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1-Amino-1-hydrazino-2,2-dinitroethylene (HFOX) is a potential reactive intermediate for a new class of energetic materials. Now we describe its condensation with various carbonyl compounds in the presence of acidic and basic catalysts. Condensation of HFOX with α-diones and β-diones gives products of much interest. α-Diones undergo cyclization in the presence of base to form six-membered ring products, while β-diones cyclize to five-membered ring products in the presence of acid. One of the exciting reactions is the formation of ammonium (5,6-dimethyl-1,2,4-triazin-3-yl)dinitromethanide salt, 5c, which was isolated by using aqueous ammonia as a nucleophilic base. All new compounds were fully characterized by advanced spectroscopic techniques. The structures of 5, 5c, 5e, 9, 11, and 12a are supported by single crystal X-ray diffraction analysis. Most of the new six membered ring compounds have good thermostabilities (>200 °C), while the fluorinated five membered ring compound, 12b, has the highest density of 2.04 g cm −3 at 25 °C. Heats of formation and detonation properties were calculated by using Gaussian 03 and EXPLO5 software programs. Nearly all new compounds have very good detonation properties, especially, triazine salts, 5e ( D v = 7513 m s −1 ; P = 24.45 G P a), and 5f ( D v = 7948 m s −1 ; P = 26.27 G P a) as well as azide derivative 11 ( D v = 8166 m s −1 ; P = 25.48 G P a), which are superior to TNT ( D v = 6824 m s −1 ; P = 19.40 G P a). These findings provide a new perspective for the synthesis of novel high performing energetic materials.
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Challenging the limits of nitrogen and oxygen content of fused rings
Heat of formation and density have a significant influence on the detonation performance of a compound and are greatly influenced by the nitrogen and oxygen content of a material. Here a family of new materials with high oxygen and nitrogen content was synthesized and characterized. Compound 1 has a nitrogen and oxygen content of 85.3%, with a high density (1.93 g cm −3 ) and high detonation properties (detonation velocity v D = 9503 m s −1 ; detonation pressure P = 41 GPa). The ammonium salt 3 has a nitrogen and oxygen content of 84.9%, a density of 1.86 g cm −3 , a detonation velocity of 9317 m s −1 , and acceptable sensitivities (8 J, 120 N) which are similar to those of HMX . The potassium salt ( 5 ) was characterized by single-crystal X-ray diffraction.
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- Award ID(s):
- 1919565
- PAR ID:
- 10250561
- Date Published:
- Journal Name:
- Journal of Materials Chemistry A
- Volume:
- 8
- Issue:
- 34
- ISSN:
- 2050-7488
- Page Range / eLocation ID:
- 17411 to 17414
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d0ta05933a
