高价值非海姆Fe (IV) O/Ru (IV) O复合物催化C-H激活活性和道道:一个比较的DFT调查
Akanksha Katoch1, Debasish Mandal1
1Department of Chemistry and Biochemistry, Thapar Institute of Engineering and Technology, Patiala-147001, Punjab, India. debasish.mandal@thapar.edu.
Dalton transactions (Cambridge, England : 2003)
|January 12, 2024
概括
铁氧复合物比氧复合物具有更高的C-H激活反应性,这解释了大自然对酶中铁的偏好. 这项研究使用密度函数理论来比较这些金属氧催化剂.
科学领域:
- 有机金属化学 有机金属化学
- 计算化学的计算化学
- 生物模拟催化剂的使用
背景情况:
- 高价值的金属-氧合物复合物在生物C-H激活中至关重要.
- 铁和是金属酶中的关键金属,但它们在C-H激活中的相对反应性尚未完全理解.
- 了解这些差异可以指导模仿酶活性的合成催化剂的设计.
研究的目的:
- 使用密度函数理论,比较高价值铁氧和鲁氧复合体的C-H激活活性.
- 阐明控制反应率差异的基础电子和结构因素.
- 解释自然C-H激活酶中铁偏好于的原因.
主要方法:
- 密度函数理论 (DFT) 的计算被用来研究四个模型复合体:[Ru(IV) O(tpy-dcbpy) ],[Fe(IV) O(tpy-dcbpy) ],[Ru(IV) O(TMCS]和[Fe(IV) O(TMCS] .
- 通过使用醇,乙和二甲等基质来评估反应性.
- 分析包括旋转状态,硬度因子,扭曲能量,接受器轨道能量和量子力学道.
主要成果:
- 与它们的 (IV) -oxo对应物相比,铁 (IV) -oxo复合物显示出明显更高的C-H激活反应性.
- 具有tpy-dcbpy宏循环连接体框架的复合物表现出比具有TMCS连接体的复合物更强的反应性,不论中心金属.
- 铁(IV) -oxo复合物有利于五重奏反应状态,而(IV) -oxo复合物仅限于三重奏状态,有助于提高铁的反应性.
结论:
- 由于具有有利的电子和结构性质,铁在高价值氧化复合物中对C-H激活的反应性比更强.
- 量子力学道在两种金属的C-H激活中起作用,但不会改变观察到的反应性趋势.
- 这些发现为生物C-H激活系统中铁比的流行提供了机制基础.
更多相关视频
10:52Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics
Published on: April 12, 2019
12.8K
![Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F55858.jpg&w=3840&q=50)
10:01Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase
Published on: December 4, 2017
12.2K
相关概念视频
02:58Crystal Field Theory - Octahedral Complexes
26.5K
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...
26.5K
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
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
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
42.6K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
42.6K
03:45Formation of Complex Ions
23.6K
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...
23.6K
01:26Photochemical Electrocyclic Reactions: Stereochemistry
1.8K
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
1.8K