摘要
采用分子模拟计算方法计算了二甲苯的分子轨道、3种二甲苯与H+之间的相互作用,以及二甲苯异构化过程中2种分子内反应机理的能量路径和过渡态。结果表明,苯环骨架异构(简称1,3-迁移)的过渡态路径比甲基在苯环上转移(简称1,2-迁移)路径复杂,且1,3-迁移路径过渡态最高能垒值220.5kJ/mol远高于1,2-迁移的过渡态最高能垒85.1kJ/mol。由此推测,甲基在苯环上转移的1,2-迁移为二甲苯分子内异构化反应的主要机理路径。
By using molecular simulation technologies,the molecular orbitals of xylene,the interactions of H＋ with xylene and the energy of each intermediate and transition state in xylene intramolecular isomerization（1,3-shift and 1,2-shift） were calculated and compared.The results showed that the mechanism of benzene ring transforming path（1,3-shift） was more difficult than the methyl shift path（1,2-shift）.The highest transition state energy of 1,3-shift was 220.5 kJ/mol,which was higher than that of 1,2-shift（85.1 kJ/mol）.It could be included that the 1,2-shift was the main mechanism for xylene intramolecular isomerization.
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
2012年第4期533-537,共5页
Acta Petrolei Sinica(Petroleum Processing Section)
关键词
二甲苯
异构化
分子轨道
过渡态
反应机理
xylene
isomerization
molecular orbital
transition state
reaction mechanism
