Synthesis and Characterization of Pyrazole‐Triazolone Compound with Exceptional Heat Resistance

Abstract

Efficiently constructing structures with high thermal stability is a key objective in the development of energetic compounds. However, the existing synthesis processes for heat‐resistant energetic materials are frequently hampered by their complexity and low yields. This study presents a significant breakthrough in addressing these challenges. It successfully synthesizes 4‐amino‐5‐(3‐amino‐1H‐pyrazole‐4‐yl)‐2,4‐dihydro‐3H‐1,2,4‐triazol‐3‐one (APTO) using a streamlined two‐step process, achieving an impressive high yield of 87.5 %. The structure was determined through X‐ray single crystal diffraction analysis, revealing a nearly planar intramolecular structure. Hirshfeld surface analysis, weak interaction analysis, and aromaticity analysis were conducted, illustrating a substantial presence of hydrogen bonds and π ‐ π stacking interactions within and between molecules. These interactions contribute significantly to exceptional thermal stability of ATPO. Furthermore, the thermal stability of ATPO was confirmed through DSC analysis, exhibiting a decomposition temperature as high as 365.2°C. This temperature surpasses that of the heat‐resistant explosive HNS (325°C), further validating its excellent thermal stability. The construction of this conjugated structure offers valuable guidance for the future structural design of heat‐resistant energetic materials. It opens up possibilities for the development of novel compounds with improved thermal stability based on similar conjugated architectures.