Aerobic oxidation-induced virtual radical coupling of mixed-metal PtRh2 trinuclear complexes accompanied by the formation of a Rh–Rh bond

A mixed-metal Pt^IIRh^I₂ trinuclear complex with triply bridging sulfide ligands, generated by the reaction of a Rh(I) nbd complex with a bis(hydrosulfido) Pt(II) complex bearing a bisNHC ligand, is oxidized under aerobic conditions to give a diamagnetic hexanuclear cluster accompanied by the formation of a Rh^II–Rh^II bond.

An Osaka Metropolitan University team has demonstrated unprecedented virtual radical coupling of mixed-metal trinuclear complexes via interunit metal–metal bond formation to afford a hexanuclear cluster induced by aerobic oxidation. The electrochemical and chemical redox behavior of the hexanuclear cluster was also investigated, showing that the cluster dissociates into two trinuclear complexes upon reduction and is regenerated by oxidation of the trinuclear complex.