エナンチオセレクティブアミノキシル基素触媒の一般性指向型最適化
Jonas Rein1, Soren D Rozema2, Olivia C Langner2
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA.
まとめ
この研究は,単純なダイオルからキラル分子を生成するための新しい触媒法を導入しています. 開発された触媒は様々な基板にわたって非常に有効であり,非対称合成の重要な進歩を提供します.
科学分野:
- 有機化学
- カタリシス
- アシンメトリック・シンセシス
背景:
- 広く適用可能な触媒エナチオセレクティブの方法の開発は依然として課題です.
- メゾダイオルの酸化脱対化は,キラル化合物を生成するための重要な変換である.
研究 の 目的:
- メソダイオルの酸化脱対化のための一般的触媒戦略を開発する.
- 幅広い基板で高いエナチオ選択性を達成する.
主な方法:
- スクリーニング基板を使用した非伝統的な触媒最適化プロトコルを使用しました.
- アミノキシル基の活性残基を含むペプチド触媒配列の合理的調節
主要な成果:
- エナンチオ濃縮ラクトンに対する高い選択性を示す一般的な触媒が特定されました.
- この方法は,幅広いダイオール基板において有効であることが証明された.
- 極めて高い触媒回転率 (最大100,000回) を達成した.
結論:
- 開発された触媒システムは,エナチオセレクティブ合成における重要な進歩を表しています.
- 基板に焦点を当てた最適化アプローチは,一般的な触媒を発見するのに有効です.
- この方法は,エンアンチオイン濃縮ラクトンへのアクセスに強力なツールを提供します.
関連する概念動画
Radical Anti-Markovnikov Addition to Alkenes: Overview
3.4K
The addition of hydrogen bromide to alkenes in the presence of hydroperoxides or peroxides proceeds via an anti-Markovnikov pathway and yields alkyl bromides.
3.4K
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.4K
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...
3.4K
Sharpless Epoxidation
4.1K
The conversion of allylic alcohols into epoxides using the chiral catalyst was discovered by K. Barry Sharpless and is known as Sharpless epoxidation. The use of a chiral catalyst enables the formation of one enantiomer of the product in excess. This chiral catalyst is mainly a chiral complex of titanium tetraisopropoxide and tartrate ester (specific stereoisomer). The stereoisomer used in the chiral catalyst dictates the formation of the enantiomer of the product. In other words, the use of...
4.1K
Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule
14.4K
If a set of reactants can yield multiple constitutional isomers, but one of the isomers is obtained as the major product, the reaction is said to be regioselective. In such reactions, bond formation or breaking is favored at one reaction site over others.
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
14.4K
Radical Reactivity: Nucleophilic Radicals
2.1K
Radicals adjacent to electron-donating groups are called nucleophilic radicals. These radicals readily react with electrophilic alkenes. The SOMO–LUMO interactions are the driving force for the reaction, where the high-energy SOMO of the electron-rich, nucleophilic radicals interacts with the low-energy LUMO of the electron-deficient, electrophilic alkenes. Such SOMO–LUMO interactions are the basis of reactive radical traps, affecting the selectivity in radical reactions. For...
2.1K
Radical Anti-Markovnikov Addition to Alkenes: Mechanism
3.9K
The reaction of hydrogen bromide with alkenes in the presence of hydroperoxides or peroxides proceeds via anti-Markovnikov addition. The radical chain reaction comprises initiation, propagation, and termination steps.
The mechanism starts with chain initiation, which involves two steps. In the first chain initiation step, a weak peroxide bond is homolytically cleaved upon mild heating to form two alkoxy radicals. In the second initiation step, a hydrogen atom is abstracted by the alkoxy...
The mechanism starts with chain initiation, which involves two steps. In the first chain initiation step, a weak peroxide bond is homolytically cleaved upon mild heating to form two alkoxy radicals. In the second initiation step, a hydrogen atom is abstracted by the alkoxy...
3.9K


