Molecular Design and Theoretical Study on Dioxadiazine Energetic Compounds Involving Intramolecular Hydrogen Bonds

The high nitrogen and high oxygen content of energetic dioxadiazine compounds makes them exhibit high detonation performance and good stability, showing possible application in both military and civilian fields. Energetic dioxadiazine compounds with intramolecular hydrogen bonds were designed and optimized, while introducing —NH₂, —NHNO₂, —CH₃, —NO₂, and —OH as modified groups. The bond order, density, enthalpy of formation, stability, detonation performance and inter/intramolecular interactions were analyzed. Results showed that the skeleton of 1,4,2,6-dioxadiazine and 1,4,2,5-dioxadiazine had good stability and symmetrical structure. Analysis of bond length revealed the strong hydrogen bonding between the hydroxyl group and dioxadiazine ring. The introduction of —NH₂ and —OH groups proved beneficial in increasing molecular planarity. Bond order analysis, molecular electrostatic potential (ESP) analysis and detonation parameter calculations showed that B5 and C5 have good stability and detonation properties. Crystal structure prediction suggested that B5 would most likely crystallize in monoclinic (P2₁ space group) while C5 would crystallize in orthorhombic (Pbca space group). Hirshfeld surface analysis indicated strong O···H and N···H interactions for compounds B5 and C5. The above results have a positive promoting effect on obtaining high-energy dioxadiazine compounds with high stability.