Oxyradical reactions: from bond‐dissociation energies to reduction potentials

[摘要]

Destructive radical reactions involve alkykl, alkoxyl and alkylperoxyl radicals, as well as alkylhydroperoxides. From bond energies the following reduction potentials vs NHE at neutral pH are derived: Esuo'(RO./ROH) = 1.6 V, E ^o'(ROO./ROOH) = 1.0 V, E ^o'(ROOH/RO., H₂;0) = 1.9 V, and the two-electron reduction potential E ^o'(ROOH/ROH, H₂O) = 1.7 V. Hydrogen abstraction from a bis-allylic methylene group by alkoxyl and alkylperoxyl radicals is favourable with Gibbs energies of −23 and −9 , respectively. Similarly, alkoxyl radicals can oxidize alkylhydroperoxides, ΔG^o' = −14 .

[学科分类] 生物化学/生物物理

[关键词] Lipid peroxidation;Reduction potential;Alkyl radical;Alkylperoxyl radical;Alkoxyl radical;Bond energy