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Modular Synthesis of Dinitramino-Functionalized Pyrazole-Tetrazole and Its Derivatives: Achieving Superior Detonation
Lingzhun Meng1, Lei Liu1, Zijian Li1
1School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Organic Letters
|July 7, 2026
Summary
Researchers developed a new method to synthesize high-energy-density materials, specifically a pyrazole-tetrazole compound and its salts. These novel energetic materials exhibit enhanced detonation performance and molecular packing density.
Area of Science:
- Materials Science
- Organic Chemistry
- Energetic Materials
Background:
- Developing advanced energetic materials with superior performance and safety is crucial for next-generation applications.
- Existing synthetic strategies often face challenges with steric hindrance in constructing complex heterocyclic backbones.
Purpose of the Study:
- To establish a modular synthetic strategy for novel pyrazole-tetrazole-based energetic materials.
- To investigate the impact of dual nitramino and tetrazole functionalization on material properties.
- To evaluate the detonation performance and sensitivity of synthesized compounds and their salts.
Main Methods:
- Utilized a [3 + 2] cycloaddition reaction to construct the pyrazole-tetrazole core, overcoming steric limitations.
- Employed regioselective nitration for introducing nitramino groups.
- Formed salts with nitrogen-rich bases (hydroxylammonium and hydrazinium) for property tuning.
Main Results:
- Successfully synthesized 3,5-dinitramino-4-(1H-tetrazol-5-yl)-1H-pyrazole and its hydroxylammonium (3a) and hydrazinium (3b) salts.
- Demonstrated significantly enhanced molecular packing density and detonation performance due to synergistic effects.
- Hydroxylammonium salt 3a achieved a detonation velocity of 9335 m·s⁻¹ and pressure of 39.1 GPa; hydrazinium salt 3b reached 9350 m·s⁻¹ and 36.1 GPa, with acceptable sensitivities.
Conclusions:
- The developed modular synthetic strategy provides a versatile platform for designing high-energy-density materials.
- Integration of bridged-ring heterocycles with dual functionalization offers a promising route for next-generation energetic materials.
- The synthesized pyrazole-tetrazole derivatives show potential for advanced energetic applications.
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