Derivatives of 3,6-Bis(3-aminofurazan-4-ylamino)-1,2,4,5-tetrazine: Excellent Energetic Properties with Lower Sensitivities.

To find a balance between energy and safety, a series of compounds based on azo, azoxy, 1,4,2,5-dioxadiazene and 3,6-diamino-1,2,4,5-tetrazine bridged bis amino furazan were designed and synthesized. These compounds were analyzed by nitro group charges (Qnitro) and bond dissociation energy (BDE) calculations which are related to sensitivity and stability. Based on the calculated results, derivatives of 3,6-bis(3-aminofurazan-4-ylamino)-1,2,4,5-tetrazine have the largest values for -Qnitro and BDE of all the bis(amino-furazan) compounds. This shows that compounds based on 3,6-bis(3-aminofurazan-4-ylamino)-1,2,4,5-tetrazine have the lowest sensitivities and best stabilities which has been substantiated by experiment. Additionally, their explosive properties remain essentially competitive with compounds based on azo, azoxy and 1,4,2,5-dioxadiazene bridged bis amino furazan. Hirshfeld surface calculations was also studied to better understand the relationship between molecular structure and stability/sensitivity. This work highlights the value of 3,6-diamino-1,2,4,5-tetrazine as a linker to give good balance between safety and energy.