黄金催化合成的芳香化合物从aniline和酸芳香化合物
Abdessamad Grirrane1, Avelino Corma, Hermenegildo García
1Instituto de Tecnología Química, Consejo Superior de Investigaciones (CSIC), Universidad Politécnica de Valencia, 46022-Valencia, Spain.
概括
黄金纳米颗粒催化了从阿尼林和酸芳香物中有效合成芳化合物. 这种绿色化学方法避免了苛刻的试剂,在温和的条件下提供高产量.
科学领域:
- 催化剂是一种催化剂.
- 绿色化学 绿色化学
- 材料科学 材料科学 材料科学
背景情况:
- 传统的芳化合物合成通常依赖于静态测量,对环境有害的试剂,如过渡金属或酸盐.
- 开发可持续和高效的催化方法来合成化合物对于工业应用至关重要.
研究的目的:
- 开发一种用于选择性形成芳香化合物的新型催化系统.
- 探索金纳米颗粒在金属氧化物支上用于有氧氧化和还原性合反应的使用.
主要方法:
- 使用在二氧化 (TiO2) 和纳米颗粒二氧化 (CeO2) 上支的金纳米颗粒.
- 研究芳香性素氧化成化合物的有氧氧化.
- 检查一种两步,一的氧化和化合物的降解合,在TiO2上使用黄金.
主要成果:
- 在芳性化合物中,通过对素的有氧氧化实现了超过98%的产量.
- 在温和反应条件下被证明具有很高的催化效率.
- 成功合成了对称和不对称的芳香化合物,展示了该方法的多功能性.
结论:
- 在TiO2和CeO2上的金纳米粒子为芳香化合物合成提供了高效和环保的催化途径.
- 开发的催化系统为传统方法提供了可持续的替代方案,具有工业扩展的潜力.
- 这种方法可以从易于获得的前体,如阿尼林和酸芳等中化合物的直接合成.
相关概念视频
Preparation of 1° Amines: Azide Synthesis
Direct alkylation of ammonia produces polyalkylated amines, along with a quaternary ammonium salt. To exclusively prepare primary amines, the azide synthesis method can be used.
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
Preparation of Amines: Reduction of Oximes and Nitro Compounds
Oximes can be reduced to primary amines using catalytic hydrogenation, hydride reduction, or sodium metal reduction. The reduction of aliphatic and aromatic nitro compounds to primary amines takes place by either catalytic hydrogenation or by using active metals like Fe, Zn, and Sn in the presence of an acid.
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
Preparation of 1° Amines: Gabriel Synthesis
Direct alkylation is not a suitable method for synthesizing amines because it produces polyalkylated products. Gabriel synthesis is the most preferred method to exclusively make primary amines. The method uses phthalimide, which contains a protected form of nitrogen that participates in alkylation only once to predominantly give primary amines.
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
Treating arylamines with nitrous acid gives aryldiazonium salts that are effective substrates in nucleophilic aromatic substitution reactions. The diazonio group in these salts can be easily displaced by different nucleophiles, yielding a wide variety of substituted benzenes. The leaving group departs as nitrogen gas, and this easy elimination is the driving force for the substitution reaction.
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.


