叠氮二乙基铝三聚体和单体的缔合-解离平衡的研究  

Studies of Trimer-Monomer Equilibr ium of Diethyl Aluminum Azide

作　　者：高占先[1] 张小航[1] 冯立春[1] 

机构地区：[1]大连理工大学化工学院,大连116012

出　　处：《无机化学学报》2002年第7期654-658,共5页Chinese Journal of Inorganic Chemistry

基　　金：中国工程物理研究院基金资助(No.9505332)

摘　　要：尽管叠氮二乙基铝Et2AlN3(DEAA)是一个重要的化合物,但人们对它研究还是很少的。本文通过温度-蒸气压关系研究了纯态DEAA的三聚体和单量体之间的缔合-解离平衡;通过相对分子质量测定、核磁共振氢谱和核磁共振铝谱的测定,研究了在苯和甲苯溶液中DEAA的三聚体和单量体之间的缔合-解离平衡。借助温度-蒸气压曲线分别计算了DEAA三聚体和单量体的气化焓和解离焓;通过相对分子质量测定、核磁共振铝谱测定等方法计算得到了溶液中DEAA三聚体和单量体的解离平衡常数、解离焓和解离熵等热力学数据。The diethyl aluminum azide(DEAA)is an important compound in organic a luminum azides.But it was re-ported a little in the past.The temperature-vapor pressure dia gram of diethyl aluminum azide is determined in this work.There are two straight lines,(1)and(2),which intersected at 123Pa and 86.6℃in this diagram.There may be an equi -librium of trimer-monomer in the liq uid state DEAA(3):ln p=-3.760×10 4 /T+109.26(1)ln p=-1.014×10 4 /T+32.90(2)(DEAA) 3 3DEAA(3)Line(1)represents exchange from trimer of D EAA in liquid state to monomer in gas s tate.Line(2)represents exchange from monomer in liquid state to monomer in gas state.Thermodynamic data(ΔH (1) ,ΔH (2) andΔH d )of the DEAA have been calculated from th is two straight lines.The relative molecular weight of DEA A in benzene is determined by cryoscopic method.The relative molecular weight is always smaller than weight of(DEAA) 3 .This experiment demonstrates an eq uilibrium:(DEAA) 3 3DEAA(4)The 1 H NMR spectrum and the 27 Al NMR spectrum of DEAA are determined in toluene at different tempera-tures.The equilibrium(4)is demonstrated with the chemical sh iftsδ H andδ Al of DEAA.The thermodynamic data(equilibrium constant K d ?enthalpy exchangeΔH and entropy exchangeΔS)of the DEAA dissociation have also been calcula ted from these observed experimenta l values of relative molecular-weig ht de-termination and 27 Al NMR determination.These thermodynamic data calculate d in different methods are supported each other.

关 键 词：三聚体 单体 叠氮二乙基铝 相对分子质量 测定 核磁共振氢谱 核磁共振铝谱 缔合-解离平衡 

分 类 号：O627.3[理学—有机化学]