Hydrogen Atom Abstraction and Hydride Transfer Reactions by Iron(IV)–Oxo Porphyrins

True identity revealed: The CH bond activation of alkyl aromatics by synthetic iron(IV)–oxo porphyrin species and the hydride transfer of NADH analogues to them occur through H-atom abstraction and proton-coupled electron-transfer mechanisms, respectively. Mechanistic studies revealed that iron(IV)–oxo porphyrins, not iron(IV)–oxo porphyrin π-radical cations, are the true oxidant.