Five oxidation states in metal-bonded C4 chains

Abstract

The 36-electron diruthenium buta-l,3-diynyl complexes [Ru]C C–C C[Ru] [Ru = Ru(PPh3)2Cp and Ru(PMe3)(PPh3)Cp] undergo four stepwise one-electron oxidation–reduction processes by cyclic voltammetry; some of the oxidised complexes have also been prepared by chemical oxidation.