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Updated: Jun 29, 2025
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Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
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Interrupted SNAr-Alkylation Dearomatization.
Bilal Altundas1, John-Paul R Marrazzo2, Tore Brinck3
1Department of Chemistry, University of Illinois Urbana-Champagne, 505 South Mathews Avenue Urbana, Champaign, Illinois 61801, United States.
JACS Au
|April 1, 2024
Summary
This study introduces a mild dearomatization method using lithiated nitriles or isocyanides. This efficient synthetic strategy rapidly creates complex carbocycles and heterocycles with new carbon-carbon bonds.
Area of Science:
- Organic Synthesis
- Medicinal Chemistry
Background:
- Dearomatization reactions are crucial for synthesizing carbocycles and heterocycles prevalent in bioactive molecules.
- Traditional dearomatization methods often necessitate harsh reagents due to the stability of aromatic systems.
Purpose of the Study:
- To develop a milder and more efficient dearomatization strategy.
- To enable rapid assembly of complex molecular scaffolds.
Main Methods:
- Utilized lithiated nitriles or isocyanides for SNAr-type addition to aromatic substrates.
- Employed alkylation to trap the intermediate σ-complexes.
- Developed a diastereoselective dearomatization protocol.
Main Results:
- Achieved efficient dearomatization under relatively mild conditions.
- Successfully installed two new carbon-carbon bonds, including a quaternary center.
- Introduced nitrile, isocyanide, and cyclohexadiene functionalities in a single synthetic operation.
Conclusions:
- The described method offers a facile and diastereoselective route to substituted carbocycles and heterocycles.
- This approach simplifies the synthesis of valuable molecular frameworks, potentially accelerating drug discovery.
- The strategy overcomes limitations of traditional dearomatization techniques by employing accessible reagents.
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