Noble Metal Corrosion: Halogen Bonded Iodocarbenium Iodides Dissolve Elemental Gold—Direct Access to Gold–Carbene Complexes

A common method to dissolve elemental gold involves the combination of an oxidant with a Lewis base that coordinates to the gold surface, thus lowering the metal's redox potential. Herein we report the usage of organic iodide salts, which provide both oxidative power and a coordinating ligand, to dissolve gold under formation of organo‐gold complexes. The obtained products were identified as AuIII complexes, all featuring Au−C bonds, as shown by X‐ray single‐crystal analysis, and can be isolated in good yields. Additionally, our method provides direct access to N‐heterocyclic carbene (NHC‐type) complexes and avoids costly organometallic precursors. The investigated complexes show dynamic behavior in acetonitrile and in the case of the NHC(‐type) complexes, the involved species could be identified as a monocarbene [AuI3(carbene)] and biscarbene complex [AuI2(carbene)2]+. Organic iodide salts, providing both oxidative power and coordinating ligand, dissolve elemental gold under formation of organo‐gold complexes. The obtained products were identified as AuIII complexes, all featuring Au−C bonds, as shown by X‐ray single‐crystal analyses. This method also provides direct access to N‐heterocyclic carbene‐ (‐type) complexes and avoids costly organometallic precursors.