Synthesis of Hexanitrohexaazaisowurtzitane from Tetraacetyldiformylhexaazaisowurtzitane

Hexanitrohexaazaisowurtzitane (HNIW) is a polycyclic cage nitramine and the most powerful high energy density compound (HEDC) ever tested. The authors have synthesized HNIW in a yield of 82% in a yield of 72% by the nitrolysis of tetraacetyldiformylhexaazaisowurtzitane (TADFIW) using a complex nitrating agent. Condensation of two benzyl groups at the six - membered ring of tetraacetyldibenzylhexaazaisowurtzitane (TADBIW) into two formyl groups in formic acid gave TADFIW in 72% yield. As described in the literature, TADBIW was prepared from hexabenzyl - hex-aazaisowurtzitane (HBIW) via hydrogenolysis in the presence of Pd(OH)2 catalyst. It was found that the HNIW thus obtained contained a small amount (2% -3%) of incompletely - nitrated product, which was later separated and characterized as pentanitromonoformylhexa - azaisowurtzitane (PNMFIW). The separation of PNMFIW from crude HNIW was carried out using a chromatographic column packed with silica - gel, with acetone as solvent and petroleum benzine (b.p.90 - 120℃ )/ethyl acetate (4:1, V: V) mixture as extracting agent respectively . The analytic results for all the involved compounds are summarized in Table 1. The simple HNIW synthetic method possesses the following advantages: low consumption of catalyst, mild reaction conditions and high yielding.