Abstract

Electrochemical oxidation of the dicyano(2,3-naphthalocyanato)cobalt(III) anion ([Co(2,3-Nc)(CN)₂]⁻) yields electrically conducting crystals comprised of the Co(2,3-Nc)(CN)₂ neutral radicals and some crystal solvents. The oxidation of the potassium salt in acetonitrile gives Co(2,3-Nc)(CN)₂·CH₃CN, while that in a mixed solvent of acetonitrile/o-dichlorobenzene (DCB) gives Co(2,3-Nc)(CN)₂·2DCB. X-Ray structure analyses show that two- or three-dimensional π–π stacking interactions are achieved in these crystals. Compared with the phthalocyanine (Pc) derivatives this higher-dimensionality in the 2,3-Nc radical crystals, even with a large crystal solvent, arises from the linear extension of the π-conjugation system of Pc.