替代剂对循环基基,循环基,同基和循环基子之间的平衡的影响
Sean P Larmore1, Pier Alexandre Champagne1
1Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States.
The Journal of organic chemistry
|May 16, 2024
概括
研究了替代剂对C4H7+离子平衡的影响. 电子捐赠组有利于特定的结构,而电子吸收组创建可访问的混合物,影响反应产品.
科学领域:
- 有机化学 有机化学
- 计算化学计算化学
- 反应机制 反应机制
背景情况:
- 环基 (CPC) 和双基 (BCB) 离子是产生环基,环基或同基产物的反应中的关键中间体.
- 核友反应中的立体特异性通常会受到多个相关的C4H7+离子结构 (BCB,CPC,cyclobutyl,homoallyl) 之间的平衡影响.
研究的目的:
- 研究替代剂对单替代和多替代C4H7+离子平衡的电子和硬质效应.
- 了解替代物模式如何影响潜在能量表面和不同离子结构的相对稳定性.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 具有双激发的区别线性合集群 (DLPNO-CCSD(T)) 的计算.
- 使用哈梅特相关性 (σ+) 的替代效应分析.
主要成果:
- 对于C4H7+的潜在能量表面 (PES) 对替代物非常敏感;对于一个替代物来说最小的结构可以成为另一个替代物的过渡状态.
- 电子捐赠组根据它们的位置 (C1,C2或C3/C4分别) 稳定了CPC,BCB/环丁基和同基结构.
- 电子吸收组导致具有多个可访问的阴离子结构的较浅的PES,并且替代物效应是附加的,与哈梅特参数 (σ+) 相对应得很好.
结论:
- 这项研究提供了一个预测框架,以了解基于替代物模式的平衡中占主导地位的C4H7+离子结构.
- 这些预测可以指导我们理解涉及这些复杂离子平衡的反应中主要产物形成的情况.
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