Energetic Derivatives of Nitroguanidine – Synthesis and Properties

Abstract

Nitroguanidine is an individual explosive with an established reputation. It is widely used as a component of gunpowder, rocket propellants, and high explosives. Less known and appreciated, however, is its importance as a substrate in the synthesis of other explosive compounds with even better properties. In this work available information on synthetic methods, structure, and properties of compounds containing the nitroguanidine moiety was collected and analyzed. The most attention was paid to compounds that have already found practical applications and those with unique properties (high-performance, lowsensitivity), as well as compounds that can be further functionalized with energetic functional groups. The results of our literature search indicate that the nitroguanidine moiety should be treated as a particularly interesting building block from the point of view of the synthesis of new highenergy compounds.

Energetic Material Synthesis: Scale-up Using a Novel Modular Microflow Reactor Setup

“…The synthesis of NQ was selected, since it is a commercial product for triple base gun powders 22 and can be used in the synthesis of more advanced energetic materials. 23 The critical step in this synthetic path is the nitration, because it makes the compound an energetic one. However, the isolation of the product proved to be convenient.…”

“…For testing of the reactor setup and to ensure smooth operation, a reaction was chosen that (1) is straightforward, (2) is under conditions (thermal, chemical) exemplary for the synthesis of energetic materials, (3) yields a relatively insensitive product, and (4) is realistic regarding the corrosiveness of the chemicals involved. The synthesis of NQ was selected, since it is a commercial product for triple base gun powders and can be used in the synthesis of more advanced energetic materials . The critical step in this synthetic path is the nitration, because it makes the compound an energetic one.…”

Single-Crystal Diffraction, Raman Spectroscopy, and Density Functional Theory of DTO [N-(1,7-Dinitro-1,2,6,7-tetrahydro-[1,3,5]triazino[1,2-c][1,3,5]oxadiazin-8(4H)-ylidene)nitramide]

“…In contrast, in the molecular approach, a hybrid between a RDX molecule and NGu molecule yields hexahydro-5-nitro-2-(nitroimino)-1,3,5-triazin (NNT, C 3 H 6 N 6 O 4 ) (Scheme 1). NNT presents a ρ = 1750 kg/m 3 , ΔH f 0 (s) = 68.2 kJ/mol, D v = 8.28 km/s, and P CJ = 28.6 GPa with a F s > 350 N. 31,32 Shock impact sensitivity measurements show NNT is more sensitive than NGu but less sensitive than RDX. 33 Thus, NNT offers both high energy content and insensitivity to external stimuli and provides a good framework for designing and synthesizing new energetic and insensitive molecules.…”

“…28,29 Nonetheless, RDX is sensitive to external stimuli [impact sensitivity (I s ) = 6.2−7.5 J, electric spark (ES s ) = 0.2 J, and friction (F s ) = 120 N. 26 In contrast, NGu is less energetic than RDX, as it is presents one nitrimino group [�NNO 2 ; Scheme 1]. NGu exhibits a ρ = 1770 kg/m 3 , ΔH 0 f = −94.7 kJ/ mol, P CJ = 29.0 GPa, and D v = 8.34 m/s], 29 yet it is much more insensitive to external stimuli (ES s > 4 J, I s > 50 J, and F s > 355 N) than RDX 26,30,31 Thus, combining these two compounds in various proportions affords an energetic mixture with an acceptable energy content and sensitivity risk at the macro level. In contrast, in the molecular approach, a hybrid between a RDX molecule and NGu molecule yields hexahydro-5-nitro-2-(nitroimino)-1,3,5-triazin (NNT, C 3 H 6 N 6 O 4 ) (Scheme 1).…”

A novel electrochemical sensor for nitroguanidine determination using a glassy carbon electrode modified with multi-walled carbon nanotubes and polyvinylpyrrolidone

“…31,37–40 In the literature, there are several methods for the determination of NG but no direct electrochemical method has been developed for the purpose, with the exception of an HPLC method using electrochemical detection. 41 Due to the presence of the strongly electron-accepting nitroimine moiety of NG, 42 this compound is expected to show electroactivity if its enrichment on an electrode is made feasible by specific interactions with the electrode constituents. Therefore, this is the first study reporting a direct electrochemical determination of NG.…”