Promising Energetic Asymmetric Bistetrazoles Synthesized via Sequential Cycloaddition Reactions

Herein, we report the successful synthesis of a series of asymmetric bistetrazole-based energetic compounds (<b>4</b>, <b>8</b>, <b>4a</b>-<b>c</b>, and <b>5a</b>-<b>c</b>) starting from 2-(5-amino-4-nitro-1<i>H</i>-pyrazol-3-yl)-2<i>H</i>-5-cyanotetrazol (<b>3</b>), which was obtained via the reaction of 3,5-diamino-4-nitropyrazole hydrochloride with diazoacetonitrile using a [3 + 2] cycloaddition strategy. All newly synthesized compounds displayed superior detonation performances, particularly 2'-(5-amino-4-nitro-1<i>H</i>-pyrazol-4-yl)-2<i>H</i>,2'<i>H</i>-5,5'-bistetrazole (<b>4</b>), which exhibited exceptional overall performances. These findings underscore the potential of asymmetric bistetrazole derivatives as promising candidates for the development of advanced energetic materials.