Disubstituted azidotetrazoles as energetic compounds

Chemistry. 2009;15(16):4102-10. doi: 10.1002/chem.200900034.

Abstract

Base-catalyzed activation of the C--F bond in the trifluoromethylazo-substituted cyclic and acyclic alkanes provides a route to disubstituted azidotetrazoles. For example, the reaction of 1,2-bis(trifluoromethylazo)ethane with four equivalents of NaN(3) gave the alkyl-bridged bis(5-azido-1H-tetrazol-1-yl)-1,2-dimine, N,N'-bis(5-azido-1H-tetrazol-1-yl)-1,2-diiminoethane, in 75 % yield (see scheme).Disubstituted azidotetrazoles are synthesized by the base-catalyzed activation of the C--F bond in the trifluoromethylazo-substituted cyclic and acyclic alkanes. From the reaction of trans-1,4-bis(trifluoromethylazo)cyclohexane with four equivalents of NaN(3), N,N'-bis(5-azido-1H-tetrazol-1-yl)-1,4-diiminocyclohexane was formed in good yield. While, from the similar reaction using cis/trans-1,2-bis(trifluoromethylazo)cyclohexane, (5-azido-1H-tetrazol-1-yl)-[6-(5-azido-1H-tetrazol-1-ylimino)cyclohexenyl]amine was formed as the principal product. The structure of these new disubstituted azidotetrazoles was determined by crystal structure analysis as well as NMR and IR spectroscopy. In a similar fashion, from three trifluoromethylazo-substituted acyclic alkanes, corresponding alkyl-bridged N,N'-bis(5-azido-1H-tetrazol-1-yl)diiminoalkanes were obtained. For example, from 1,2-bis(trifluoromethylazo)ethane, N,N'-bis(5-azido-1H-tetrazol-1-yl)-1,2-diiminoethane was obtained in 75 % yield. Heats of formation, detonation pressures, detonation velocities, and impact sensitivities are reported for these new disubstituted azidotetrazoles.