Oxidative Rearrangement in Gold Organometallics

The one-electron oxidizing agent [NO]­PF6 was reacted with Bu4N­[Au­(C6X5)2] (X = F, Cl) complexes in CH3CN. The gold­(III) complexes [Au­(C6F5)3(CH3CN)] and cis-[Au­(C6Cl5)2(CH3CN)2]­PF6 were synthesized by the oxidation of gold­(I) to gold­(III) with the concomitant ligand rearrangement “oxidative rearrangement”. The supramolecular crystal packing in the perfluorinated aryl gold­(III) complex is dictated by the notably short C­(sp2)–F···H­(CH3CN) bond distance. The [Au­(C6Cl5)2(CH3CN)2]­PF6 complex exhibits antisymbiosis, displaying equal ligands in the cis position. The electrochemical oxidation of Bu4N­[Au­(C6X5)2] (X = F, Cl) complexes in CH3CN showed two irreversible peaks at 0.71 and 1.21 V (X = F) and at 0.65 and 0.91 V (X = Cl) vs Ag/AgCl.