title: Control of Cu(II) and Cu(III) states in N-confused porphyrin by protonation/deprotonation at the peripheral nitrogen.
abstract: The square-planar structure of a diamagnetic Cu(III) complex of tetrakis(pentafluorophenyl)-substituted N-confused porphyrin was elucidated by X-ray diffraction analysis. The facile interconversion between Cu(II) (1) and Cu(III) (2) complexes was achieved by chemical oxidation/reduction, and the Cu(III)/Cu(II) redox potential was controlled by adding anions through the hydrogen-bonding interaction to the peripheral NH.