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Published on: November 21, 2017
Red-Light-Driven Giese Reaction Catalyzed by Zinc(II)porphyrin
Yoshitatsu Yotsumoto1, Yusuke Okanishi1, Taiyo Akashi1
1Division of Pharmaceutical Sciences, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan.
The Journal of Organic Chemistry
|June 23, 2026
Summary
A novel red-light-driven Giese reaction enables radical coupling of N-acyloxyphthalimides with alkenes and alkynes. This study highlights selective radical cascade or Giese reactions based on intermediate properties.
Area of Science:
- Organic Chemistry
- Photocatalysis
- Radical Reactions
Background:
- The Giese reaction is a valuable method for carbon-carbon bond formation.
- Developing sustainable and efficient catalytic systems for radical reactions is crucial in organic synthesis.
Purpose of the Study:
- To develop a red-light-driven Giese reaction using a porphyrin photocatalyst.
- To investigate the decarboxylative radical coupling of redox-active N-acyloxyphthalimides with unsaturated compounds.
- To explore the selective reactivity of 3-aryl-substituted N-acyloxyphthalimides.
Main Methods:
- Utilizing [5,15-bis(pentafluorophenyl)-10,20-diphenylporphinato]zinc(II) as a photocatalyst.
- Employing Hantzsch ester as a reductant.
- Conducting red-light irradiation for the reaction.
- Analyzing the electronic and steric properties of radical intermediates to control selectivity.
Main Results:
- Successful red-light-driven Giese reaction achieved via decarboxylative radical coupling.
- Formation of adducts from N-acyloxyphthalimides with electron-deficient alkenes and alkynes.
- Demonstrated selective radical cascade or Giese reactions for 3-aryl-substituted N-acyloxyphthalimides.
Conclusions:
- The developed system provides a sustainable and efficient method for radical additions.
- The study offers insights into controlling selectivity in radical reactions through tuning intermediate properties.
- This work expands the scope of photocatalytic radical reactions in organic synthesis.
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