Cationic Gold(I) Phosphanyl Thiolates: Aurophilic Interactions in the Solid State and in Solution

The aggregation states in solution of gold(I) cationic complexes of the formula [Au2(StBu)(L2)][BF4] (L = PMe3, PEt3, PtBu3, PPh3; L2 = dppm, dppe) were studied by MS (ESI) and DOSY spectroscopy. These compounds are tetranuclear in the solid state with a core of four gold centres bound together by aurophilic interactions and bridging thiolato groups. Some of these tetranuclear systems are maintained intact in solution depending on the phosphane steric properties or denticity