ELECTROCHEMISTRY OF ACETYLIDE COMPLEXES OF IRON

The synthesis of a symmetrical acetylide-bridged, diiron(II) complex, ClFe(DMPE)2(C=CC6H4C=C)-(DMPE)2FeCl (1) (DMPE = bis(dimethylphosphine)ethane) is reported. Electrochemistry and EPR spectroscopy are used to examine the redox properties of 1 as well as the mononuclear iron(II) complexes Fe(DMPE)2Cl2 (2), ClFe(DMPE)2(C=CPh) (3), and Fe(DMPE)2(C=CPh)2 (4). Evidence for the corresponding iron(III) and iron(IV) species is provided. The structural rearrangements accompanying redox changes are discussed on the basis of the electrochemical characteristics. The electrochemical behaviour of the bridged diiron species 1 provides evidence that the two metal centres interact electronically.