Intermolecular Oxidative Addition of Aryl Halides to Platinum(II) Alkyl Complexes

We report a well-defined example of intermolecular aryl halide oxidative addition (OA) to Pt(II). Complexes of the type (IMes)PtMe2(L) and (IMes′)PtMe(L) (L = SMe2, pyridine; IMes = N,N-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene; IMes′ = cyclometalated IMes) undergo intermolecular OA of phenyl iodide (PhI) at 60 °C, producing toluene via reductive elimination from a proposed Pt(IV) phenyl species. Isolation of a model Pt(IV) OA product provides evidence for a Pt(II)/Pt(IV) pathway. The OA of PhI is not limited to Pt(II) IMes complexes; analogous reactions also proceed with phosphine-ligated Pt(II) dialkyl complexes, demonstrating that this reaction is feasible for a variety of electron-rich Pt(II) complexes bearing labile ligands.