Relative thermodynamic stabilities of 3-ethylidenecyclohexenes and isomeric ethylcyclohexadienes
作者:Esko Taskinen、Kari Nummelin
DOI:10.1016/s0040-4020(01)85662-3
日期:1994.1
The relative thermodynamic stabilities of the E and Z forms of 3-ethylidenecyclohexene, 1-ethyl-1,3-cyclohexadiene, 2-ethyl-1,3-cyclohexadiene and 1-ethyl-1,4-cyclohexadiene were determined by t-BuOK catalyzed chemical equilibration in DMSO solution. From the variation of the equilibrium composition with temperature the enthalpy, entropy and Gibbs energy differences between the isomeric species were
通过t- BuOK测定3-亚乙基亚环己烯,1-乙基-1,3-环己二烯,2-乙基-1,3-环己二烯和1-乙基-1,4-环己二烯的E和Z形式的相对热力学稳定性。在DMSO溶液中催化化学平衡。根据平衡组成随温度的变化,评估了异构体之间的焓,熵和吉布斯能量差。亚乙基环己烯被发现是热力学平衡最丰富的物质,这是由于它们的焓值低9–12 kJ mol -1。然而,熵项有利于环己二烯7–11 JK -1 mol -1。