Oxygen-Rich 1,2,4-Triazolo [3,4-d]-1,2,4-triazolo[3,4-f]furazano [3,4b]pyrazines as Energetic Materials Aleksei B. Sheremetev,* [a] Vecheslav L. Korolev, [a] AleksandrA.P otemkin, [a, b] Abstract: Ac onvenient one-pot synthesis of 5,10-bis(trinitromethyl)-(5)a nd 5,10-bis(fluorodinitromethyl)furazano[3,4e]di([1,2,4]triazolo)[4,3-a:3',4'-c]pyrazines (6)b ye mploying the reaction of 5,6-dichlorofurazano[3,4-b]pyrazine with 5-(trinitromethyl)-and 5-(1-fluoro-1,1-dinitromethyl)tetrazoles, respectively,w as developed. The protocol was carriedo ut under mild conditions at am oderate temperature and over short reaction times to synthesize the products in excellent yields. For the first time, thesep olynitromethyl-substituted compounds, whichm ay have potential use as explosive and propellant materials,h ave been fully characterized. The burningr ate of compound 5 was shown to be slightly superior to that of 2,4,6,8,10,12-hexanitrohexaazaisowurtzitane (CL-20).[a] Prof. A. B. Sheremetev,V .L.Korolev,A .A.P otemkin, N.

Possible decomposition mechanisms of C nitro and N nitro 1,2,4 triazoles were simu lated. We showed that in addition to the experimentally detected thermolysis products includ ing N 2 , N 2 O, NO, CO 2 , HCN, HNCO, 1,2,4 triazole, 3(5) nitroso 1,2,4 triazole, and 1,2,4 triazolone, some other decompositon products (H 2 O, CO, NO 2 , cyanamide, cyanuric acid, and melamine) can be formed. Using the density functional approach (B3LYP/6 31G* approximation), we assessed the most favorable thermal decomposition pathways of nitro triazoles and studied the relationships between the thermolysis pathways of these substances and their molecular and electronic structures. We found a correlation between the energy gap width (energy difference between the frontier molecular orbitals) and the stabilities of the C nitro 1,2,4 triazole tautomers to thermal decomposition.

Methods for the synthesis of 1,2,4 triazolium 4 nitrimides with nitraminoalkyl , hetaryl methyl, nitro ether, and dinitroalkyl substituents are developed. These compounds are useful models for evaluation of the effect of relative positions of the nitro groups on the properties of substances.

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