丧的易斯对的反应性:碳酸与激进中间体对比
Zheng-Wang Qu1, Hui Zhu1, Stefan Grimme1
1Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115, Bonn, Germany.
Chemistry (Weinheim an der Bergstrasse, Germany)
|December 20, 2023
概括
丧的易斯对 (FLP) 可能不是主要形成C-C合的基. 相反,DFT计算显示,碳酸转移更有利,为FLP反应性提供了新的见解.
科学领域:
- 计算化学计算化学
- 有机金属化学 有机金属化学
- 丧的易斯对 (FLP) 是一个
背景情况:
- 最近的研究提出单电子转移 (SET) 和激素形成是挫败的易斯对 (FLP) 化学中的关键机制,特别是在C-C合反应中.
- 激素通路在FLP介导的C-C键形成中的作用一直是化学界正在进行的调查和辩论的主题.
研究的目的:
- 研究涉及大量素,基酸和易斯酸如三 () (BC6F5) 3) 的反应的机械路径.
- 在FLP化学中计算评估激素与非激素路径的动力优势,特别是关于C-C合和碳酸转移.
主要方法:
- 广泛的分散校正密度功能理论 (DFT) 计算被用来建模反应路径并确定动力障碍.
- 分析的重点是产生反应性中间体,包括基基,基离子和离子.
- 对拟议的激素C-C合和碳酸转移机制进行了热力学和动力学评估.
主要成果:
- DFT计算表明,虽然可以形成基基和基离子,但直接的P-C异质合形成离子是动态偏好的.
- 这些酸作为有效的碳酸转移试剂作用于像烯这样的基质,这种途径明显比拟的激素C-C合更有利.
- 超稳定基离子盐,如Mes3P+•,通过涉及Mes3P,B(C6F5) 3和p-O2C6Cl4.4.3等特定氧化剂的SET反应可以通过动力学来获得.
结论:
- 该研究挑战了某些FLP系统中根基主导的C-C合的普遍概念,强调了碳酸转移机制的重要性.
- 分散校正的DFT计算为FLP反应的动态格局提供了关键的见解,在特定条件下有利于非激进路径.
- 这些发现建议重新评估FLP化学中提出的基因机制,并强调酸作为反应性中间体的多功能性.
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