Oxidation State-Dependent Intramolecular Electronic Interaction of Carbazole-Based Azacyclophanes with 9,10-Anthrylene Units.

We designed an azacyclophane comprising 3,6-substituted carbazole and 9,10-anthrylene units to investigate the unique electronic properties of the oxidation states arising from the presence of multiple oxidizable azacyclophane. This compound and its analogue containing 1,4-phenylene in substitution of 9,10-anthrylene units were synthesized by Buchwald-Hartwig coupling reactions. Cyclic voltammograms of both the 9,10-anthrylene and 1,4-phenylene derivatives exhibited four quasi-reversible oxidation processes. The absorption spectra of the oxidation states of the 9,10-anthrylene derivative exhibited broad absorption bands in the near-infrared region arising from charge-resonance and intramolecular charge-transfer interactions. The photophysical and electrochemical properties of the 9,10-anthrylene derivative were compared with those of the corresponding 1,4-phenylene derivative on the basis of theoretical calculations to evaluate the intramolecular electronic interactions.