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Novel high-density oxidizer based on highly nitrated bipyrazole was developed. It is the champion among heteroaromatic CHNO compounds with a density equal to 2.021 g cm−3 at room temperature.

A new family of energetic compounds, nitropyrazoles bearing a trinitromethyl moiety at the nitrogen atom of the heterocycle, was designed. The desirable high-energy dense oxidizers 3,4-dinitro- and 3,5-dinitro-1-(trinitromethyl)pyrazoles were synthesized in good yields by destructive nitration of the corresponding 1-acetonylpyrazoles. All of the prepared compounds were fully characterized by multinuclear NMR and IR spectroscopy, as well as by elemental analysis. Single-crystal X-ray diffraction studies show remarkably high density. Impact sensitivity tests and thermal stability measurements were also performed. All of the pyrazoles possess positive calculated heats of formation and exhibit promising energetic performance that is the range of 1,3,5-trinitroperhydro-1,3,5-triazine and pentaerythritol tetranitrate. The new pyrazoles exhibit positive oxygen balance and are promising candidates for new environmentally benign energetic materials.

The search of the new low-melting high energetic materials, which match the performance of TNAZ and more available, is the barest necessity. The syntheses of several novel zero-hydrogen but nitrogen and oxygen rich high energetic heterocycles, such as bridged nitrofurazans, were undertaken to test the hypothesis that accumulate furazan ring in such molecule could effectively serve in construction of energetically interesting materials. Eight dinitro trifurazans were synthesized and tested. The series of compounds was prepared in three±®ve stages from the 3,4-diaminofurazan (10). Oxy bridge was formed by utilizing hydroxyfurazans as nucleophiles. Azo bridge was prepared by oxidizing coupling of amino groups with KMnO 4 in acid medium. Transformation of azo bridge to azoxy one was accomplished by mixture of (NH 4 ) 2 S 2 O 8 and oleum. The set of trifurazans represents a new class of low-melting high energetic materials which are among the most potent C x H y N z O wexplosives known. The isomeric diazoxyfurazans, (28), (29), and (30), differ dramatically in their properties. Liquid diazoxy compound (28) has density of 1.8 g/cm 3 and is reach a record ®gure for C x H y N z O w -oil known.