Facile synthesis of 4-amino-3,5-dinitropyrazolated energetic derivatives via 4-bromopyrazole and their performances

Abstract

The development of practical synthetic strategies towards novel energetic materials fulfilling various civilian and military purposes is a desirable but challenging task. 4-Amino-3,5-dinitropyrazole, an insensitive energetic material, has great potential as an effective building block for the construction of promising primary and secondary explosives. Herein, a facile strategy for the synthesis of 4-amino-3,5-dinitropyrazolate-based energetic derivatives is achieved using 4-bromopyrazole as starting material. The resulted energetic compounds 1–9 were well characterized through IR spectroscopy, multinuclear NMR spectroscopy, and differential scanning calorimetry. The results show that the extension of the three-dimensional caged packing structure related to the hydrogen bonding interactions and self-assembling of potassium ions with 3,5-dinitro-4-aminopyrazolate ligands, could reinforce its thermal stability with a decomposition temperature of 307.0 °C. Thermal stability, sensitivities, as well as detonation performances were studied by the experimental tests and calculated methods. Overall, this work offers a significant improvement and can lead to the broad practical use of 4-amino-3,5-dinitropyrazole as a building block for promising energetic materials.

Keywords

• Energetic compounds
• 4-bromopyrazole
• Diazonium zwitterions
• Facile synthesis
• Detonation performance