Abstract: The key step in the preparation of hexanitrohexaazaisowurtzitane (HNIW) is the formation of hydrogenolysis of 2,6,8,12-tetraacetyl-4,10-dibenzyl-2,4,6,8,10,12-hexaazaisowurtzitane (TADBIW) by hydrogenolysis of hydrodebenzylation of 2,4,6,8,10,12-hexabenzyl-2,4,6,8,10,12-hexaazaisowurtzitane (HBIW) with a palladium-based catalyst in the presence of hydrogen. Due to the instability of HBIW, the caged structure of HBIW disintegrated easily in high temperature and acid environment, which was unable to be directly nitrified to synthesize HNIW. Therefore, hydrogenolysis debenzylation of HBIW is basically inevitable. In this process, hydrogenolysis debenzylation and acetylation occur simultaneously, the C-N bond is hydrogenated on the catalyst, and the subsequently formed amine is acetylated with the acetic anhydride. However, the process is complex and has many intermediate products. Current research is mainly focused on the development of new types of catalysts, with little knowledge of the dynamics and mechanisms of the reaction. This study established a new HPLC analysis method, and the concentration changes of raw materials and intermediates could be observed in the same chromatogram. Based on this, the effect of cosolvent and PhBr content on the hydrogenolysis reaction was studied. The reaction temperature was raised to 65℃, the reaction time was shortened to less than 1 h, and the yield reached 78.90%. Based on the optimal reaction conditions, the kinetics of the hydrogen dehumidification process at the reaction temperature of 18~45℃ were studied, and the concentration change law of each intermediate and reaction product in the reaction process was obtained through quantitative analysis and was inferred that the later stage was mainly acetylating. The process of converting raw materials into intermediates follows first-order reaction kinetics. The intermediate produces the product, following zero-order reaction kinetics; the apparent activation energies were Ea1=62.43 kJ/mol and Ea2=52.80 kJ/mol, respectively. The predigital factors were A1=6.81×109 min-1, A2=5.91×108 mmoL/min; The linear correlation coefficients were R12=0.99181, R22=0.98897. The continuous synthesis method was further developed, and the yield of TADBIW could reach 95.89% at a reaction temperature of 70℃ and a residence time of 4 min.

Key words: hydrogenolytic debenzylation, reaction mechanism, continuous flow, hexabenzylhexaazaisowurtzitane, tetraacetyldibenzylhexaazaisowurtzitane

摘要： 六苄基六氮杂异伍兹烷(HBIW)配合钯基催化剂在氢气环境中进行氢解脱苄反应，生成四乙酰基二苄基六氮杂异伍兹烷(TADBIW)，是制备六硝基六氮杂异伍兹烷(HNIW)的关键步骤。本研究新建立一种HPLC分析方法，同时检测到原料与中间体的浓度变化情况。并以此为基础，研究了助溶剂和PhBr含量对氢解反应的影响，不仅将初始温度提升至65℃，同时反应时间也缩短至1 h以内，收率也达到78.90%。在优选反应条件基础上，对18~45℃反应温度下的氢解脱苄过程进行动力学研究，通过定量分析，得到反应过程中各中间体和反应产物的浓度变化规律，并以此推断后期主要是乙酰化反应。氢解脱苄中原料转化中间体，遵循一级反应动力学；中间体生成产品，遵循零级反应动力学，表观活化能分别为Ea1=62.43 kJ/mol, Ea2=52.80 kJ/mol；指前因子分别为A1=6.81×109 min-1, A2=5.91×108 mmoL/min；线性相关系数R12=0.99181, R22=0.98897。并进一步开发了连续合成方法，在反应温度70℃，停留时间4 min以内，TADBIW可达到95.89%的收率。

关键词: 氢解脱苄, 反应机理, 连续流, 六苄基六氮杂异伍兹烷, 四乙酰基二苄基六氮杂异伍兹烷