From Au(11) to Au(13): Tailored Synthesis of Superatomic Di-NHC/PPh(3)-Stabilized Molecular Gold Nanoclusters

[Image: see text] Herein, we report a new method to synthesize molecular gold nanoclusters (AuNCs) stabilized by phosphine (PR(3)) and di-N-heterocyclic carbene (di-NHC) ligands. The interaction of di-NHC gold(I) complexes, with the general formula [(di-NHC)Au(2)Cl(2)] with well-known [Au(11)(PPh(3))(8)Cl(2)]Cl clusters provides three new classes of AuNCs through a controllable reaction sequence. The synthesis involves an initial ligand metathesis reaction to produce [Au(11)(di-NHC)(PPh(3))(6)Cl(2)](+) (type 1 clusters), followed by a thermally induced rearrangement/metal complex addition with the formation of Au(13) clusters [Au(13)(di-NHC)(2)(PPh(3))(4)Cl(4)](+) (type 2 clusters). Finally, an additional metathesis process yields [Au(13)(di-NHC)(3)(PPh(3))(3)Cl(3)](2+) (type 3 clusters). The electronic and steric properties of the employed di-NHC ligand affect the product distribution, leading to the isolation and full characterization of different clusters as the main product. A type 3 cluster has been also structurally characterized and was preliminarily found to be strongly emissive in solution.