Self‐Assembly of Benzimidazole‐Derived Tris‐NHC Ligands and Ag I ‐Ions to Hexanuclear Organometallic Cages and Their Unusual Transmetalation Chemistry

Multi‐ligand self‐assembly to attain the Ag I ‐N‐heterocyclic carbene (NHC)‐built hexanuclear organometallic cages of composition [Ag 6 ( 3 a , b ) 4 ](PF 6 ) 6 from the reaction of benzimidazole‐derived tris(azolium) salts [H 3 ‐ 3 a , b ](PF 6 ) 3 with Ag 2 O was achieved. The molecular structures of the cages were established by X‐ray diffraction studies along with NMR and MS analyses. The existence of a single assembly in solution was supported by diffusion‐ordered spectroscopy (DOSY) 1 H NMR spectra. Further, transmetalation reactions of these self‐assembled complexes, [Ag 6 ( 3 a , b ) 4 ](PF 6 ) 6 , with Cu I /Au I ‐ions provided various coinage metal‐NHC complexes having diverse molecular compositions, which included the first example of a hexanuclear Cu I ‐dodecacarbene complex, [Cu 6 ( 3 b ) 4 ](PF 6 ) 6 .