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Published on: November 9, 2019
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Boronic ester-templated pre-rotaxanes as versatile intermediates for rotaxane endo-functionalisation
Jingjing Yu1, Marius Gaedke1, Satyajit Das1
1KTH Royal Institute of Technology, Department of Chemistry Teknikringen 30 10044 Stockholm Sweden fresch@kth.se.
Chemical Science
|November 21, 2024
Summary
We synthesized [2]rotaxanes using dynamic covalent boronic ester templates and vicinal diols. The boronic ester enabled versatile post-functionalization of the rotaxane structure for diverse applications.
Area of Science:
- Supramolecular Chemistry
- Organic Synthesis
- Materials Science
Background:
- Rotaxanes are mechanically interlocked molecules with unique properties.
- Developing efficient and versatile synthesis methods for functionalized rotaxanes is crucial.
Purpose of the Study:
- To report a novel method for synthesizing [2]rotaxanes from vicinal diols.
- To demonstrate the utility of boronic ester templates for post-functionalization of rotaxanes.
Main Methods:
- Dynamic covalent chemistry utilizing boronic ester templates.
- Condensation of a boronic acid pincer ligand with a diol-containing thread.
- Ring-closing metathesis to form pre-rotaxane architecture.
- Advanced NMR spectroscopy and mass spectrometry for isomer characterization.
Main Results:
- Successful synthesis of [2]rotaxanes from vicinal diols.
- Establishment of a pre-rotaxane intermediate in equilibrium with its hydrolyzed form.
- Demonstration of diverse post-functionalization strategies via the boronic ester handle.
- Obtained endo-functionalized [2]rotaxanes through oxidation, protodeboronation, and cross-coupling reactions.
Conclusions:
- Boronic ester templates offer a powerful platform for rotaxane synthesis and functionalization.
- The developed method provides access to a variety of endo-functionalized [2]rotaxanes.
- This work expands the synthetic toolbox for constructing complex molecular architectures.
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