布伦斯特德光基可以作为易斯光基吗?
Matthew J Voegtle1, Jahan M Dawlaty1
1Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States.
Journal of the American Chemical Society
|April 27, 2022
概括
研究人员使用像素这样的光基来证明光控制的易斯酸相互作用. 激发这些分子驱动易斯酸的转移,如三化物,提供新的光催化可能.
科学领域:
- 摄影化学
- 易斯酸化学
- 光催化
背景情况:
- 基因结合和易斯酸相互作用是催化和表面化学的基础.
- 光诱导的质子转移 (激发状态的Bronsted酸度/度) 是一个已久的现象.
- 控制与光的易斯酸相互作用仍然是一个未经探索的领域.
研究的目的:
- 调查光控制的易斯酸相互作用.
- 展示一个易斯酸转移到一个光激发分子.
- 探索超出质子转移应用的光基的潜力.
主要方法:
- 使用三化物 (BF3) 作为易斯酸和氨酸作为光活性易斯基.
- 构建了一个实验性的福斯特循环来量化易斯酸转移的驱动力.
- 使用时间依赖密度函数理论 (TDDFT) 和能量分解分析进行计算验证.
主要成果:
- 证明了BF3转移到光激发素的显著热力学驱动 (0. 2- 0. 7 eV).
- 这种驱动的规模与已知的布伦斯特德光基效应相当.
- 计算分析显示,该效应的起源与替代效应相关,类似于布伦斯特德光活性.
结论:
- 光激发的易斯基可以促进易斯酸转移,类似于激发状态的质子转移.
- 光基提供了一种超出质子转移的新机制来控制化学现象.
- 这项研究为光催化和光控制化学反应开辟了新的途径.
相关概念视频
Lewis Acids and Bases
45.1K
In 1923, G. N. Lewis proposed a generalized definition of acid-base behavior in which acids and bases are identified by their ability to accept or to donate a pair of electrons and form a coordinate covalent bond.
A coordinate covalent bond (or dative bond) occurs when one of the atoms in the bond provides both bonding electrons. For example, a coordinate covalent bond occurs when a water molecule combines with a hydrogen ion to form a hydronium ion. A coordinate covalent bond also results when...
A coordinate covalent bond (or dative bond) occurs when one of the atoms in the bond provides both bonding electrons. For example, a coordinate covalent bond occurs when a water molecule combines with a hydrogen ion to form a hydronium ion. A coordinate covalent bond also results when...
45.1K
Bronsted-Lowry Acids and Bases
95.1K
The acid-base reaction class has been studied for quite some time. In 1680, Robert Boyle reported traits of acid solutions that included their ability to dissolve many substances, to change the colors of certain natural dyes, and to lose these traits after coming in contact with alkali (base) solutions. In the eighteenth century, it was recognized that acids have a sour taste, react with limestone to liberate a gaseous substance (now known to be CO2), and interact with alkalis to form neutral...
95.1K
Brønsted-Lowry Acids and Bases
20.7K
In 1923, the Brønsted–Lowry definition of acids and bases was proposed by Johannes Brønsted and Thomas Lowry. According to this theory, a Brønsted acid is defined as a species that donates a proton in a chemical reaction and gets converted to its conjugate base. A Brønsted base is defined as a species that accepts a proton in a chemical reaction and gets converted into its conjugate acid. These transfers of protons are caused by the displacement of electrons in these reactions, which is...
20.7K
The Z-Scheme of Electron Transport in Photosynthesis
10.6K
The light reactions of photosynthesis assume a linear flow of electrons from water to NADP+. During this process, light energy drives the splitting of water molecules to produce oxygen. However, oxidation of water molecules is a thermodynamically unfavorable reaction and requires a strong oxidizing agent. This is accomplished by the first product of light reactions: oxidized P680 (or P680+), the most powerful oxidizing agent known in biology. The oxidized P680 that acquires an electron from the...
10.6K
Photochemical Electrocyclic Reactions: Stereochemistry
1.9K
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
1.9K
The Photochemical Reaction Center
4.3K
Reaction centers are pigment-protein complexes that initiate energy conversion from photons to chemical entities. Therefore, photochemical reaction center is a more appropriate term that describes these complexes. The Nobel laureates Robert Emerson and William Arnold provided the first experimental evidence of photochemical reaction centers by demonstrating the participation of nearly 2,500 chlorophyll molecules for the release of just one molecule of oxygen. Despite thousands of photosynthetic...
4.3K

![[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)
