Halogen bonding rotaxanes for nitrate recognition in aqueous media
Sean W Robinson1, Paul D Beer1
1Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK. paul.beer@chem.ox.ac.uk.
Abstract:
Targeting the biologically and environmentally important nitrate anion, halogen bonding (XB) has been incorporated into three novel [2]rotaxane structural frameworks via an axle component containing covalently linked 3,5-bis-iodotriazole pyridine-pyridinium motifs. This has enabled the recognition of nitrate in aqueous media containing up to 90% water with equivalent binding affinity to chloride, illustrating the potency of XB for anion recognition in highly competitive aqueous solvent mixtures.
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