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Abstract Ferrocene1and its dianionic Fe(bis)(dicarbollide) analogue2are classical compounds that display unusual stability. These compounds are not known to undergo transmetallation chemistry of the Fe‐center and have been used extensively as chemical building blocks with consistent integrity. In this manuscript we describe the preparation of a charge compensated Fe(bis)(dicarbollide) species3 Feand its unprecedented transmetallation chemistry to Ir. Such reactions are hitherto unknown for any transition metal metallocene or metallacarborane complex. Additionally, we show that3 Fecan be deprotonated to afford the corresponding bis(NHC) Li‐carbenoid5that also displays unique reactivity. When5is reacted with [Ir(COD)Cl]₂it also undergoes a rapid transmetallation of the ferrocene “like” core to afford6but with the added twist that the Li‐carbenoid moiety stays intact and does not transmetalate. However, when6is subsequently treated with CuCl, the Li‐carbenoid transmetalates to Cu, which allows the controlled formation of the corresponding heterobimetallic Ir/Cu aggregate. Lastly, when Li‐carbenoid5is treated directly with CuCl, a double transmetallation occurs from both Fe to Cu and Li‐carbenoid to Cu, resulting in the trimetallic Cu cluster8. These novel reactions pave the way for new synthetic methods to build complicated polymetallic clusters in a controlled fashion. 

Discovered by Knöth in 1964, the 10-vertex closo -carborane anion [HCB 9 H 9 1− ] is a classical bicapped square antiprism that contains an unusual pentacoordinate carbon center. Compared to its larger icosahedral cousin [HCB 11 H 11 1− ], few investigations have been made into its use as a weakly coordinating anion or as a ligand substituent. Here we show that it is possible to prepare both a dianionic N-heterocyclic carbene (NHC) Li + adduct as well as a trianionic C-2, C-5 dilithio species featuring two 10-vertex carborane anion substituents. All compounds were characterized via multinuclear NMR spectroscopy, single crystal X-ray diffraction, and HRMS when possible.