Chlorine peroxy radical, from

The effect of chlorine substitution is to reduce the C-O bond energy of the peroxy radicals from 32kcal/mol for CH302 to 20kcal/mol for CC1302. 

Self-Reaction Kinetics. Of all peroxy radical reactions, the self-reaction between two identical peroxy radicals is perhaps the most studied. The measurement of peroxy radical UV absorption cross sections, discussed above, often occurs under the assumption that all the chlorine or fluorine atoms produced by photolysis are converted quantitatively into peroxy radicals however, this assumption must be corrected for by the loss of peroxy radicals from self-reaction. Furthermore, studies of RO2 -b NO or RO2 -f HO2 reactions usually take place at sufficiently high RO2 concentrations to require knowledge of the self-reaction rate constant, in order to interpret the results of the kinetics measurements. Both concerns make laboratory studies of peroxy self-reaction kinetics an important issue. In contrast, the steady-state atmospheric concentrations of HCFC-based peroxy radicals are probably too small for their self-reactions to be relevant to atmospheric chemistry. In this context, the most important peroxy-peroxy radical reactions would be between the HCFC-based peroxy radicals and CH3O2, but such reactions have not been studied to date. 

Martinez GR, Medeiros MHG, Ravanat J-L, Cadet J, Di Mascio P (2002) [0ls]-Labeled singlet oxygen as a tool for mechanistic studies of 8-oxo-7,8-dihydroguanine oxidative damage detection of spiroiminodihydantoin, imidazolone and oxazolone derivatives. Biol Chem 383 607-617 Martini M, Termini J (1997) Peroxy radical oxidation of thymidine. Chem Res Toxicol 10 234-241 Merenyi G, Lind J, Shen X (1988) Electron transfer from indoles, phenol, and sulfite (S032T to chlorine dioxide (CICV). J Phys Chem 92 134-137... 

The reaction stoichiometries, product profiles, and apparent second-order rate constants for the combination of perfluoroaromatic molecules (and several hydro and dihydro derivatives) with excess superoxide ion in dimethylformamide are summarized in Table 7-1. The primary product from the combination of C6F6 with 2 equivalents of O2-- is CeEgOO on the basis of the F-NMR spectrum of the product solution and the mass spectrum for the major peak from the capillary GC of the product solution.24 Similar analyses of the product solutions for the other fluoro substrates are consistent with a peroxide product from the displacement of a fluoride ion. A reasonable first step for these oxygenations is nucleophilic addition of O2 - to the polyfluoroaromatic. Subsequent loss of fluoride ion will give an aryl peroxy radical, which will be reduced by a second O2-- to the aryl peroxide product. This reaction sequence (with the initial nucleophilic displacement the rate-determining step) is analogous to that observed for chlorohydrocarbons and polychlorobenzenes (Scheme 7-8). However, the peroxo product of the latter systems is an effective nucleophile that attacks a second substrate molecule (or an adjacent aryl chlorine... 

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