![[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)
一个μ-1,2-Peroxo和一个μ-1,1-Hydroperoxo双铜的质子诱导,可逆的相互转换 (II) 复杂的复合
Nicole Kindermann1, Sebastian Dechert1, Serhiy Demeshko1
1Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammannstraße 4, 37077 Göttingen, Germany.
Journal of the American Chemical Society
|June 11, 2015
概括
双铜 (II) 氧复合物的质子化产生一个稳定的氧复合物. 这种复合体以X射线衍射为特征,可以调解氧转移反应,但不能调解原子抽象.
科学领域:
- 无机化学 无机化学
- 协调化学 协调化学
- 生物有机化学 生物有机化学
背景情况:
- 双铜 (II) 复合物与氧联结物是各种氧化反应中的关键中间体.
- 了解这些复合物的反应性和稳定性是模仿生物系统的关键.
- 质子化状态显著影响金属氧物种的电子和结构性质.
研究的目的:
- 为了研究μ-1,2-peroxo双铜 (II) 复合物的质子化.
- 为了表征得到的μ-1,1-hydroperoxo双铜 (II) 复合物.
- 为了确定氧复合物的氧化反应中的反应性.
主要方法:
- 合成和表征一个μ-1,2-peroxo双铜 (II) 复合物使用基于pyrazolate的配体.
- 质子和脱质子研究以确定Cu2OOH单元的pKa.
- 用X射线衍射测定水氧复合物的结构.
- 光谱分析 (IR) 来研究O-O键的振动.
- 使用PPh3作为基质的反应性研究.
主要成果:
- 对μ-1,2-氧二铜(II) 复合物 (2) 的质子化产生一个稳定的μ-1,1-氧二铜(II) 复合物 (3).
- 在Cu2OOH单位的pKa被确定为22.2±0.3在乙尼中.
- 综合体3表现出前所未有的稳定性 (t(1/2) = 9 h),并且具有结构性特征.
- O-O 键的长度保持相似,但O-O 拉伸频率在复杂 3 中显著增加.
- 复合物3调解2e(-) 氧转移到PPh3,但对H原子抽象没有反应.
结论:
- 该研究表明二铜氧复合物的可逆质子化/脱质子化,高的pKa表明稳定的水氧物种.
- 结构和光谱数据显示在质子化后发生了微妙但显著的变化.
- 水氧二铜 (II) 复合物是氧转移反应的有效调解剂,突出了其在催化中的潜力.
更多相关视频
05:51Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
6.8K
11:04Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
Published on: September 7, 2019
10.0K
相关概念视频
02:04Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
8.2K
Diols are compounds with two hydroxyl groups. In addition to syn dihydroxylation, diols can also be synthesized through the process of anti dihydroxylation. The process involves treating an alkene with a peroxycarboxylic acid to form an epoxide. Epoxides are highly strained three-membered rings with oxygen and two carbons occupying the corners of an equilateral triangle. This step is followed by ring-opening of the epoxide in the presence of an aqueous acid to give a trans diol.
8.2K
01:34Woodward–Hoffmann Selection Rules and Microscopic Reversibility
4.2K
Electrocyclic reactions, cycloadditions, and sigmatropic rearrangements are concerted pericyclic reactions that proceed via a cyclic transition state. These reactions are stereospecific and regioselective. The stereochemistry of the products depends on the symmetry characteristics of the interacting orbitals and the reaction conditions. Accordingly, pericyclic reactions are classified as either symmetry-allowed or symmetry-forbidden. Woodward and Hoffmann presented the selection criteria for...
4.2K
03:02Colors and Magnetism
14.7K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
14.7K
01:17Oxidation of Phenols to Quinones
5.3K
In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
5.3K
02:21Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate
18.5K
Alkenes can be dihydroxylated using potassium permanganate. The method encompasses the reaction of an alkene with a cold, dilute solution of potassium permanganate under basic conditions to form a cis-diol along with a brown precipitate of manganese dioxide.
18.5K
01:26Photochemical 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