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Updated: Jul 26, 2025
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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
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Simple Strategy for Benzo[g]chromene Synthesis via a Photochemical Intramolecular Cyclization Reaction
Masashi Yokoya1, Ryo Fujimoto1, Tomoki Kato1
1Department of Pharmaceutical Chemistry, Meiji Pharmaceutical University, 2-522-1, Noshio, Kiyose, Tokyo 204-8588, Japan.
The Journal of Organic Chemistry
|June 22, 2023
Summary
This study introduces a green photochemical method using quinones for synthesizing benzo[g]chromene derivatives. This efficient approach avoids harsh reagents and minimizes waste in organic synthesis.
Area of Science:
- Organic Chemistry
- Photochemistry
- Synthetic Methodology
Background:
- Photochemical reactions offer a sustainable alternative to traditional thermal synthesis.
- Benzo[g]chromene derivatives are valuable heterocyclic compounds with significant biological applications.
Purpose of the Study:
- To develop a facile and eco-friendly photochemical strategy for synthesizing benzo[g]chromene derivatives.
- To explore the utility of photoredox reactions of quinones in C-H bond oxidation for heterocyclic synthesis.
Main Methods:
- Utilized a photoredox reaction involving quinones and C-H bond oxidation.
- Investigated the reaction mechanism using proton nuclear magnetic resonance (1H NMR) spectroscopy.
- Characterized the synthesized benzo[g]chromene derivatives.
Main Results:
- Successfully synthesized benzo[g]chromene derivatives via a photochemical route.
- Identified 1,3-dioxole compounds as key intermediates in the intramolecular cyclization.
- Demonstrated the efficiency of the photoredox strategy for C-H functionalization.
Conclusions:
- The developed photochemical strategy provides a sustainable and efficient method for benzo[g]chromene synthesis.
- The reaction proceeds through a novel mechanism involving photoredox-mediated C-H oxidation and subsequent cyclization.
- The synthesized compounds hold potential for further exploration in medicinal chemistry due to their heterocyclic structure.
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