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Updated: Jun 6, 2025
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07:12
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
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Visible-light-induced cascade chromone cyclization/chalcogenation to access 3-chalcogenyl-chromones using elemental
Tao Guo1, Chuanhu Gao1, Zhonghui Li1
1School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou, Henan 450001, P. R. China.
Chemical Communications (Cambridge, England)
|November 26, 2024
Summary
A new visible-light reaction efficiently synthesizes 3-chalcogenyl-chromones using elemental sulfur and selenium. This method offers a mild and versatile approach for creating valuable chromone derivatives at room temperature.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Photochemistry
Background:
- Chromone derivatives are important scaffolds in medicinal chemistry.
- Efficient synthesis of functionalized chromones remains a challenge.
- Visible-light photocatalysis offers a sustainable approach to organic synthesis.
Purpose of the Study:
- To develop a mild and efficient method for synthesizing 3-chalcogenyl-chromones.
- To utilize visible-light-induced cascade reactions for chromone functionalization.
- To employ readily available elemental sulfur and selenium as chalcogen sources.
Main Methods:
- A three-component reaction involving a chromone precursor, elemental sulfur (S8) or selenium (Se), and a visible-light photocatalyst.
- Reaction optimization under mild, room-temperature conditions.
- Characterization of the synthesized 3-chalcogenyl-chromone products using spectroscopic techniques.
Main Results:
- Successful development of a visible-light-induced cascade reaction for chromone cyclization and chalcogenation.
- Efficient synthesis of various 3-chalcogenyl-chromones with good yields.
- Demonstrated wide substrate scope and good functional group tolerance.
Conclusions:
- The developed method provides a convenient and attractive route for synthesizing 3-chalcogenyl-chromones.
- The reaction is mild, efficient, and operates under visible-light irradiation at room temperature.
- This approach expands the synthetic toolbox for accessing functionalized chromone derivatives.
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