Nitrotriazolone

Last updated
Nitrotriazolone [1]
Nitrotriazolone.svg
Names
Preferred IUPAC name
5-nitro-1,2-dihydro-3H-1,2,4-triazol-3-one
Identifiers
3D model (JSmol)
AbbreviationsNTO
ChemSpider
ECHA InfoCard 100.012.050 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 213-254-4
MeSH C420648
PubChem CID
UNII
UN number 0490
  • InChI=1S/C2H2N4O3/c7-2-3-1(4-5-2)6(8)9/h(H2,3,4,5,7)
    Key: QJTIRVUEVSKJTK-UHFFFAOYSA-N
  • C1(=NC(=O)NN1)[N+](=O)[O-]
Properties
C2H2N4O3
Molar mass 130.063 g·mol−1
AppearanceOff white, yellowish beige color to light yellow powder, crystals, or prills
Odor Odourless
Density 1.9 g/cm3 (20 °C)
Melting point 268–271 °C (514–520 °F; 541–544 K)
17,200 mg/L
Solubility Soluble in acetone, ethyl acetate
Slightly soluble in dichloromethane
log P −1.699 (22 °C)
Acidity (pKa)3.76 (20 °C)
Explosive data
Shock sensitivity Very low
Friction sensitivity Very low
Detonation velocity 8,500 m/s
Thermochemistry
124.5 J/K at (47 °C)
−934.4 kJ/mol
Hazards
GHS labelling:
GHS-pictogram-explos.svg GHS-pictogram-flamme.svg GHS-pictogram-exclam.svg GHS-pictogram-silhouette.svg
Danger
H209, H223, H242, H301, H313, H315, H319, H333, H335
P210, P220, P260, P262, P270, P280
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Nitrotriazolone (NTO) is a cyclic semicarbazide-derived high explosive first identified in 1905, but not thoroughly researched until the 1980s. [2] NTO is currently being used by the US Army in specialty insensitive munitions. [3]

Contents

Nitrotriazolone is getting progressively adopted in novel explosive formulations, such as IMX-101, a new, safer alternative to TNT specially devised in 2010 by BAE Systems, where it is combined with 2,4-dinitroanisole (DNAN) and nitroguanidine. As such, NTO is found in the vast majority of IMX formulations. The Picatinny Arsenal has also adopted the implementation of NTO and DNAN in many of their likewise newly developed insensitive explosive mixtures, which share many of the same applications of the IMXs. [4]

Properties

Nitrotriazolone shows keto–enol tautomerism through proton transfer reactions. The keto form shows significantly different stability to heat, friction, and impact. [5]

Nitrotriazolone can form either a mono or dihydrate. [5]

Preparation

NTO was first made in 1905 [6] in a two step process. Semicarbazide hydrochloride is condensed with formic acid to produce 1,2,4-triazol-3-one, which is nitrated with nitric acid to form nitrotriazolone. [7] [5]

Toxicity

In vivo studies showed the nitrotriazolone is absorbed through the skin and gastrointestinal tract. In the kidneys, NTO is broken down into 5-amino-1,2,4-triazol-3-one, which undergoes oxidative denitrification and forms urazoles and nitrites in rats. [8]

References

  1. "Nitrotriazolone". PubChem. National Institutes of Health. Archived from the original on 17 November 2016. Retrieved 16 November 2016.
  2. Jai Prakash Agrawal (20 November 2015). High Energy Materials: Propellants, Explosives and Pyrotechnics. Wiley. pp. 124–. ISBN   978-3-527-80268-5. Archived from the original on 25 January 2021. Retrieved 20 August 2019.
  3. Winstead, Bob (26 October 2011). "Nitrotriazolone: An Environmental Odyssey" (PDF). NDIA Systems Engineering Conference. Archived from the original (PDF) on 13 December 2016. Retrieved 16 November 2016.
  4. Shree Nath Singh (4 August 2013). Biological Remediation of Explosive Residues. Springer Science & Business Media. pp. 285–. ISBN   978-3-319-01083-0. Archived from the original on 25 January 2021. Retrieved 20 August 2019.
  5. 1 2 3 Wei, Rongbin; Fei, Zhongjie; Yoosefian, Mehdi (August 2021). "Water molecules can significantly increase the explosive sensitivity of Nitrotriazolone (NTO) in storage and transport" . Journal of Molecular Liquids. 336 116372. doi:10.1016/j.molliq.2021.116372. S2CID   235575519.
  6. W. Manchot; R. Noll (1905). "Ueber Derivate des Triazols". Justus Liebigs Annalen der Chemie. 343 (1): 1–27. doi:10.1002/JLAC.19053430102. ISSN   0075-4617. Wikidata   Q56659145.
  7. Mukundan, T.; Purandare, G. N.; Nair, J. K.; Pansare, S. M.; Sinha, R. K.; Singh, Haridwar (2002-04-01). "Explosive Nitrotriazolone Formulates". Defence Science Journal. 52 (2): 127–133. doi:10.14429/dsj.52.2157. Archived from the original on 2023-01-29. Retrieved 2022-04-17.
  8. "1,2-dihydro-5-nitro-3H-1,2,4-triazol-3-one". European Chemical Agency. Retrieved 2022-04-16.