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We present a series of new intermetalloid clusters (R3P)CuGe9((Hyp)3, (R=Me, Et, iPr, nBu, tBu) (Hyp=Si(SiMe3)3) (R3P)AuGe9(Hyp)3MGe9(Hyp)3 (R=Ph, Me; M=Au, Cu). In conjunction with already known clusters, these give new insights into the bonding situation of metal bridged Ge9 clusters as well as a better understanding of the formation of these clusters. Additionally, the intermetalloid clusters with the smallest phosphine PMe3 show new bonding motives. [ABSTRACT FROM AUTHOR]

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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]

Die Reduktion von (Ph3P)AuCl mit NaBH4 in Gegenwart von HSC(SiMe3)3 führt zu einem der größten bisher beschriebenen metalloiden Goldcluster: Au108S24(PPh3)16 ( 1). In 1 sind die Goldatome im zentralen oktaedrischen Au44-Kern wie in metallischem Gold angeordnet und von 48 oxidierten Goldatomen einer Au48S24-Schale, einem neuartigen Baustein in der Goldchemie, umgeben. Die schützende Au48S24-Schale wird durch 16 zusätzliche Au(PPh3)-Einheiten abgeschlossen, was zu einer kompletten Abschirmung des Goldkerns führt. In 1 werden die Au-Au-Abstände von innen nach außen stärker molekular. 1 zeigt neue Strukturmotive im Bereich metalloider Goldcluster, die zum Teil jedoch typisch für Metallatome in metalloiden Clustern [MnRm (n>m)] sind. [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]

Drei mehrschalige metalloide Goldcluster der Zusammensetzung Au32(R3P)12Cl8 (R=Et, nPr, nBu) wurden über die unkomplizierte Syntheseroute der Reduktion von R3PAuCl mit NaBH4 in Ethanol hergestellt. Der Au32‐Kern setzt sich aus zwei Schalen zusammen; die innere besteht dabei aus einem schiefen Ikosaeder und die äußere aus einem verzerrten Dodekaeder. Die äußere Schale wird von acht Chloratomen und zwölf R3P‐Gruppen abgeschlossen. Während die Gold‐Gold‐Abstände des zentralen Ikosaeders im Größenbereich von elementarem Gold sind, sind die Bindungsabstände der Goldatome im umgebenden Dodekaeder im Bereich aurophiler Wechselwirkungen. Quantenchemische Rechnungen verdeutlichen, dass die beobachtete Jahn‐Teller‐Verzerrung des Clusterkerns auf einen elektronischen Schalenabschluss zurückzuführen ist. Die einfache Reproduzierbarkeit der Cluster, gute Löslichkeit und hohe Ausbeute an kristalliner Substanz sind ideale Voraussetzungen für weitere Untersuchungen. Goldcluster‐Triumvirat: Drei Goldcluster der Formel Au32(R3P)12Cl8 wurden synthetisiert und strukturell charakterisiert. Sie zeigen das gleiche Jahn‐Teller‐verzerrte Kernmotiv, ein Au12‐Ikosaeder, umgeben von einem Au20‐Pentagondodekaeder. Die Cluster unterscheiden sich in der Länge der Alkylgruppen der Phosphane und in ihrer Löslichkeit in diversen Lösungsmitteln und überzeugen durch ihre einfache Synthese und gute Ausbeute in reiner kristalliner Form. [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]

We present a series of new intermetalloid clusters (R3P)CuGe9((Hyp)3, (R=Me, Et, iPr, nBu, tBu) (Hyp=Si(SiMe3)3) (R3P)AuGe9(Hyp)3MGe9(Hyp)3 (R=Ph, Me; M=Au, Cu). In conjunction with already known clusters, these give new insights into the bonding situation of metal bridged Ge9 clusters as well as a better understanding of the formation of these clusters. Additionally, the intermetalloid clusters with the smallest phosphine PMe3 show new bonding motives. [ABSTRACT FROM AUTHOR]