C-H Bond Activation by a Ferric Methoxide Complex: A Model for the Rate-Determining Step in the Mechanism of Lipoxygenase

摘要

A new pentadentate ligand, PY5, has been designed and synthesized to mimic the Lewis acidic iron site in LOs. The ferric-methoxide complex of PY5 is reduced by substrates with weak C-H bonds to yield the ferrous-methanol complex in a process most consistent with HA from substrate. This provides not only the first chemical precedent for the proposed RDS in the mechanism of LOs but also a thermodynamic rational of why this reaction is favorable.