通过对阴离子M4L6组件进行异质超分子催化
Hiroyuki Miyamura1,2, Robert G Bergman1, Kenneth N Raymond1
1Chemical Sciences Division, Lawrence Berkeley National Laboratory and Department of Chemistry, University of California-Berkeley, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|November 2, 2020
概括
聚合物中的固定超分子催化剂为连续流反应提供了增强的活性和耐久性. 这种异质系统模仿酶,使得高效和可重复使用的非对称催化.
科学领域:
- 超分子化学
- 催化剂
- 聚合物科学
背景情况:
- 大多数超分子催化剂的作用均,与自然的膜结合酶不同.
- 开发异质超分子催化剂对于模仿酶系统至关重要.
- 需要固定化策略来制造强大且可重复使用的催化剂.
研究的目的:
- 开发一个异质的超分子催化剂系统.
- 研究聚合物矩阵中固定超分子的催化性能.
- 探索非对称催化剂的潜力,使用固定化性超分子催化剂.
主要方法:
- 将性超分子聚合物 (Ga416) 固定成具有阴离子功能的交联聚合物.
- 在aza-Prins和aza-Cope反应中应用异质催化剂.
- 在连续流反应中对催化剂性能进行评估,包括耐久性,周转率和反选择性.
主要成果:
- 与可溶性催化剂相比,固定化的超分子催化剂表现出更强的活性和稳定性.
- 在连续流动反应中观察到高耐久性和持续的高回转率.
- 在回收和重复使用时,实现了不对称的催化,并保持了活性和酶选择性.
- 聚合物支中的酸结构影响了催化剂的稳定性,反应性和反选择性.
结论:
- 异质化超分子催化剂的性能可以超过同质的催化剂.
- 在连续流动的不对称催化过程中,固定化上分子有效.
- 聚合物支设计,特别是阴离子功能,在催化剂性能中起着至关重要的作用.
相关概念视频
Catalysis
29.4K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
29.4K
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.7K
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...
3.7K
Cationic Chain-Growth Polymerization: Mechanism
2.6K
The cationic polymerization mechanism consists of three steps: initiation, propagation, and termination. In the initiation step of the polymerization process, the π bond of a monomer gets protonated by the Lewis acid catalyst, which is formed from boron trifluoride and water. The protonation of the π bond generates a carbocation stabilized by the electron‐donating group. In the propagation step, the π bond of the second monomer acts as a nucleophile and attacks the...
2.6K
Olefin Metathesis Polymerization: Overview
2.4K
Recently, the development of olefin metathesis polymerization advanced the field of polymer synthesis. Simply put, the reorganization of substituents on their double bonds between two olefins in the presence of a catalyst is known as the olefin metathesis reaction. The use of metathesis reaction for polymer synthesis is called olefin metathesis polymerization.
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists of a...
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists of a...
2.4K


