Synthesis and Investigation of Advanced Energetic Materials Based on Bispyrazolylmethanes

Dennis Fischer; Jennifer L Gottfried; Thomas M Klapötke; Konstantin Karaghiosoff; Jörg Stierstorfer; Tomasz G Witkowski

doi:10.1002/anie.201609267

Synthesis and Investigation of Advanced Energetic Materials Based on Bispyrazolylmethanes

Angew Chem Int Ed Engl. 2016 Dec 23;55(52):16132-16135. doi: 10.1002/anie.201609267. Epub 2016 Nov 25.

Authors

Dennis Fischer¹, Jennifer L Gottfried², Thomas M Klapötke¹, Konstantin Karaghiosoff¹, Jörg Stierstorfer¹, Tomasz G Witkowski¹

Affiliations

¹ Department of Chemistry, University of Munich (LMU), Butenandtstrasse 5-13 (D), 81377, München, Germany.
² RDRL-WML-B, US Army Research Laboratory, Aberdeen Proving Ground, MD, USA.

PMID: 27885780
DOI: 10.1002/anie.201609267

Abstract

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 °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)=9304 m s^-1 versus V_det (exp)=9910 m s^-1 ) in the range of that of CL-20. Also, the thermal stability (T_dec =205 °C) and sensitivities of 7 are auspicious. The reaction of 6 with in situ 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).

Keywords: X-ray diffraction; diazo compounds; energetic materials; nitrogen heterocycles; pyrazoles.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.
Research Support, Non-U.S. Gov't