关于双分子SNAr反应的协同和阶段机制之间的边界的计算研究
Simon Rohrbach1, John A Murphy1, Tell Tuttle1
1Department of Pure and Applied Chemistry, University of Strathclyde 295 Cathedral Street, Glasgow G1 1XL, United Kingdom.
Journal of the American Chemical Society
|August 14, 2020
概括
核友芳香替代 (SNAr) 反应的机制可以分阶段或协调. 这项研究确定了关键因素,包括电子亲和力,以预测哪种机制有利于化.
科学领域:
- 有机化学
- 反应机制
- 计算化学
背景情况:
- 双分子核芳香替代 (SNAr) 反应传统上通过涉及迈森海默中间体的阶段性机制进行.
- 对SNAr反应的协同机制得到越来越多的认可,但对影响机理选择的因素缺乏全面的理解.
- 现有研究提供了协同SNAr反应的孤立例子,需要一个更清晰的框架来预测反应途径.
研究的目的:
- 确定SNAr反应中分阶段和协调机制之间的选择的关键因素.
- 根据基质特性建立一个预测模型来确定首选的反应途径.
- 阐明SNAr反应的机制,特别是对于化基质.
主要方法:
- 对SNAr反应路径的理论分析.
- 确定影响反应机制的主要电子和结构因素.
- 使用电子亲和力作为机械预测的描述.
主要成果:
- 已经确定了影响SNAr反应的关键因素.
- 化基质的电子亲和力被证明是预测反应机制的简单但有效描述因素.
- 对SNAr反应建立了一个更清晰的机制图片,超越了孤立的例子.
结论:
- 在SNAr反应中,逐步和协调的机制之间的选择是由特定的,可识别的因素决定的.
- 电子亲和度提供了一种有价值和易于使用的工具,用于预测化是否会通过协调或阶段性途径经历SNAr.
- 这项工作有助于更统一地了解SNAr反应机制.
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