3-nitro-l,2,4-triazol-5-one

K. -Y. Lee and M. M. Stinecipher, Propellants, Explosives, and Pyrotechnics, 14, 241 (1989). Handrick (Reference 2b) spoke of a salt link or correction of ca 67 kJ mol 1 associated with the formation of a salt from the reaction of an acid and base. From the enthalpy of formation of ethylenediamine from Pedley and of the ethylenediammonium salt of 3-nitro-l,2,4-triazol-5-one from the current reference, and the suggested salt link (x2), the enthalpy of formation of 3-nitro-l,2,4-triazol-5-one is predicted to be —135 kJ mol-1. This is in wonderful agreement with that reported in Reference 103. 

Nitro-l,2,4-triazol-5-one (NTO) (140) is prepared from the nitration of l,2,4-triazol-5-one (139) under a variety of conditions the latter prepared from the condensation of semicarbazide... 

M. D. Coburn and K.-Y. Lee, 3-Nitro-l,2,4-triazol-5-one, a Less Sensitive Explosive , LA-10302-MS, Los Alamos National Laboratory, New Mexico. 

Nitro-l,2,4-triazol-5-one (NTO) [Structure (2.49)] or oxynitrotriazole (ONTA)has been reported as another IHE coupled with better performance [152-157]. Almost all aspects of NTO-synthesis, structural aspects, chemical and explosive properties including thermal behavior have been investigated [158-161]. NTO exists in two polymorphic forms, that is, -form and P-form. It has been established that a-NTO is the stable and dominating form whereas P-NTO is only found in the product on recrystallization of NTO from a methanol or ethanol/methylene chloride mixture [162]. French researchers have recently reported its evaluation as an explosive for warhead filling without a binder and also as a PBX [155]. Further, synthesis of NTO is easy consisting of only two steps (Scheme 2.9) and uses inexpensive starting materials. 

X.Y. (1991) Thermal behaviour of 3-Nitro-l,2,4-triazole-5-one (NTO) and its salts, in Proc. 17th International Pyrotech. Seminar (Combined with the 2nd Beijing Inti. Symp. on Pyrotechnics and Explosives), (eds. O. Yuxiang, F. Changgen and Z. Baoping), Beijing Inst. Tech. Press, Beijing, China, vol. 1, pp. 509-514. 

C NMR spectra of 3-nitro-l,2,4-triazol-5-one and seven of its salts with different amines have been studied. The chemical shifts of C-3 and C-5 are independent of the nature of the cation (Table 3.21) [560], NMR spectra of 1-nitro-1,4-dihydro-1-7/-l,2,4-triazol-5-one, 5-(3-azido-l,2,4-triazol-3-yl)-3-nitro-l,2,4-triazoles [611], l-alkyl-3-nitro-l,2,4-triazol-5-one [612], some 3-nitro-2-methyl-l,2,4-triazolone derivatives [613-615], and their mono- and dinitro energetic salts [616] have been discussed. 

The products of the trimethylsilylation of 3-nitro-l,2,4-triazol-5-one and its methylated analog by hexamethyldisilazane have been supported by H, 13C, 15N and 29Si, NMR spectroscopy [220, 617],... 

Firstly, the nondegenerated tautomers of 3-nitro-l,2,4-triazole-5-one (NTO) radical anions were investigated by ESR method during electrochemical reduction of NTO in aprotic medium at different temperatures. It was shown that observed reversible temperature variations in the ESR spectra of radical anions were caused by tautomerism. Quantum chemical calculations evidence that l,4-/f-tautomer of radical anion is most preferable [881],... 

The vibration spectra of nitrated l,2,4-triazol-5-ones [611, 614, 615] and their energetic salts [616] are discussed. The thermal decomposition mechanism under rapid heating of thin films of 3-nitro-l,2,4-triazol-5-one was studied by pulsed infrared laser and Fourier-transform infrared spectroscopy [1071],... 

All characteristic absorption bands in l-nitro-l,2,4-triazol-5-one are shifted on 30-50 cm-1 in comparison with 3-nitro-l,2,4-triazol-5-one [611]. 

Nitro-l,2,4-triazole-5-one picryl derivatives, amine salts... 

Xue H, Gao H, Twamley B, Shreeve JM (2007) Energetic salts of 3-nitro-l,2,4-triazole-5-one, 5-nitroaminotetrazole, and other nitro-substituted azoles. Chem Mater 19 1731-1739... 

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