Gas-Phase Kinetic and Mechanistic Studies of some Interconverting Alkylcyclopropene Pairs: Involvement of Dialkylvinylidene Intermediates and Their Quantitative Behaviour
作者:Wilhelm Graf von der Schulenburg、Henning Hopf、Robin Walsh
DOI:10.1002/1521-3765(20000602)6:11<1963::aid-chem1963>3.0.co;2-l
日期:2000.6.2
conversions up to 95% were obtained for the decomposition of each compound at five temperatures over a 40 degrees C range. The time-evolution data showed that the isomerisation reactions 15<==>16 and 5<==>17 were occurring. Kinetic modelling of each system allowed the determination of rate constants for these and all other decomposition processes. Tests confirmed that all reactions were unimolecular and homogeneous
烷基环丙烯的两个异构对的热解,即1,3-二甲基-(15)和1-乙基-环丙烯(16)和1,3,3-三甲基-(5)和1-异丙基-环丙烯(17) ,已经在气相中进行了研究。在40摄氏度范围内的五个温度下,每种化合物的分解均获得了高达95%的各种转化率的完整产品分析结果。时间演变数据表明发生了异构化反应15 = 16和5 = 17。每个系统的动力学建模可以确定这些以及所有其他分解过程的速率常数。测试证实,所有反应均为单分子且均质的。报告了总体反应和单个产物途径的阿累尼乌斯参数。进一步的动力学分析使我们能够提取出500 K时的倾向,重排涉及的二烷基亚乙烯基中间体的3-CH插入如下:k(prim):k(sec):k(tert)= 1:16.5:46.4。用13 C标记的环丙烯进行的其他实验产生的二烷基亚乙烯基的烷基迁移能力(来自炔烃产品中的13 C模式)如下:Me:Et:iPr = 1:3.1:1.5