通过环重组稳定pi-结合基素
Baolin Li1, Tsukasa Matsuo, Daisuke Hashizume
1Functional Elemento-Organic Chemistry Unit, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Journal of the American Chemical Society
|September 1, 2009
概括
合成了新的含有上基的基素. 独特的结构,由八甲基-s-氨酸-4-yl (Eind) 基稳定,使扩展pi-conjugation,通过DFT计算和光谱学证实.
科学领域:
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 对于有机电子和材料科学而言,pi-结合系统至关重要.
- 含有-双键的酸化合物具有独特的电子性质.
- 活性物种的稳定是它们的合成和应用的关键.
研究的目的:
- 用各种替代剂合成新型pi-结合基素.
- 研究这些化合物的结构,电子和光学特性.
- 探索八甲基-s-氨酸-4-yl (Eind) 组在稳定素框架中的作用.
主要方法:
- 使用1,1,3,3,5,5,7,7-octaethyl-s-hydrindacen-4-yl (Eind) 连接物合成素.
- 进行X射线结构分析以确定分子几何和pi框架平面性.
- 紫外线-Vis光谱法观察pi-pi*吸收并评估结合长度.
- 密度函数理论 (DFT) 计算用于分析边界分子轨道和结合路径.
- 电化学测量以描述氧化还原特性.
主要成果:
- 通过Eind部分稳定,在上成功合成了具有各种基的酸.
- X射线分析显示了一个高度共平面的pi框架,垂直定向的Eind群提供了硬质保护.
- 强大的pi-pi*吸收表明在分子骨架中扩展了pi-conjugation.
- DFT的计算证实了在最低的无人分子轨道 (LUMO) 中的- (Si-P) 3p(pi) 和碳pi电子系统之间的显著结合.
结论:
- 埃因德组有效地稳定了pi-结合的素,使平面结构的形成成为可能.
- 实现了扩展的pi-conjugation,从而产生了特有的光学吸收特性.
- 电子结构显示了-和碳pi系统之间的显著相互作用,这与光电子应用有关.
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