An organic thiyl radical catalyst for enantioselective cyclization
Takuya Hashimoto1, Yu Kawamata1, Keiji Maruoka1
1Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan.
Nature Chemistry
|July 24, 2014
Summary
Researchers developed a novel chiral organic radical catalyst for asymmetric synthesis. This thiyl radical catalyst enables highly stereoselective carbon-carbon bond-forming radical cyclizations, advancing enantioselective catalysis.
Area of Science:
- Organic Chemistry
- Asymmetric Catalysis
- Radical Chemistry
Background:
- Chiral organocatalysts typically use acid-base interactions for enantioselective ionic reactions.
- Stereocontrol in radical reactions via organocatalysis is less explored, with limited use of chiral organic radicals directly as catalysts.
Purpose of the Study:
- To design and investigate a novel chiral organic radical catalyst for enantioselective radical reactions.
- To explore the direct use of chiral organic radicals in catalysis for stereocontrol.
Main Methods:
- Design of an organic thiyl radical catalyst featuring a chiral pocket around a thiol precatalyst.
- Application of the catalyst in C-C bond-forming radical cyclization reactions.
Main Results:
- The developed thiyl radical catalyst demonstrated high stereocontrol.
- Highly diastereoselective and enantioselective C-C bond-forming radical cyclizations were achieved.
Conclusions:
- Direct use of chiral organic radicals as catalysts is a viable strategy for enantioselective radical reactions.
- The novel thiyl radical catalyst effectively promotes stereoselective radical cyclizations, expanding the scope of asymmetric organocatalysis.
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