Recent Progress in the Synthesis of Energetic Compounds Functionalized With Trinitromethyl/Gem-Dinitromethyl Groups

This review provides a concise overview of the trinitromethyl/gem-dinitromethyl functionalized energetic compounds reported over the past decade, focusing on molecular design, synthetic routes, and performance evaluation. The skeletons of these energetic molecules primarily include monocyclic, fused heterocyclic, linked heterocyclic, bridged heterocyclic systems, and ionic salts. As the aspect of synthesis, the predominant strategy for introducing polynitromethyl groups such as trinitromethyl and gem-dinitromethyl remains the nitration of precursor groups, including cyano, ethyl acetate, and acetone moieties on the molecular backbone. However, the implementation of molecular skeleton editing techniques for concurrent construction of cyclic frameworks and incorporation of gem-dinitro energetic groups has experimentally verified that this methodology facilitates more secure and efficient integration of energetic functionalities with molecular skeletons. To address the challenge of balancing safety and energy density in high-energy-density materials, current approaches rely heavily on constructing extensively conjugated molecular frameworks functionalized with trinitromethyl or gem-dinitromethyl. Analysis of reported energetic compounds from the perspectives of molecular design and structure-performance relationships indicates that rational integration of trinitromethyl/gem-dinitromethyl groups with conjugated fused or linked heterocyclic skeletons, along with further expansion of planar conjugated structures, represents an effective strategy for designing novel energetic compounds that simultaneously exhibit high energy content and stability.