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Updated: Jun 12, 2026
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Electro- and Mechanochemical C(sp2)-H Chalcogenations of 4-Hydroxycoumarins/4-Hydroxy-N-methylquinolin-2-one: A Dual
Debojyoti Mukherjee1, Indrajit Karmakar1, Soma Ghosh1
1Laboratory of Natural Products & Organic Synthesis, Department of Chemistry, Visva-Bharati (a Central University), Santiniketan, West Bengal, India.
Abstract:
We report two distinct and complementary synthetic strategies-electrochemical and mechanochemical-for the preparation of diversely functionalized chalcogenated 4-hydroxycoumarins/4-hydroxy-N-methylquinolin-2-one. Each method provides a practical and straightforward route to biologically relevant sulfide- and selenide-functionalized oxygen- and nitrogen-containing heterocycles. The developed protocols offer multiple advantages, including mild and energy-efficient reaction conditions, the elimination of transition-metal catalysts, the use of external heating and additional oxidants, short reaction times, high to excellent yields, a broad substrate scope, gram-scale applicability, operational simplicity, and environmentally friendly execution. Additionally, the synthetic application of the synthesized compounds has been extended.
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