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Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Dimerization control in the self-assembly behavior of copillar[5]arenes bearing ω-hydroxyalkoxy groups
Luzhi Liu1, Lingyun Wang, Changchun Liu
1School of Chemistry and Chemical Engineering, State Key Lab of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510641, China.
The Journal of Organic Chemistry
|September 25, 2012
Summary
Two novel copillar[5]arenes were synthesized. One with a 6-hydroxyhexyloxy group showed reversible self-assembly, controllable by external factors, unlike the shorter chain analog.
Area of Science:
- Supramolecular Chemistry
- Organic Synthesis
- Materials Science
Background:
- Pillar[5]arenes are macrocyclic compounds known for their host-guest properties.
- Functionalization of pillararenes can alter their self-assembly behavior.
- Understanding self-assembly is crucial for designing novel functional materials.
Purpose of the Study:
- To synthesize novel copillar[5]arenes with ω-hydroxyalkoxy groups.
- To investigate the self-assembly properties of these new compounds.
- To explore the influence of side-chain length on self-assembly behavior.
Main Methods:
- Synthesis of copillar[5]arene derivatives.
- (1)H NMR spectroscopy for structural and self-assembly analysis.
- Specific viscosity measurements to study aggregation.
- X-ray diffraction for structural characterization.
Main Results:
- Two novel copillar[5]arenes with varying hydroxyalkoxy chain lengths were successfully synthesized.
- Copillar[5]arene 2b (6-hydroxyhexyloxy group) demonstrated reversible self-assembly into self-inclusion monomers and hugging dimers.
- This reversible self-assembly in 2b was tunable via solvent, temperature, guest molecules, and hydrogen bonding.
- Copillar[5]arene 2a (4-hydroxybutyloxy group) did not exhibit similar self-assembly behavior.
Conclusions:
- The length of the ω-hydroxyalkoxy side chain significantly impacts the self-assembly properties of copillar[5]arenes.
- Longer side chains can promote reversible self-assembly through specific interactions.
- Copillar[5]arene 2b serves as a model for stimuli-responsive supramolecular systems.
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