Dioxygen chemistry

In summary, the cooperative behavior of the two metal ions determines the dioxygen chemistry of group 2 bis-Co porphyrins and certain flexible group 1 analogs (e.g., a... 

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-... 

As a part of their work on copper(I)-dioxygen chemistry, Schindler and co-workers220 synthesized copper(I) (Section 6.6.4.2.2(iv)) and copper(II) complexes ((235) r = 0.12, and (236) r = 0.08) of a few tetradentate ligands, varying in their flexibility due to the presence of different chelate ring-forming arms, and studied their redox properties. Karlin and co-workers observed a... 

Finally, kinetic and mechanistic studies of autoxidation reactions will not only lead to a better understanding of these essential reactions but also may trigger extensive studies on various areas of dioxygen chemistry. 

There has been enormous activity in the field of copper(I)-dioxygen chemistry in the last 25 years, with our information coming from both biochemical-biophysical studies and to a very important extent from coordination chemistry. This has resulted in the structural and spectroscopic characterization of a large number of copper dioxygen complexes, some of which are represented in Figure 14.2. The complex F, first characterized in a synthetic system was subsequently established to be present in oxy-haemocyanin, and is found in derivatives of tyrosinase and catechol oxidase, implying its involvement in aromatic hydroxylations in both enzymes and chemical systems. 

Hatcher, L.Q. and Karlin, K.D. (2004) Oxidant types in copper-dioxygen chemistry the ligand coordination defines the Cun-02 structure and subsequent reactivity, J. Biol. Inorg. Chem., 9, 669-683. 

Qin K (2003) Dioxygen Chemistry of Hydrotris(pyrazolyl)borate Chromium(ll) Complexes. PhD Thesis, University of Delaware... 

Oxo- and Hydroxo-Bridged Heme-Copper Assemblies Formed from Acid-Base or Metal-Dioxygen Chemistry (Kopf et al., 1999)... 

As the focus of this review is on copper-dioxygen chemistry, we shall briefly summarize major aspects of the active site chemistry of those proteins involved in 02 processing. The active site structure and chemistry of hemocyanin (He, 02 carrier) and tyrosinase (Tyr, monooxygenase) will be emphasized, since the chemical studies described herein are most relevant to their function. The major classes of these proteins and their origins, primary functions, and leading references are provided in Table 1. Other classes of copper proteins not included here are blue electron carriers [13], copper-thiolate proteins (metallothioneines) [17], and NO reductases (e.g., nitrite [NIR] [18] or nitrous oxide [19]). 

A side-on p,-Tq2 Tq2-peroxo dicopper(II) complex. A very important development in copper-dioxygen chemistry occurred in 1989 with the report by Kitajima et al. [10,108] that another Cu202 species could be prepared and structurally characterized by using copper complexes with a substituted anionic tris(pyrazolyl)borate ligand. This intensely purple compound, Cu[HB(3,5-iPr2pz)3] 2(02) (5), was prepared either by reaction of Cu[HB(3,5-iPr2pz)3] (4) with 02 or by careful addition of aqueous hydrogen peroxide to the p-dihydroxo... 

Murthy and Karlin Biomimetic Copper-Dioxygen Chemistry 167... 

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