A synergistic Rh(I)/organoboron-catalysed site-selective carbohydrate functionalization that involves multiple
V U Bhaskara Rao1,2, Caiming Wang1,2, Daniel P Demarque3
1Abteilung Chemische Biologie, Max Planck Institut für Molekulare Physiologie, Dortmund, Germany.
Nature Chemistry
|December 30, 2022
Summary
This study introduces a novel chiral rhodium(I) and organoboron co-catalysis system for site-selective carbohydrate functionalization. This breakthrough enables efficient synthesis of complex arylnaphthalene glycosides with high stereocontrol.
Area of Science:
- Organic synthesis
- Carbohydrate chemistry
- Catalysis
Background:
- Site-selective functionalization is crucial in organic synthesis.
- Chiral catalysis offers routes to biologically relevant glycosides.
- Robust catalytic systems for complex carbohydrate stereoselectivity remain limited.
Purpose of the Study:
- To develop a novel catalytic system for site-selective functionalization of carbohydrates.
- To enable the synthesis of synthetically challenging arylnaphthalene glycosides.
- To explore the synergistic effects of chiral Rh(I) and organoboron catalysis.
Main Methods:
- A synergistic chiral Rh(I)- and organoboron-catalyzed protocol was developed.
- The method employs chiral Rh(I) catalysis for site-selective carbohydrate functionalization.
- Boronic acid was utilized as a compatible co-catalyst.
Main Results:
- The protocol provides access to synthetically challenging arylnaphthalene glycosides.
- The method demonstrates the utility of boronic acid as a co-catalyst.
- Exquisite stereocontrol, including enantio-, diastereeo-, regio-, and anomeric control, alongside dynamic kinetic resolution, was achieved.
Conclusions:
- A novel synergistic chiral Rh(I)- and organoboron-catalyzed protocol has been established.
- This method overcomes limitations in stereoselectivity for complex carbohydrate functionalization.
- The protocol facilitates the synthesis of biologically relevant glycosides with high precision.
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