Construction of Bis-Heterocyclic Energetic Compounds via C–N Coupling Reactions

The C–N bonded aromatic compounds have demonstrated potential applications in energetic materials, polymers, agrochemicals, and medicinal chemistry. Developing improved methodologies for the streamlined and economical generation of C–N bonds is highly sought-after. In this study, an efficient strategy was developed to construct C–N bonded bis-heterocyclic compounds. A total of 26 substrates with different functional groups substituted azoles were selected to react with 1,3,4-trinitropyrazole. The results demonstrate that the C–N coupling reaction is predominantly influenced by the pKa of the substrates. The relationships between the substrates and C–N coupling products were meticulously investigated and determined. Among those products, compounds 3a–3d exhibit high thermostability and comparable detonation properties to that of RDX, indicating significant potential for use as secondary explosives. The method presented in this work may also serve as a powerful toolkit to design and synthesize C–N bonded bis-heterocyclic compounds in the domains of medicinal chemistry and organic materials.