From Anion-Centric to Cation-Enabled Energetics: Planar Tetrazine Frameworks with Enhanced Stability

Abstract

Nitrogen-rich heterocycles represent a fertile ground for novel reactions and unusual molecular conversions, which not only advance fundamental heterocyclic chemistry but also enable the design of next-generation energetic materials. Owing to their high energy densities and clean decomposition into environmentally benign nitrogen gas, such frameworks are of growing importance in energy and environmental science. We report a new class of tetrazine-derived cationic and zwitterionic frameworks that enable thermally robust, high-performance energetic salts suitable for advanced propellant and energetic applications. Unlike conventional anioncentric approaches, our design focuses on planar, high-nitrogen tetrazine cations that promote strong π-π stacking, extensive hydrogen bonding, and compact layer-like packing. Our zwitterionic tetrazine highlights how cation engineering and zwitterionic design together expand the scope of tetrazine chemistry toward thermally robust energetic materials. These structural features translate into markedly improved thermal stability This work expands the scope of tetrazine chemistry and highlights the utility of planar high-nitrogen frameworks in the design of stable energetic materials.high-energy explosophores into nitrogen-rich heterocycles has therefore become a major design strategy, as these frameworks enhance energy density while allowing structural diversification through selective functionalization. [6][7][8][9][10] However, this approach often introduces a central drawback: compounds bearing strongly energetic substituents typically suffer from poor thermal stability and increased sensitivity to external stimuli such as impact and friction. [11][12][13][14][15] Balancing energy density with safety thus remains a fundamental challenge in practical energetic-material design.