Proton‐ and Reductant‐Assisted Dioxygen Activation by a Nonheme Iron(II) Complex to Form an Oxoiron(IV) Intermediate

With a little help from some friends: With the aid of HClO4 as proton and BPh4− as electron source, the Fe complex of a pentadentate pyridyl-appended cyclam ligand can activate dioxygen to yield the corresponding oxoiron(IV) complex (see scheme; TMC-py=1-(2′-pyridylmethyl)-4,8,11-trimethyl-1,4,8,11-tetraazacyclotetradecane; C gray, Fe magenta, N blue, O red). This transformation is proposed to occur via a hydroperoxoiron(III) intermediate.