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Dearomative triple elementalization of quinolines driven by visible light
Shiho Ishigaki1, Yuki Nagashima2,3, Daiki Yukimori4
1Department of Chemical Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo, 152-8550, Japan.
Nature Communications
|February 6, 2023
Summary
This study introduces a novel triple elementalization reaction for quinolines, creating complex organoboron and organosilicon compounds. This new method offers a stereoselective route to valuable aliphatic nitrogen heterocycles for drug discovery.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Materials Science
Background:
- Organoboron and organosilicon compounds are vital in synthesis, materials, and pharmaceuticals.
- Accessing complex aliphatic nitrogen heterocycles with multiple boryl/silyl groups from aromatic precursors is challenging.
- Existing dearomative hydroboration/hydrosilylation methods have limitations.
Purpose of the Study:
- To develop a facile and stereoselective method for synthesizing aliphatic nitrogen heterocycles with multiple boryl and silyl groups.
- To explore the dearomative triple elementalization of quinolines.
Main Methods:
- Dearomative triple elementalization (carbo-sila-boration) of quinolines.
- Utilizing organolithium addition followed by photo-boosted silaboration.
- Investigating the reaction mechanism involving silyl radicals.
Main Results:
- Achieved complete chemo-, regio-, and stereoselectivity in the transformation of quinolines.
- Successfully synthesized novel aliphatic nitrogen heterocycles bearing multiple boryl and silyl groups.
- Demonstrated the reaction proceeds via silyl radical intermediates.
Conclusions:
- The developed carbo-sila-boration reaction provides an attractive synthetic platform for complex heterocycles.
- This method offers a significant advancement for drug discovery and materials science.
- Preliminary studies highlight the synthetic utility of the silaboration products.
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