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 σ-aryl products. These reactions proceed within 10 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 F⁺ transfer reagent N-fluoro-2,4,6-trimethylpyridinium triflate followed by triflate-assisted C-H cleavage at Ni^IV to yield the products.