当前位置: X-MOL 学术Phys. Chem. Chem. Phys. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
The mechanism of organic radical oxidation catalysed by gold nanoparticles
Physical Chemistry Chemical Physics ( IF 2.9 ) Pub Date : 2021-11-08 , DOI: 10.1039/d1cp03875c
Viacheslav Shcherbakov 1 , Sergey A Denisov 1 , Mehran Mostafavi 1
Affiliation  

Metal nanoparticles can catalyze reactions involving organic free radicals. From the first studies focused on the catalytic reduction of water by free radicals until today, the catalytic oxidation of organic radicals has not received attention. In this work, we present the results on the catalytic activity of gold nanoparticles in the oxidation of 2-propanol to acetone and acetanilide hydroxylation during water radiolysis. A detailed reaction mechanism of α-hydroxyisopropyl radical oxidation is discussed, explaining the increase in acetone formation by ca. 340% in the presence of gold nanoparticles. In the case of acetanilide hydroxylation in the presence of nanoparticles, a strong effect of oxygen in the reaction mechanism was observed: the increase in the oxygen concentration from 0 to 1.22 mM leads to a 40-fold decrease in hydroxylation product formation. This observation is unexpected since, in the absence of gold nanoparticles, oxygen stimulates hydroxylation reactions. We propose that in the presence of both oxygen and nanoparticles, oxygen attaches first to acetanilide OH-adducts, and then nanoparticles catalyze the oxidation of peroxyl type radicals, which does not lead to the formation of hydroxylation products.

中文翻译:

金纳米粒子催化有机自由基氧化的机理

金属纳米粒子可以催化涉及有机自由基的反应。从最初的研究集中在自由基催化还原水,直到今天,有机自由基的催化氧化一直没有受到关注。在这项工作中,我们展示了金纳米颗粒在水辐解过程中将 2-丙醇氧化成丙酮和乙酰苯胺羟基化的催化活性的结果。讨论了 α-羟基异丙基自由基氧化的详细反应机理,解释了丙酮形成的增加约。340% 在金纳米粒子的存在下。在纳米粒子存在下乙酰苯胺羟基化的情况下,观察到氧气对反应机制的强烈影响:氧气浓度从 0 增加到 1.22 mM 导致羟基化产物形成减少 40 倍。这一观察结果是出乎意料的,因为在没有金纳米粒子的情况下,氧气会刺激羟基化反应。我们提出,在氧和纳米颗粒同时存在的情况下,氧首先附着在乙酰苯胺 OH 加合物上,然后纳米颗粒催化过氧类自由基的氧化,这不会导致羟基化产物的形成。
更新日期:2021-11-22
down
wechat
bug