Light-Promoted Dearomative Amination of Nonactivated Arenes via Redox-Neutral Chromium-Nitrenoid Transfer
Hui Xie1, Wei-Long Zeng1, Chu-Qiao Li1
1State Key Laboratory of Soil Pollution Control and Safety, Department of Chemistry, Zhejiang University, Hangzhou310058, China.
Organic Letters
|July 17, 2026
Summary
Researchers developed a novel light-driven chromium-nitrenoid transfer method for dearomatizing nonactivated arenes. This redox-neutral approach enables selective amination of benzene rings, overcoming limitations of previous dearomatization strategies.
Area of Science:
- Organic Chemistry
- Organometallic Chemistry
- Photochemistry
Background:
- Dearomatization reactions are crucial for synthesizing complex organic molecules.
- Traditional dearomatization methods often require activated arenes or harsh conditions.
- Chromium-mediated reactions have shown promise but are limited by specific redox pathways.
Purpose of the Study:
- To develop a novel, light-driven dearomative amination of nonactivated arenes.
- To establish a redox-neutral chromium-nitrenoid transfer mechanism.
- To expand the scope of dearomatization chemistry beyond cationic electrophiles.
Main Methods:
- Utilizing a novel Cr(0) redox-neutral mode with (η6-arene)Cr(CO)3 complexes.
- Employing light irradiation to drive the dearomatization process.
- Investigating dearomative 1,2-hydroamination and 1,2-carboamination reactions.
Main Results:
- Achieved dearomative amination of nonactivated arenes via a redox-neutral Cr-nitrenoid transfer.
- Demonstrated exclusive regio- and stereocontrol in the amination products.
- Showcased broad functional-group tolerance and preferential site-selectivity for arenes over heteroarenes.
Conclusions:
- The developed Cr(0) redox-neutral mode overcomes limitations of traditional Cr(0)/Cr(II) pathways.
- This strategy enables the use of neutral nitrenes as electrophiles in dearomatization for the first time.
- The method offers a versatile and controlled approach for synthesizing functionalized aromatic compounds.
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