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Updated: Apr 18, 2026

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Contrasting anion recognition behaviour exhibited by halogen and hydrogen bonding rotaxane hosts
Stuart P Cornes1, Charles H Davies, David Blyghton
1Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK. paul.beer@chem.ox.ac.uk.
Abstract:
A rotaxane host system containing a novel halogen bonding (XB) 5-iodo-1,2,3-triazole functionalised pyridinium motif, within its axle component, has been prepared via a ring closing metathesis reaction, using chloride as a template. Proton NMR titration experiments, in competitive 1 : 1 CDCl3-CD3OD solvent media, showed the XB rotaxane selectively bound halides over larger, more basic oxoanions. An all hydrogen bonding proto-triazole containing rotaxane analogue was also prepared, which in stark contrast demonstrated a reversal in the anion selectivity trend, with a preference for dihydrogen phosphate over the halides which is unprecedented for an interlocked host system.
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