title: Anion recognition and anion-mediated self-assembly with thiourea-functionalised fused [3]polynorbornyl frameworks.
abstract: Three conformationally preorganised host molecules based on the [3]polynorbornyl framework and incorporating di-urea receptors were synthesised and their interaction with a series of anions investigated by (1)H NMR spectroscopy. A high affinity of each host molecule for dihydrogenphosphate (H(2)PO(4)(-)) and dihydrogenpyrophosphate (H(2)P(2)O(7)(2-)) was identified. In addition to binding to the urea receptors of the host molecules, evidence for an interaction involving the non-polar C-H groups within the binding cavity of the framework and guest anions was also discovered. Furthermore, an unusual 2 : 1 host-to-anion stoichiometry was indicated when binding H(2)P(2)O(7)(2-), and a model for the anion-mediated self-assembly of this complex species is proposed.
authors.affiliation: School of Life and Environmental Sciences, Deakin University, Waurn Ponds, Australia. thefef@deakin.edu.au
authors.forename: Frederick M
authors.initials: FM
authors.lastname: Pfeffer
authors.forename: Paul E
authors.initials: PE
authors.lastname: Kruger
authors.forename: Thorfinnur
authors.initials: T
authors.lastname: Gunnlaugsson