Enantioselective remote C-H activation directed by a chiral cation
Georgi R Genov1, James L Douthwaite1, Antti S K Lahdenperä1
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.
Science (New York, N.Y.)
|March 14, 2020
Summary
Researchers developed a new method for enantioselective C-H borylation using iridium complexes with anionic bipyridine ligands and chiral cations. This strategy enables asymmetric induction in desymmetrization reactions, offering a novel approach to chiral catalysis.
Area of Science:
- Organometallic Chemistry
- Asymmetric Catalysis
- Synthetic Organic Chemistry
Background:
- Chiral cations are established organocatalysts.
- Enantioselective transition metal catalysis using chiral cations is underexplored.
- Charge-inverted strategies with chiral anions are successful.
Purpose of the Study:
- To develop a novel strategy for enantioselective transition metal catalysis.
- To utilize anionic ligands paired with chiral cations.
- To achieve asymmetric induction in C-H borylation reactions.
Main Methods:
- Anionic modification of a bipyridine ligand.
- Formation of iridium complexes with the anionic ligand.
- Pairing iridium complexes with a chiral quinine-derived cation.
- Application in enantioselective C-H borylation for desymmetrization.
Main Results:
- Successful application of ion-paired iridium complexes for asymmetric induction.
- Demonstrated desymmetrization of geminal diaryl motifs on carbon and phosphorus centers.
- Achieved enantioselective C-H borylation with long-range asymmetric control.
Conclusions:
- The reported strategy offers a new route to enantioselective catalysis using anionic ligands and chiral cations.
- This approach is potentially applicable to a wide range of ligands.
- Highlights the potential of charge-inversion in asymmetric catalysis.
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