六基的合成,结构和特性:将六个 [5] 基组合成高度扭曲的芳香系统
Tomoka Hosokawa1, Yusuke Takahashi1, Tomoya Matsushima2
1Department of Chemistry, Graduate School of Science, Osaka Prefecture University , Sakai, Osaka 599-8531, Japan.
Journal of the American Chemical Society
|September 7, 2017
概括
研究人员合成了六聚烯分子,这些复杂的分子有六个 [5] 烯单元. 它们选择性地形成一个同位素 (HH-1),该同位素形成一个更稳定的形式 (HH-2),显示出独特的结构和电子性质.
科学领域:
- 有机化学
- 超分子化学
- 材料科学
背景情况:
- 六聚烯是复杂的多环芳,具有六个 [5]基结构.
- 它们的合成和立体异构在分子设计中提出了重大挑战.
- 了解它们的结构和电子特性对于先进材料的应用至关重要.
研究的目的:
- 通过催化循环添加反应合成新型六基.
- 研究合成化合物的立体异构,结构特征和电子性质.
- 研究六聚烯异构体的热异构化和种族化动力学.
主要方法:
- 催化 [2+2+2] 循环添加反应进行合成.
- 密度函数理论 (DFT) 对同位素稳定性和电子性质的计算.
- 单晶X射线衍射用于结构阐明.
- 化高性能液体染色学 (HPLC) 用于分离反体.
- 核磁共振 (NMR) 光谱用于运动研究.
主要成果:
- 从基前体中选择性合成六聚乙烯HH-1.
- 确定HH-1为第二稳定的同位素,量化为最稳定的HH-2.
- 使用奇拉HPLC分离HH-2反体.
- 通过X射线衍射确定不同的状 (HH-1) 和螺旋状 (HH-2) 结构.
- 在HH-1中观察到显著的结构扭曲,扭曲角度很大 (每本单位高达35.7°).
- 由于扩展的π-系统,HOMO-LUMO差距较小,电化学和DFT证实了这一点.
- 对HH-1到HH-2异构和HH-2种族化的动力学研究.
结论:
- 成功合成具有独特结构特征的六螺旋体.
- 对潜在应用的受控异构和反体分离的演示.
- 阐明结构属性关系,突出光电子材料的潜力.
- 确定异构体相互转换和种族化的动态途径.
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