Aggregation of Dinuclear Cations [{Au(PR 3 )} 2 (μ‐OH)] + into Dimers Induced by Polyoxometalate (POM) Template Effects

Intercluster compounds, [{(Au{P( p ‐ X Ph) 3 }) 2 (μ‐OH)} 2 ][α‐SiMo 12 O 40 (Au{P( p ‐ X Ph) 3 }) 2 ] · n EtOH [ X = F ( 1 ), Cl ( 2 )] were synthesized by polyoxometalate (POM)‐mediated clusterization, and were unequivocally characterized by X‐ray crystallography, elemental analysis, thermogravimetric and differential thermal analysis (TG/DTA), Fourier transform infrared (FT‐IR), solid‐state cross‐polarization magic‐angle‐spinning (CPMAS) 31 P nuclear magnetic resonance (NMR), and solution ( 1 H, 31 P{ 1 H}) NMR spectroscopy. The “dimer‐of‐dinuclear phosphanegold(I) cation”, i.e., [{(Au{P( p ‐ X Ph) 3 }) 2 (μ‐OH)} 2 ] 2+ was formed by the self‐assembly of dinuclear phosphanegold(I) cations, i.e., [(Au{P( p ‐ X Ph) 3 }) 2 (μ‐OH)] + , through inter‐cationic aurophilic interactions as the crossed‐edge arrangement (or tetrahedral Au 4 structure) for 1 , while as the parallel‐edge arrangement (or rectangular Au 4 structure) for 2 . The latter arrangement was first attained only by assistance of the POM. The POM anions in 1 and 2 contained two mononuclear phosphanegold(I) cations, i.e., [Au{P( p ‐ X Ph) 3 }] + , linked to the OMo 2 oxygen atoms of edge‐sharing MoO 6 octahedra. In the solution 31 P{ 1 H} NMR of 1 and 2 , we observed single signals due to the rapid exchange of the phosphanegold(I) units. This shows that the OMo 2 oxygen atoms of edge‐sharing MoO 6 octahedra in the Keggin POM act as multi‐centered active binding sites for the formation of [{(Au{P( p ‐ X Ph) 3 }) 2 (μ‐OH)} 2 ] 2+ .