Inclusion of anthraquinone derivatives by the cucurbit[7]uril host

Abstract

Two simple cationic anthraquinone derivatives were found to form stable complexes with the cucurbit[7]uril host, in which the anthraquinone residue is included by the host cavity. The corresponding equilibrium association constants were relatively low (K ∼10³ M⁻¹)—compared to those of other complexes formed by the same host—suggesting that anthraquinone is not an ideal guest. However, the electrochemical behavior of the guests is strongly affected by inclusion inside the host cavity.