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C3-symmetrical self-assembled structures investigated by vibrational circular dichroism
Maarten M J Smulders1, Thierry Buffeteau, Dominique Cavagnat
1Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands.
Chirality
|May 14, 2008
Summary
Vibrational circular dichroism (VCD) spectroscopy can determine the chirality of supramolecular polymers in dilute solutions. This study confirms right-handed helical structures formed by discotic molecules via hydrogen bonding.
Area of Science:
- Supramolecular Chemistry
- Spectroscopy
- Chirality Studies
Background:
- Investigating chirality in complex supramolecular systems is challenging.
- Discotic molecules can self-assemble into ordered structures.
- Hydrogen bonding plays a crucial role in supramolecular assembly.
Purpose of the Study:
- To demonstrate the utility of VCD spectroscopy for analyzing supramolecular chirality in dilute solutions.
- To determine the handedness and structural features of self-assembled discotic molecules.
- To correlate spectroscopic findings with theoretical calculations and X-ray diffraction data.
Main Methods:
- Vibrational Circular Dichroism (VCD) spectroscopy
- Infrared (IR) spectroscopy
- Electronic spectroscopy
- Density Functional Theory (DFT) calculations
Main Results:
- VCD spectroscopy successfully probed chiral supramolecular polymeric systems at low concentrations (10(-3) M).
- Chiral C(3)-symmetrical discotic molecules self-assembled into right-handed helical supramolecular columnar stacks.
- DFT calculations supported the observed right-handed chirality and nonplanar carbonyl orientation.
Conclusions:
- VCD spectroscopy is a viable method for studying chirality in dilute supramolecular solutions.
- The self-assembly of trialkylbenzene-1,3,5-carboxamide derivatives leads to predictable helical structures.
- Spectroscopic and computational methods confirm the chiral arrangement in these supramolecular polymers.
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