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Conformational Control of [2]Rotaxane by Hydrogen Bond
Yusuke Kawasaki1, Showkat Rashid1, Katsuhiko Ikeyatsu1
1Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan.
The Journal of Organic Chemistry
|April 7, 2022
Summary
Researchers synthesized novel rotaxanes using copper catalysis. Hydrogen bonding between the macrocycle and axle dictates the rotaxane
Area of Science:
- Supramolecular Chemistry
- Organic Synthesis
- Coordination Chemistry
Background:
- Rotaxanes are mechanically interlocked molecules with potential applications in molecular machines.
- Controlling the conformation of rotaxanes is crucial for their function.
- Macrocyclic components often play a key role in directing rotaxane structure.
Purpose of the Study:
- To synthesize a series of rotaxanes with diverse functional groups on the axle.
- To investigate the conformational behavior of these rotaxanes.
- To elucidate the role of intercomponent interactions in dictating rotaxane structure.
Main Methods:
- Oxidative dimerization of alkynes mediated by a macrocyclic phenanthroline-copper complex.
- Spectroscopic characterization (e.g., NMR, Mass Spectrometry).
- X-ray crystallographic analysis to determine molecular structure.
Main Results:
- Successful synthesis of [2]rotaxanes with varying axle functionalities.
- Detailed structural analysis revealing specific conformations.
- Identification of a key hydrogen bond interaction between the phenanthroline moiety and the axle's acidic proton.
Conclusions:
- The synthesized rotaxanes exhibit unique conformations influenced by their components.
- Hydrogen bonding is a significant factor in controlling rotaxane conformation.
- This study provides insights into the rational design of functional rotaxanes.
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