- Taming of 3,4-Di(nitramino)furazan
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Highly energetic 3,4-di(nitramino)furazan (1, DNAF) was synthesized and confirmed structurally by using single-crystal X-ray diffraction. Its highly sensitive nature can be attributed to the shortage of hydrogen-bonding interactions and an interactive nitro chain in the crystal structure. In order to stabilize this structure, a series of corresponding nitrogen-rich salts (3-10) has been prepared and fully characterized. Among these energetic materials, dihydrazinium 3,4-dinitraminofurazanate (5) exhibits a very promising detonation performance (vD = 9849 m s-1; P = 40.9 GPa) and is one of the most powerful explosives to date. To ensure the practical applications of 5, rather than preparing the salts of 1 through acid-base reactions, an alternative route through the nitration of N-ethoxycarbonyl-protected 3,4-diaminofurazan and aqueous alkaline workup was developed.
- Tang, Yongxing,Zhang, Jiaheng,Mitchell, Lauren A.,Parrish, Damon A.,Shreeve, Jeanne M.
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- 3,3′-Dinitroamino-4,4′-azoxyfurazan and its derivatives: An assembly of diverse N-O building blocks for high-performance energetic materials
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On the basis of a design strategy that results in the assembly of diverse N-O building blocks leading to energetic materials, 3,3′-dinitroamino-4, 4′-azoxyfurazan and its nitrogen-rich salts were obtained and fully characterized via spectral and elemental analyses. Oxone (potassium peroxomonosulfate) is an efficient oxidizing agent for introducing the azoxy N-oxide functionality into the furazan backbone, giving a straightforward and low-cost synthetic route. On the basis of heats of formation calculated with Gaussian 03 and combined with experimentally determined densities, energetic properties (detonation velocity, pressure and specific impulse) were obtained using the EXPLO v6.01 program. These new molecules exhibit high density, moderate to good thermal stability, acceptable impact and friction sensitivities, and excellent detonation properties, which suggest potential applications as energetic materials. Interestingly, 3,3′-dinitroamino-4, 4′-azoxyfurazan (4) has the highest calculated crystal density of 2.02 g cm-3 at 173 K (gas pycnometer measured density is 1.96 g cm -3 at 298 K) for N-oxide energetic compounds yet reported. Another promising compound is the hydroxylammonium salt (6), which has four different kinds of N-O moieties and a detonation performance superior to those of 1,3,5,7-tetranitrotetraazacyclooctane (HMX), and 2,4,6,8,10,12-hexanitro-2,4,6, 8,10,12-hexaazatetracyclododecane (CL-20). Furthermore, computational results, viz., NBO charges and ESP, also support the superior qualities of the newly prepared compounds and the design strategy.
- Zhang, Jiaheng,Shreeve, Jean'Ne M.
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- N-trinitroethyl-substituted azoxyfurazan: High detonation performance energetic materials
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Azoxyfurazan derivatives based on the trinitroethyl functionality were synthesized. These energetic N-trinitroethyl-substituted azoxyfurazans were fully characterized by using 1H and 13C NMR spectroscopy, IR, elemental analysis, differential scanning calorimetry (DSC), thermogravimetric analysis (TG) as well as single crystal X-ray diffraction, and, in the case of N-trinitroethylamino azoxyfurazan 4, with 15N NMR spectroscopy. Furthermore, compound 4 and nitramine 5 have been tested for their responses to impact, friction, and electrostatic discharge. The detonation pressures and velocities of the azoxyfurazan derivatives were calculated, ranging from 35.8 GPa to 41.2 GPa and 8861 m s-1 to 9458 m s-1, respectively. Additionally, compound 5 having an oxygen balance of near zero (+2.5%), exhibits a favorable measured density (1.92 g cm-3) and excellent detonation property (ΔfHm, 962.1 kJ mol-1; P, 41.2 GPa; D, 9458 m s-1). Thus, these compounds could be potential high detonation performance energetic materials.
- Yu, Qiong,Wang, Zhixin,Yang, Hongwei,Wu, Bo,Lin, Qiuhan,Ju, Xuehai,Lu, Chunxu,Cheng, Guangbin
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- Tetracyclic pyrazine-fused furazans as insensitive energetic materials: Syntheses, structures, and properties
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Energetic compounds with fused tetracyclic backbones were synthesized and fully characterized, and their structures were confirmed by single crystal X-ray diffraction. Changes from nonplanar to planar structures led their densities to increase from 1.800
- Sun, Qi,Li, Xin,Lin, Qiuhan,Lu, Ming
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- A study of N-trinitroethyl-substituted aminofurazans: High detonation performance energetic compounds with good oxygen balance
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Two energetic N-trinitroethyl-substituted aminofurazans 11 and 12, as well as nitramine 13 (the N-nitration product of 12) were synthesized. All the compounds were well characterized by NMR spectra, IR spectroscopy, elemental analysis, differential scanning calorimetry (DSC) and thermogravimetric analysis (TG). Their structures were further confirmed by X-ray diffraction studies, which show favorable densities (1.82-1.87 g cm-3). Interestingly, they exhibit good thermal stability (Tdec = 159-230 °C), acceptable oxygen balance (-15.31%-0) and high positive heats of formation (268-1259.5 kJ mol-1). In addition, the performance calculations gave detonation pressures and velocities for the furazan derivatives in the range of 35.4-40.8 GPa and 8900-9486 m s-1, respectively. Furthermore, nitramine 13 (nitrate product of 12), having an oxygen balance of zero, exhibits outstanding detonation properties (ΔfHm, 1259.5 kJ mol-1; D, 9486 m s-1; P, 40.8 GPa), which could be used as a high detonation performance energetic material.
- Yu, Qiong,Wang, Zhixin,Wu, Bo,Yang, Hongwei,Ju, Xuehai,Lu, Chunxu,Cheng, Guangbin
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- A Two-Step Synthesis of Diaminofurazan and Synthesis of N-Monoarylmethyl and N,N'-Diarylmethyl Derivatives
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Diaminofurazan (1) was synthesized from glyoxal (2) by an improved two-step procedure. The N-monoarylmethyl derivatives 4a-e and N,N'-diarylmethyl derivatives 5a-e of 1 were prepared in good yields by reductive alkylation with the corresponding aryl aldehydes.
- Zelenin, Alexander K.,Trudell, Mark L.
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- Tetrazine-furazan ring high-nitrogen energetic compound and synthesis method thereof
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The invention relates to a tetrazine-furazan ring high-nitrogen energetic compound and a synthesis method thereof. The compound is named as 4-amino-N-(3-amino-[1,2,4]triazolo[4,3-b][1,2,4,5-]tetrazine)-1,2,5-oxadiazole-3-amine. The preparation method comprises the following steps: dissolving a compound 2 in DMF, adding sodium hydride under the protection of nitrogen, stirring for 23-26 minutes atthe room temperature, adding a compound 1, reacting for 38-42 minutes, and after the reaction is finished, separating and purifying by column chromatography to obtain a target compound. Furazan ring is used as a latent nitro group and introduced into a tetrazine ring, the energy density and detonation velocity of the compound can be improved, the oxygen balance can be improved, and the synthesis method is simple and safe to operate, short in reaction time, green and environment-friendly.
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Paragraph 0015; 0027-0029
(2020/11/25)
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- Kilogram-grade preparation method of 3,3'-diamino-4,4'-azoxyfurazan
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The invention discloses a kilogram-grade preparation method of 3,3'-diamino-4,4'-azoxyfurazan. The kilogram-grade preparation method is characterized by comprising the following steps: taking glyoxaland the like as raw materials; enabling the raw materials and hydroxylamine hydrochloride to react under an alkaline condition to synthesize an intermediate 3,4-diaminofurazan; then oxidizing the 3,4-diaminofurazan in a sodium bicarbonate solution through potassium bisulfate to obtain a crude product; recrystallizing the crude product to remove impurities, so as to obtain the high-purity 3,3'-diamino-4,4'-azoxyfurazan with the purity of 99.6 percent. The preparation method disclosed by the invention has the advantages of simplicity, short reaction time and stable technology; the prepared 3,3'-diamino-4,4'-azoxyfurazan is especially applicable as initiating explosive for a slapper plate detonator.
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Paragraph 0043; 0047; 0051; 0058; 0066; 0073; 0080; 0087
(2019/02/03)
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- Energetic materials containing fluorine. Design, synthesis and testing of furazan-containing energetic materials bearing a pentafluorosulfanyl group
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The advantageous impact of a pentafluorosulfanyl substituent on the properties of furazan-containing energetic materials was demonstrated by the synthesis and study of the energetic properties of ten new compounds. The thermal stability of these compounds was evaluated by DSC and TGA, whereas densities, heats of formation, pressures of detonation and speeds of detonation were obtained computationally. On the basis of these data, it was concluded that the combination of the SF5 substituent with the furazan ring led to materials of higher density and predicted detonation properties than other known furazans or SF5-containing materials. In addition, the synthetic studies provided insight regarding the electron-withdrawing nature of the furazan ring, in particular its effect on the basicity and nucleophilic reactivity of amino furazans.
- Martinez, Henry,Zheng, Zhaoyun,Dolbier Jr., William R.
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p. 112 - 122,11
(2020/08/20)
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- Process for the manufacture of diaminofurazan
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This invention consists of a method for converting diaminoglyoxime to diaminofurazan that can be carried out efficiently at about atmospheric pressure without the need for high pressure containment apparatus. This invention also consists of a method which comprises converting diaminoglyoxime to diaminofurazan at about atmospheric pressure in the presence of a strong base and/or an organic polar solvent.
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Page/Page column 1-2
(2009/06/27)
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- Microwave mediated fast synthesis of diaminoglyoxime and 3,4-diaminofurazan: Key synthons for the synthesis of high energy density materials
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This paper reports the first microwave-assisted synthesis of diaminoglyoxime (DAG) and diaminofurazan (DAF). The synthesis involved the vicarious nucleophilic substitution of H of glyoxime using hydroxylamine hydrochloride under microwave irradiation for 2 to 3 min to obtain DAG, which on further irradiation in alkali solution for 20 min yielded DAF. Conversion of glyoxime into DAF was also achieved in a one pot sequence in good overall yield using microwave irradiation.
- Kusurkar, Radhika S.,Goswami, Shailesh K.,Talawar, Mahadev B.,Gore, Girish M.,Asthana, Shri N.
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p. 245 - 247
(2007/10/03)
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- Nucleophilic substitution in the furazan series. Reactions of nitrofurazans with ammonia
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The reactions of 3-nitro-4-R-furazans with ammonia were studied. The effect of the substituent R on the specific features of the nucleophilic substitution reaction observed was considered. The nitro group attached to the furazan ring can act as both the l
- Sheremetev,Kulagina,Kryazhevskikh,Melnikova,Aleksandrova
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p. 1533 - 1539
(2007/10/03)
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- Azido-1,2,5-oxadiazoles in reactions with 1,3-dicarbonyl compounds
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The 1,3-dipolar cycloaddition of azido-1,2,5-oxadiazoles (azidofurazans) to dicarbonyl compounds was studied, and a new procedure for the synthesis of 4-R-3-(4-R1-5-R2-1,2,3-triazol-1-yl)-1,2,5-oxadiazoles was proposed.
- Batog, Lyudmila V.,Rozhkov, Vladimir Yu.,Struchkova, Marina I.
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p. 159 - 161
(2007/10/03)
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- Solid-phase versus solution synthesis of asymmetrically disubstituted furazano[3,4-b]pyrazines
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Herein we describe a straightforward solid-phase synthesis directed towards the preparation of families of asymmetrically disubstituted furazano[3,4-b]pyrazines by stepwise displacement of the two chlorine atoms in 5,6-dichlorofurazano[3,4-b]pyrazine by nucleophiles. This synthesis has avoided selectivity problems found in solution chemistry.
- Fernández,García-Ochoa,Huss,Mallo,Bueno,Micheli,Paio,Piga,Zarantonello
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p. 4741 - 4745
(2007/10/03)
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- A Convenient Synthesis of Diaminoglyoxime and Diaminofurazan: Useful Precursors for the Synthesis of High Density Energetic Materials
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The reaction of glyoxime (4) and hydroxylamine hydrochloride in aqueous sodium hydroxide was found to be a safe and inexpensive method for the preparation of multigram quantities of diaminoglyoxime (5).Potassium hydroxide mediated dehydration of 5 furnished diaminofurazan (1) in good yield of exceptional purity.The ready availability of 1 and 5 has facilitated the synthesis of new energetic furazan derivative 8.
- Gunasekaran, Ananthakrishnan,Jayachandran, Thiruvalam,Boyer, Joseph H.,Trudell, Mark L.
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p. 1405 - 1408
(2007/10/03)
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