通过-复合物逐步减少二,产生U (VI) /U (IV) 四化集群
Nadir Jori1, Luciano Barluzzi1, Iskander Douair2
1Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
Journal of the American Chemical Society
|July 16, 2021
概括
这项研究报告了第一个由二复合物的二 (N2) 裂变为化物的例子,形成了一个新的四核集群. 这一突破为固机制和化物化学提供了新的见解.
科学领域:
- 无机化学
- 有机金属化学
- 材料科学
背景情况:
- 假设多金属合作性对于二 (N2) 裂变为化物 (N3) 是至关重要的.
- 由于没有分离的中间体,N2裂变的确切机制尚不清楚.
研究的目的:
- 通过复合物的N2裂变机制的研究.
- 合成和描述由N2裂变产生的新型化物集群.
- 探索由此产生的化物种的反应性.
主要方法:
- 使用KC8进行二复合物的降解.
- 四核四化集群的隔离和结构特征 [K6{(OSi(OtBu) 3) 2UIV} 3{(OSi(OtBu) 3) 2UVI}
- 实验和计算研究以阐明反应机制,包括电子转移和结合效应.
主要成果:
- 通过二复合物的N2裂变成功合成了一种新型四核四化集群 (1).
- 复合体1的结构具有一个独特的中心与四个化物和一个跨NUVIN的核心.
- 机理学研究发现了连续的单电子转移和合作结合,促进N2裂变形成二二化物 (X).
- 核化物很容易与质子反应形成氨 (产量为93-97%),并与13CO反应产生K13CN和KN13CO.
结论:
- 这项工作提供了第一个由二复合物介导的二裂变的例子,产生了独特的四核集群.
- 这项研究阐明了N2裂变中的顺序电子转移和辅助机制.
- 合成的化物集群表现出多功能反应性,使氨和化合物的形成成为可能.
相关概念视频
Nuclear Transmutation
19.6K
Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus, or the reaction of a nucleus with another particle. The first manmade nucleus was produced in Ernest Rutherford’s laboratory in 1919 by a transmutation reaction, the bombardment of one type of nuclei with other nuclei or with neutrons. Rutherford bombarded nitrogen-14 atoms with high-speed α particles from a natural radioactive isotope of radium and observed...
19.6K
Rate-Determining Steps
34.2K
Relating Reaction Mechanisms
In a multistep reaction mechanism, one of the elementary steps progresses significantly slower than the others. This slowest step is called the rate-limiting step (or rate-determining step). A reaction cannot proceed faster than its slowest step, and hence, the rate-determining step limits the overall reaction rate.
The concept of rate-determining step can be understood from the analogy of a 4-lane freeway with a short-stretch of traffic-bottleneck caused due to...
In a multistep reaction mechanism, one of the elementary steps progresses significantly slower than the others. This slowest step is called the rate-limiting step (or rate-determining step). A reaction cannot proceed faster than its slowest step, and hence, the rate-determining step limits the overall reaction rate.
The concept of rate-determining step can be understood from the analogy of a 4-lane freeway with a short-stretch of traffic-bottleneck caused due to...
34.2K
Ladder Diagrams: Complexation Equilibria
464
Ladder diagrams are useful for evaluating equilibria involving metal-ligand complexes. The vertical scale of the ladder diagram represents the concentration of unreacted or free ligand, pL. The horizontal lines on the scale depict the log of stepwise formation constants for metal-ligand complexes and indicate the dominant species in all the regions.
The formation constant, K1, for the formation of Cd(NH3)2+ complex from cadmium and ammonia is 3.55 × 102. Log K1 (i.e. pNH3) is 2.55, and...
The formation constant, K1, for the formation of Cd(NH3)2+ complex from cadmium and ammonia is 3.55 × 102. Log K1 (i.e. pNH3) is 2.55, and...
464
Nitriles to Amines: LiAlH4 Reduction
4.0K
Nitriles are reduced to amines in the presence of strong reducing agents like lithium aluminum hydride through a typical nucleophilic acyl substitution. The reaction requires two equivalents of the reducing agent. The reducing agent acts as a source of hydride ions.
As shown below, the mechanism involves three steps. Firstly, the hydride ion acting as a nucleophile attacks the nitrile carbon to form an anion. In the second step, a second equivalent of the hydride ion attacks the anion to...
As shown below, the mechanism involves three steps. Firstly, the hydride ion acting as a nucleophile attacks the nitrile carbon to form an anion. In the second step, a second equivalent of the hydride ion attacks the anion to...
4.0K
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
4.2K
Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.
4.2K
Valence Bond Theory
9.9K
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...
9.9K


