Promising Cage-Like Energetic Compounds Based on Dioxaadamantane and Dioxaprotoadamantane Backbones: Facile Synthesis and Energetic Performance

Heteroadamantanes have a wide range of applications, so the efficient construction of their skeletons is an important issue. Herein, two all-bridged carbon-oxygenated cage-like scaffolds 2,6-dioxaadamantane-4,8,9,10-tetraol and 2,7-dioxaprotoadamantane-4,5,9,10-tetraol were constructed through a transannular O-heterocyclization strategy within only two synthetic steps, and six novel energetic materials containing four or five explosophoric groups were synthesized. The densities, oxygen balances (OB_CO), and energetic properties (including detonation velocities and pressures) of all the compounds range from 1.793 to 1.939 g·cm^–3, 8.33 to 13.56%, 8024 to 8701 m·s^–1, and 28.25 to 35.36 GPa, respectively. All the compounds exhibit low sensitivity to both impact (>30 J) and friction (>252 N). It is noteworthy that the symmetry of the scaffolds and the position of substituents affect the physicochemical and energetic properties of the as-prepared compounds obviously. Overall, this study provides a perspective for designing and synthesizing cage-like high energy density materials (HEDMs) and explores the structure-performance relationship.