Iron complexes with an N/S chromophore relevant to the active site of the hydrolytic metalloenzyme nitrile hydratase

Abstract

Iron(III) complexes with a 3N/3S chromophore reproduce a mixed N/S heterocyclic ligand environment, metal–ligand bond lengths, and low-spin state (S = 1/2) characteristic of the hydrolytic metalloenzyme nitrile hydratase; Fe ^III N ₂ S ₂ Cl species possesses a quantum mechanically admixed S = 3/2, 5/2 state and able to form low-spin solvent adducts, possible analogues of the substrate-bound form of the enzyme.