Hexanitrobenzene

Hexanitrobenzene, also known as HNB, is a high-density explosive compound with chemical formula C₆N₆O₁₂, obtained by oxidizing the amine group of pentanitroaniline with hydrogen peroxide in sulfuric acid. Its molecular mass is 348.0996 g/mol, its density 1.985 g/cm³, and its heat of formation is 17.48 kJ/mol.

HNB has the undesirable property of being moderately sensitive to light and therefore hard to utilize safely. It is not currently used in any production explosives applications, though it is used as a precursor chemical in one method of production of TATB, another explosive.

HNB was experimentally used as a gas source for explosively pumped gas dynamic laser [2]. In this application HNB and tetranitromethane is preferred to more conventional explosives because the explosion products CO₂ + N₂ are enough simple mixture to simulate gas dynamic processes, and it's quite similar to conventional gas dynamic laser medium. Water and hydrogen as product of many explosive could interfere with vibrational states of CO2 in this type of laser.

Additional recommended knowledge

Essential Laboratory Skills Guide

How to quickly check pipettes?

What is the Correct Way to Check Repeatability in Balances?

Preparation

During World War II a method of synthesis of hexanitrobenzene was suggested in Germany, and the product was supposed to be manufactured on a semi-industrial scale according to the following scheme: C₆H₃(N0₂)₃ -> partial reduction -> C₆H₃(NH0H)₃ -> Nitration -> C₆(NO₂)₃(NH0H)₃ -> oxidation -> C₆(NO₂)₆
straightway nitration of benzene is practically impossible, because -NO2 are deactivating groups for further nitration.

Properties

• Velocity of detonation:
  • 9,340 m/s measured at density 1.965 [3]
• Chapman-Jouget detonation pressure: 43 GPa
• Crystal Density: 2.01

See also

• Octanitrocubane
• Tetryl
• Trinitrotoluene

References

Heats of Formation and Chemical Compositions

The synthesis and characterisation of halogen and nitro phenyl azide derivatives as highly energetic materials., PhD Thesis, Adam, D; 2001

Accurate determination of pair potentials for a C_wH_xN_yO_z system of molecules: A semiempirical method, Thiel et al, 1995

R. L. Atkins, R. A. Hollins, W. S. Wilson (1986). "Synthesis of polynitro compounds. Hexasubstituted benzenes". J. Org. Chem. 51: 3261-3266. doi:10.1021/jo00367a003.

A. T. Nielsen, R. L. Atkins, W. P. Norris (1979). "Oxidation of poly(nitro)anilines to poly(nitro)benzenes. Synthesis of hexanitrobenzene and pentanitrobenzene". J. Org. Chem. 44: 1181-1182. doi:10.1021/jo01321a041.

Z. A. Akopyan, Yu. T. Struchkov, V. G. Dashevskii (1966). "Crystal and molecular structure of hexanitrobenzene". Journal of Structural Chemistry 7: 385-392. doi:10.1007/BF00744430.