用基转化合成的摩比乌斯三环的动力控制
Xing Jiang1, Joshua D Laffoon2, Dandan Chen3
1Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|March 27, 2020
概括
研究人员使用基转化合成了莫比乌斯宏循环,实现了高产量,并证明了对热力学稳定的动力控制. 这项工作为创建复杂,扭曲的分子结构开辟了新的途径.
科学领域:
- 有机化学
- 超分子化学
- 材料科学
背景情况:
- 由于它们的复杂,扭曲和宏循环结构,合并的莫比乌斯分子的合成存在重大挑战.
- 这些架构的低性质进一步复杂化了它们的准备.
研究的目的:
- 报告一个新的莫比乌斯宏观循环的合成.
- 研究基转化循环聚合反应的运动选择性.
- 描述合成分子的电子特性和芳香性.
主要方法:
- 2,13-bis(propynyl) [5]的基转化.
- 矩阵辅助激光脱离/电离质谱法 (MALDI-MS).
- 核磁共振 (NMR) 光谱学
- 进行X射线衍射分析.
- 密度函数理论 (DFT) 的计算.
- 计算研究 (ACID和EDDB).
- 紫外线和光光谱.
- 循环电压测量
- 基质高性能液体染色学 (HPLC).
主要成果:
- 在84%的产量中成功合成了莫比乌斯宏观循环.
- 鉴定发现具有双重对称性 (PPM/MMP配置) 的三元制物.
- DFT计算显示了更稳定的热力学三重对称PPP/MMM结构,突出了动力选择性.
- 计算研究显示激活屏障的差异为15.4kcal/mol,这解释了运动偏好.
- 电子研究显示结合性较弱,缺乏显著的整体芳香度.
- 通过奇拉HPLC实现了PPM和MMP的分离.
结论:
- 这项研究通过基转化证明了Möbius宏循环的成功和高产合成.
- 在循环聚合过程中观察到显著的运动选择性.
- 合成的分子具有有限的电子结合和全球芳香度.
- 梅比乌斯宏循环的反体分离成功进行.
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