叠氮二乙基铝合成及其相关反应的研究

Investegation of Synthesis Reactio n and Relateve Reaction of Diethylal uminum Azide

在芳烃溶剂中用氯化二乙基铝和叠氮化钠反应合成了叠氮化二乙基铝(DEAA),其产率高达87%,比文献值高出17%。在正己烷中没有合成出DEAA,在含30%四氢呋喃(THF)的正己烷中合成出DEAA·THF配合物。在芳烃溶剂中,随着苯环上甲基数目的增加,DEAA的收率增加。测定了氯化二乙基铝、氯化二乙基铝的正己烷溶液、氯化二乙基铝的甲苯溶液的27AlNMR谱。由27AlNMR谱数据确定了氯化二乙基铝在甲苯中解离平衡式,计算了氯化二乙基铝在甲苯中解离平衡的热力学数据。用DEAA与苯甲酸甲酯直接合成了苯甲酰叠氮,并表征了其结构。这是一个新反应,至今无文献报导。用实验证明了在正己烷溶液中,用氯化二乙基铝、叠氮化钠与苯甲酸甲酯合成苯甲酰叠氮,没有经过氯化二乙基铝和叠氮化钠反应生成中间体DEAA的这一步。依据实验事实建立了上述三种反应的反应机理。

Diethyl aluminum azide(DEAA)is synthesized by the diethyl alumin um chloride and sodium azide in arene.The yield is 87%and that was reported in literature in 70%.The yield of DEA A is increased with methyl number in benzene ring increased.But,the DEAA did not obtain in n-hexane.The DEAA·THF complex is synthesized in solution 30%of THF and n-hexane.The 27 Al NMR of diethyl aluminum chloride i s determined,which is purified,in n-hexane,in toluene at 30℃and in toluene at 80℃,respectively.The thermodynamic data are calculated from 27 Al NMR spectral values for dissociation of dimer of dietyl alum inum chloride in toluene.The benzoyl azide is first synthesiz ed by DEAA and methyl benzoate.The benzoyl azide is charactered by IR spectrum and melting point measurem ent.This is a new reaction,which did not reported until now.In the preparation of benzoyl azide b y methyl benzoate,diethyl aluminum chloride and sodium azide in n-hexane,the intermediate product,DEAA,did not form from the reaction o f diethyl aluminum chloride and sodium azide.The conclusion has bee n confirmed by experimental results.The mechanisms of these three reacti ons has been given from experimental data above-mentioned.