Indole-ynones as Privileged Substrates for Radical Dearomatizing Spirocyclization Cascades.
Nantachai Inprung1, Hon Eong Ho1, James A Rossi-Ashton1
1Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K.
Organic Letters
|January 5, 2022
Summary
Researchers developed five new synthetic methods for indole-ynones, enabling efficient radical dearomatizing spirocyclization cascade reactions. These methods rapidly generate diverse, functionalized spirocycles, advancing the exploration of radical chemistry.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Radical Reactions
Background:
- Indole-ynones are versatile substrates for cascade reactions.
- Radical dearomatizing spirocyclization offers a pathway to complex molecular architectures.
Purpose of the Study:
- To develop novel synthetic protocols for indole-ynone dearomatization.
- To explore diverse radical generation methods for spirocyclization.
- To generate highly functionalized spirocyclic compounds.
Main Methods:
- Development of five distinct synthetic protocols: cyanomethylation, sulfonylation, trifluoromethylation, stannylation, and borylation.
- Utilized various radical generation techniques, including photoredox catalysis and traditional methods (e.g., AIBN).
- Employed experimental and computational studies to elucidate reaction mechanisms.
Main Results:
- Successfully established five new synthetic routes for indole-ynone transformations.
- Demonstrated the rapid generation of diverse and densely functionalized spirocycles.
- Provided mechanistic insights supporting a radical cascade pathway.
Conclusions:
- Indole-ynones are effective substrates for radical dearomatizing spirocyclization.
- The developed methods offer efficient access to complex spirocyclic scaffolds.
- These findings pave the way for new radical reaction development.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
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