Peroxo dinuclear copper complexes

Oxygenic photosynthetic organisms, [2Fe-2S] ferredoxins, 38 224-233 Oxygenyl ion, preparation of, 9 229 Oxyhalides, of berkelium, 28 49, 51-53 Oxyhalogeno cations, 9 276-279 Oxyhemerythrin, 40 373-374, 45 84 XAS, 36 325 Oxyhemocyanin, 40 363 m-peroxo dinuclear copper complexes as models for, 39 41-52 physicochemical properties, 39 47-48 Oxyhemocyanins, XAS, 36 326-327 Oxyhemoglobin, 21 135 Oxyiodonium cations, 9 277 Oxymanganese phthalocyanine, strucmre of, 7 31-35... 

A. ix-Peroxo Dinuclear Copper Complexes as Models for Oxyhemocyanin and... 

B. Reaction Aspects of p,-Peroxo Dinuclear Copper Complexes Relevant to Tyrosinase Catalysis... 

CU2O2 structure 13 3 (a tran5- X-l,2-peroxo complex). In both cases association of two mononuclear copper(I) centers takes place. These functional mimics of O2 activating systems provide the key information for further design of dinuclear copper complexes with oxygenase activity. 

Extensive synthetic endeavors undertaken for the last decade produced a number of i-peroxo dinuclear copper(II) complexes credibly characterized. These include the peroxo complex [Cu(HB(3,5-iPr2pz)3)]2(02) and trans- i-peTo o complex... 

During the course of modeling copper dioxygen chemistry, Kitajima et al. reported the synthesis of a yu-peroxo dinuclear complex with a 3,5-dimethyl-substituted tris(pyrazolyl)borate ligand, which showed remarkable physicochemical similarities to oxy-Hc and oxy-Tyr. Using a 3,5-di-isopropyl-substituted terminal ligand, they provided the first structural proof of the existence of peroxo dicopper(II) core (108) (copper geometry distorted square pyrami-... 

Interaction of dioxygen species with Fe aq and with Fe " aq has been very briefly reviewed. In relation to 0x0-, peroxo-, and superoxo-complexes as models for intermediates in oxygenase activity, a brief report on a 2000 symposium on activation of oxygen summarizes the then-current situation in the search for a mechanism common to mono- and dinuclear iron sites, mono- and dinuclear copper sites, and copper-iron sites. The outline proposals comprise ... 

In continuing low-temperature kinetic studies of halo-Cu(I)-amine reactions with 02, Davies et al. have observed and partially characterized per-oxo-copper(II) complexes for L2Cu2C12 (L = teed) [96,97]. At room temperature, complete reduction of dioxygen occurs to give green, dinuclear LCu(Cl,0,Cl)CuL, but at lower temperatures (i.e., <-26°C) two forms of a tetra-nuclear mixed-valence peroxo Cu(II) complex exist in equilibrium. In particular, one of the forms is associated with 380 (e = 1600 M l cm-1) and 650 (e = 650) nm electronic spectral absorptions and a resonance Raman Vo 0 band at 822 cm-1. 

A trans-n- 1,2-Peroxo Dicopper(II) Complex. Our own efforts have resulted in the structural and spectroscopic characterization of five types of copper-dioxygen complexes (6), distinguished on the basis of the ligands used for their synthesis and on their distinctive structures or physical properties. Thus, the manner in which hemocyanin binds 02 is not the only one possible, and it is of considerable interest to deduce the structures, along with associated spectroscopy and reactivity of a variety of types. Dioxygen can bind to dinuclear transition metals in a variety of structural modes, shown in Figure 2. As mentioned, mode C is present in oxy-Hc and Kitajima s model complex (Scheme 1), whereas we have structural and spectroscopic evidence for types A (30-32), B (33-35), and F (36-38) for peroxo 022- binding, and mode D (39, 40) in the case of hydroperoxo (OOH ) complexes. 

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