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Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Functionalized iminium salt systems for catalytic asymmetric epoxidation
P C Page1, G A Rassias, D Barros
1Department of Chemistry, Loughborough University, Loughborough, Leicestershire LE11 3TU, England. p.c.b.page@lboro.ac.uk
The Journal of Organic Chemistry
|October 13, 2001
Summary
New dihydroisoquinolinium salts function as asymmetric epoxidation catalysts. These catalysts achieve enantioselectivities (ee
Area of Science:
- Organic Chemistry
- Catalysis
- Asymmetric Synthesis
Background:
- Asymmetric epoxidation is a crucial transformation in organic synthesis.
- Development of efficient and selective catalysts is an ongoing area of research.
Purpose of the Study:
- To synthesize and evaluate novel dihydroisoquinolinium salts as catalysts for asymmetric epoxidation.
- To investigate the influence of nitrogen substituent functionalities on catalytic performance.
Main Methods:
- Synthesis of a series of dihydroisoquinolinium salts with varying alcohol, ether, and acetal groups.
- Testing the prepared salts as catalysts in asymmetric epoxidation reactions.
- Analysis of enantiomeric excess (ee) of the epoxidized products using chiral chromatography.
Main Results:
- Successful preparation of diverse dihydroisoquinolinium salts.
- Catalytic activity observed in asymmetric epoxidation reactions.
- Enantioselectivities up to approximately 60% were achieved.
Conclusions:
- Dihydroisoquinolinium salts bearing specific nitrogen substituents show promise as asymmetric epoxidation catalysts.
- The structural modifications in the nitrogen substituent can influence the enantioselectivity of the epoxidation process.
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