"π-Hole-π"相互作用通过内部球电子转移促进光催化化
Jingzhi Lu1, Navneet S Khetrapal1, Jacob A Johnson1
1Department of Chemistry, University of Nebraska-Lincoln , Lincoln, Nebraska 68588, United States.
Journal of the American Chemical Society
|December 15, 2016
概括
我们开发了一种无金属的光催化方法, 这一过程利用特定的相互作用和固态因子来控制反应速率和电子转移机制.
科学领域:
- 有机化学
- 光催化
- 材料科学
背景情况:
- 聚氨酸 (FA) 在各种工业应用中普遍存在,但它们的环境持久性带来了挑战.
- 开发高效和选择性的除方法对于环境修复和合成化学至关重要.
- 无金属光催化为传统方法提供了可持续的替代方案.
研究的目的:
- 引入一种新型的无金属光催化水化 (HDF) 聚烯 (FA).
- 调查基于pyrene的光催化剂 (Py) 在促进电子转移和HDF中的作用.
- 阐明硬体和电子因素对HDF反应机制和速率的影响.
主要方法:
- 使用基于pyrene的光催化剂,用于非金属的HDF.
- 分析了光催化剂和基质之间的电子相互作用 (π-孔-π).
- 研究了固体阻碍对反应动力学和电子转移途径的影响.
主要成果:
- 使用烯衍生物实现了非金属的光催化HDF.
- 证明微弱的π-孔-π相互作用促进了电子转移,尽管能量不良 (ΔGET高达0.63 eV).
- 确立了pyrene光催化剂和FA基板之间的固体阻碍决定了HDF速率,这表明了内部球的电子传递机制.
结论:
- 光催化剂和基质的尺寸和形状对于控制光催化中的电子转移机制和速率至关重要.
- 这项研究为设计高效的光催化系统提供了洞察力.
- 突出了基于的光催化剂在可持续的有机转化中的潜力.
相关概念视频
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
7.8K
Bromination and chlorination of aromatic rings by electrophilic aromatic substitution reactions are easily achieved, but fluorination and iodination are difficult to achieve. Fluorine is so reactive that its reaction with benzene is difficult to control, resulting in poor yields of monofluoroaromatic products. To address this, Selectfluor reagent is used as a fluorine source in which a fluorine atom is bonded to a positively charged nitrogen.
7.8K
Acid Halides to Carboxylic Acids: Hydrolysis
3.7K
Hydrolysis of acid halides is a nucleophilic acyl substitution reaction in which acid halides react with water to give carboxylic acids. The reaction occurs readily and does not require acid or a base catalyst.
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic...
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic...
3.7K
Radical Substitution: Hydrogenolysis of Alkyl Halides with Tributyltin Hydride
2.3K
Radical substitution reactions can be used to remove functional groups from molecules. The hydrogenolysis of alkyl halides is one such reaction, where the weak Sn–H bond in tributyltin hydride reacts with alkyl halides to form alkanes. Here, the reagent Bu3SnH yields tributyltin halide as a byproduct.
The bonds formed in this reaction are stronger than the bonds broken, making it energetically favorable. The reaction follows a radical chain mechanism similar to radical halogenation reactions,...
The bonds formed in this reaction are stronger than the bonds broken, making it energetically favorable. The reaction follows a radical chain mechanism similar to radical halogenation reactions,...
2.3K
Photochemical Electrocyclic Reactions: Stereochemistry
2.4K
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
2.4K
Radical Formation: Homolysis
4.6K
A bond is formed between two atoms by sharing two electrons. When this bond is broken by supplying sufficient energy, either two electrons can be taken up by one atom forming ions by the cleavage called heterolysis, or the two electrons are shared by two atoms, with one each creating radicals by the cleavage called homolysis.
4.6K

![[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)
