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With the increase in the demand for high‐performance composite explosives, the search for advanced energetic melt‐castable compounds has attracted increasing attention in the field of energetic materials. Herein, two new energetic materials with nitromethyl and azidomethyl substituents (1‐(nitromethyl)‐3,4‐dinitro‐1H‐pyrazole (NMDNP) and 1‐(azidomethyl)‐3,4‐dinitro‐1H‐pyrazole (AMDNP) were prepared by the substituent modification of a potential melt‐castable molecule ((3,4‐dinitro‐1H‐pyrazol‐1‐yl) methyl nitrate, MC‐4), respectively. NMDNP exhibited a suitable melting point (90 °C), good thermal stability (Td: 185 °C) and excellent detonation performance (8484 m s−1) and impact sensitivity (25 J), thereby demonstrating promise as an energetic melt‐castable material. Simultaneously, compared with the nitrato‐methyl and azidomethyl substituents, the nitromethyl substituent exhibited greater advantages in regulating performance. [ABSTRACT FROM AUTHOR]

A series of novel fused‐ring pyrazolo[4,3‐c]pyrazole derivatives featuring N‐dinitromethyl and N‐fluorodinitromethyl energetic groups (compounds 3–7) were synthesized using a nine‐step reaction. All these compounds were characterized using multinuclear nuclear magnetic resonance (NMR) spectroscopy, infra‐red (IR) spectroscopy, and elemental analysis. X‐ray diffraction analysis was performed, and the single‐crystal structures of compounds 3, 4, 6, and 7 were obtained. For these newly prepared energetic materials, the thermal stability was determined using differential scanning calorimetry (DSC), while the sensitivities were evaluated using BAM drop hammer and friction test. The calculated heat of formation values and the measured densities were used to determine the detonation parameters, including detonation velocity and pressure, using the EXPLO5 program. Of all the prepared compounds, dipotassium 1,4‐bis(dinitromethyl)‐3,6‐dinitro‐1,4‐dihydropyrazolo[4,3‐c]pyrazole (3) was crystallized as a three‐dimensional energetic metal‐organic framework (MOF) and showed outstanding detonation performances, which even outperformed the traditional primary explosive lead azide. Compound 7 exhibited a high crystal density of 1.939 g cm−3, the high decomposition temperature of 213 °C and desirable impact and friction sensitivities (IS: 12 J; FS: 240 N). These combined properties and performances make these novel fused‐ring energetic compounds suitable candidates for high‐performance energetic materials. [ABSTRACT FROM AUTHOR]

Bis(4-nitraminofurazanyl-3-azoxy)azofurazan ( 1) and ten of its energetic salts were prepared and fully characterized. Computational analysis based on isochemical shielding surface and trigger bond dissociation enthalpy provide a better understanding of the thermal stabilities for nitramine-furazans. These energetic compounds exhibit good densities, high heats of formation, and excellent detonation velocity and pressure. Some representative compounds, for example, 1 ( vD: 9541 m s−1; P: 40.5 GPa), and 4 ( vD: 9256 m s−1; P: 38.0 GPa) exhibit excellent detonation performances, which are comparable with current high explosives such as RDX ( vD: 8724 m s−1; P: 35.2 GPa) and HMX ( vD: 9059 m s−1; P: 39.2 GPa). [ABSTRACT FROM AUTHOR]

Development and molecular engineering of new highly-efficient energetic biocidal materials is a significant challenge and of a great importance. Until now this type of materials included mostly halogen-rich nano-thermites and iodine-rich organic materials. So far, no energetic coordination polymers were reported as precursors for combustion-generated biocidal agents. Here, we demonstrate for the first time the synthesis of uniquely-structured three-dimensional energetic coordination polymer ( ECP3 ) containing Zn metal centers and iodine- and nitrogen-rich bridging ligand ( 2 ). Upon its combustion, ECP3 is capable of generating gaseous reactive iodine species and elemental iodine-coated ZnO particles. ECP3 presents a novel approach for the design of efficient biocidal agents. [ABSTRACT FROM AUTHOR]

The first trinitromethyl-substituted pyrimidine derivative was synthesized by direct nitration of its 2-methylpyrimidine precursor. It has a high density (1.85 g cm−3) and excellent detonation performances (v D = 8600 m s−1, P = 32.8 GPa) that may find useful applications in the field of high energy density materials. [Display omitted] • The first trinitromethyl-substituted pyrimidine derivative was synthesized. • A mild and efficient synthetic method has been developed. • The prepared energetic compound demonstrates its potentials as a high energy density material. The first trinitromethyl-substituted pyrimidine derivative (3) was synthesized by direct nitration of its 2-methylpyrimidine precursor, and its structure was thoroughly characterized by FTIR, NMR, elemental analysis, and single-crystal X-ray diffraction. Compound 3 has a high density (1.85 g cm−3) and excellent detonation performances (v D = 8600 m s−1, P = 32.8 GPa), which highlights its great potential as high-energy density material. Furthermore, this work provides a mild and efficient method for the synthesis of trinitromethyl-substituted pyrimidine derivatives, which might have potential application in the design and synthesis of other trinitromethyl-based heterocyclic compounds. [ABSTRACT FROM AUTHOR]

[Display omitted] • An energetic molecule (NTTD) was obtained by one-step reaction with high yield. • NTTD can act as a heat-resistant and insensitive explosive. • The reaction has many advantages, which are conducive to large-scale preparation. • The derivatives of NTTD were synthesized through simple derivatization reactions. Low cost, high yield, good safety, and simple synthesis process are the problems that must be solved in the engineering preparation of energetic compounds, even beyond the pursuit of high energy level to some extent. In this work, a novel 5,6-fused energetic molecule 2-nitro-[1,2,4]triazolo[1,5- a ][1,3,5] triazine-5,7-diamine (NTTD) was designed and easily obtained. By the introduction of oxidants (HNO 3 and HClO 4) and high-energy groups (–NHNO 2), the derivatives of NTTD were prepared, some of which exhibited good comprehensive properties. Importantly, NTTD features excellent thermostability and low mechanical sensitivities. The whole preparation process has advantages of simple operation, short time, cheap and simple reagents, good repeatability, and high yield, which are conducive to large-scale preparation, indicating that NTTD can be a potential candidate of heat-resistant and insensitive explosives. [ABSTRACT FROM AUTHOR]

• Assembling fuel explosives with oxidants for developing novel energetic materials. • A novel fuel-rich explosive TTDO was designed and synthesized. • TTDOP showed good energy & safety balance and enhanced combustion behavior. Development of advanced energetic materials with promising properties has been intensely-pursued over the past decades. However, traditional strategies for integrating fuel skeleton and oxidizing groups into an organic molecule are very difficult to balance the contradictory relationship between high energy and low sensitivity of energetic materials. In this work, we present a promising approach to develop advanced energetic materials through intermolecular assembly of nitrogen-rich triazine energetic compounds and high-energy oxidants. Under the direction of electrostatic potential and proton affinity calculations, a novel energetic compound 2,4,6-triamino-1,3,5-triazine-1,3-dioxide (TTDO) was rationally designed and synthesized. The easy and effective self-assembly of TTDO with high-energy oxidants afforded a series of novel advanced energetic materials with a good balance between energy and sensitivity. Among these self-assembled energetic materials, TTDOP (a self-assembled energetic material between TTDO and HClO 4) showed a very high density (2.047 g cm−3 at 100 K), detonation properties (9284 m s−1 and 41 GPa) as high as that of HMX and better mechanical sensitivity (13 J and 144 N). Moreover, TTDOP exhibited great promise as a substitute for ammonium perchlorate (AP) in solid propellant formulations due to its high combustion and propulsion performances. This work opens a new avenue to develop intermolecular energetic materials with well balanced energy & sensitivity and versatile functionality. [ABSTRACT FROM AUTHOR]