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Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
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Twist sense control in terminally functionalized ortho-phenylenes.
Gopi Nath Vemuri1, Rathiesh R Pandian1, Brian J Spinello1
1Department of Chemistry & Biochemistry , Miami University , Oxford , OH 45056 , USA .
Chemical Science
|December 14, 2018
Summary
Chiral substituents on achiral aromatic foldamers control helix handedness. This study reveals "ambidextrous" substituents that induce opposite twist senses, offering new control over molecular folding.
Area of Science:
- Supramolecular Chemistry
- Organic Chemistry
- Materials Science
Background:
- Abiotic foldamers often adopt helical structures from achiral units.
- Chiral substituents can influence foldamer helix handedness.
- Controlling foldamer twist sense is key for molecular recognition and self-assembly.
Purpose of the Study:
- Investigate chiral induction in ortho-phenylene foldamers.
- Understand how substituent chirality dictates helix twist sense.
- Develop methods for controlling foldamer conformation.
Main Methods:
- Nuclear Magnetic Resonance (NMR) spectroscopy
- Circular Dichroism (CD) spectroscopy
- Computational chemistry modeling
Main Results:
- Detailed structure-property relationships of chiral induction were uncovered.
- Identified "ambidextrous" substituents that control twist sense in opposite directions.
- Demonstrated that steric effects, not electronic, govern chiral induction in these systems.
Conclusions:
- Chiral termini effectively control helix handedness in ortho-phenylene foldamers.
- The observed "ambidextrous" behavior provides a generalizable model for chiral induction.
- This work enables precise control over foldamer structure for advanced applications.
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