乙酰苯胺和对氨基苯乙酮单分子离子分解机理  

Study on Unimolecular lon Decomposition Reaction Machanism of Acetanilide and p-maminoacetophenone

作　　者：赵邦蓉[1] 鲁崇贤 叶学其[2] 

机构地区：[1]北京化工大学应用化学系,北京100029 [2]中国科技大学研究生院,北京100039

出　　处：《物理化学学报》1998年第5期419-423,共5页Acta Physico-Chimica Sinica

摘　　要：从实验和理论两方面对乙酰苯胶和对氨基苯乙酮单分子离子分解反应机理进行研究．在实验方面，采用质谱仪器的磁场／静电场联动扫描检测了两个化合物的亚稳峰，得到化合物在质谱中的分解途径．在理论方面，根据分子轨道理论，用3－21基组从头计算研究分解反应中的能量变化．获得了分解产物的总能量与前体离子的总能量之差△E，按照产物的稳定性和能量有利的原则，在竞争的分解反应中，△E最小的分解反应占优势．计算的结果与质谱实际分析的结果一致．The mechanism of unimolecular ion dccomposition reaction of acetamliide and p-aminoasetophenone has been studied from both the experimental and the theoretical aspects. Ex-perimentally metastahle peaks were determmed by lined scan of magnetnc field and electrostaticfield in mass spectrometer. Decomposition pathway of the two compounds in mass spectrometerwas obtained theoretically, on the basis of molecular orbital theory, ab initio calculations with the3-2l basis sets hate been used to investigate the variations of energy in reactions. Total energydifference (△E) between parent ion and decomposition product was obtained hy calculation. Ac-cording to the principle of the stability of product and of favourable energy, the reaction of least'△E is dominat in the competitive decomposition reactions. Calculated result and that, of analysisby mass spectrometry are in aggrement.

关 键 词：单分子 离子分解 质谱 乙酰苯胺 对氨基苯乙酮 

分 类 号：O625.632[理学—有机化学] O625.635[理学—化学]