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Updated: May 25, 2026
08:25
Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)
Published on: January 17, 2020
Conformationally restricted dynamic supramolecular catalysts for substrate-selective epoxidations.
Esmaeil Sheibani1, Kenneth Wärnmark
1Centre for Analysis and Synthesis, Department of Chemistry, Lund University, PO Box 124, SE-221 00 Lund, Sweden.
Organic & Biomolecular Chemistry
|February 4, 2012
Summary
This study presents a second-generation supramolecular catalytic system with enhanced substrate selectivity. Organic synthesis was used to lock the catalyst
Area of Science:
- Supramolecular Chemistry
- Catalysis
- Organic Synthesis
Background:
- First-generation dynamic supramolecular catalytic systems utilize a catalyst and receptor linked by hydrogen bonding.
- Equilibrium analysis of the first-generation system revealed opportunities to enhance catalytic cavity formation.
Purpose of the Study:
- To develop a second-generation substrate-selective dynamic supramolecular catalytic system.
- To increase the amount of the substrate-selective catalytic cavity by locking the cisoid conformation of the catalyst part.
Main Methods:
- Rational design of a second-generation supramolecular catalytic system.
- Organic synthesis to 'strap' the catalyst part, locking its conformation.
- Pair-wise competitive epoxidations to assess substrate selectivity.
Main Results:
- The 'strapped' catalyst part successfully locked the cisoid conformation.
- This resulted in increased substrate selectivity compared to the first-generation system.
- Highest selectivity reached 3.4:1 in competitive epoxidations of specific stilbene derivatives.
Conclusions:
- The second-generation supramolecular catalytic system demonstrates improved substrate selectivity through conformational locking.
- This rational design approach offers a pathway to fine-tune catalytic activity and selectivity in supramolecular systems.
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