在DPT辅助的转移化微动力学研究中,对同质和固定的Cp*Ir复合体进行了转移化
Ivan Mitrichev1, A John Blacker2,3, Michael Chapman2
1Information Computer Technologies Department, D. Mendeleev University of Chemical Technology of Russia, 9 Miusskaya sq., Moscow 125047, Russia.
The journal of physical chemistry. A
|March 3, 2025
概括
密度函数理论的计算揭示了使用催化剂进行甲转移化的内球机制. 固定催化剂由于有限的复杂参与,其活性较低.
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:
- 甲转移化是有机合成中的一个关键反应.
- 复合物,如[Cp*IrCl2]2,是这种转变的有效催化剂.
- 了解反应机制对于催化剂优化至关重要.
研究的目的:
- 使用[Cp*IrCl2]2.2. 调查甲转移化的动力机制.
- 为了比较同质和固定催化剂的活性.
- 开发一个数学模型来模拟反应动力学和催化剂性能.
主要方法:
- 密度函数理论 (DFT) 计算用于预测不同机制 (内部球,外部球,MPV) 的能量障碍.
- 使用均质和固定Cp*Ir催化剂的动力学研究.
- 开发一个数学和微动力学模型,结合DFT结果和实验数据.
主要成果:
- 内部球体 (IS) 机制的有效屏障为53.0kJ/mol,优于外部球体 (OS) 和Meerwein-Pondorf-Verley (MPV) 机制.
- 模拟预测只有约25%的固定复合物是活跃的,这解释了与同质催化剂相比较低的活性.
- 固定催化剂活性与化物种度相关,受度的影响.
结论:
- 内球机制是甲转移化与[Cp*IrCl2]2.2的主要途径.
- 在固定催化剂中,活动部位的有限可访问性大大降低了它们的整体活性.
- 优化基度对于提高固定化催化剂性能至关重要.
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