The reactivity of Fe(Cl) 2 (T(OMe)PP-Cl) (T(OMe)PP = meso -tetra(4-methoxy-phenyl)porphyrinyl) towards a series of substituted phenols was investigated. The oxidation reaction proceeded via a hydrogen atom transfer (HAT) mechanism where Fe(Cl) 2 (T(OMe)PP-Cl) displayed entropy of activation values typical of a metal-mediated HAT. In contrast, for hydrocarbon oxidation the entropy of activation indicated an organic radical-mediated HAT reaction, we address this dichotomy. • The reactivity of Fe(Cl) 2 (T(OMe)PP-Cl) (T(OMe)PP = meso -tetra(4-methoxy-phenyl)porphyrinyl) towards a series of substituted phenols was investigated. The oxidation reaction proceeded via a hydrogen atom transfer (HAT) mechanism where Fe(Cl) 2 (T(OMe)PP-Cl) displayed entropy of activation values typical of a metal-mediated HAT. In contrast, for hydrocarbon oxidation the entropy of activation indicated an organic radical-mediated HAT reaction, we address this dichotomy.
Gericke et al. (Fri,) studied this question.