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Updated: Mar 17, 2026
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Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
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Recognition of Multiple Methyl Groups on Aromatic Rings by a Polyaromatic Cavity
Masahiro Yamashina1, Sho Matsuno1, Yoshihisa Sei1
1Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|July 22, 2016
Summary
This study shows how a nanometer-sized coordination capsule recognizes the number of methyl groups on aromatic compounds in water. Specific CH3-polyaromatic interactions within the capsule drive this selective recognition.
Area of Science:
- Supramolecular Chemistry
- Organic Chemistry
- Nanotechnology
Background:
- Methyl groups are typically considered to have weak interactions.
- Selective recognition of small organic substituents is challenging.
- Coordination capsules offer confined environments for molecular interactions.
Purpose of the Study:
- To investigate the selective recognition of methyl groups on aromatic compounds.
- To explore the role of a polyaromatic coordination capsule in molecular recognition.
- To understand the driving forces behind selective guest-host interactions in water.
Main Methods:
- Synthesis of a 1 nm-sized polyaromatic coordination capsule.
- Competitive encapsulation experiments with benzene and xanthine derivatives.
- X-ray crystallographic analysis to elucidate binding modes.
Main Results:
- The coordination capsule selectively recognized the number of methyl groups on aromatic guests.
- Multiple guest-host CH3-polyaromatic interactions were identified as key.
- High selectivity was achieved in aqueous solution.
Conclusions:
- Polyaromatic coordination capsules can achieve selective recognition of methyl group numbers.
- Confined nanospace enhances weak CH3-polyaromatic interactions.
- This work provides insights into designing selective molecular recognition systems.
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