title: A halogen-bonding bis-triazolium rotaxane for halide-selective anion recognition.
abstract: A systematic study on the anion-binding properties of acyclic halogen- and hydrogen-bonding bis-triazolium carbazole receptors is described. The halide-binding potency of halogen-bonding bis-iodotriazolium carbazole receptors was found to be far superior to their hydrogen-bonding bis-triazolium-based analogues. This led to the synthesis of a mixed halogen- and hydrogen-bonding rotaxane host containing a bis-iodotriazolium carbazole axle component. The rotaxane's anion recognition properties, determined by (1)H NMR titration experiments in a competitive aqueous solvent mixture, demonstrated the preorganised halogen-bonding interlocked host cavity to be halide-selective, with a strong binding affinity for bromide.
authors.affiliation: Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Rd, Oxford, OX1 3TA (UK).
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Mullaney
authors.forename: Benjamin E
authors.initials: BE
authors.lastname: Partridge
authors.forename: Paul D
authors.initials: PD
authors.lastname: Beer
keywords: anion binding; carbazoles; halogen bonding; host-guest systems; supramolecular chemistry