Aromatic S-Approach to Fluorinated Phenyl -Butyl Nitroxides.

The interaction of octafluorotoluene (), as well as pentafluorobenzonitrile () with -butylamine, followed by the oxidation of thus formed -butylanilines (,) with -chloroperoxybenzoic acid led to functionalized perfluorinated phenyl -butyl nitroxides [namely, 4-(--butyl(oxyl)amino)heptafluorotoluene () and 4-(--butyl(oxyl)amino)tetrafluorobenzonitrile ()] with nearly quantitative total yields. The molecular and crystal structures of nitroxide were proved by single crystal X-ray diffraction analysis. The radical nature of both nitroxides was confirmed by ESR data. The interaction of Cu(hfac) with the obtained nitroxides , gave corresponding -bis(1,1,1,5,5,5-hexafluoropentane-2,4-dionato-,')bis{4-(--butyl(oxyl)amino)perfluoroarene-}copper (II) complexes ([Cu(hfac)()] and [Cu(hfac)()]). X-ray crystal structure analysis showed square bipyramid coordination of a centrally symmetric Cu polyhedron with the axial positions occupied by oxygen atoms of the nitroxide groups. Magnetic measurements revealed intramolecular ferromagnetic exchange interactions between unpaired electrons of Cu(II) ions and paramagnetic ligands, with exchange interaction parameters reaching 53 cm.