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Updated: May 17, 2026
10:39
Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction
Published on: August 23, 2018
Host-guest complexes between cryptophane-C and chloromethanes revisited
Z Takacs1, M Soltesova, J Kowalewski
1Arrhenius Laboratory, Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91, Stockholm, Sweden.
Magnetic Resonance in Chemistry : MRC
|November 8, 2012
Summary
This study reveals how cryptophane-C binds dichloromethane and chloroform. Molecular dynamics and computational analysis show that host conformation and guest movement are key to this molecular recognition process.
Area of Science:
- Supramolecular Chemistry
- Molecular Recognition
- Computational Chemistry
Background:
- Cryptophane-C features two cyclotribenzylene caps with methoxy substituents.
- Three OCH(2)CH(2)O linkers connect the caps in an anti arrangement.
Purpose of the Study:
- Investigate host-guest complexes of cryptophane-C with dichloromethane and chloroform.
- Elucidate the dynamic processes governing molecular recognition in these systems.
Main Methods:
- Nuclear Magnetic Resonance (NMR) spectroscopy (variable temperature, exchange spectroscopy, relaxation experiments).
- Density Functional Theory (DFT) calculations.
- Line-shape analysis.
Main Results:
- Observed dynamic processes including guest exchange and host conformational transitions.
- Identified gauche+2 and gauche-2 conformations of the linkers via cross-relaxation.
- Characterized chloroform guest mobility within the cryptophane-C cavity.
Conclusions:
- Detailed molecular recognition mechanism elucidated through combined experimental and computational data.
- Conformational selection is the primary mode of interaction between cryptophane-C and its guests.
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