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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. 

The boron-centered reactivity of the diboraanthracene-auride complex ([Au(B2P2)][K(18-c-6)]; (B2P2, 9,10-bis(2-(diisopropylphosphino)- phenyl)-9,10-dihydroboranthrene) with a series of organic carbonyls is reported. The reaction of [(B2P2)Au]– with formaldehyde or paraformaldehyde results in a head-to-tail dimerization of two formaldehyde units across the boron centers. In contrast, the reaction of [(B2P2)Au]– with two equivalents of benzaldehyde yields the pinacol coupling product via C–C bond formation. Careful stoichiometric addition of one equivalent of benzaldehyde to [Au(B2P2)]– enabled the isolation of an adduct corresponding to the formal [4+2] cycloaddition of the C=O bond of benzaldehyde across the boron centers. This adduct reacts with a second equivalent of benzaldehyde to produce the pinacol coupling product. Finally, the reaction of [Au(B2P2)]– with acetone results in a formal reductive deoxygenation with discrete hydroxo and 2-propenyl units bound to the boron centers. This reaction is proposed to proceed via an analogous [4+2] cycloadduct, highlighting the unique small molecule activation chemistry available to this platform.