西米达和相关联体为Cu催化化酸盐-基因循环添加
Valentin O Rodionov1, Stanislav I Presolski, Sean Gardinier
1Department of Chemistry and The Skaggs Institute of Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
Journal of the American Chemical Society
|October 5, 2007
概括
三二二二甲基) 胺是铜I催化酸环添加的优质配体. 一种溶于水的配体, (BimC4A) 3,使得使用最小的铜催化剂能够快速,高产的合成功能化三醇.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 药用化学 医学化学
背景情况:
- 铜(I) 催化亚酸环添加 (CuAAC) 是一个重要的"点击"化学反应.
- 干设计对于优化CuAAC催化剂效率和范围至关重要.
- 三2-二二甲基) 胺为CuAAC的一种有前途的配体类别.
研究的目的:
- 评价三二二二醇甲基) 胺和相关联体作为CuAAC加速器.
- 为了研究连接体结构对催化活性的影响.
- 为了确定快速和高产的三醇合成的最佳条件.
主要方法:
- 绝对速率测量采用比率火动力学.
- 使用反应热量计进行相对速率测量.
- 合成和评估各种本齐米达,本佐提亚和化连接剂.
主要成果:
- 三{2-胺醇甲基) 胺显示了对CuAAC的优异加速.
- 在缩条件下,具有悬挂基碳酸盐臂的配体在缩条件下具有优势.
- 催化剂系统在pH值和缓冲盐方面表现出复杂的行为.
- 高的催化率甚至在高度的连接剂中也保持不变.
- (BimC4A) 3,一种水溶性联体,促进了高效的三醇合成,含量为0.01-0.5mol % Cu.
结论:
- 三二二二甲基胺是CuAAC反应的高度有效的配体.
- 溶于水的配体 (BimC4A) 3提供了一个方便而有效的途径,以功能化三醇.
- 这种催化系统适用于快速,高产率的合成与低催化剂负载.
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...
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...
Nucleophilic Aromatic Substitution: Elimination–Addition
Simple aryl halides do not react with nucleophiles. However, nucleophilic aromatic substitutions can be forced under certain conditions, such as high temperatures or strong bases. The mechanism of substitution under such conditions involves the highly unstable and reactive benzyne intermediate. Benzyne contains equivalent carbon centers at both ends of the triple bond, each of which is equally susceptible to nucleophilic attack. This 50–50 distribution of products is confirmed through isotopic...
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...
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.
Cycloaddition Reactions: MO Requirements for Thermal Activation
Thermal cycloadditions are reactions where the source of activation energy needed to initiate the reaction is provided in the form of heat. A typical example of a thermally-allowed cycloaddition is the Diels–Alder reaction, which is a [4 + 2] cycloaddition. In contrast, a [2 + 2] cycloaddition is thermally forbidden.


