Synthesis and Physicochemical Properties of Energetic 1,2,4,5-Tetrazinyl Derivatives of 5-Nitro-2,4-dihydro-1,2,4-triazol-3-one

摘要

By replacing the pyrazolyl fragment in 3,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)-1,2,4,5-tetrazine with 3-nitro-1,2,4-triazol-5-one (NTO), both mono- and disubstitution products have been synthesized. Further interaction of the obtained compounds with O- and N-nucleophiles led to the preparation of a number of polynitrogen tetrazine derivatives, including 2-6-amino-1,2,4,5-tetrazin-3-yl-5-nitro-2,4-dihydro-3H-1,2,4-triazol-3-one and 5-nitro-2- 6-(1H-tetrazol-5-ylamino)-1,2,4,5-tetrazine-3-yl-2,4-dihydro-3H-1,2,4-triazol-3-one. The reactions of nucleophilic substitution of symmetrically substituted tetrazine were shown to proceed more selectively. The resulting compounds were identified using H-1, (CNMR)-C-13 spectroscopy, FTIR, LC-MS, and elemental analysis, as well as using X-ray diffraction analysis. The thermal stability of the new compounds was evaluated under isothermal and non-isothermal conditions and their energy characteristics were calculated. An unusual drop in stability was found on going from symmetrically substituted tetrazines to asymmetric ones.