Cubanes oxide metal complexes

The fully oxidized nature of cluster (7) generates significant reactivity properties. The cluster cannot be reversibly reduced, but it does react with FeCl2 to form an Fc4S4 cluster and with reduced metal complexes to afford heterometal cubane-type clusters.Reaction... 

In recent years, sulfur, both in its atomic and molecular (e.g., S2) forms, has been noted to be a remarkably versatile ligand in transition metal complexes. It has been found to bridge two, three, or even four metal atoms and thus readily lends itself to the study of polynuclear complexes. One of the classic examples is [CpFeS]4 (Cp = tj -CjHs), a cubane cluster containing triply bridging sulfiir atoms. An important property of these cluster compounds is their general tendency to undergo reversible redox reactions via modification of metal-metal interactions. For example, [CpFeS]4 can exist in several different molecular oxidation states, ... 

Tetranuclear manganese(III) carboxylate complexes have three different configurations for their metal centers fused open cubane, planar, or butterfly (see Figure 22). There is only one example of the first type namely [Mn4Q2(OAc)2(BSP)2] (105). The Mn Mn separations in (105) vary between 2.875(1)A and 3.122(1)A. Variable temperature magnetic measurements for (105) indicated weak antiferromagnetic interactions (/=—10.0cm and / = —3.7cm ) between the manganese(III) centers. Cyclic voltammetry of (105) in methanol shows one quasireversible oxidation wave at 0.01 V and two quasireversible reduction waves at about —0.4 V and —0.7 V vs. SCE. 

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... 

An electrochemical analysis has been carried out on the pseudo-cubane cluster [Cp Ti]2P6 486 It was found to undergo an electrochemically irreversible oxidation at Epa = 0.70 V and a reversible reduction at -1.31 V. The unpaired electron in the radical anion appears largely localized on the metal centers. The difference in oxidation and reduction potentials was found to be considerably larger than for the triple-decker complexes [Cp M]2P6 (M = Mo, W, V), which also contained an E6 group but one that is planar.487... 

Follow-up products may include metal oxides, be it in a mononuclear or in a di-and oligonuclear form (Eqs. 2-4). The tetranuclear rhenium(I) complex formed by photolysis (Eq. 4) has a cubane-type structure [7]. Related complexes 2a-d were made according to Scheme 2 [8],... 

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