Chiral disulfonimides: a versatile template for asymmetric catalysis.
Meghan C Benda1, Stefan France
1School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA. stefan.france@chemistry.gatech.edu.
Organic & Biomolecular Chemistry
|September 17, 2020
Summary
Chiral disulfonimides (DSIs) are powerful organocatalysts that activate diverse substrates like aldehydes and ketones. They enable a wide range of reactions with high stereoselectivity through asymmetric counteranion-directed catalysis.
Area of Science:
- Organic Chemistry
- Asymmetric Catalysis
- Organocatalysis
Background:
- Chiral phosphoric acids (CPAs) are effective organocatalysts but often require basic substrates like imines.
- Development of more acidic organocatalysts is crucial for broader substrate scope.
- Chiral disulfonimides (DSIs) have emerged as a promising class of catalysts with enhanced Brønsted acidity.
Purpose of the Study:
- To review the applications of chiral disulfonimides (DSIs) in organocatalysis.
- To analyze the mechanistic insights of DSI-catalyzed reactions.
- To identify current challenges and future directions in DSI catalysis.
Main Methods:
- Review of literature on DSI-catalyzed reactions.
- Analysis of DSI activation modes (Brønsted, Lewis, bifunctional acid).
- Examination of asymmetric counteranion-directed catalysis (ACDC) in DSI systems.
Main Results:
- DSIs effectively activate a wider range of substrates, including aldehydes and ketones.
- DSI catalysis facilitates diverse reaction types with high stereoselectivity.
- Asymmetric counteranion-directed catalysis (ACDC) plays a key role in inducing stereoselectivity.
Conclusions:
- Chiral disulfonimides represent a versatile and powerful class of organocatalysts.
- DSIs significantly expand the substrate scope compared to traditional CPAs.
- Further research is needed to address mechanistic complexities and expand DSI applications.
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