O-O Bond Formation and Liberation of Dioxygen Mediated by N₅ -Coordinate Non-Heme Iron(IV) Complexes.

ABSTRACT: Formation of the O-O bond is considered the critical step in oxidative water cleavage to produce dioxygen. High-valent metal complexes with terminal oxo (oxido) ligands are commonly regarded as instrumental for oxygen evolution, but direct experimental evidence is lacking. Herein, we describe the formation of the O-O bond in solution, from non-heme, N₅ -coordinate oxoiron(IV) species. Oxygen evolution from oxoiron(IV) is instantaneous once meta-chloroperbenzoic acid is administered in excess. Oxygen-isotope labeling reveals two sources of dioxygen, pointing to mechanistic branching between HAT (hydrogen atom transfer)-initiated free-radical pathways of the peroxides, which are typical of catalase-like reactivity, and iron-borne O-O coupling, which is unprecedented for non-heme/p

SUBMITTER: Kroll N 

PROVIDER: S-EPMC6772150 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature