, reported in 1969 (103), is the Creutz-Taube complex [35599-57-6] [Ru2(pyz)(NH3. 

FIGURE 21.19 The binuclear center of cytochrome oxidase. A ligand, L (probably a cysteine S), is shown bridging the Cng and Fe L metal sites. 

The binuclear complex [Mo2Cl2N2o] features a terminal nitrido ligand, N=, as well as terminal and bridging azido ligands, i.e. [ (MoCl(N)(t, -N,)2(/t,t -Nt)l2] Concatenations larger than N3 are rare. The planar bridging N4... 

The nitrogen atom in ri -pyrrolylmanganesetricarbonyl forms a donor-acceptor bond with transition metals. Complexes in which the pyrrolyl ring behaves as a tt ligand for the manganese atom and n-donor for the other metal were synthesized 12 (M = Mn, Re) [78JOM(157)431]. The binuclear heterobimetallic complexes... 

Bimetallic catalysis by binuclear complexes of Cu, Fe, Mn, Ni, Pd, and Rh with heterocyclic ligands 98T12985. 

N-Heterocycles as ligands in dioxygen activation by enzymes containing binuclear nonheme iron clusters 96CRV2625. 

Macroheterocycles capable of forming binuclear complexes with a common ligand 96CC457. 

Intramolecular Au-Au interactions are found in some binuclear complexes (AuX)2, where X is a chelating ligand like dithiocarbamate, phosphine ylid (R2P(CH2)2) or bidentate phosphines. Therefore, in [Au(S2CNBu2)]2 the Au-Au distance is 2.78 A (Figure 4.50). 

In nickel and palladium dithiobenzoato complexes, four-membered chelate rings are formed (366), whereas, in the corresponding phenyl-dithio acetates [M2(S2CCH2Ph)4], the dithio ligands act as bridging groups between the two metal atoms, with the formation of binuclear units (367). The molecular structure of the latter compounds shows that each metal atom is coordinated to four sulfur atoms and to the other metal atoms in a square-pyramidal geometry. Other evidence for... 

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