Peroxy radicals benzylperoxy

Table 4 Comparison of reaction pathway energetics (kcal/mol) for benzylperoxy radical and 2-picolinylperoxy radical at 298 K, via B3LYP/6-311+G //B3LYP/6-31G. Numbers refer to pathways depicted in Fig. 18. All enthalpies and free energies are relative to the peroxy radical (2) when preceded by TS, the relative data are the enthalpy and free energies of activation...

In the case of the methyl peroxy radical, for example, the presence of an F atom, Cl atom (s), or OH group, increases the rate constant by more than a factor of 10. The effect of bromine, on the contrary seems smaller. The enhancement is even larger with the presence of a carbonyl group e.g. acetonylperoxy) or an aromatic ring e.g, benzylperoxy). 

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