アニオニック M4L6のアンモビライゼーションによる異質な超分子触媒
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
まとめ
ポリマーの固定された超分子触媒は,連続流動反応の活性と耐久性を高めます. この異質なシステムは酵素を模倣し 効率的で再利用可能な非対称な触媒を可能にします
科学分野:
- 超分子化学
- カタリシス
- ポリマー科学
背景:
- ほとんどの超分子触媒は,天然の膜結合酵素とは異なり,均質に作用する.
- 異質な超分子触媒の開発は 酵素システムを模倣するために不可欠です
- 頑丈で再利用可能な触媒を作るには 不動化戦略が必要です
研究 の 目的:
- 異質な超分子触媒システムを開発する
- ポリマーマトリックスにおける固定された超分子クラスターの触媒性能を調査する.
- 固定されたキラル超分子触媒を用いた非対称な触媒の可能性を調査する.
主な方法:
- クイラルな超分子クラスター (Ga416) を,カチオンの機能を持つ交絡ポリマーに固定する.
- アザ-プリンスとアザ-コップの反応における異質な触媒の適用
- 耐久性,周回量,およびエナチオ選択性を含む連続流動反応における触媒性能の評価.
主要な成果:
- 固定された超分子触媒は,溶解性同位体と比較して,活性と強度が向上した.
- 高耐久性と持続的な高回転が連続流動反応で観察された.
- 非対称な触媒は,回収と再利用時に活性とエナチオ選択性を維持した.
- ポリマー基体のアンモニアムカチオンの構造は,触媒の安定性,反応性,およびエナチオ選択性に影響を与えた.
結論:
- 異質化された超分子触媒は同質な触媒を上回る.
- 固定されたキラル上分子クラスターは,連続流動の非対称な触媒に有効です.
- ポリマー支柱の設計,特にカチオンの機能は,触媒の性能において重要な役割を果たします.
関連する概念動画
02:50Catalysis
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
02:17Reduction 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
00:57Cationic 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
01:13Olefin 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