A Chiral Gold Nanocluster Au₂₀ Protected by Tetradentate Phosphine Ligands

The chirality of a gold nanocluster can be generated from either an intrinsically chiral inorganic core or an achiral inorganic core in a chiral environment. The first structural determination of a gold nanocluster containing an intrinsic chiral inorganic core is reported. The chiral gold nanocluster [Au 20 (PP 3 ) 4 ]Cl 4 (PP 3 =tris(2‐(diphenylphosphino)ethyl)phosphine) has been prepared by the reduction of a gold(I)–tetraphosphine precursor in dichloromethane solution. Single‐crystal structural determination reveals that the cluster molecular structure has C 3 symmetry. It consists of a Au 20 core consolidated by four peripheral tetraphosphines. The Au 20 core can be viewed as the combination of an icosahedral Au 13 and a helical Y‐shaped Au 7 motif. The identity of this Au 20 cluster is confirmed by ESI‐MS. The chelation of multidentate phosphines enhances the stability of this Au 20 cluster.