螺旋 - 结合侧向和纵向螺旋的结果是溶剂诱导的循环极化光的反转
Israa Shioukhi1, Harikrishna Batchu1, Gal Schwartz2
1Institute of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Edmond J. Safra Campus, 9190401, Jerusalem, Israel.
Angewandte Chemie (International ed. in English)
|January 15, 2024
概括
合并的乙烯中的螺旋性在烯和双烯之间不同. 将它们结合到heli-twistacenes中表明,twistacene螺旋体会影响电子光谱,导致溶剂诱导的信号逆转.
科学领域:
- 有机化学 有机化学
- 超分子化学 超分子化学
- 频谱学是一种光谱学.
背景情况:
- 合并的乙烯中的螺旋体在螺旋体和转体中明显表现出来.
- 螺旋体表现出恒定的螺旋体,而旋转场则提供可调的螺旋体和手性,通常受螺旋体的影响.
研究的目的:
- 通过结合基和刚性基来合成和表征新型基双烯分子.
- 研究将这些单元组合对分子螺旋性和手术性质的影响.
主要方法:
- 用X射线结晶学来确定结构完整性.
- 电子循环二极化 (ECD) 和循环极化发光 (CPL) 谱学用于分析手术特征.
- 罗西NMR和时间依赖密度函数理论 (TD-DFT) 计算用于结构和电子洞察力.
主要成果:
- X射线结构证实,链接保留了单个基和双基单元的螺旋性.
- ECD和CPL光谱在很大程度上受到twistacene单元的螺旋性调节.
- 在手术光谱中观察到溶剂诱导的信号逆转.
- 观察到的现象归因于基和双基部分之间的相对方向变化.
结论:
- 螺旋双代表了一种新的分子类别,其中结合的螺旋性影响了手术行为.
- 双烯部分在决定电子反应和光谱特征方面发挥着至关重要的作用.
- 了解这些结构-属性关系是设计先进的性材料的关键.
相关概念视频
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