Metal–Ligand Cooperative C–H Bond Formation by Cyclopentadienone Platinum Complexes

C–H bond cleavage and formation is one of the most essential elementary reactions in organic chemistry. Herein, a heterolytic sp3 C–H bond reductive elimination from hydroxyCp dimethylplatinum­(IV) B is reported. Protonation of cyclopentadienone dimethylplatinum­(II) A afforded B via the protonation of the ligand. Successive C–H bond formation from the C anion of the methyl group and the H cation of the hydroxyCp group was observed in the presence of carboxylic acids or hydrogen chloride. The reaction was accompanied by the concurrent reduction of Pt­(IV) to Pt­(II). Experimental and theoretical investigations suggested that the mechanism for the C–H bond formation was acid-mediated metal–ligand cooperative outer-sphere reductive elimination.