Abstract Fluorine-containing N-arylhydroxylamines have been obtained by the action of hydroxylamine or its N-and O-derivatives on polyfluorinated benzenes and pentafluoropyridine. The influence of fluorine atoms on the reactivity of hydroxylamino group has been investigated. The reaction of N-polyfluoroarylhydroxylamines with aldehydes has been shown not to occur, whereas their reaction with nitrosobenzenes leads to ...