Gem‐dinitromethyl‐substituted Energetic Metal–Organic Framework based on 1,2,3‐Triazole from in situ Controllable Synthesis

Abstract

Synthesizing energetic metal-organic frameworks at ambient temperature and pressure has been always a challenge in the research area of energetic materials. In this work, through in situ controllable synthesis, energetic metal-organic framework gem-dinitromethyl-substituted dipotassium 4,5-bis(dinitromethyl)-1,2,3-triazole with a "cage-like" crystal packing was obtained and characterized. Most importantly, for the first time, we found that it could be successfully afforded with a catalytic effect of trifluoroacetic acid. This new compound exhibited its high density (2.04 g cm ) at ambient temperature, superior detonation velocity (8715 m s ) to that of lead azide (5877 m s ) and comparable to that of RDX (8748 m s ). Its detonation products are mainly N (48.1 %), suggesting it is also a green energetic material. The above-mentioned performance indicates its potential applications in detonator devices as lead-free primary explosive.

Synthetic Strategies Toward Nitrogen-Rich Energetic Compounds Via the Reaction Characteristics of Cyanofurazan/Furoxan

“…From a synthetic standpoint, cyano groups in cyanofurazan/furoxan structures enjoy a high degree of transformational diversity and can be further transformed into other heterocyclic five-membered rings such as furoxan, isofurazan, tetrazole, and isoxazole, leading to a series of linear or fused frameworks of nitrogen-rich energetic compounds ( Qu et al, 2016 ; Pagoria et al, 2017 ; Wu et al, 2017 ; Zhai et al, 2019a ; Johnson et al, 2020 ). The cyano groups could also be easily turned to highly powerful explosophoric groups of dinitromethyl, trinitromethyl, and fluorodinitromethyl groups ( Gu et al, 2018 ). Moreover, the additional amino groups in cyanofurazan/furoxan structures provide perfect precursors for the synthesis of azo/azoxy moieties ( Luo et al, 2010 ; Li et al, 2014 ).…”

4,5-Dicyano-1,2,3-Triazole—A Promising Precursor for a New Family of Energetic Compounds and Its Nitrogen-Rich Derivatives: Synthesis and Crystal Structures

“…However, 1,2,3-triazole is a surprisingly stable structure compared to other organic compounds with three contiguous nitrogen atoms [15]. Notably, the 1,2,3-triazole are reported to be more thermally stable and higher heat of formation (240 kJ mol −1 ) than 1,2,4-triazole (182 kJ mol −1 ), owing to the special presence of a N-N-N (N3) structure [16][17][18]. Consequently, the detonation performance and thermal stability of energetic compounds could Molecules 2021, 26, 6735 2 of 13 be enhanced simultaneously by combining 1,2,3-triazole with other heterocycles into one single energetic molecule.…”

Azide-Based High-Energy Metal–Organic Frameworks with Enhanced Thermal Stability

“…HE-MOFs should ideally have high density, elevated heat of detonation, insensitivity to mechanical stress, and high thermal stability. − High heats of detonation can be reached using nitrogen-rich compounds, which have large average bond energies, such as C–N (273 kJ mol –1 ), N–N (160 kJ mol –1 ), NN (418 kJ mol –1 ), and NN (954 kJ mol –1 ) . One promising strategy to design HE-MOFs involves the use of five-membered nitrogen heterocycles as ligands.…”