A Combined Spectroelectrochemical and Computational Study of the Chemically Reversible 2-Electron Reduction of [Ru4(μ-RC2R)2(CO)11] Clusters

The 62-CVE clusters Ru4(μ-RC2R)2(CO)11, which feature a dodecahedral cluster core, are readily reduced to a 64-CVE dianion in a process that is essentially chemically reversible. A combination of electrochemical, spectroelectrochemical, and computational analyses of the system indicates that the first formed dianion, which features a square planar arrangement of the metal centers with the alkyne ligands located on opposite faces of the M4 square and oriented in a manner such that the C−C bonds are perpendicular to each other, undergoes a thermal rearrangement giving a product in which the alkyne vectors lie parallel to each other across the metal framework.