Electron Transfer Driven Transformations of Transition Metal π-Complexes: Samarium(II) Iodide Mediated Coupling of Fluoroarene-Cr(CO)₃Complexes with Ketones

Abstract

Fluoro-substituted η6-arene tricarbonylchromium complexes react with aliphatic ketones in the presence of SmI2 and tBuOH under C-C bond formation to give the corresponding tertiary benzylic alcohols in up to 77% yield. Chlorobenzene-Cr(CO)3 exhibit a similar reactivity. The reactions proceed through attack of a ketyl radical to the complexed arene followed by single electron reduction of the 17 VE intermediate. The overall reaction parallels a nucleophilic aromatic substitution of fluoride (SNAr) and preferentially occurs in a meta-tele fashion.