Aryl–Fluoride Bond-Forming Reductive Elimination from Nickel(IV) Centers

The treatment of pyridine- and pyrazole-ligated NiII σ-aryl complexes with Selectfluor results in C­(sp2)–F bond formation under mild conditions. With appropriate design of supporting ligands, diamagnetic NiIV σ-aryl fluoride intermediates can be detected spectroscopically and/or isolated during these transformations. These studies demonstrate for the first time that NiIV σ-aryl fluoride complexes participate in challenging C­(sp2)–F bond-forming reductive elimination to yield aryl fluoride products.