Synthesis and Investigation of Advanced Energetic Materials Based on Bispyrazolylmethanes

Herein we present the preparation and characterization of three new bispyrazolyl-based energetic compounds with great potential as explosive materials. The reaction of sodium 4-amino-3,5-dinitropyrazolate (5) with dimethyl iodide yielded bis(4-amino-3,5-dinitropyrazolyl)methane (6), which is a secondary explosive with high heat resistance (T-dec=310 degrees C). The oxidation of this compound afforded bis(3,4,5-trinitropyrazolyl)methane (7), which is a combined nitrogen- and oxygen-rich secondary explosive with very high theoretical and estimated experimental detonation performance (V-det (theor)=9304ms(-1) versus V-det(exp)=9910ms(-1)) in the range of that of CL-20. Also, the thermal stability (T-dec=205 degrees C) and sensitivities of 7 are auspicious. The reaction of 6 with insitu generated nitrous acid yielded the primary explosive bis(4-diazo-5-nitro-3-oxopyrazolyl)methane (8), which showed superior properties to those of currently used diazodinitrophenol (DDNP).