Small Gold(I) and Gold(I)–Silver(I) Clusters by C−Si Auration

Abstract

Auration of o‐trimethylsilyl arylphosphines leads to the formation of gold and gold–silver clusters with ortho‐metalated phosphines displaying 3c–2e Au−C−M bonds (M=Au/Ag). Hexagold clusters [Au6L4](X)2 are obtained by reaction of (L−TMS)AuCl with AgX, whereas reaction with AgX and Ag2O leads to gold–silver clusters [Au4Ag2L4](X)2. Oxo‐trigold(I) species [Au3O]+ were identified as the intermediates in the formation of the silver‐doped clusters. Other [Au5], [Au4Ag], and [Au12Ag4] clusters were also obtained. Clusters containing PAu−Au−AuP structural motif display good catalytic activity in the activation of alkynes under homogeneous conditions.

Main Avenues in Gold Coordination Chemistry

“…Recently, heteronuclear clusters 126 and 127 presented also good catalytic activity in the addition of 1,3,5-trimethoxybenzene to 1,6-enyne at 25 °C under homogeneous conditions. 325 A particular fascinating aspect in this chemistry is the study of the chirality. The origin of the first chiral gold clusters could be attributed to Schaaff's work.…”

“…It is well-known that clusters display interesting properties due to the synergy effects combined from their subunits, the electrophilic Au­(I) atoms and the auxiliary base ligands. − Therefore, the efforts have been pushed to carefully tune the properties of the clusters, mainly related either with the cluster core or with the ligands attached to the gold atoms. Among the properties studied, special mention deserve the works based on the luminescence and biological activity of such structures. − However, the catalytic − properties and the possibility of using chiral clusters species − are less explored.…”

“…Later, trinuclear gold cluster supported by cyclic (alkyl)­(amino)­carbene ligands 124 and bimetallic [Au I 4 Ag I ] complex 125 were found active in the carbonylation reaction of aliphatic amines giving rise to ureas in good to excellent yields, reported by Bertrand and Echavarren, respectively. Recently, heteronuclear clusters 126 and 127 presented also good catalytic activity in the addition of 1,3,5-trimethoxybenzene to 1,6-enyne at 25 °C under homogeneous conditions …”

New cationic coinage metal complexes featuring silyl group functionalized phosphine: syntheses, structures and catalytic studies in alkyne–azide cycloaddition reactions

“…[9][10][11] Type II phosphines consisting of ortho-silylated groups and their transition metal complexes have been shown to exhibit enhanced solubility in various non-polar solvents which is in contrast to many typical aryl phosphine ligands. 4,[12][13][14] Additionally, the type II species have also been employed as mono-dentate ligands in coinage metal chemistry, 15 for instance gold(I) chloride complexes of type III [(II R ) AuCl] (R = Ph, Cy) and IV have been isolated. 15 Furthermore, the corresponding cationic complexes featuring trimetallic gold complexes of the type [{(II R )Au} 3 O]SbF 6 (V, R = Ph, Cy) have been isolated and structurally characterized.…”

“…4,[12][13][14] Additionally, the type II species have also been employed as mono-dentate ligands in coinage metal chemistry, 15 for instance gold(I) chloride complexes of type III [(II R ) AuCl] (R = Ph, Cy) and IV have been isolated. 15 Furthermore, the corresponding cationic complexes featuring trimetallic gold complexes of the type [{(II R )Au} 3 O]SbF 6 (V, R = Ph, Cy) have been isolated and structurally characterized. In a similar fashion, Shi and co-workers demonstrated the isolation of gold (I) chloride complexes of type III.…”