Switchable Amination Pathways of Chromones via Iodonium Salt/Amine Modulation.
Shuoshuo Zhang1, Zhifang Yang1, Haofeng Shi1
1Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Faculty of Medicine, Tianjin University, Tianjin 300072, China.
JACS Au
|November 28, 2025
Summary
Chromone-based iodonium salts enable metal-free amination of chromones. A novel pathway involving N-Michael addition and a strained alkyne intermediate allows access to diverse aminated products.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Catalysis
Background:
- Iodonium salts are emerging as metal-free reagents for arene amination.
- Transition-metal catalysis is the conventional method for arene amination.
Purpose of the Study:
- To design and synthesize novel chromone-based iodonium salts (CMISs).
- To demonstrate the efficiency of CMISs in selective chromone amination.
- To elucidate the unique amination mechanism on the chromone scaffold.
Main Methods:
- Synthesis of chromone-based iodonium salts.
- Selective amination reactions using CMISs.
- Mechanistic studies involving N-Michael addition and strained alkyne intermediates.
Main Results:
- CMISs efficiently catalyze selective chromone amination.
- A unique amination pathway involving simultaneous N-Michael addition and formation of a strained alkyne intermediate was identified.
- Modulation of amine basicity and steric hindrance allowed access to three distinct classes of aminated products: (Z)-2-(aminomethylene)-benzofuranones, β-aminochromones, and α-aminochromones.
Conclusions:
- Chromone-based iodonium salts offer a versatile metal-free platform for chromone functionalization.
- The discovered unique mechanistic pathway provides new insights into chromone chemistry.
- This methodology enables controlled synthesis of diverse aminated chromone derivatives.
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