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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
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Effector enhanced enantioselective hydroformylation
Shao-Tao Bai1, Alexander M Kluwer2, Joost N H Reek3
1Homogeneous, Supramolecular and Bio-inspired Catalysis, Van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam (UvA), Science Park 904, 1098 XH Amsterdam, The Netherlands. j.n.h.reek@uva.nl.
Chemical Communications (Cambridge, England)
|November 9, 2019
Summary
Chiral rhodium complexes with integrated receptors enhance enantioselective hydroformylation when bound to effectors. This supramolecular approach significantly boosts selectivity in rhodium-catalyzed reactions.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Supramolecular Chemistry
Background:
- Rhodium-DIMPhos complexes are key catalysts in hydroformylation.
- Achieving high enantioselectivity in hydroformylation remains a challenge.
- Supramolecular control offers a potential strategy for catalyst enhancement.
Purpose of the Study:
- To develop rhodium DIMPhos complexes with integrated receptors for carboxylate-containing effectors.
- To investigate the application of these supramolecular complexes in rhodium-catalyzed hydroformylation.
- To evaluate the impact of effector binding on regio- and enantioselectivity.
Main Methods:
- Synthesis of rhodium DIMPhos complexes featuring an integrated DIM-receptor.
- Binding of achiral and chiral carboxylate-containing effectors to the supramolecular complex.
- Application of the modified catalysts in the hydroformylation of vinyl acetate.
- Analysis of reaction products for regio- and enantioselectivity (ee, b/l ratios).
Main Results:
- The binding of achiral or chiral effectors significantly enhanced enantioselectivity compared to non-complexed catalysts.
- A supramolecular complex ([Rh]/[1S⊂L3]) achieved high regio- and enantioselectivity (72% ee, b/l >99) in vinyl acetate hydroformylation.
- Non-chiral [Rh(DIMPhos)] catalysts with chiral effectors did not induce enantioselectivity.
Conclusions:
- Integrated DIM-receptors in rhodium DIMPhos complexes enable supramolecular control over catalysis.
- Effector binding is crucial for enhancing enantioselectivity in chiral rhodium-metal complexes.
- This supramolecular strategy provides a powerful tool for optimizing regio- and enantioselective hydroformylation.
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