合理设计第二代催化剂,使用西-赫克反应制备艾利西兰
Jesse R McAtee1, Glenn P A Yap, Donald A Watson
1Department of Chemistry and Biochemistry, University of Delaware , Newark, Delaware 19716, United States.
Journal of the American Chemical Society
|July 9, 2014
概括
一种新的素连接体显著改善了催化西-赫克反应,用于制备基. 这种第二代催化剂最大限度地减少了基异构,从而提高了有价值的基产品的产量.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 合成有机化学 合成有机化学
背景情况:
- 基-赫克反应是合成基基的有价值的方法.
- 这种反应的第一代催化剂遭受了基异构化,降低了产品产量.
- 合理的连接体设计对于优化催化性能至关重要.
研究的目的:
- 通过催化西-赫克反应来开发第二代联体,以改善艾利西合成.
- 为了抑制与以前的催化剂观察到的烯异构.
- 阐明新连接体的电子和硬质性质,并了解催化系统.
主要方法:
- 理性连接体设计和新型素连接体的合成: bis ((3,5-di-tert-butylphenyl) ((tert-butyl) 素.
- 使用简单的基原始材料,以为催化剂的西-赫克反应.
- 谱学和晶体学分析以表征连接物特性和复合物.
主要成果:
- 新的联体物 bis3,5-di-tert-butylphenyl) ((tert-butyl) 素,有效地抑制了基异构化.
- 从简单的基基前体中获得了极大提高的基基基的产量.
- 量化了连接体的电子和硬质性质,提供了对催化剂行为的洞察.
- 一个复合物的X射线晶体结构揭示了有关催化系统的细节.
结论:
- 开发的第二代素连接体代表了催化西-赫克反应的重大进步.
- 这种新结合体使得具有极小副作用的艾利西兰的高效合成成为可能.
- 对复合物的结构洞察力有助于理解和进一步完善催化机制.
相关概念视频
Preparation and Reactions of Sulfides
4.3K
Sulfides are the sulfur analog of ethers, just as thiols are the sulfur analog of alcohol. Like ethers, sulfides also consist of two hydrocarbon groups bonded to the central sulfur atom. Depending upon the type of groups present, sulfides can be symmetrical or asymmetrical. Symmetrical sulfides can be prepared via an SN2 reaction between 2 equivalents of an alkyl halide and one equivalent of sodium sulfide.
4.3K
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
2.6K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
2.6K
Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
6.8K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
6.8K
Preparation of Alkynes: Alkylation Reaction
9.2K
Introduction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
9.2K
Radical Substitution: Allylic Bromination
5.2K
In organic synthesis, the formation of products can be altered by changing the reaction conditions. For example, a dibromo addition product is formed when propene is treated with bromine at room temperature. In contrast, propene undergoes allylic substitution in non-polar solvents at high temperatures to give 3-bromopropene. In order to avoid the addition reaction, the bromine concentration must be kept as low as possible throughout the reaction. This can be achieved using N-bromosuccinimide...
5.2K
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
10.9K
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.
10.9K


