The phenomenon of ‘dioxygen protection’ during autoxidation of a lacunar macrobicyclic iron(II) reversible dioxygen carrier. An outer-sphere autoxidation mechanism

Abstract

The autoxidation kinetics of an iron(II) complex which is a dioxygen carrier and which contains a sizeable protected cavity around one axial co-ordination site of the metal ion display a maximum in rate at ca. 1 Torr of dioxygen pressure at 0 °C and this unusual behaviour is interpreted as evidence for an outer-sphere oxidation mechanism involving hexaco-ordinated iron(II) species.