Carbon–Oxygen Bond Forming Reductive Elimination from Cycloplatinated(IV) Complexes

The synthesis of the two cycloplatinated­(IV) complexes [PtMe­(OAc)2(C∧N)­(H2O)] (C∧N = 2-phenylpyridinate (2a), benzo­[h]­quinolate, 2b) by reaction of [PtMe­(C∧N)­(SMe2)] with PhI­(OAc)2 is described. Complexes 2 undergo carbon–oxygen bond forming reductive elimination instead of C–C reductive elimination to produce MeOAc as protected methanol. The kinetics and mechanism of both Pt–O bond formation and C–O reductive elimination have been experimentally and theoretically investigated. The results suggest that formation of methyl acetate proceeds via nucleophilic attack of the dissociated acetate ligand at the methyl group carbon in a cationic five-coordinate intermediate cycloplatinated­(IV) complex.