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含有二博的pi电子系统:基于p(pi) -pi*结合的"开/关"控制的显著光变化
Shigehiro Yamaguchi1, Toshiaki Shirasaka, Seiji Akiyama
1Institute for Chemical Research, Kyoto University, and PRESTO, Japan Science and Technology Corporation, Uji, Kyoto 611-0011, Japan. shige@scl.kyoto-u.ac.jp
Journal of the American Chemical Society
|July 26, 2002
概括
新的二博衍生物在对溶剂和离子的反应中表现出显著的光变化. 这表明它们作为化学传感应用中的敏感光探针的潜力.
科学领域:
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
- 光物理学的光学物理学
背景情况:
- 由于其独特的电子和光学特性,研究了二博醇衍生物.
- 在开发先进的功能性材料方面,Solvatochromism和离子感应能力至关重要.
研究的目的:
- 合成具有多种功能组的新型二博衍生物.
- 研究它们的光物理特性,包括solvatochromism和离子感应行为.
- 了解观察到的光变化背后的机制.
主要方法:
- 双博醇衍生物的化学合成.
- 光谱分析 (UV-Vis吸收和光发射).
- 通过各种有机溶剂 (例如THF,DMF) 进行Solvatochromic研究.
- 使用四甲基化物 (n-Bu4NF) 的离子传感实验.
主要成果:
- 成功合成了含有 (N,N-diphenylamino) -phenyl,thienyl和bithienyl部分的二博醇衍生物.
- 观察到显著的溶色效应,在极性溶剂中排放最大值的蓝色转移 (100-140nm) 和增强的量子产量 (20-30倍) 显著.
- 对化物离子的感知能力得到证明,在n-Bu4NF添加后,类似的光光谱变化证明了这一点.
- 光调制归因于通过对原子的协调在LUMO中的pi-pi*对合的"开/关"控制.
结论:
- 合成的二博衍生物显示出对光传感有前途的光物理特性.
- 它们对溶剂极性和离子的敏感性突出显示了它们在开发新型化学传感器方面的潜力.
- 观察到的光反应是由二博核的中心的电子相互作用控制的.
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