Research on TNTON/DNTF eutectic characteristics: an exploration of low eutectic mixture based melt-cast explosive carriers.

To modify the sensitivity and melting point of the casting of DNTF, a eutectic system of insensitive explosive 3,5,5-trinitro-1,3-oxazinane (TNTON) and DNTF was prepared through a new method. The melting and liquefaction processes of TNTON/DNTF at different ratios were investigated, and a phase diagram was established. The melting and decomposition processes of TNTON, DNTF, and TNTON/DNTF eutectic at different heating rates were compared, while the sensitivity tests were conducted to study the desensitizing effect of TNTON on DNTF.

Performance enhancement strategy for tetrazoles based on nitrogen-boron bonds.

Based on N-B bonds, a novel strategy was developed for improving the energetic performance of tetrazoles. By employing the amino neighboring group participation, the azolyl borane compound 7 was selectively constructed, which exhibited excellent stability in water and air. This strategy solved the acidity problem of tetrazole as well as increasing the heat of detonation and combustion by 25% and 36%, respectively.

Methyl nitrate energetic compounds based on bicyclic scaffolds of furazan-isofurazan (isoxazole): syntheses, crystal structures and detonation performances.

Two energetic bicyclic scaffolds (furazan-isoxazole and furazan-1,3,4-oxadiazole) were constructed different cyclization reactions. Based on the energetic bicyclic scaffolds, the energetic compounds, 3-(4-nitraminofurazan-3-ly)-isoxazole-5-methylnitrate 1c and 5-(4-nitraminofurazan-3-ly)-1,3,4-oxadiazole-2-methylnitrate 2c, were designed and synthesized in good yields. Because of the acidity of nitramine, the corresponding energetic ionic salts, ammonium 3-(4-nitraminofurazan-3-ly)isoxazole-5-methylnitrate 1d and ammonium 5-(4-nitraminofurazan-3-ly)-1,3,4-oxadiazole-2-methylnitrate 2e, were also obtained and well characterized, their structures were further determined by X-ray single crystal diffraction.

Synthesis of Energetic 7-Nitro-3,5-dihydro-4-pyrazolo[4,3-][1,2,3]triazin-4-one Based on a Novel Hofmann-Type Rearrangement.

Rearrangement reactions are efficient strategies in organic synthesis and contribute enormously to the development of energetic materials. Here, we report on the preparation of a fused energetic structure of 7-nitro-3,5-dihydro-4-pyrazolo[4,3-][1,2,3]triazin-4-one (NPTO) based on a novel Hofmann-type rearrangement. The 1,2,3-triazine unit was introduced into the fused bicyclic skeleton from a pyrazole unit for the first time.

5-Nitrotetrazol and 1,2,4-Oxadiazole Methylene-Bridged Energetic Compounds: Synthesis, Crystal Structures and Performances.

A new structural type for melt cast materials was designed by linking nitrotetrazole ring with 1,2,4-oxadiazole through a N-CH-C bridge for the first time. Three N-CH-C linkage bridged energetic compounds, including 3-((5-nitro-2H-tetrazol-2-yl) methyl)-1,2,4-oxadiazole (NTOM), 3-((5-nitro-2H-tetrazol-2-yl)methyl)-5-(trifluoromethyl)-1,2,4 -oxadiazole (NTOF) and 3-((5-nitro-2H-tetrazol-2-yl)methyl)-5-amine-1,2,4-oxadiazole (NTOA), were designed and synthesized through a two-step reaction by using 2-(5-nitro-2H-tetrazole -2-yl)acetonitrile as the starting material. The synthesized compounds were fully characterized by NMR (H, C), IR spectroscopy and elemental analysis.

Synthesis and properties of azamonocyclic energetic materials with geminal explosophores.

Diversity-oriented synthesis of energetic pyrimidine structures with geminal explosophoric groups of geminal dinitro and azido-nitro groups via a novel reductive cleavage and oxidative coupling strategy is reported. Fluorine has also been introduced for the first time based on the nucleophilic coupling process. The obtained energetic pyrimidines are investigated via X-ray diffraction and theoretical techniques of electrostatic potential and proton affinity calculations.

Synthetic and thermal studies of four insensitive energetic materials based on oxidation of the melamine structure.

Oxidation of nitrogen-rich aromatic heterocycles has a significant impact on the development of energetic materials. 2,4,6-Triamino-1,3,5-triazine-1,3-dioxide (MDO) is a promising insensitive energetic backbone obtained from melamine under strong oxidation conditions with impressive thermal behaviors and detonation performances. In this paper, MDO was prepared with improved yields of 85% and its thermal behavior, non-isothermal decomposition kinetics and gas products were investigated in detail.

A comparative study of the structures, thermal stabilities and energetic performances of two energetic regioisomers: 3(4)-(4-aminofurazan-3-yl)-4(3)-(4-nitrofurazan-3-yl)furoxan.

Although energetic regioisomers have attracted intensive attention due to their interesting structure-property correlation, their effective synthesis and accurate identification has remained very difficult. In this paper, we synthesized two energetic regioisomers, namely 3-(4-aminofurazan-3-yl)-4-(4-nitrofurazan-3-yl)furoxan (ANFF-34) and 4-(4-aminofurazan-3-yl)-3-(4-nitrofurazan-3-yl)furoxan (ANFF-43), a controllable strategy with improved yields of 32% and 38%, respectively. The structures of ANFF-34 and ANFF-43 were unambiguously identified using comparative studies of N NMR and single-crystal X-ray diffraction.

3,4-Bis(3-tetrazolylfuroxan-4-yl)furoxan: A Linear C-C Bonded Pentaheterocyclic Energetic Material with High Heat of Formation and Superior Performance.

The design and preparation of new nitrogen-rich heterocyclic compounds are of considerable significance for the development of high-performing energetic materials. By combining nitrogen-rich tetrazole and oxygen-rich furoxan, a linear C-C bonded pentaheterocyclic energetic compound, 3,4-bis(3-tetrazolylfuroxan-4-yl) furoxan (BTTFO), was synthesized using a facile and straightforward method. Comprehensive X-ray analysis reveals the key role of hydrogen bonds, π-π interactions, and short contacts in the formation of dense packing of BTTFO and explains why a long chain-shaped molecule has a high density.

A promising insensitive energetic material based on a fluorodinitromethyl explosophore group and 1,2,3,4-tetrahydro-1,3,5-triazine: synthesis, crystal structure and performance.

The introduction of fluorodinitromethyl energetic groups is an efficient strategy to improve the performances of energetic materials. In this paper, an insensitive energetic compound 6-(fluorodinitromethyl)-3-nitro-1,2,3,4-tetrahydro-1,3,5-triazine (FMTNT) was designed and synthesized based on the modification of 1,3,5-triazine backbone the nitration-rearrangement, reduction and fluorination sequence. The single crystal of FMTNT was firstly obtained and determined, meanwhile, this novel structure was also fully characterized by the methods of IR, H NMR, C NMR, F NMR and elemental analysis.

A Family of Energetic Materials Based on 1,2,4-Oxadiazole and 1,2,5-Oxadiazole Backbones With Low Insensitivity and Good Detonation Performance.

Design and synthesis of new compounds with both high detonation performances and good safety properties have always been a formidable task in the field of energetic materials. By introducing -ONO and -NHNO moieties into 1,2,4-oxadiazole- and 1,2,5-oxadiazole-based backbones, a new family of energetic materials, including ammonium 3-nitramino-4-(5-hydroxymethyl-1,2,4-oxadiazol-3-yl)-furazan (4), 3,3'-bis[5-nitroxymethyl-1,2,4-oxadiazol-3-yl]-4,4'-azofuroxan (6), [3-(4-nitroamino-1,2,5-oxadiazol-3-yl)-1,2,4-oxadiazol-5-yl]-methylene nitrate (8), and its energetic ionic salts (10-12), were synthesized and fully characterized. The energetic and physical properties of the materials were investigated through theoretical calculations and experimental determination.

Effect of Fluoro Substituents on Polynitroarylenes: Design, Synthesis and Theoretical Studies of Fluorinated Nitrotoluenes.

The replacement of traditional polynitroarylenes by their fluorinated derivatives has attracted great attention due to the improvements on detonation performance caused by the fluorine effect. A straightforward synthesis of three novel fluorinated nitrotoluenes with different degrees of nitration was achieved under selected high temperatures. The fluorine exerted remarkable influence on the nitration process through the electron-withdrawing effect and a mechanism of the transformation was proposed according to the experimental results.

Synthesis, Characterization and Performance of Promising Energetic Materials Based on 1,3-Oxazinane.

1,3-oxazinane is an ideal framework for advanced energetic materials because of its compact skeleton and the presence of several modifiable sites. However, investigations on characterization and performance of 1,3-oxazinane energetic compounds are extremely limited. Two heterocyclic 1,3-oxazinane molecules were synthesized under different Mannich condensation processes and further reacted to form nitro- and azide-substituted energetic compounds 3,5,5-trinitro-1,3-oxazinane (TNTON) and 5-azido-3,5-dinitro-1,3-oxazinane (ADTON), in good yields.

The Ingenious Synthesis of a Nitro-Free Insensitive High-Energy Material Featuring Face-to-Face and Edge-to-Face π-Interactions.

Density, detonation property, and sensitivity may be the most valued features when evaluating an energetic material. By reasoning structure-property relationships, a nitro-free planar energetic material with high nitrogen and oxygen content, 7-hydroxy-difurazano[3,4-:3',4'-]furoxano[3″,4″-]azepine (), was synthesized using a unique and facile approach. The structure was fully characterized by IR and NMR spectra, elemental analysis, differential scanning calorimetry (DSC), and single-crystal X-ray diffraction.

New Strategy for Enhancing Energetic Properties by Regulating Trifuroxan Configuration: 3,4-Bis(3-nitrofuroxan-4-yl)furoxan.

It is of current development to construct high-performance energetic compounds by aggregation of energetic groups with dense arrangement. In this study, a hydrogen-free high-density energetic 3,4-bis(3-nitrofuroxan-4-yl)furoxan (BNTFO-I) was designed and synthesized in a simple, and straightforward manner. Its isomer, 3,4-bis(4-nitrofuroxan-3-yl)furoxan (BNTFO-IV), was also obtained by isomerization.

Experimental and theoretical studies on stability of new stabilizers for N-methyl-P-nitroaniline derivative in CMDB propellants.

Although N-methyl-P-nitroaniline (MNA) was a quite effective stabilizer in composite modified double base (CMDB) propellants, it undergoes crystallization easily from nitroglycerin (NG) during storage. In order to improve its solubility in nitroglycerin (NG) and the stability in propellants, several new stabilizers including N-ethyl-p-nitroaniline (ENA), N-n-propyl-p-nitroaniline (n-PNA), N-i-propyl-p-nitroaniline (i-PNA), N-n-butyl-p-nitroaniline (n-BNA) and N-t-butyl-p-nitroaniline (t-BNA) were designed and synthesized to replace MNA by increasing the carbon chain length. The interaction between NG and different stabilizers was simulation by Materials Studio 5.

High Energy Density Materials Incorporating 4,5-Bis(dinitromethyl)-Furoxanate and 4,5-Bis(dinitromethyl)-3-Oxy-Furoxanate.

3-Oxy-furoxanate is immobilized in a heterometallic energetic metal-organic framework (MOFs). Two furoxan-based MOFs ([Ag K (BDOFO)(BDFO) (H O) ] , [K (BDFO)] ) and a salt ([(BDFO )(NH NH ) (H O)] (BDOFO =4,5-bis(dinitromethyl)-3-oxy-furoxanate, BDFO =4,5-bis(dinitromethyl)-furoxanate) are synthesized and their energetic performance evaluated. This study outlines the systematic investigation of detonation performance of 3-oxy-furoxan and its derivatives.