A facile structural rearrangement to unprecedented µ2-η6:η6-bis(cyclopentadienylidene)ethene diruthenium complexes in the oxidation of 1,2-bis(ruthenocenyl)ethynesElectronic supplementary information (ESI) available: elemental analysis, 1H and 13C NMR, IR and Raman spectra. See http://www.rsc.org/suppdata/cc/b2/b202811p/