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Practical radical cyclizations with arylboronic acids and trifluoroborates
Jonathan W Lockner1, Darryl D Dixon, Rune Risgaard
1Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Organic Letters
|September 20, 2011
Summary
This study introduces a practical method for radical cyclizations using organoboronic acids and trifluoroborates in water. These reactions are scalable, air-stable, and utilize mild catalytic conditions for generating complex polycyclic structures.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Radical cyclizations are crucial for synthesizing complex organic molecules.
- Developing mild, efficient, and scalable methods for these transformations remains a key challenge in synthetic chemistry.
Purpose of the Study:
- To develop practical, scalable, and environmentally friendly conditions for radical cyclizations.
- To demonstrate the utility of organoboronic acids and trifluoroborates in these reactions under mild conditions.
Main Methods:
- Utilizing catalytic silver nitrate and stoichiometric potassium persulfate.
- Performing reactions in water under open-air conditions.
- Employing organoboronic acids and trifluoroborates as radical precursors.
Main Results:
- Successful implementation of Pschorr-type cyclizations.
- Demonstration of tandem radical cyclization/trap cascades.
- Generation of diverse polycyclic scaffolds under mild, scalable conditions.
Conclusions:
- The developed method offers a practical and sustainable approach to synthesizing polycyclic compounds.
- The use of water as a solvent and open-air conditions highlight the robustness of the methodology.
- This work expands the toolkit for radical cyclization reactions in organic synthesis.
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