N_(2)O_(5)硝化四乙酰基六氮杂异伍兹烷的机理研究  

Study on the mechanism of nitration of tetraacetylhexaazaisowurtzitane by N_(2)O_(5)

作　　者：史志健 吕早生 覃远桂 石彬彬 SHI Zhi-jian;LV Zao-sheng;QIN Yuan-gui;SHI Bin-bin(College of Chemistry and Chemical Engineering,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]武汉科技大学化学与化工学院,湖北武汉430081

出　　处：《化学研究与应用》2022年第8期1797-1802,共6页Chemical Research and Application

摘　　要：为了研究N_(2)O_(5)硝化四乙酰基六氮杂异伍兹烷(TAIW)的反应机理,分别在有酸和无酸存在的体系下硝化TAIW,证明在酸催化的条件下,TAIW上的乙酰胺可被硝化成硝胺。应用密度泛函理论(DFT),在B3LYP/6-31G(d, p)水平下对中间产物四乙酰基二硝基六氮杂异伍兹烷(TADN)的乙酰胺硝化机理进行了研究,找到了两种可能反应路径的过渡态,结果表明NO_(2)^(+)在NO_(3)^(-)的协助下可以直接硝化TADN,反应的活化能为134.04 kJ·mol^(-1)。在质子酸存在的条件下,乙酰胺可以首先发生质子化,然后与NO_(3)^(-)形成络合物,随后游离的NO_(2)^(+)进攻酰胺氮原子,酰胺键断开并生成硝胺化合物,该反应的活化能为41.65 kJ·mol^(-1),反应放热147.31 kJ·mol^(-1),酸催化硝化比直接硝化的活化能更低。The nitrolysis mechanism of the nitrolysis of tetraacetylhexaazaisowurtzitane(TAIW)with the nitrolytic agent of N_(2)O_(5) were studied with respect to the synthesis of hexanitrohexaazaisowurtzitane(CL-20).TAIW was nitrolyzed in nitrolysis systems with and without acid to prove that acetamide of TAIW might be nitrolyzed into nitramine only in an environment with protonic acid.The mechanism of acetamide nitration for tetraacetyldinitrobenzane(TADN)was studied at B3LYP/6-31G(d,p)level based on the density functional theory(DFT).Two possible transition states for the reaction path were identified.The results showed that NO_(2)^(+)nitrified the acetamide directly with the assistance of NO_(3)^(-),the activation energy was 134.04 kJ·mol^(-1).In the presence of protic acid,the acetamide first protonated,and then formed a complex with NO_(3)^(-).Subsequently,the free NO_(2)^(+)attacked the nitrogen atom in amide.Thus,the amido bond was broken,and a nitramine compounds was produced.For the reaction,the activation energy was 41.65 kJ·mol^(-1),and the reaction exotherm was 147.31 kJ·mol^(-1),The activation energy for acid catalyzed nitrification was lower than that for direct nitrification.

关 键 词：五氧化二氮 四乙酰基六氮杂异伍兹烷 反应机理 密度泛函 

分 类 号：O626.2[理学—有机化学]