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Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
Published on: February 20, 2020
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Towards high-performance Lewis acid organocatalysis
Lars Ratjen1, Manuel van Gemmeren, Fabio Pesciaioli
1Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr (Germany).
Angewandte Chemie (International Ed. in English)
|May 8, 2014
Summary
A novel disulfonimide catalyst, enhanced by Lewis acid organocatalysis and hydrogen-bond assistance, exhibits high activity. This catalyst shows promise for enantioselective transformations, advancing catalytic chemistry.
Area of Science:
- Organic Chemistry
- Catalysis
- Supramolecular Chemistry
Background:
- Lewis acid organocatalysis is a powerful tool in organic synthesis.
- Hydrogen-bond assistance can modulate catalyst activity and selectivity.
- Disulfonimides are versatile scaffolds for catalyst design.
Purpose of the Study:
- To develop a novel disulfonimide catalyst incorporating Lewis acid organocatalysis and internal hydrogen-bond assistance.
- To investigate the enhanced Lewis acidity and catalytic activity of the new catalyst system.
- To demonstrate the utility of the catalyst in enantioselective transformations.
Main Methods:
- Synthesis of a novel disulfonimide catalyst.
- Evaluation of catalytic activity through reaction rate comparisons.
- Theoretical investigations (e.g., DFT calculations) to probe Lewis acidity.
- Application of the catalyst in a model enantioselective reaction.
Main Results:
- A highly active disulfonimide catalyst was successfully developed.
- Theoretical and experimental data confirmed increased Lewis acidity due to combined catalytic strategies.
- The catalyst demonstrated significant potential in achieving enantioselective control in a key transformation.
Conclusions:
- The synergistic combination of Lewis acid organocatalysis and hydrogen-bond assistance leads to highly active disulfonimide catalysts.
- Enhanced Lewis acidity is key to the improved performance of these catalysts.
- The developed catalyst represents a significant advancement for enantioselective synthesis.
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