Active oxygen hydrogen peroxide

Compounds and complexes of the early transition metals are oxophilic because the low d-electron count invites the stabilization of metal-oxo bonds by 7T-bond formation. To a substantial extent, their reactivity is typical of complexes of metals other than rhenium. That is particularly the case insofar as activation of hydrogen peroxide is concerned. Catalysis by d° metals - not only Revn, but also CrVI, WVI, MoVI, Vv, ZrIV and HfIV - has been noted. The parent forms of these compounds have at least one oxo group. Again the issue is the coordination of the oxygen donating substrate, HOOH, to the metal, usually by condensation ... 

Active carbon, hydrogen peroxide determination, 638 Active oxygen see Peroxide value ACV see Acidity value... 

Although unstable with respect to water and oxygen, hydrogen peroxide decomposes only very slowly at room temperature because the reaction has a high activation energy (76 kj/mol). In the presence of iodide ion, however, the reaction is appreciably faster (Figure 12.16) because it can proceed by a different, lower-energy pathway ... 

In fact, carbon and graphite exhibit good electrochemical activities for oxygen reduction, high overpotential for hydrogen evolution, and low catalytic activity for hydrogen peroxide decomposition (Do and Chen 1994a, b Ponce-de-Leon and Pletcher 1995). 

The author hopes that the chapter has shown how the reactivity, and selectivity towards oxygen transfer reactions of hydrogen peroxide can be utilized for synthetic purposes. Generally, for laboratory and industrial application, activation of hydrogen peroxide by transition metal ions is the method of choice, although in a number of cases, the transition metal route can lead to disposal and environmental problems. The reaction of hydrogen peroxide with organic compounds can, therefore, provide a viable alternative to metal ion activation. 

Several heterogeneous catalysts have been developed for the hydroxylation of alkanes under mild conditions.68,69 One of them is the bi-catalytic system, which combines the ability of palladium to convert hydrogen and oxygen to hydrogen peroxide, with the capability of the iron ions to activate the hydrogen peroxide to hydroxylate hydrocarbons.70 Iron oxide and palladium supported on silica have been used as efficient catalysts for the oxidation of cyclohexane to the alcohol and ketone, via the in situ generation of hydrogen peroxide in an acetone solvent.71... 

Sobkowiak, Andrzej, Tung, Hui-Chan, and Sawyer, Donald T, Iron-and Cobalt-Induced Activation of Hydrogen Peroxide and Dioxygen for the Selective Oxidation-Dehydrogenation and Oxygenation of Organic... 

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