Gold Complexes with Difunctional Perfluoroalkyl Chains: Quantifying the Energy of Aurophilic Interactions in Flexible Open-Chain Complexes.

The first binuclear AuI compounds containing bridging (CF2 )n chains (n=4, 6, 8) and AuIII metallaperfluorocyclopentanes have been obtained by photoinitiated reactions of LAuMe (L=PPh3 , PMe3 , PCy3 , or IPr) with α,ω-diiodoperfluorocarbons. Complexes LAu(CF2 )4 AuL present an unusual looped structure stabilized by an aurophilic interaction for L=PMe3 , PPh3 , and PCy3 . The study of their dynamic behaviour has provided new insights about the strength of aurophilic interactions in solution, allowing quantification of the energy of a single Au⋅⋅⋅Au interaction.