フェノラートアニオンの光酸化は,水/空気界面で加速される
Caleb J C Jordan1, Eleanor A Lowe1, Jan R R Verlet1
1Department of Chemistry, Durham University, Durham, DH1 3LE, United Kingdom.
Journal of the American Chemical Society
|July 28, 2022
まとめ
フェノラートアニオンの場合,水/空気界面での分子光力学はより速い. 表面のダイナミクスは 大量の水とは異なり 独特の腐敗経路を示し フェノルの行動と大きく対照的です
科学分野:
- 物理化学
- 表面科学
- 写真化学
背景:
- 分子の光力学は インターフェースで大きく変化します
- インターフェイス反応を検知することは困難で,しばしば振動総周波数生成 (SFG) のような間接的な方法に依存します.
研究 の 目的:
- 水/空気界面でのフェノラートアニオンの光産物形成を直接探知する.
- 表面フェノラートダイナミクスを散布水と比較し,フェノルの行動と対比する.
主な方法:
- インターフェイスフェノラートの研究のための時間解像度電子SFGスペクトロスコーピー
- 散布水フェノラートダイナミクスを分析するための一時的吸収スペクトロスコーピー.
- 表面と大量光力学の比較
主要な成果:
- フェノラート光産物形成は,水/空気界面で,散布水と比較して2〜4倍速い.
- 表面で観察された追加の崩壊プロセスは,水素化された電子拡散または強化されたゲミナット再結合を含む可能性があります.
- フェノールは,かなり速いダイナミクス (10^4倍) を表し,フェノラートとは異なり,水素化された電子を生成します.
結論:
- インターフェイス分子光力学は,大量行動と有意に異なる.
- 電子SFGによる直接的な探査は,表面特異的な反応経路を明らかにします.
- フェノラートアニオンの界面光化学はフェノールとは異なる.
さらに関連する動画
関連する概念動画
01:17Oxidation of Phenols to Quinones
3.4K
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...
3.4K
01:20Radical Autoxidation
2.2K
The oxidation of an organic compound in the presence of air or oxygen is called autoxidation. For example, cumene reacts with oxygen to form hydroperoxide. Autoxidation involves initiation, propagation, and termination steps. Many organic compounds are susceptible to autoxidation—especially ethers in the presence of oxygen, which form hydroperoxides. Even though this reaction is slow, old ether bottles contain small amounts of peroxide, which leads to laboratory explosions during ether...
2.2K
02:04Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
6.1K
Diols are compounds with two hydroxyl groups. In addition to syn dihydroxylation, diols can also be synthesized through the process of anti dihydroxylation. The process involves treating an alkene with a peroxycarboxylic acid to form an epoxide. Epoxides are highly strained three-membered rings with oxygen and two carbons occupying the corners of an equilateral triangle. This step is followed by ring-opening of the epoxide in the presence of an aqueous acid to give a trans diol.
6.1K
02:50Catalysis
27.4K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
27.4K
02:36Acidity and Basicity of Alcohols and Phenols
19.8K
Like water, alcohols are weak acids and bases. This is attributed to the polarization of the O–H bond making the hydrogen partially positive. Moreover, the electron pairs on the oxygen atom of alcohol make it both basic and nucleophilic. Protonation of an alcohol converts hydroxide, a poor leaving group, into water—a good one. The two acid–base equilibria corresponding to ethanol are depicted below.
19.8K
01:46Oxidative Cleavage of Alkenes: Ozonolysis
10.9K
In ozonolysis, ozone is used to cleave a carbon–carbon double bond to form aldehydes and ketones, or carboxylic acids, depending on the work-up.
Ozone is a symmetrical bent molecule stabilized by a resonance structure.
Ozone is a symmetrical bent molecule stabilized by a resonance structure.
10.9K