![Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F51444.jpg&w=3840&q=50)
Visible-light-driven palladium-catalyzed Dowd-Beckwith ring expansion/C-C bond formation cascade
Li Chen1, Li-Na Guo1, Shuai Liu1
1School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Xi'an Jiaotong University Xi'an Shaanxi 710049 China.
Chemical Science
|June 24, 2021
Summary
This study introduces a novel palladium-catalyzed reaction for synthesizing cyclic ketones. The method efficiently creates complex molecules with quaternary carbon centers using visible light and various alkenes.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- The Dowd-Beckwith reaction is a known method for ring expansion.
- Developing efficient methods for constructing cyclic ketones with quaternary centers is important in organic synthesis.
Purpose of the Study:
- To develop a visible-light-induced palladium-catalyzed cascade reaction.
- To synthesize β-alkenylated cyclic ketones with quaternary carbon centers.
Main Methods:
- Visible-light irradiation.
- Palladium catalysis.
- Dowd-Beckwith ring expansion combined with C-C bond formation.
Main Results:
- Successfully synthesized six- to nine-membered β-alkenylated cyclic ketones.
- Achieved formation of quaternary carbon centers.
- Demonstrated compatibility with styrenes, silyl enol ethers, and enamides.
- Obtained products in moderate to good yields under mild conditions.
Conclusions:
- The developed method provides an efficient route to complex cyclic ketones.
- The reaction is versatile, accommodating various electron-rich alkenes.
- Visible-light catalysis offers a sustainable approach for this transformation.
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