N‐Doping of Polyaromatic Capsules: Small Cavity Modification Leads to Large Change in Host–Guest Interactions

To gain insight into the host functions of a nanocavity encircled by both polyaromatic panels and heteroatoms, nitrogen‐doped polyaromatic capsules were successfully synthesized from metal ions and pyridine‐embedded, bent anthracene‐based ligands. The new capsules display unique host–guest interactions in the isolated cavities, which are distinct from those of the undoped analogues. Besides the inclusion of Ag+ ions, the large absorption change of fullerene C60 and altered emission of a BODIPY dimer are observed upon encapsulation by the present hosts. Moreover, the N‐doped capsule exhibits specific binding ability toward progesterone and methyltestosterone, known as a natural female and synthetic male hormone, respectively, in water. Nanospace functions: Nitrogen‐doped polyaromatic capsules were synthesized from metal ions and pyridine‐embedded, bent anthracene‐based ligands. These capsules display unique host–guest interactions, distinct from those of the undoped analogues. Besides the inclusion of Ag+ ions, an absorption change of fullerene C60 and altered emission of a BODIPY dimer are observed upon encapsulation. Moreover, the N‐doped capsule exhibits specific binding abilities toward a natural female and synthetic male hormones.