在Pd(II) -F转化为Pd(II) -CF的过渡后状态动态效应3
Maoping Pu1, Christian D-T Nielsen1, Erdem Senol1
1Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany.
JACS Au
|January 26, 2024
概括
揭示了催化三甲基化中的过渡后状态动态. 溶剂和试剂决定反应路径,通过不同的机制形成cis或trans-Pd(II) CF3物种.
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.
- 计算化学计算化学
背景情况:
- 在基于金属的转换中,很少观察到过渡状态后的动态效应.
- 对于催化合反应,以前没有报告动态效应.
研究的目的:
- 为了研究Pd(II) F的三甲基化,这是Pd(0) /Pd(II) 催化三甲基化中的关键步骤.
- 为了阐明cis/trans Pd(II) CF3物种化的溶剂和传递试剂依赖性.
- 探索由介导的三甲基化过程的机制和动态.
主要方法:
- 实验研究Pd (II) F三甲基化.
- 使用GFN2-xTB和B3LYP-D3分子动力学 (MD) 模拟的计算研究.
- 波恩-奥本海默MD模拟与或没有明确的solvation.
- 高层次的量子力学 (QM) 计算.
主要成果:
- 溶剂和传递试剂显著影响 cis/trans Pd (II) CF3 变种.
- 在中,二碳基的形成和随后与Pd的重组通过两个途径发生.
- 在极性溶剂 (MeCN) 中,一种离子对机制占主导地位,涉及CF3离子和Pd (II) 离子.
- 一个单一的过渡状态导致 cis 和 trans 异构体由于过渡后的状态分叉.
- 自由氨酸抑制了Pd的cis-to-trans同质化 (二) CF3.3.
结论:
- 该研究揭示了催化三甲基化中的新型过渡后状态动态效应.
- 反应机制高度依赖于反应介质和转移试剂.
- 了解这些动态对于控制介导反应中的产品选择性至关重要.
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