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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)
Published on: January 17, 2020
Catalytic enantioselective oxaziridination.
Lennart Lykke1, Carles Rodríguez-Escrich, Karl Anker Jørgensen
1Center for Catalysis, Department of Chemistry, Aarhus University, Aarhus C, Denmark.
Journal of the American Chemical Society
|August 31, 2011
Summary
This study introduces the first catalytic enantioselective synthesis of oxaziridines. Cinchona alkaloid catalysts enable efficient, highly enantioselective oxidation of imines to valuable chiral oxaziridines.
Area of Science:
- Organic Chemistry
- Asymmetric Synthesis
- Catalysis
Background:
- Oxaziridines are versatile synthetic intermediates.
- Enantioselective synthesis of oxaziridines remains a challenge.
- Organocatalysis offers a sustainable approach to chiral molecule synthesis.
Purpose of the Study:
- To develop the first catalytic enantioselective synthesis of oxaziridines.
- To explore the use of cinchona alkaloid-derived catalysts for imine oxidation.
- To achieve high yields and enantioselectivities in oxaziridine formation.
Main Methods:
- Catalytic enantioselective oxidation of aryl and alkyl aldimines.
- Utilized meta-chloroperoxybenzoic acid (m-CPBA) as the oxidant.
- Employed cinchona alkaloid-derived organocatalysts.
Main Results:
- Achieved the first catalytic enantioselective synthesis of oxaziridines.
- Obtained optically active oxaziridines in good yields.
- Reached high enantioselectivities, up to 94% enantiomeric excess (ee).
Conclusions:
- Cinchona alkaloid-derived catalysts are effective for enantioselective imine oxidation.
- The developed method provides efficient access to chiral oxaziridines.
- Mechanistic studies suggest a stepwise enantioselective oxidation pathway.
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