一个DFT比较C-C减速合从终端化和化复合体的
Roberto Escobar1, Jessica Meza1, Javier Pena1
1School of Integrative Biological and Chemical Sciences, The University of Texas Rio Grande Valley, Edinburg, Texas 78541, United States.
Inorganic chemistry
|August 28, 2024
概括
密度函数理论揭示了一个 σ-CC 复合体作为催化和酸连接体的还原性合中的关键中间体. 这与以前对蓝化合物复合物的发现形成鲜明对比,为C-C键形成机制提供了新的见解.
科学领域:
- 有机金属化学 有机金属化学
- 计算化学计算化学
- 催化剂是一种催化剂.
背景情况:
- 之前的研究已经确定了 η2 - 烯复合物作为Ni C-CN还原合的中间体.
- 了解还原性合机制对于设计新的催化过程至关重要.
研究的目的:
- 为了研究终端化物和化物复合物的热C-C还原合与[Ni(dmpe) ].
- 阐明关键的反应中间体,并将其与已知的Ni C-CN系统进行比较.
- 探索不同金属碎片和连接体对反应路径的影响.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 对反应中间体和过渡状态的分析.
- 热力学和激活能计算.
- 自然人口分析 (NPA).
主要成果:
- 一个 σ-CC 复合物被确定为化和化联接的关键中间体,与[Ni(dmpe) 结合.
- 化物合是内热的,具有高激活屏障,而化物合是外热的,具有较低的屏障.
- 使用[Pt(dmpe) 和[Pt(dmpm) ]片段进行的计算与C-CP债券激活率和反反应率的实验观测相一致.
- 自然种群分析表明 ΔG° 符号的反转与 C-C 债券极性反转.
结论:
- 反应中间体在Ni C-CN和Ni C-CP减速合系统之间有所不同.
- 电子性质和连接体环境显著影响减速合的热力学和动力学.
- DFT提供了对反应机制的宝贵见解,补充了实验数据.
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