A composition of HNE as oxidizer with boron as fuel is being investigated as a new explosive.[1]
Preparation
The first synthesis was described by Wilhelm Will in 1914, using the reaction between the potassium salt of tetranitroethane with nitric acid.[2]
C2(NO2)4K2 + 4 HNO3 → C2(NO2)6 + 2 KNO3 + 2 H2O
A practicable method for industrial use starts with furfural,[3] which first undergoes oxidative ring-opening by bromine to mucobromic acid.[4] In the following step, mucobromic acid is reacted with potassium nitrite at just below room temperature to form the dipotassium salt of 2,3,3-trinitropropanal. The final product is obtained by nitration with nitric acid and sulfuric acid at −60 °C.
Properties
The thermal decomposition of hexanitroethane has been detected at 60 °C upwards in both the solid and solution phases.[5] Above 140 °C, this can occur explosively.[6] The decomposition is first order and is significantly faster in solution than in the solid. For the solid, the following reaction can be formulated:[5]
C2(NO2)6 → 3 NO2 + NO + N2O + 2 CO2
For the decomposition in solution, tetranitroethylene is first formed and can be trapped and detected as a Diels–Alder adduct, for example with anthracene or cyclopentadiene.[7][8]
^ abMarshall, Henry P.; Borgardt, Frank G.; Noble, Paul (1965). "Thermal Decomposition of Hexanitroethane 1a,b". The Journal of Physical Chemistry. 69 (1): 25–29. doi:10.1021/j100885a007. ISSN0022-3654.
^Bretherick, L. (18 March 2017). Bretherick's Handbook of Reactive Chemical hazards. Urben, P. G. (8th ed.). Amsterdam. pp. 240–241. ISBN978-0-08-101059-4. OCLC982005430.{{cite book}}: CS1 maint: location missing publisher (link)
^Griffin, T. Scott; Baum, Kurt (1980). "Tetranitroethylene. In situ formation and Diels-Alder reactions". The Journal of Organic Chemistry. 45 (14): 2880–2883. doi:10.1021/jo01302a024. ISSN0022-3263.
^Tzeng, Dongjaw; Baum, Kurt (1983). "Reactions of hexanitroethane with alcohols". The Journal of Organic Chemistry. 48 (26): 5384–5385. doi:10.1021/jo00174a053. ISSN0022-3263.