Oxidatively Induced C-H Activation at High Valent Nickel

This communication describes a series of oxidatively induced intramolecular arene C-H activation reactions of Ni-II model complexes to yield Ni-IV sigma-aryl products. These reactions proceed within to min at room temperature, which represents among the mildest conditions reported for C-H cleavage at a Ni center. A combination of density functional theory and preliminary experimental mechanistic studies implicate a pathway involving initial 2e(-) oxidation of the Ni-II starting materials by the transfer reagent N-fluoro-2,4,6-trimethylpyr-idinium triflate followed by triflate-assisted C-H cleavage at Ni-IV to yield the products.