N -Functionalisation of 5,5′-bistetrazole providing 2,2′-di(azidomethyl)bistetrazole: a melt-castable metal-free green primary explosive

N -Hydroxymethylation of heterocyclic compounds offers a promising starting procedure to ultimately introduce nitratomethyl- as well as azidomethyl-moieties. Applied to 5,5′-bistetrazole, the resulting 2,2′-di(azidomethyl)bistetrazole (3) and 2,2′-di(nitratomethyl)bistetrazole (4) are high-performing melt-castable energetic materials. Sensitivities were predicted by Hirshfeld analysis and explored in detail by experimental analysis. Because of their increased values towards mechanical stimuli and a short deflagration to detonation transition (DDT), the diazidomethyl derivative especially shows promise as a new melt-castable primary explosive.