A Binuclear Isocyanide Azadithiolatoiron Complex Relevant to the Active Site of Fe‐Only Hydrogenases: Synthesis, Structure and Electrochemical Properties

Abstract

Abstract An aromatic isocyanide‐substituted diiron complex 5 has been synthesized as a mimic for the active site of Fe‐only hydrogenases. Its structure has been fully characterized by X‐ray crystallography. The 4‐iodophenylisocyanide ligands in 5 are in the basal positions and are nearly parallel to each other, with π–π stacking interactions. Four isomeric geometries of complex 5 have been optimized by DFT calculations, and the electrochemical properties of 5 have been investigated by cyclic voltammetry in the absence and presence of p ‐toluenesulfonic acid (HOTs). Analysis of the cyclic voltammetric curve indicates that the reduction event at about–1.43 V is electrocatalytically active to proton reduction. This potential is more positive than that of any functionalized propanedithiolatodiiron complex. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)