Process Study on One-Pot Synthesis of DBX-1 with High Conversion Rate and Intrinsic Safety

Catena-[bis(μ₃-5-Nitrotetrazolate)-dicopper(I)] (DBX-1) is a highly promising new lead-free primary explosive and an ideal substitute for lead azide (LA). However, due to the complex preparation process, low conversion rate of raw materials, and high risk of intermediate products, it is difficult to apply DBX-1 in engineering. This paper proposes a simpler process route that can achieve the conversion from 5-aminotetrazole (5-AT) to DBX-1 in one reaction vessel. Based on the gas generation rate, the process principle of hydronium copper(II)-tris(5-nitrotetrazolate) trihydrate (Intermediate 1) synthesis was analyzed, and the process parameters were optimized. The conversion rate of 5-AT to NT^- was increased to 90%. The synthesis of DBX-1 using copper chloride as a raw material in the presence of CuO and nitrate anions has simplified the process steps. In addition, the comparison of the sensitivity and thermal performance of intermediate 1 and DBX-1 further indicates that this process can greatly improve the intrinsic safety of the process by avoiding the handling of dangerous intermediates.