工程阿佐衍生物控制光异构化过程
Flavia Aleotti1, Vasilis Petropoulos2, Hannah Van Overeem3
1Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna, Viale del Risorgimento 4, 40136 Bologna, Italy.
The journal of physical chemistry. A
|December 5, 2023
概括
亚博烯衍生物的结构特征显著影响光异构化. 分子内H键阻碍了它,而-醇复合体促进了它,指导了光开关设计.
科学领域:
- 摄影化学的使用.
- 分子设计分子设计.
- 频谱学是一种光谱学.
背景情况:
- 阿佐烯衍生物是光活性分子,在光开关中具有潜在的应用.
- 了解分子结构和光异构化之间的关系对于设计高效的光开关至关重要.
研究的目的:
- 为了研究结构特征,特别是分子内相互作用和共聚性,如何影响光激发状态行为和阿佐衍生物的 trans/cis 光异构化.
- 为设计具有可调节性能的基于亚博的光开关提供指导方针.
主要方法:
- 在可见近红外 (VIS-NIR) 区域进行高分辨率的短暂吸收实验.
- 量子化学计算,包括时间依赖密度函数理论 (TDDFT) 和受限活动空间二阶扰动理论 (RASPT2).
- 对三种多替代的推拉亚和一种商用红色染料 (苏丹红G) 的研究,具有不同的分子内相互作用和-双.
主要成果:
- 内分子H键稳定了转异构体,并增加了光异构化的能量屏障,在分散蓝色染料中有效地起到了"分子锁"的作用.
- 涉及阿佐基团的基托-醇复合变化改变了激发状态的性质,并有利于生产性扭转运动而不是非生产性曲路径,促进了苏丹红色G的光异构化.
- 内分子相互作用的强度与光异构化抑制的程度直接相关.
结论:
- 分子结构的修改,如分子内H键和-双聚体,可以精确地控制亚博衍生物的光异构化效率.
- 这些发现为合理设计基于亚博的新型光开关提供了有价值的见解,这些光开关具有量身定制的兴奋状态动态和光响应行为.
相关概念视频
Photochemical Electrocyclic Reactions: Stereochemistry
1.8K
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
1.8K
Cycloaddition Reactions: MO Requirements for Photochemical Activation
2.1K
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.
2.1K
Thermal and Photochemical Electrocyclic Reactions: Overview
2.3K
Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
2.3K
Electrophilic Addition of HX to 1,3-Butadiene: Thermodynamic vs Kinetic Control
2.6K
The addition of a hydrogen halide to 1,3-butadiene gives a mixture of 1,2- and 1,4-adducts. Since more substituted alkenes are more stable, the 1,4-adduct is expected to be the major product. However, the product distribution is strongly influenced by temperature; low temperature favors the 1,2-adduct, whereas the 1,4-adduct is predominant at high temperature.
2.6K
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
2.9K
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...
2.9K
Benzene to 1,4-Cyclohexadiene: Birch Reduction Mechanism
2.2K
Birch reduction uses solvated electrons as reducing agents. The reaction converts benzene to 1,4-cyclohexadiene. The reaction proceeds by the transfer of a single electron to the ring to form a benzene radical anion. This anion is highly basic—it abstracts a proton from the alcohol to form a cyclohexadienyl radical. Another single electron transfer gives the cyclohexadienyl anion. A proton transfer from the alcohol forms 1,4-cyclohexadiene. Since this reduction occurs via radical anion...
2.2K

![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
![[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)