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Updated: Apr 28, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Halide selective anion recognition by an amide-triazolium axle containing [2]rotaxane
Nicholas G White1, Ana R Colaço, Igor Marques
1Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK. paul.beer@chem.ox.ac.uk.
Abstract:
A new rotaxane containing the 3-amido-phenyl-triazolium group incorporated into the interlocked structure's axle component has been prepared by a chloride anion templated clipping strategy. Proton NMR titration experiments reveal that the interlocked host displays a high degree of halide anion recognition in competitive 1 : 1 CDCl3-CD3OD solvent mixture. Chloride and bromide anions are bound strongly and selectively, with negligible complexation of the larger, more basic oxoanions, acetate and dihydrogen phosphate being observed. Density functional theory calculations on the related axle motifs 3-amido-phenyl-triazolium, pyridinium bis-triazole and pyridinium bis-amide were performed, and indicate that the new rotaxane axle motif displays much weaker oxoanion binding than the pyridinium based systems.
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