[28]Hexaphyrin derivatives for anion recognition in organic and aqueous media.

Hexaphyrin-based anion chemosensors are reported for the first time. The meso-hexakis(ethylenediamine)-substituted [28]hexaphyrins 2 and 3 revealed strong affinity for F(-), AcO(-) and H2PO4(-). Adsorption constants in aqueous media were determined on a gold piezoelectric crystal coated with 2 and 3. (1)H NMR titrations and molecular dynamics simulations showed the main interactions between hosts and guests.