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The low valent gallium(I) compound GaCp was primarily used in gold cluster chemistry to synthesize the superatomic cluster [(PPh3)8Au9GaCl2]2+, complementing the borane-dominated set of reducing agents in gold chemistry, opening a whole new field for further research. Using density functional theory calculations, the cluster can be described by the jellium model as an 8-electron superatom cluster. [ABSTRACT FROM AUTHOR]

The reaction of Et3PAuCl with NaBH4 in EtOH leads to the metalloid gold cluster Au32(Et3P)12Cl8 (Au32) or Au54(Et3P)18Cl12 (Au54) depending on the work-up procedure of the reaction mixture. The molecular structure of Au54 is determined by X-ray diffraction and can be described as a fusion of two Au32 clusters showing a similar solubility. The metalloid cluster Au54 can be either described by a shell model or as a combination of tetrahedral Au4X units (X = Cl, Et3P); edge and face sharing, whereas tetrahedral Au4 units are a central motif in gold cluster chemistry. This novel Au54 gold cluster gives another unique insight into the formation or decomposition process of metalloid clusters, indicating that Au32 and Au54 form from a single yet unknown cluster source. [ABSTRACT FROM AUTHOR]

Three multi‐shell metalloid gold clusters of the composition Au32(R3P)12Cl8 (R=Et, nPr, nBu) were synthesized in a straightforward fashion by reducing R3PAuCl with NaBH4 in ethanol. The Au32 core comprises two shells, with the inner one constituting a tilted icosahedron and the outer one showing a distorted dodecahedral arrangement. The outer shell is completed by eight chloride atoms and twelve R3P groups. The inner icosahedron shows bond lengths typical for elemental gold while the distances of the gold atoms in the dodecahedral arrangement are in the region of aurophilic interactions. Quantum‐chemical calculations illustrate that the Jahn–Teller effect observed within the cluster core can be attributed to the electronic shell filling. The easily reproducible synthesis, good solubility, and high yields of these clusters render them perfect starting points for further research. Gold cluster triumvirate: Three gold clusters Au32(R3P)12Cl8 were synthesized, obtained in good yields in crystalline form, and structurally characterized. They show the same Jahn–Teller‐distorted core motif consisting of an Au12 icosahedron inside an Au20 dodecahedron, and differ only in the length of the alkyl chains of the respective phosphine ligands and their solubility properties. [ABSTRACT FROM AUTHOR]

Reducing (Ph3P)AuSC(SiMe3)3 with l-Selectride® gives the medium-sized metalloid gold cluster Au70S20(PPh3)12. Computational studies show that the phosphine bound Au-atoms not only stabilize the electronic structure of Au70S20(PPh3)12, but also behave as electron acceptors leading to auride-like gold atoms on the exterior. [ABSTRACT FROM AUTHOR]

The reduction of (Ph3P)AuCl with NaBH4 in the presence of HSC(SiMe3)3, leads to one of the largest metalloid gold clusters: Au108S24(PPh3)16 ( 1). Within 1 an octahedral Au44 core of gold atoms arranged as in Au metal is surrounded by 48 oxidized Au atoms of an Au48S24 shell, a novel building block in gold chemistry. The protecting Au48S24 shell is completed by additional 16 Au(PPh3) units, leading to a complete protection of the gold core. Within 1 the Au-Au distances get more molecular on going from the center to the ligand shell. Cluster 1 represents novel structural motives in the field of metalloid gold clusters which also are partly typical for metal atoms in metalloid clusters: M nR m ( n> m). [ABSTRACT FROM AUTHOR]

The increasing number of metalloid clusters, synthesized in the last couple of years, gives new insights into the formation process of metals or semi-metals. Metalloid clusters of the transition metals, especially the coinage metals are thereby of particular interest and the number of structurally characterized metalloid gold clusters has increased over the last decade. Most of these clusters are stabilized via aryl thiolate ligands. Herein, the synthesis and crystal structures of the lithium and potassium salts of the bulky SSi(SiMe3)3 ligand are presented together with the synthesis of suitable MI precursors ( M = Cu, Ag, Au) for further build-up reactions to metalloid clusters. [ABSTRACT FROM AUTHOR]

Three multi‐shell metalloid gold clusters of the composition Au32(R3P)12Cl8 (R=Et, nPr, nBu) were synthesized in a straightforward fashion by reducing R3PAuCl with NaBH4 in ethanol. The Au32 core comprises two shells, with the inner one constituting a tilted icosahedron and the outer one showing a distorted dodecahedral arrangement. The outer shell is completed by eight chloride atoms and twelve R3P groups. The inner icosahedron shows bond lengths typical for elemental gold while the distances of the gold atoms in the dodecahedral arrangement are in the region of aurophilic interactions. Quantum‐chemical calculations illustrate that the Jahn–Teller effect observed within the cluster core can be attributed to the electronic shell filling. The easily reproducible synthesis, good solubility, and high yields of these clusters render them perfect starting points for further research. Gold cluster triumvirate: Three gold clusters Au32(R3P)12Cl8 were synthesized, obtained in good yields in crystalline form, and structurally characterized. They show the same Jahn–Teller‐distorted core motif consisting of an Au12 icosahedron inside an Au20 dodecahedron, and differ only in the length of the alkyl chains of the respective phosphine ligands and their solubility properties. [ABSTRACT FROM AUTHOR]