双波长可切换的分子自组合光酸和spirooxazine在水溶液中的
Alexander Zika1, Mohit Agarwal1,2, Ralf Schweins2
1Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, Bavarian Polymer Institute, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, D-91058 Erlangen, Germany.
The journal of physical chemistry letters
|October 20, 2023
概括
研究人员使用两个光开关创建了四重切换的纳米级组件. 这些组件响应特定的波长,pH值和黑暗,从而实现先进的分子控制.
科学领域:
- 超分子化学 超分子化学
- 纳米技术纳米技术
- 摄影化学的使用.
背景情况:
- 分子光开关对于开发响应性材料至关重要.
- 控制纳米级组件需要精确的外部刺激.
- 结合不同的光开关机制提供了新的功能.
研究的目的:
- 为了构建四重切换的纳米级组件.
- 为了利用双极-双极相互作用形成组件.
- 为了实现对组件的波长特定控制.
主要方法:
- 合成的水溶性分子光开关.
- 利用双极-双极相互作用形成纳米级组件.
- 采用波长特定的光辐射和pH值变化作为刺激.
主要成果:
- 成功构建了四重切换的纳米级组件.
- 证明了一种光酸的波长特定的质子解离.
- 展示了一种阳离子螺旋的环开放.
- 通过两种不同的波长,pH和黑暗来实现组装控制.
结论:
- 可四次切换的纳米级组件可以通过组合光开关来构建.
- 双极双极相互作用对于构建这样的组件是有效的.
- 这些组件表现出对光和pH值的响应行为,提供精确的控制.
相关概念视频
01:26Photochemical Electrocyclic Reactions: Stereochemistry
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
01:11Aryldiazonium Salts to Azo Dyes: Diazo Coupling
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.
01:12Cycloaddition Reactions: MO Requirements for Photochemical Activation
Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.