通过Pt-Sb复合体对基化酸氧化的机械研究
Christopher K Webber1, Jugal Kumawat2, Fanji Kong1
1Department of Chemistry, University of Virginia; Charlottesville, Virginia 22904, United States.
Organometallics
|March 14, 2025
概括
复合物催化了1,2-二乙烯 (DCE) 的C-Cl乙氧化. 复合体1的反应速度比复合体2更快,DFT计算揭示了潜在的反应机制.
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:
- 复合物与酸盐连接体可以调解有机转化.
- C-Cl 键激活是许多合成过程中的关键步骤.
- 了解反应路径对于催化剂设计至关重要.
研究的目的:
- 通过使用新型乙酸盐复合物,研究1,2-二乙烯 (DCE) 的乙氧化.
- 为了比较DCE乙氧化中的不同复合物的催化活性.
- 为了阐明介导的C-Cl键功能化的机制.
主要方法:
- 二酸盐复合物的合成和表征.
- 在超额DCE的伪第一阶条件下进行的动力学研究.
- 单晶X射线衍射用于中间体的结构性确定.
- 密度函数理论 (DFT) 计算以探索反应机制.
主要成果:
- 复合物 (SbQ3) Pt ((OAc) 2 (1) 和 (SbQ2Ph) Pt ((OAc) 2 (2) 被合成并测试了DCE的乙氧化.
- 与复合体2 (k_obs = 0.51 × 10^-4 s^-1) 相比,复合体1的观察速率常数显著更高 (k_obs = 2.44 × 10^-4 s^-1).
- DFT计算表明了两个可信的机制:通过或直接酸盐替代的核友攻击,两者在能量上是可比的.
结论:
- 这项研究表明,乙酸盐复合物在催化DCE乙氧化过程中的有效性.
- 在中心的连接物修饰会影响催化活性.
- DFT计算为复合体的C-Cl键功能化的机制性途径提供了宝贵的见解.
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