Aspects of the HO2· Elimination Reaction from Organic Peroxyl Radicals: Some Recent Examples
It is known that in aqueous solution some organic radicals upon reaction with oxygen form HO 2 · /·O 2 - without a detectable peroxyl radical intermediate. Cases in point are the radicals derived from formate1, formaldehyde hydrate2 and glucose (at C(l)).3 Many other radicals carrying OH or NH functions in α-position to the radical site form peroxyl radicals whose rate of spontaneous HO2 elimination can be measured. Among these are the peroxyl radicals derived from alcohols, carbohydrates (for a review see reference 4) and amino acids.5 However, in some cases this elimination reaction is very slow and HO 2 · is practically only eliminated in a base-catalysed reaction. In this case a peroxyl radical anion is a likely intermediate which subsequently loses ·O2 Examples are the peroxyl radicals derived from pyrimidines.6 In continuation of these studies we have been looking at the OH radical-induced oxidation of trimethylamine, acetaldehyde dimethylacetal, glycine anhydride and benzene. Peroxyl radicals derived from these substrates were generated radiolytically as described in the preceding paper by C. von Sonntag.
KeywordsPeroxyl Radical Peroxy Radical Pulse Radiolysis Elimination Reaction Methyl Acetate
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