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 pK _a 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.