(IV) 复合物的氧化双态光反应,使用近红外光
Nathan R East1, Robert Naumann1, Christoph Förster1
1Department of Chemistry, Johannes Gutenberg University, Mainz, Germany.
Nature chemistry
|February 9, 2024
概括
这项研究引入了一种复合物,该复合物用低能光作为强大的光催化剂. 它有效地氧化了具有挑战性的基质,如烯和烯,克服了以前地球上丰富的催化剂的局限性.
科学领域:
- 摄影化学的使用.
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 从地球上丰富的金属开发高效的光催化剂对于可持续化学至关重要.
- 现有的光催化剂通常需要高能光,并遭受能量消耗,限制其氧化能力.
研究的目的:
- 开发一种基于地球上丰富的的新型光催化剂,用于高效的光氧化.
- 为了利用低能量的光用于光催化,最大限度地减少能量损失.
- 为了使具有挑战性的基质如亚烯和的氧化.
主要方法:
- [Mn(dgpy) ]4+复合物的合成和表征.
- 通过低能近红外光激发复合体.
- 研究激发状态属性 (发光,寿命) 和氧化还原潜力.
- 测试各种基质的光氧化能力,包括纳夫他林,烯和.
主要成果:
- 在近红外光激发时,[Mn(dgpy) 2 4+复合体形成了发光双重联体到金属电荷转移 (2LMCT) 兴奋状态.
- 这种2LMCT状态的寿命为1.6ns,并且氧化纳.
- 一个高能四重奏4LMCT兴奋状态使具有高氧化潜力 (高达2.4V) 的基质的光还原成为可能,促进了亚烯和的氧化.
结论:
- 开发的复合物高效地利用低能光进行光氧化.
- 这种光催化剂克服了能耗问题,充分利用了光氧化功率.
- 它使用地球上丰富的元素和可见光来氧化具有挑战性的基质,为可持续的化学转化铺平了道路.
相关概念视频
01:21Radical Oxidation of Allylic and Benzylic Alcohols
2.0K
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...
2.0K
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
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
01:17Oxidation of Phenols to Quinones
3.0K
In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
3.0K
01:26Redox Titration: Other Oxidizing and Reducing Agents
288
Besides iodine, other oxidizing or reducing agents can serve as titrants in redox titrations. Common oxidizing titrants include KMnO4, cerium(IV), and K2Cr2O7. The choice of oxidizing titrants depends on factors like stability, cost, analyte strength, and reaction rate between the analyte and titrant. KMnO4 is a strong oxidizing titrant that reduces from Mn(VII) to Mn(II) in a highly acidic solution, simultaneously oxidizing the analyte to a higher oxidation state. In this case, KMnO4 acts as a...
288
01:12Cycloaddition Reactions: MO Requirements for Photochemical Activation
2.1K
Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
2.1K