Functionalization of non-activated C–H bonds in ketones and imines with HF/SbF5/CCl4

Reaction of cyclic ketones and imines in HF/SbF5 in presence of CCl4 yield hydroxy or fluoroderivatives, hydride abstraction occurring at a site located far from the functional group. Whereas ketones yield only hydroxy derivatives, through cyclic carboxonium ion, imines , N-protonated in the media conditions give only fluoroderivatives , , respectively, after quenching with HF–pyridine. Ring contraction is operative when starting from large membered ring ketones and , and imine , leading to a mixture of hydroxy or fluoro cyclohexanones and/or cycloheptanones.