Host-guest chemistry of an ion-complexation by macrocyclic multidentate Lewis acids
In contrast to the extraordinary achievements of cation complexation in host-guest chemistry, only recently has anion complexation by compounds containing electrondeficient atoms such as boron, mercury, tin and silicon received attention. We here present a new class of carborane-supported macrocyclic multidentate Lewis acid hosts which bind nucleophilic species to form isolable host-guest complexes having unprecedented structures. The synthesis and structural characterization of these complexes will be discussed along with their solution chemistry studied by 1NHg NMR spectroscopy. The extension of this chemistry to the synthesis of novel supramolecular aggregates which contain the Lewis acid hosts combined with polyhedral borane anions of congruent symmetry will be discussed.