This work shows the ability of a readily‐available oxidizer to achieve the selective oxidation of 3,5‐diamino‐1,2,4‐triazole (DAT) to 3‐amino‐5‐nitro‐1,2,4‐triazole (ANTA) in high yields. This strategy reduces the synthesis of this important energetic material and synthon down to a single step. Analysis was conducted on the product and confirmed that the product was indeed ANTA. The yield, safety, and economics of this process are all superior to the current state‐of‐the‐art two‐step multi‐pot procedure.
Very thermostable energetic materials based on a fused-triazole: 3,6-diamino-1 H -[1,2,4]triazolo[4,3- b ][1,2,4]triazole
3,6-Diamino-1 H -[1,2,4]triazolo[4,3- b ][1,2,4]triazole ( 1 ) and its energetic salts ( 2–9 ) were designed and synthesized based on a fused-triazole backbone with two C-amino groups as substituents. Their physicochemical and energetic properties were measured or calculated. Among them, compound 1 exhibits superior thermostability ( T d (onset) : 261 °C), surpassing its analogues 3,7-diamino-7 H -[1,2,4]triazolo[4,3- b ][1,2,4]triazole (DATT, 219 °C) and 3,6,7-triamino-7 H -[1,2,4]triazolo[4,3- b ][1,2,4]triazole (TATOT, 245 °C). The differences in thermal stabilities were further investigated by determining the lowest bond dissociation energies (BDE) where a positive correlation between the stability of the molecules and the lowest BDE values is observed. The results show that 1 with the highest value for the lowest BDE has a superior thermostability in comparison to DATT and TATOT. The energetic salts ( 2–9 ) also exhibit remarkable thermal stabilities as well as low impact and friction sensitivities. The fused-triazole backbone 1 H -[1,2,4]triazolo[4,3- b ][1,2,4]triazole with two C-amino groups as substituents is shown to be a promising building block for construction of very thermally stable energetic materials.
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- Award ID(s):
- 1919565
- NSF-PAR ID:
- 10250551
- Date Published:
- Journal Name:
- New Journal of Chemistry
- Volume:
- 45
- Issue:
- 1
- ISSN:
- 1144-0546
- Page Range / eLocation ID:
- 85 to 91
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d0nj05152g
