Amine and nitramine functionalization of imidazole‐triazine and triazole‐triazine skeletons: Exploring for potential multipurpose energetic materials

Abstract

A series of five and six‐membered C‐C bonded energetic materials (2–7) based on a combination of imidazole‐triazine and triazole‐triazine backbones were designed, synthesized, and characterized using NMR, IR, Mass spectrometry, and TGA‐DSC studies. Further, the structure of compound 4 was supported by single‐crystal X‐ray analysis. All the newly synthesized energetic compounds exhibit good density, excellent thermal stability, good detonation performance, and low mechanical sensitivity toward impact and friction. Among all, the nitrate salt 4 exhibits balanced properties, including high density (1.80 g cm−3), excellent thermal stability (254°C), good detonation velocity (8178 m s−1), and low sensitivity towards impact and friction. The facile synthetic feasibility, thermal stability, energetic performance, and insensitivity of all the molecules suggest they can be used as an insensitive secondary explosive in various defense and civilian applications.

Elaborating NH-Bridged Nitrogen-Rich Energetic Materials via Base-Mediated Dimroth Rearrangement: Synthesis, Characterization, and Performance Study

“…Among nitrogen-rich heterocyclic backbones, 1,2,3-triazole and 1,3,5-triazine moieties have garnered attention for their conjugated structures and high heat of formation, making them ideal candidates for designing thermally stable heat-resistant explosives. 23 outlined strategies, incorporating these building blocks with stabilized amino groups into the molecular structures of various energetic materials emerges as a promising approach to designing state-of-the-art energetic compounds. Moreover, employing diverse energy bridges, such as −NH− or − NHNH−, to interconnect two or more energetic rings enhances thermal stability through σ−π hyperconjugation, facilitated by the lone pair of electrons on a nitrogen atom and N-rich heterocyclic backbone.…”

“…(c) The synthesis of energetic salts from their neutral compounds to further enhance insensitivity and thermal stability. − Numerous hydrocarbon-based thermally stable energetic materials have been synthesized, such as trinitrotoluene (TNT, T d = 295 °C), hexanitrostilbene (HNS, T d = 318 °C), and 2,6-bis­(picrylamino)-3,5-dinitro pyridine (PYX, T d = 357 °C). , However, energetic compounds with a hydrocarbon backbone often exhibit a lower heat of formation than nitrogen-rich heterocyclic frameworks, presenting challenges in optimizing detonation performance. Among nitrogen-rich heterocyclic backbones, 1,2,3-triazole and 1,3,5-triazine moieties have garnered attention for their conjugated structures and high heat of formation, making them ideal candidates for designing thermally stable heat-resistant explosives . Considering the outlined strategies, incorporating these building blocks with stabilized amino groups into the molecular structures of various energetic materials emerges as a promising approach to designing state-of-the-art energetic compounds.…”