Preparation of ε‐HNIW by a One‐Pot Method in Concentrated Nitric Acid from Tetraacetyldiformylhexaazaisowurtzitane

ε‐HNIW was prepared by a one‐pot method in concentrated nitric acid from tetraacetyldiformylhexaazaisowurtzitane (TADFIW). γ‐HNIW was firstly obtained, then γ‐HNIW was directly transformed to ε‐HNIW in the solution in which nitration reaction occurred. The acid number of ε‐HNIW prepared by the method mentioned above is less than 0.2‰, yield of ε‐HNIW is up to 91%, and the purity of ε‐HNIW is up to 99.5%. Because steps of filtration and drying of γ‐HNIW were omitted, the process by which ε‐HNIW was prepared simplified greatly.