在高旋铁中实现核友反应性 (II) Imido复合体:从基本步骤到合作催化
1Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States.
Accounts of chemical research
|November 13, 2023
概括
这项研究引入了一种具有增强核友性的新型高旋铁(II) imido复合体,使化和ene型转换等新催化反应成为可能.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 合成化学 合成化学
背景情况:
- 过渡金属模态复合物 (MNR) 是含化合物合成中的关键中间体.
- 伊米多连接体的特性通常因金属中心而异 (早期的核友性,晚期TM的电友性).
- 支持性联体可以显著影响 imido 联体的反应性,使其具有不寻常的特性.
研究的目的:
- 为了合成和表征一种新型的,高度核友的铁 (II) imido复合体.
- 探索这个复合物的反应性,特别是金属对象的影响.
- 为了证明这种独特的铁像素复合体所能实现的新催化转化.
主要方法:
- 铁 (III) 和铁 (II) 像素复合物的合成和表征.
- 固体测量反应性研究包括质子化,化和 [2 + 2] 反应.
- 电子结构计算以了解粘合和反应性.
- 针对化,基因/亚基二化和基转换的催化研究.
主要成果:
- 一系列与金属 (Li+,Na+,K+) 协调的高旋转Fe(II) imido复合体被合成和特征化.
- 发现金属离子适度极化FeN键,增加imido连接体的基本性.
- 异对像质子化和 [2 + 2] 循环添加等静态度反应的反应性有显著影响.
- 开发了新的催化反应,包括碳二胺的轻微 guanylation 和与基,基和基类似的反应.
结论:
- 开发出来的铁II) imido复合体表现出前所未有的核友性和反应性.
- 金属对象在调整 imido 配体的特性和指导反应结果方面发挥着至关重要的作用.
- 这项工作扩大了过渡金属模态复合物的催化应用,超出了传统的烯转移化学范围.
更多相关视频
相关概念视频
03:02Colors and Magnetism
11.7K
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...
11.7K
02:42Valence Bond Theory
8.6K
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...
8.6K
02:34Structural Isomerism
19.2K
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
19.2K
01:11ortho–para-Directing Activators: –CH3, –OH, –NH2, –OCH3
6.1K
All ortho–para directors, excluding halogens, are activating groups. These groups donate electrons to the ring, making the ring carbons electron-rich. Consequently, the reactivity of the aromatic ring towards electrophilic substitution increases. For instance, the nitration of anisole is about 10,000 times faster than the nitration of benzene. The electron-donating effect of the methoxy group in anisole activates the ortho and para positions on the ring and stabilizes the corresponding...
6.1K
01:33Radical Reactivity: Intramolecular vs Intermolecular
1.7K
Radical reactions can occur either intermolecularly or intramolecularly. In an intermolecular radical reaction, a nucleophilic radical adds to an electrophilic alkene or vice versa. In such reactions, the radical and generally the alkene, which is also called the radical trap, are two different molecules. Additionally, for such intermolecular reactions to occur, the radical trap must be active, present in an excess concentration, and the radical starting material must have a weak...
1.7K
01:23Aldehydes and Ketones with Amines: Imine Formation Mechanism
5.6K
Imine formation involves the addition of carbonyl compounds to a primary amine. It begins with the generation of carbinolamine through a series of steps involving an initial nucleophilic attack and then several proton transfer reactions. The second part includes the elimination of water, as a leaving group, to give the imine.
Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
If the pH is low or the solution is too acidic, the reaction slows down in the...
Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
If the pH is low or the solution is too acidic, the reaction slows down in the...
5.6K