title: Chelated charge assisted halogen bonding enhanced halide recognition by a pyridinium-iodotriazolium axle containing [2]rotaxane.
abstract: Four halogen and hydrogen bonding rotaxane host systems featuring pyridinium bis-amide-iodotriazole/prototriazole and pyridinium bis-amide-iodotriazolium/prototriazolium axle components have been synthesized by CuAAC-mediated mono-stoppering chloride anion templation and post-rotaxanation methylation reactions. In competitive 45 : 45 : 10 CDCl3-CD3OD-D2O aqueous solvent media, the dicationic halogen bonding rotaxane displayed a notable enhanced binding affinity and marked selectivity for Br-over other halides and nitrate and dihydrogen phosphate oxoanions in contrast to an all hydrogen bonding counterpart which is attributed to chelated charge assisted halogen bonding interactions.
authors.affiliation: Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK. paul.beer@chem.ox.ac.uk.
authors.forename: Alexander E
authors.initials: AE
authors.lastname: Hess
authors.affiliation: Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK. paul.beer@chem.ox.ac.uk.
authors.forename: Paul D
authors.initials: PD
authors.lastname: Beer