![[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)
在Cu (I) - 复合物中揭示反氧非无害的结
Evan J Gardner1, Sean C Marguet2, Caitlyn R Cobb1
1Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States.
Journal of the American Chemical Society
|September 21, 2021
概括
这项研究探讨了铜复合体中的分子内H键,以稳定氨合成的中间体. 结促进了双原子的转移,为固定提供了新的途径.
科学领域:
- 无机化学
- 有机金属化学
- 催化剂
背景情况:
- 由于 (N2H2) 等高能中间体,将 (N2) 减少为氨 (NH3) 是至关重要的,但在动力学上具有挑战性.
- 作为稳定这些反应性中间体的策略,研究了分子内结合 (H-结合).
研究的目的:
- 探索分子内H键在铜复合体内稳定二中间体中的作用.
- 调查H结合对固定反应途径的影响.
主要方法:
- [TpCu]2 ((μ-N2H2) 复合物的合成和X射线结晶学与悬挂的芳香N-异环 (xHet).
- 红外 (IR) 光谱和低温1H NMR研究以描述H键和动态平衡.
- 用密度函数理论 (DFT) 计算分析电子结构和反应路径.
- 共振拉曼光谱用于研究N-N键的振动变化.
主要成果:
- 在[pyMeTpCu]2[μ-N2H2]中证实了悬挂N-异环和桥接N2H2连接体之间的H键.
- DFT和NMR研究显示了对称的H键基因之间的动态平衡.
- 响应拉曼研究显示,由于H键的作用,NN键振动发生了显著的变化.
- DFT计算表明,协同的双原子转移 (HAT) 从N2H2到xHet是一个热力学上有利的途径.
结论:
- 在[TpCu]2[μ-N2H2]复合体中的分子内H键有效地稳定了二中间体.
- 反氧非无害的H结合可以促进N2H2的部分H原子转移.
- 金属辅助协同双HAT为N2/N2H2相互转换提供了可行的途径,与固定催化有关.
更多相关视频
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
9.4K
06:53Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
2.2K
相关概念视频
03:02Colors and Magnetism
12.5K
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...
12.5K
02:58Crystal Field Theory - Octahedral Complexes
28.4K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
28.4K
01:20Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
2.1K
Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...
2.1K
03:45Formation of Complex Ions
24.5K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
24.5K
02:42Valence Bond Theory
9.8K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
9.8K
01:10Aldehydes and Ketones with HCN: Cyanohydrin Formation Mechanism
3.7K
Cyanohydrins are formed when cyanide nucleophiles and carbonyl compounds like aldehydes and ketones react. A strong base, the cyanide ion, catalyzes cyanohydrin formation. The ions are generated from HCN under aqueous conditions. Once the cyanide ions are generated, the first step involves the nucleophilic attack of the cyanide ions on the electrophilic carbonyl carbon. This attack shifts the π electrons from the C=O to the oxygen atom forming the alkoxide ion intermediate. The alkoxide anion...
3.7K