Metal-catalysed oxidation

R. A. Sheldon and J. K. Kochi, Metal-Catalysed Oxidations of Organic Compounds, Academic Press, Inc., New York, 1981. 

Retard efficiently oxidation of polymers catalysed by metal impurities. Function by chelation. Effective metal deactivators are complexing agents which have the ability to co-ordinate the vacant orbitals of transition metal ions to their maximum co-ordination number and thus inhibit co-ordination of hydroperoxides to metal ions. Main use of stabilisation against metal-catalysed oxidation is in wire and cable applications where hydrocarbon materials are in contact with metallic compounds, e.g. copper. 

Pinene hydroperoxide (PHP) when compared with r-butyl hydroperoxide has been proposed as an excellent mechanistic probe in metal-catalysed oxidations. " If inter-molecular oxygen transfer from a peroxometal species to the substrate is rate limiting, the bulky PHP is unreactive, but for reaction of an oxometal species as the rate-limiting step, little or no difference is observed and only small differences in reactivity are observed when re-oxidation of the catalyst by ROOH to an active oxometal species is the rate-limiting step. 

Multinuclear NMR and ESR spectroscopy have been employed for the in situ detection and characterization of reactive intermediates in a variety of transition metal-catalysed oxidations.48... 

Oxidation with ozone, under physiological conditions, follows the rate order uric acid ascorbic acid > glutathione. The amounts of ozone absorbed and antioxidant consumed have been simulated with a mathematical model and reaction rate constants of the oxidations have been evaluated.194 Various facets of transition metal-catalysed oxidation of benzylic compounds with ozone have been reported. The correlation of the effect of substituents with Hammett constants and steric factors has been discussed. The reaction seemed to proceed via a radical mechanism.195... 

Although metal-catalysed oxidation can lead to glucosone and H202, the existence of amadoriases suggests that Amadori products might well be involved. 

R.A. Sheldon and J.K. Kochi, "Metal Catalysed Oxidations of Organic Compounds", Academic Press, New York, 1981 S.V. Ley, J. Norman, W.P. Griffith and S.P. Marsden, Synthesis, 1994, 639 M. Hudlicky, "Oxidations in Organic Chemistry", ACS, Washington, DC, 1990 and references cited therein. 

Sheldon, R. A., Kochi, J. K. Metal catalysed oxidations of organic compounds. Academic Press, New York 1981, chapter 4... 

Histidine is frequently involved in the co-ordination of metal ions, and is thus a target for metal-catalysed oxidation [95], generating 2-oxo-histidine and its ring-ruptured products. It has also been postulated that the formation of Schiff bases between newly formed carbonyl moieties and epsilon amino groups on lysine residues may account for protein aggregation. 

R.A. Sheldon and J.K. Kochi, in Metal catalysed oxidations of Organic compounds Academic Press, 1981. 

Dyrks, T., Dyrks, E., Hartmann, T., Masters, C. and Beyreuther, K. (1992) Amyloidogenicity of beta Ad-bearing amyloid protein precursor fragment by metal-catalysed oxidation. 7. Biol. Chem. 267 18210-18217. 

Numerous methods have been developed for the oxidation of 70 to 68. Transition metal-catalysed oxidation by oxygen, for example with manganese salts in DMF [80] or with vanadium acetylacetonate in pyridine [81] have industrial advantages. Overall yields greater than 80 % are achieved in the two-step reaction from 69 to 68. 

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