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Lyotropic liquid crystallinity in mixed-tautomer Schiff-base macrocycles
Jian Jiang1, Ronald Y Dong2, Mark J MacLachlan1
1Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1. mmaclach@chem.ubc.ca.
Chemical Communications (Cambridge, England)
|September 25, 2015
Summary
New Schiff-base macrocycles featuring keto-enamine and enol-imine tautomers were synthesized. These compounds form host-guest complexes and exhibit unexpected lyotropic liquid crystal behavior in organic solvents.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Organic Synthesis
Background:
- Schiff-base macrocycles are versatile molecular architectures with diverse applications.
- Tautomerism in macrocyclic systems can lead to unique chemical and physical properties.
Purpose of the Study:
- To synthesize novel Schiff-base macrocycles incorporating both keto-enamine and enol-imine tautomers.
- To investigate the host-guest complexation abilities of these new macrocycles.
- To explore the self-assembly and material properties of these compounds.
Main Methods:
- Synthesis of Schiff-base macrocycles via condensation reactions.
- Characterization using spectroscopic techniques (NMR, IR, Mass Spectrometry).
- Host-guest complexation studies with organic cations.
- Analysis of liquid crystalline behavior in organic solvents.
Main Results:
- Successful synthesis and characterization of novel macrocycles containing dual tautomeric forms.
- Demonstrated ability of macrocycles to form stable host-guest complexes with organic cations.
- Unexpected observation of lyotropic liquid crystalline phase in solvents like chloroform and toluene.
Conclusions:
- The synthesized Schiff-base macrocycles represent a new class of functional molecules.
- The combination of tautomers within the macrocycle influences its complexation and self-assembly properties.
- These findings open avenues for developing new materials with tunable properties for molecular recognition and advanced applications.
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