直接观察到从单体阿里拉 (II) 化物复合物中化的还原性消除
1Department of Chemistry, Yale University, P.O. Box 208107, New Haven, CT 06520-8107, USA.
Journal of the American Chemical Society
|November 13, 2003
概括
的烯化合物复合物 (II) 经过了还原性淘汰. 化物电子性质,而不是热力学,决定了化,化和化的减少消除率.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 反应机制 反应机制
背景情况:
- 单质,三坐标的烯 ((II) 化物复合物是各种催化过程中的关键中间体.
- 从复合体中减少消除烯化物,形成烯和Pd(0).
研究的目的:
- 研究从 (II) 复合物中减少性消除化 (化物,化物,化物,化物) 的方法.
- 确定控制这些反应的速度和热力学因素.
主要方法:
- 合成单体烯 (((II) 化物复合物与P(t-Bu) 3连接体.
- 在添加P(t-Bu) 后,观察减少性消除3.
- 建立了与五种光相结合的降解性消除和氧化性添加的平衡条件.
主要成果:
- 观察到化,化和化的减少性消除.
- 热力学有利于减少的消除:化物 > 化物 > 化物.
- 减少性消除的动力率:化物 > 化物 > 化物.
- 化物电子特性,而不是热力学驱动力,控制反应速率.
结论:
- 化物联体的电子性质是化复合体中减少性消除速率的主要决定因素.
- 机理学研究表明,在最初的减少性消除后,涉及P(t-Bu) 3的速度限制协调步骤.
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