无氧化反应的机制:一项DFT研究
Robert D Bach1, H Bernhard Schlegel2
1Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States.
The journal of physical chemistry. A
|March 7, 2024
概括
沙普莱斯反应使用催化剂进行选择性环氧化. 计算建模显示,一个二维催化剂是最受欢迎的,在这个关键的有机合成方法中增强了反应性和选择性.
科学领域:
- 有机化学 有机化学
- 计算化学计算化学
- 催化剂是一种催化剂.
背景情况:
- 沙普勒斯反应是对合醇的酶选择性环氧化的一个关键方法.
- 这种反应使用 (IV) 催化剂系统,其中包括四氧化,二甲基酸盐 (DET) 和三甲基丁氧化.
- 了解催化机制对于优化酶选择性和反应效率至关重要.
研究的目的:
- 使用DFT.模拟夏普勒斯环氧化反应的结构和能量.
- 研究 (IV) 催化剂的二元化及其对反应性的影响.
- 阐明过渡结构,激活能量,以及影响enantioselectivity因素.
主要方法:
- 密度函数理论 (DFT) 计算使用M06-2X函数和6-311+G(d,p) 基础集.
- 模拟催化剂结构,配体交换反应和环氧化过渡状态.
- 激活能量的分析以及特定分子相互作用和二面角的影响.
主要成果:
- 单体 ((IV) 甲基酸盐催化剂强烈支持二聚化到更具反应性的五坐标物种,[Ti ((DET) ((O-i-Pr) ]2.2.
- 对于催化循环至关重要的配体交换反应具有较低的激活能.
- 确定了各种醇的对抗选择性环氧化过渡结构和激活能.
- 这项研究强调了C=O---Ti相互作用和O-C-C=C二面角在enantioselectivity中的作用.
结论:
- 双面复合体是夏普莱斯环氧化过程中的活性催化剂.
- 计算建模提供了对反应机制的详细见解,以及控制酶选择性的因素.
- 这项工作有助于更深入地了解不对称催化和夏普勒斯反应.
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