基于Chan-Lam的以太化反应中的机械途径:一个计算探索
Thangaiyan Pooventhiran1, Nripen Khilari1, Debasis Koley1
1Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, 741 246, India.
Chemistry (Weinheim an der Bergstrasse, Germany)
|October 5, 2023
概括
这项研究使用DFT计算来揭示铜催化Chan-Lam以太化机制. 确定速率的步骤涉及转移,富含电子的系统显示出更高的反应回转率.
科学领域:
- 有机化学 有机化学
- 计算化学的计算化学
- 催化剂是一种催化剂.
背景情况:
- 陈拉姆 (CL) 合反应,特别是C-O键的形成,在有机合成中至关重要.
- 在Cu (II) 催化有氧氧化合的进步改善了基于CL的协议.
- 详细的机理性了解CL以太化,包括能量,仍然不完整.
研究的目的:
- 通过使用DFT计算,阐明基于Chan-Lam (CL) 的以太化过程的机械路径.
- 确定催化循环中的速度决定性步骤和关键中间体.
- 为了研究基板电子对反应效率的影响.
主要方法:
- 密度函数理论 (DFT) 引导的计算研究.
- 分析催化循环步骤及其激活障碍.
- 哈梅特研究了替代的烯乙烯 Ester.
主要成果:
- 确定了一种Cu(II) 中间体作为静止状态,转基因作为速率决定的步骤 (20.4 kcal/mol激活障碍).
- 催化循环中的后续步骤具有较低的能量跨度.
- 富含电子的阿里尔系统表现出更高的反应回转率,与实验数据一致.
- 预计大多数酒精基质的中度至高乙化回转率,其中环醇是例外.
结论:
- 这项研究提供了对Cu (II) 催化Chan-Lam乙化机制的基本见解.
- 计算发现澄清了关键步骤的能量,特别是传输.
- 结果支持实验观测,并为基质范围和效率提供预测能力.
相关概念视频
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