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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)
Published on: January 17, 2020
Chiral allene-containing phosphines in asymmetric catalysis
Feng Cai1, Xiaotao Pu, Xiangbing Qi
1Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75398-9038, United States.
Journal of the American Chemical Society
|October 7, 2011
Summary
Chiral allenes with basic groups can act as ligands for transition metals. An allene-bisphosphine ligand with Rhodium(I) enables highly enantioselective addition of arylboronic acids to α-keto esters.
Area of Science:
- Organometallic Chemistry
- Asymmetric Catalysis
Background:
- Allenes, specifically chiral 1,2-dienes, are versatile organic molecules.
- The development of novel ligands is crucial for advancing transition metal catalysis.
Purpose of the Study:
- To demonstrate that allenes appended with basic functionality can serve as effective ligands for transition metals.
- To develop and utilize an allene-containing bisphosphine ligand for asymmetric catalysis.
Main Methods:
- Synthesis of an allene-containing bisphosphine ligand.
- Coordination of the ligand to Rhodium(I) complex.
- Application of the resulting catalyst in the asymmetric addition of arylboronic acids to α-keto esters.
- Solution and solid-state structural analysis.
Main Results:
- The allene-bisphosphine ligand successfully coordinated to Rh(I).
- The Rh(I) complex catalyzed the addition of arylboronic acids to α-keto esters with high enantioselectivity.
- Structural analysis confirmed the coordination of one olefin of the allene to the metal center, forming bi- and tridentate ligands.
Conclusions:
- Allenes with basic functionality are viable ligands for transition metals.
- The developed allene-bisphosphine ligand is effective in promoting highly enantioselective conjugate additions.
- The coordination mode of the allene ligand offers opportunities for designing new catalytic systems.
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