Striking ligand-disproportionative Cl/aryl scrambling in a simple Au(iii) system. Solvent role, driving forces and mechanisms

Aryl rearrangements triggered by Cl- extraction from trans-[Au-III(Rf)(2)Cl-2](-) (Rf = C6F3Cl2-3,5), led quickly to a mixture of [Au(Rf)(3)(solv)], cis-[Au(Rf)(2)Cl(solv)] and [Au(Rf)Cl-2(solv)] (solv = OEt2, OH2). F-19 NMR and X-ray diffraction studies led us to identify the species present in solution and the role of the solvent in their formation, while DFT calculations confirm the thermodynamic basis of their evolution. Very different Rf-Rf coupling rates are found from (mu-Cl)(2)[cis-Au(Rf)(2)](2) or cis-[Au(Rf)(2)ClL] species (L = OEt2, NCMe, Cl-) depending on the coordination strength of the ligand or solvent in the fourth position.

Automated summary

Through experimental and computational methods, this study investigates aryl rearrangements triggered by Cl- extraction, examines the influence of solvent on the formation of gold complexes, and identifies the presence of species in solution. Different coupling rates are found depending on the coordination strength of ligands or solvents in the fourth position.