A Unique Fluoride Nanocontainer: Porous Molecular Capsules Can Accommodate an Unusually High Number of Rather Labile Fluoride Anions

The present work refers to the challenging issue of fluoride anion recognition/binding in water by taking advantage of the unique possibilities offered by the porous molecular nanocontainers of the {Mo-132} Keplerate type allowing the study of a variety of new phenomena. Reaction of the highly reactive carbonate-type capsule with aqueous HF results in the release of carbon dioxide and integration of an unprecedentedly large number of fluoride anions-partly as coordinated ligands at both the pentagonal units and the linkers, partly as a disordered water/fluoride assembly inside the cavity. The internal assembly and some of the fluoride ligands are easily released, which provides interesting options for future studies regarding coordination chemistry and catalysis under confined conditions.