通过内分子维尔斯迈耶反应合成和分离抗芳香膨胀阿扎科罗
Kosuke Oki1, Masayoshi Takase1, Shigeki Mori2
1Graduate School of Science and Engineering , Ehime University , Matsuyama 790-8577 , Japan.
Journal of the American Chemical Society
|October 3, 2019
概括
研究人员合成了一种扩展的六罗赫萨科罗 (HPHAC) 的反芳香离子. 这种新型化合物表现出24π的反芳香性,通过NMR光谱和计算研究得到证实,并且可以转化为芳香三基.
科学领域:
- 有机化学
- 材料科学
- 计算化学
背景情况:
- 扩增六环 (HPHAC) 是一类具有独特电子性质的宏环化合物.
- 研究HPHAC衍生物的芳香性和电子行为对于开发新的功能材料至关重要.
研究的目的:
- 合成和描述HPHAC的一种新型抗芳.
- 阐明合成的阳离子的电子结构和反芳香性.
- 探索氧化还原特性和转化为芳香系统的潜力.
主要方法:
- 用于合成HPHAC的维尔斯迈尔类反应.
- 用于结构确定的X射线衍射分析.
- 质子核磁共振 (1H NMR) 谱法用于评估电子特性.
- 计算方法 (核独立的化学转移和诱导电流密度的异构性) 用于全球抗芳性评估.
- 循环电压测量用于氧化还原行为分析.
主要成果:
- 成功合成扩展HPHAC的反芳香单离子 (1).
- 通过X射线衍射证实有7个环形与甲结合.
- 一个小时的NMR光谱显示出显著的上场转移,证实了24π的反芳香性.
- 计算研究证实了全球的反芳香性质.
- 循环测量显示了两个可逆的氧化和一个不可逆的减少.
- 用NOSbF6进行的治疗产生了芳香三 (22π电子结合).
结论:
- 合成的HPHAC单离子是一种稳定的抗芳香物种.
- 这项研究表明一种合成途径可以获得抗芳香HPHAC衍生物.
- 这些发现突显了HPHAC系统的可调节电子特性,允许在反芳香和芳香状态之间进行转换.
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