Cucurbit[7]uril‐Based Metal–Organic Rotaxane Framework for Dual‐Capture of Molecular Iodine and Cationic Potassium Ion

Metal–organic rotaxane frameworks (MORFs) attracted much attention in the past years for construction of intelligent functional materials. Herein, a one‐pot synthesis is reported of a three‐dimensional (3D) cucurbit[7]uril (Q[7])‐based MORF under hydrothermal conditions, namely Q[7]‐MORF‐1, formed by encapsulating the anionic benzoate moieties of the tricarboxylate ligand into the cavity of Q[7]. Furthermore, Q[7]‐MORF‐1 shows dual‐capture capacity for iodine and K+ selectively among the alkali metal ions. The captured molecular iodine is included in the cavity of Q[7] through halogen‐bonding interactions and the K+ cations are positioned at the carbonyl port of the Q[7] through K−O coordination interactions. Mighty MORFin: A novel 3D Q[7]‐based metal–organic rotaxane framework, with the anionic benzoate moieties of BTTA3− encapsulated in the cavity of Q[7] was obtained and exhibited capacity for the capture of iodine and K+ selectively among the alkali metal ions.