Room-Temperature C----C Bond Cleavage of an Arene by a Metallacarborane

On the fly: Reduction of 1,1′‐bis(o‐carborane) and subsequent reaction with a source of {Ru(p‐cymene)}2+ fragments yields a fly‐over bridge species resulting from room‐temperature CC bond cleavage of a p‐cymene ligand. DFT calculations suggest that the arene is sandwiched between two Ru atoms as part of a metallacarborane (see picture; C gray, B yellow, Ru red) and reduced by the second, pendant, carborane.