Synthesis of Energetic Material 4-Nitro-3,5-bis(trinitromethyl)-1H-pyrazole via [4 + 1] Cycloaddition
Wentong Tu1, Tao Yu2, Linyuan Wen2
1School of Materials and Chemical Engineering, Fuyang University of Technology, Fuyang, Anhui 236000, P. R. China.
Organic Letters
|January 23, 2026
Summary
Synthesizing highly nitrated pyrazoles is difficult. This study introduces a new method using nucleophilic substitution and cycloaddition skeletal editing for efficient synthesis of energetic materials.
Area of Science:
- Energetic Materials Science
- Organic Synthesis
- Pyrazole Chemistry
Background:
- Highly nitrated pyrazole derivatives are valuable energetic materials.
- Their synthesis is challenging due to thermal instability and limited reactive sites.
Purpose of the Study:
- To develop a novel and efficient synthetic route for poly-nitrated pyrazoles.
- To explore the application of [4+1] cycloaddition skeletal editing in energetic material synthesis.
Main Methods:
- A five-step synthesis combining nucleophilic substitution and [4+1] cycloaddition skeletal editing.
- A four-step synthesis for the ammonium salt of the target compound.
Main Results:
- Achieved 4-nitro-3,5-bis(trinitromethyl)-1H-pyrazole (compound 1) in 44.1% yield.
- Synthesized the ammonium salt in 56.5% yield.
- Demonstrated the first use of [4+1] cycloaddition skeletal editing for energetic materials.
Conclusions:
- The developed strategy provides an efficient approach for synthesizing poly-nitrated pyrazoles.
- This work expands the synthetic toolbox for energetic materials.
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