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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
N-centered radicals in self-terminating radical cyclizations: experimental and computational studies.
Uta Wille1, Gerold Heuger, Christian Jargstorff
1School of Chemistry/BIO21 Molecular Science and Biotechnology Institute, The University of Melbourne, 30 Flemington Road, Parkville, Victoria 3010, Australia. uwille@unimelb.edu.au
The Journal of Organic Chemistry
|January 17, 2008
Summary
Photochemically generated radicals add to cyclic alkynes, initiating a cascade reaction. This process, a novel self-terminating radical cyclization, efficiently forms bicyclic ketones.
Area of Science:
- Organic Chemistry
- Photochemistry
- Radical Reactions
Background:
- N-centered radicals are reactive intermediates in organic synthesis.
- Cyclic alkynes are versatile building blocks.
- Self-terminating radical cyclizations offer efficient synthetic pathways.
Purpose of the Study:
- To investigate the intermolecular addition of N-centered radicals to cyclic alkynes.
- To explore the resulting radical translocation/cyclization cascade.
- To elucidate the mechanism of bicyclic ketone formation.
Main Methods:
- Photochemical generation of N-centered aminium and amidyl radicals.
- Reaction of radicals with a cyclic alkyne.
- Computational studies to analyze reaction mechanisms.
Main Results:
- Successful intermolecular addition of radicals to cyclic alkyne.
- Initiation of a radical translocation/cyclization cascade.
- Formation of bicyclic ketones via oxidative termination.
Conclusions:
- The study demonstrates a novel synthetic route to bicyclic ketones.
- The reaction represents a modification of self-terminating radical cyclizations.
- Computational analysis provides mechanistic insights into the cascade process.
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