由光驱动的,由质子控制的,催化性有氧C-H氧化,由一个Mn(III) 氨酸化合物复合物介导
Heather M Neu1, Jieun Jung2, Regina A Baglia1
1†Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States.
Journal of the American Chemical Society
|April 4, 2015
概括
这项研究表明,复合物可以利用可见光催化基C-H键的有氧氧化. 在特定位置的质子化对于催化活性至关重要,而双质子化则会停止反应性.
科学领域:
- 无机化学 无机化学
- 催化剂是一种催化剂.
- 有机合成 有机合成
背景情况:
- 可见光驱动的催化提供了一种可持续的化学转换方法.
- 基C-H键的氧化是有机合成中的一个基本反应.
- 复合物在氧化反应中被探索其催化潜力.
研究的目的:
- 通过使用Mn(III) 科罗拉复合物,研究基C-H键的可见光驱动的催化有氧氧化.
- 阐明质子化在催化循环中的作用和催化剂稳定性.
- 为了描述催化剂的静止状态和反应中间体.
主要方法:
- 通过X射线衍射来确定静止催化剂的晶体结构.
- 谱学方法 (例如,UV-Vis,NMR) 来研究催化剂的电子特性和中间体.
- 在可见光照射下进行有氧氧化反应,以评估催化活性.
主要成果:
- 催化剂,一个Mn(III) 冠氨酸复合物,成功调解了基C-H键的可见光驱动的有氧氧化.
- 催化周转需要在连接体上单个远端位点进行选择性质子,形成[Mn(III) ((H2O) ((TBP8Cz ((H)))) ] ((+).
- 在两个偏远地点的质子化使催化剂与O2的反应性失活,而Mn{\displaystyle V}{\displaystyle O}中间体显示了温度依赖的价值分离.
结论:
- 在有氧氧化过程中,选择性质子对Mn(III) 科罗拉复合物的催化活性至关重要.
- 了解质子化状态和中间体是设计高效氧化催化剂的关键.
- 这项工作提供了关于由复合物催化光驱动的C-H键氧化机制的见解.
相关概念视频
Electron Transport Chain: Complex III and IV
9.9K
During the electron transport chain, electrons from NADH and FADH2 are first transferred to complexes I and II, respectively. These two complexes then transfer the electrons to ubiquinol, which carries them further to complex III. Complex III passes the electrons across the intermembrane space to Cyt c, which carries them further to complex IV. Complex IV donates electrons to oxygen and reduces it to water. As electrons pass through complexes I, III, and IV, the energy released aids the pumping...
9.9K
Radical Oxidation of Allylic and Benzylic Alcohols
3.2K
Activated manganese(IV) oxide can selectively oxidize allylic and benzylic alcohols via a radical intermediate mechanism. Primary allylic alcohols are oxidized to aldehydes, while secondary allylic alcohols yield ketones. The redox reaction of potassium permanganate with an Mn(II) salt such as manganese sulfate (under either alkaline or acidic conditions), followed by thorough drying, yields the oxidizing agent: activated MnO2. While MnO2 is insoluble in the solvents used for the reaction, the...
3.2K
Electron Transport Chains
118.1K
The final stage of cellular respiration is oxidative phosphorylation that consists of two steps: the electron transport chain and chemiosmosis. The electron transport chain is a set of proteins found in the inner mitochondrial membrane in eukaryotic cells. Its primary function is to establish a proton gradient that can be used during chemiosmosis to produce ATP and generate electron carriers, such as NAD+ and FAD, that are used in glycolysis and the citric acid cycle.
The ETC is comprised of...
The ETC is comprised of...
118.1K
Oxygenic Photosynthesis
1.0K
Oxygenic photosynthesis is a fundamental process in which light energy is harnessed to drive the oxidation of water, leading to the production of molecular oxygen (O₂), adenosine triphosphate (ATP), and nicotinamide adenine dinucleotide phosphate (NADPH). This process is essential for sustaining aerobic life on Earth and is primarily carried out by cyanobacteria, algae, and plants. The core of oxygenic photosynthesis lies in the thylakoid membranes, where chlorophyll pigments facilitate...
1.0K
Anoxygenic Photosynthesis
1.8K
Anoxygenic photosynthesis is a phototrophic process that captures light energy to drive carbon fixation without producing molecular oxygen. Unlike oxygenic photosynthesis, which utilizes water as an electron donor and releases oxygen, anoxygenic phototrophs use alternative electron donors such as hydrogen sulfide (H₂S), elemental sulfur (S⁰), or thiosulfate (S₂O₃²⁻). This process is carried out by diverse groups of bacteria, including purple bacteria, green...
1.8K
Chemiosmosis
118.7K
Oxidative phosphorylation is a highly efficient process that generates large amounts of adenosine triphosphate (ATP), the basic unit of energy that drives many cellular processes. Oxidative phosphorylation involves two processes— the electron transport chain and chemiosmosis.
Electron Transport Chain
The electron transport chain involves a series of protein complexes on the inner mitochondrial membrane that undergo a series of redox reactions. At the end of this chain, the electrons...
Electron Transport Chain
The electron transport chain involves a series of protein complexes on the inner mitochondrial membrane that undergo a series of redox reactions. At the end of this chain, the electrons...
118.7K


