Charge transfer interactions of cyclobis(azopyridinium-phenylene) and hydroquinone derivatives

Tetracationic cyclophanes and a [2]-catenane consisting of cyclobis(azopyridinium-p-phenylene) were synthesized via the template-directed synthesis. The charge transfer transitions and stability constants for supramolecular complexes with hydroquinone derivatives were evaluated by using visible spectroscopy and spectroscopic titration.