Combination of gem-dinitromethyl functionality and a 5-amino-1,3,4-oxadiazole framework for zwitterionic energetic materials

Abstract

A series of zwitterionic energetic materials was reported, which exhibited higher densities and better detonation performances than common energetic salts.

Review on the Synthesis and Performance for 1,3,4‐Oxadiazole‐Based Energetic Materials

“…In contrast to 1,2,4-oxadiazole and 1,2,5-oxadiazole, which constitute several energetic materials through a single ring in combination with various explosophoric groups (e. g., amino, nitro, nitramine, and dinitromethyl functionalities), there are a limited number of energetic materials originating from monocyclic 1,3,4-oxadiazole. Zhang et al [49] synthesized two zwitterionic energetic compounds (4 and 6) consisting of a gem-dinitromethyl functional group and an 5-amino-1,3,4-oxadiazole skeleton. Among them, the zwitterionic compound (5-iminio-4,5-dihydro-1,3,4-oxadiazol-2yl)dinitromethanide (4) was synthesized using a four-step synthetic method using commercially available ethyl potassium malonate as the starting material (Scheme 3).…”

“…In the synthesis route shown in Scheme 3, intermediate 3 is mechanically sensitive, while compound 2 exhibits poor stability and is not suitable for long-term storage [49]. Therefore, this method to synthesize zwitterionic compounds and their salts is not suitable owing to the unstable intermediates posing potential risks during the preparation process.…”

3-Methyl-1,2,3-triazolium-1N-dinitromethylylide and the strategy of zwitterionic dinitromethyl groups in energetic materials design

“…11 More recently, it has been shown that zwitterionic energetic materials are able to combine high performance through increased density while also increasing stability through the electrostatic interactions within the same molecule. [12][13][14][15][16][17] N-oxides are widely used in energetic materials due to their ability to increase performance and stability of a compound. 18,19 Introduction of N-oxides oen leads to increased stability of heterocyclic backbones while also helping to increase oxygen balance.…”

“… 11 More recently, it has been shown that zwitterionic energetic materials are able to combine high performance through increased density while also increasing stability through the electrostatic interactions within the same molecule. 12–17 …”

“… 28 Energetic materials that include a dinitromethyl functional group are often high performing and are also an efficient method of creating energetic salts once the acidic proton is removed. 12 Due to these properties, dinitromethyl groups were seen as potential new building blocks for zwitterionic molecules, which could potentially both impart energy while helping increase stability through electrostatic interactions.…”