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Updated: May 27, 2025

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Amphoteric chalcogen-bonding and halogen-bonding rotaxanes for anion or cation recognition
Yuen Cheong Tse1, Andrew Docker1, Igor Marques2
1Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK.
Researchers developed novel host molecules capable of recognizing both charged cations and anions. This breakthrough utilizes the amphoteric nature of tellurium and iodine atoms for selective binding in supramolecular chemistry.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Chemical Recognition
Background:
- Growing need for host molecules to recognize charged species due to their biological and environmental importance.
- Existing methods often require distinct hosts for cations and anions.
Purpose of the Study:
- To demonstrate a proof of concept for a single host molecule binding both cations and anions.
- To explore the use of amphoteric atoms (tellurium, iodine) for dual charge recognition.
Main Methods:
- Synthesis of mechanically interlocked [2]rotaxane molecules.
- Chalcogen-bonding (ChB) and halogen-bonding (XB) interactions were investigated.
- 1H nuclear magnetic resonance (NMR) titration experiments.
- Computational density functional theory (DFT) studies.
Main Results:
- A library of ChB and XB [2]rotaxanes was synthesized and characterized.
- These rotaxanes function as multidentate hosts for both Lewis-acidic cation and Lewis-basic anion binding.
- Demonstrated selective binding of halide anions and metal cations by the same host structure.
Conclusions:
- Exploited the amphoteric character of tellurium and iodine atoms for simultaneous cation and anion recognition.
- Introduced a novel strategy in supramolecular host-guest chemistry.
- Opened a new avenue for designing adaptable molecular recognition systems.
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