Enantioselective C-H bond functionalization under Co(III)-catalysis
Bholanath Garai1, Abir Das1, Doppalapudi Vineet Kumar1
1Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh - 208016, India. basker@iitk.ac.in.
Chemical Communications (Cambridge, England)
|March 5, 2024
Summary
Sustainable enantioselective C-H functionalization is advanced using earth-abundant cobalt catalysts. High-valent cobalt systems offer promising alternatives to precious metals for asymmetric catalysis.
Area of Science:
- Organic Chemistry
- Catalysis
- Sustainable Chemistry
Background:
- Precious 4d and 5d transition metal catalysts for enantioselective C-H functionalization face sustainability challenges due to resource depletion.
- Earth-abundant and low-toxicity 3d transition metals are emerging as sustainable alternatives.
- High-valent cobalt, particularly, shows unique reactivity for catalytic C-H functionalization.
Purpose of the Study:
- To review recent advancements in high-valent cobalt-catalyzed enantioselective C-H functionalization.
- To highlight the potential of cobalt as a sustainable catalyst in asymmetric synthesis.
- To encourage further research and discoveries in this evolving field.
Main Methods:
- Focus on high-valent cobalt catalysis for C-H functionalization.
- Exploration of cobalt catalysts with various chiral ligands and directing groups.
- Review of developments up to October 2023.
Main Results:
- Development of chiral Cp#Co(III)-catalysts.
- Utilization of chiral carboxylic acids with achiral Cp*Co(III)-catalysts.
- Investigation of cobalt/salox and cobalt/chiral phosphoric acid hybrid systems.
- Successful application in asymmetric catalysis with mono and bidentate directing groups.
Conclusions:
- High-valent cobalt catalysts are effective for enantioselective C-H functionalization.
- Cobalt offers a sustainable and viable alternative to precious metals in asymmetric catalysis.
- The field shows significant promise for future discoveries in synthetic chemistry.
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