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Updated: Mar 17, 2026
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
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Halides with Fifteen Aliphatic C-H···Anion Interaction Sites
Genggongwo Shi1,2, Zahra Aliakbar Tehrani1, Dongwook Kim1
1Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea.
Scientific Reports
|July 23, 2016
Summary
Hydrophobic aliphatic C-H groups can exclusively bind anions, challenging previous assumptions. This study reveals detailed X-ray structures of such novel anion-recognition complexes.
Area of Science:
- Supramolecular Chemistry
- Organic Chemistry
- Crystallography
Background:
- Aliphatic C-H···anion interactions are typically weak.
- Anion binding usually requires stronger interaction sites.
Purpose of the Study:
- To demonstrate exclusive anion binding by hydrophobic aliphatic C-H groups.
- To characterize the structural and electronic features of these interactions.
Main Methods:
- X-ray crystallography of organic crystals.
- Analysis of imidazolium-based scaffolds and tetraalkylammonium complexes.
Main Results:
- Exclusive binding of a chloride anion by fifteen hydrophobic aliphatic C-H groups was observed.
- The interaction forms a near-spherical dipole layer shell structure around the anion.
- No additional supporting interactions or binding sites were found.
Conclusions:
- Hydrophobic aliphatic C-H groups can serve as effective anion binding sites.
- These interactions are driven by electrostatic charge layering around the anion.
- Such binding motifs may be more common than previously thought.
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