A porphyrin nanochannel: formation of cationic channels by a protonated saddle-distorted porphyrin and its inclusion behavior

A highly saddle-distorted dodecaphenylporphyrin dication (H4DPP^2+) was revealed by X-ray crystallography to form positively charged porphyrin nanochannels which were 1 nm in diameter; chloride anion and redox-active hydroquinone could be incorporated in the channels.