一种阿克里丁基 photoreductant 的发现和表征
Ian A MacKenzie1, Leifeng Wang1, Nicholas P R Onuska1
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Nature
|April 3, 2020
概括
研究人员发现了一种强大的中性基, 这一发现为以前需要强烈的还原剂的有机转化开辟了新的道路.
科学领域:
- 有机化学
- 摄影化学
- 催化剂
背景情况:
- 光诱导电子转移 (PET) 在吸收光后驱动电子转移反应.
- 在光合作用,光伏和光敏感材料中,
- 氧催化利用PET产生有机自由基,从而实现新的化学转化.
研究的目的:
- 发现,描述和探索新型中性有机激素作为光催化剂的反应性.
- 研究中性有机基在兴奋状态电子转移反应中的潜力.
- 通过这种强大的激素催化剂来证明新的合成应用.
主要方法:
- 进行光谱分析以描述激进物种.
- 计算研究以了解电子结构和激发状态.
- 化学反应性研究,以评估其在有机转化中的催化性能.
主要成果:
- 发现和描述一个具有高度负激发状态氧化潜力的中性基 (-3.36V与SCE).
- 确定一个曲的分子内电荷转移物种, 负责填充强大的高能双倍激发状态.
- 证明激素具有催化反应的能力,通常需要金属或溶解金属减少剂.
结论:
- 一个中性阿克里丁基作为一个非常强大的光反氧化催化剂.
- 独特的电子结构促进了强大的光减光能力.
- 这种催化剂使得以前因需要强烈的还原剂而受到限制的高效有机转化成为可能.
相关概念视频
Radical Formation: Addition
2.1K
Radicals can be formed by adding a radical to a spin-paired molecule. This is typically observed with unsaturated species, where the addition of a radical across the π bond leads to the production of a new radical by dissolving the π bond. For example, the addition of a Br radical to an alkene yields a carbon-centered radical.
Similar to charge conservation in chemical reactions, spin conservation is implicit for radical reactions. Accordingly, the product formed must possess an...
Similar to charge conservation in chemical reactions, spin conservation is implicit for radical reactions. Accordingly, the product formed must possess an...
2.1K
Radical Reactivity: Overview
2.6K
Radicals, the highly reactive species, gain stability by undergoing three different reactions. The first reaction involves a radical-radical coupling, in which a radical combines with another radical, forming a spin‐paired molecule. The second reaction is between a radical and a spin‐paired molecule, generating a new radical and a new spin‐paired molecule. The third reaction is radical decomposition in a unimolecular reaction, forming a new radical and a spin‐paired...
2.6K
Radical Formation: Elimination
2.1K
Another method of radical formation is the elimination process. It is the opposite of the addition route and is driven by the instability of the radical. For example, as depicted in Figure 1, dibenzoyl peroxide yields a pair of unstable radicals upon homolysis. Given its instability, this radical spontaneously undergoes elimination via a C–C bond cleavage to form a relatively more stable phenyl radical. The mechanism involves cleavage of the bond between the α and β positions with respect...
2.1K
Radical Reactivity: Nucleophilic Radicals
2.6K
Radicals adjacent to electron-donating groups are called nucleophilic radicals. These radicals readily react with electrophilic alkenes. The SOMO–LUMO interactions are the driving force for the reaction, where the high-energy SOMO of the electron-rich, nucleophilic radicals interacts with the low-energy LUMO of the electron-deficient, electrophilic alkenes. Such SOMO–LUMO interactions are the basis of reactive radical traps, affecting the selectivity in radical reactions. For...
2.6K
Preparation of Amines: Reductive Amination of Aldehydes and Ketones
3.6K
Carbonyl compounds and primary amines undergo reductive amination first to produce imines, followed by secondary amines in the same reaction mixture, using selective reducing agents like sodium cyanoborohydride or sodium triacetoxyborohydride. Reductive amination produces different degrees of substitution of amines depending on the starting amine substrate.
3.6K
Radical Formation: Overview
2.5K
A bond can be broken either by heterolytic bond cleavage to form ions or homolytic bond cleavage to yield radicals. A fishhook arrow is used to represent the motion of a single electron in homolytic bond cleavage. There are two main sources from which radicals can be formed:
Radicals from spin-paired molecules:
Radicals can be obtained from spin-paired molecules either by homolysis or electron transfer. While two radicals are formed in the former, an electron is added in the...
Radicals from spin-paired molecules:
Radicals can be obtained from spin-paired molecules either by homolysis or electron transfer. While two radicals are formed in the former, an electron is added in the...
2.5K
![[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)

