Unexpected Outcomes of the Oxidation of (Pentafluorophenyl)triphenylphosphanegold(I)

Redox gold(I)/gold(III) catalytic cycles have been proposed as the productive mechanistic manifold in a number of gold mediated CC and CX bond forming reactions. These transformations rely on the use of stoichiometric oxidants such as iodonium salts and Selectfluor. We have studied the oxidation of electron deficient [Au(C6F5)(PPh3)] (1) in the presence of such oxidizing agents. The reaction of 1 with PhI(OAc)2 afforded cis-[Au(C6F5)2Cl(PPh3)] (3), which seemed to be produced by oxidation of the starting complex followed by a gold(I)/gold(III) transmetalation process or ligand exchange. The reaction of 1 with Selectfluor afforded an unprecedented gold(I)gold(III) complex [Au(PPh3)2][Au(C6F5)4] (7).