受到保护但可访问:氧气激活由一个稳定卡利沙的未被破坏的黄金集群
1Department of Chemistry, Nanoscience Center, University of Jyväskylä, FI-40014 Jyväskylä, Finland.
Journal of the American Chemical Society
|August 24, 2013
概括
卡力沙林稳定黄金集群,使氧气激活用于催化. 这项研究表明,黄金集群可以在环境条件下作为高效的氧化催化剂,模仿酶活性位点.
科学领域:
- 计算化学是一种计算化学.
- 催化剂是一种催化剂.
- 纳米材料是一种纳米材料.
背景情况:
- 亚纳米金属集群是有希望的催化剂,但往往缺乏稳定性.
- 酶金属中心为设计人工催化剂提供了灵感.
研究的目的:
- 为了研究使用calixarenes稳定亚纳米金的稳定.
- 探索这些稳定黄金集群对于氧化反应的催化潜力.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 分析了calixarene宿主和Au11集群之间的相互作用.
- 研究了黄金集群上的二氧化物结合和激活.
主要成果:
- 卡利克萨伦有效地稳定了亚纳米Au11集群.
- 稳定集群允许像O2这样的小分子进入反应部位.
- 最多三种二氧化物分子可以结合并被激活到超氧状态.
- DFT计算证实了环境条件催化作用的可能性.
结论:
- 卡利沙稳定黄金集群显示出作为氧化催化剂的前景.
- 阐明了O2激活的机制.
- 这项工作为设计类似酶的黄金催化剂提供了一条途径.
相关概念视频
01:46Oxidative Cleavage of Alkenes: Ozonolysis
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.
02:44Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
02:36Oxymercuration-Reduction of Alkenes
Oxymercuration–reduction of alkenes is one of the major reactions converting alkenes to alcohols. It involves the hydration of alkenes with mercuric acetate in a mixture of tetrahydrofuran and water, forming an organomercury adduct. This is followed by a demercuration step in which the adduct is reduced to an alcohol using sodium borohydride.
02:21Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate
Alkenes can be dihydroxylated using potassium permanganate. The method encompasses the reaction of an alkene with a cold, dilute solution of potassium permanganate under basic conditions to form a cis-diol along with a brown precipitate of manganese dioxide.
03:11Oxidation-Reduction Reactions
Oxidation–Reduction Reactions
01:12Cycloaddition Reactions: MO Requirements for Photochemical Activation
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.