Iron porphyrins with a hydrogen bonding cavity: effect of weak interactions on their electronic structure and reactivity

Abstract

The electronic structure and reactivity of iron porphyrin complexes bearing 2^nd sphere hydrogen bonding residues have been investigated over the last few years. The presence of these weak interactions alters the spin ground state, and axial ligand bonding and provides a proton translocation pathway into the active site. Mechanistic investigations in organic as well as aqueous media demonstrate how controlled delivery of protons is fundamental in dictating the selectivity of a multi-electron multi-proton process like the reduction of dioxygen to water.