允许和禁止的机械化学环开放反应中的替代作用
Cameron L Brown1, Brandon H Bowser1, Jan Meisner2,3
1Department of Chemistry, Duke University, Durham, North Carolina 27708, United States.
Journal of the American Chemical Society
|March 5, 2021
概括
研究了循环布丁和循环布丁环开放反应中的替代作用. 这项研究揭示了力修改路径中的"反应性翻转",影响了允许和禁止的电循环反应.
科学领域:
- 机械化学
- 聚合物化学
- 有机化学
背景情况:
- 共价聚合物机械化学的领域是从发现"麦克斯韦尔恶魔" (Maxwell demon) 引发的,使力修饰反应成为可能.
- 在过去的十年中,已经建立了对电环开放反应的力修改路径的基本理解.
研究的目的:
- 扩大对循环布丁 (CBE) 和循环布丁 (BCB) 的允许和禁止环开反应的替代作用的理解.
- 研究替代剂对力诱导电循环反应的能量和机制的影响.
主要方法:
- 采用单分子力光谱 (SMFS) 来探测施加力下的反应路径.
- 使用计算分析来阐明环开放反应的机制和能量格局.
- 与不同替代物模式的环丁烯和环丁烯衍生物的行为进行了比较.
主要成果:
- 观察到"反应性翻转",其中cis-benzocyclobutene的禁止环开放发生在低于允许的trans-benzocyclobutene环开放的力下.
- 对 cis- 和 trans- cyclobutene 观察到相反的趋势,允许的反应是在较低的力度下进行的.
- 计算分析通过"允许/禁止差距"概念来解释这些反应性差异.
结论:
- 替代效应显著影响环丁烯和环丁烯衍生物的机械化学反应性.
- 这项研究为控制力驱动的有机反应中的立体化学和反应途径提供了关键的见解.
- 这些发现促进了对共价聚合物机械化学及其潜在应用的基本理解.
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