Fe/Ti のシネージズム 地域選択 アレネ 不機能化
Yi-Ming Wei1, Xiao-Di Ma1, Meng-Fei Wang1
1College of Chemistry, Beijing Normal University, Beijing 100875, China.
Journal of the American Chemical Society
|January 9, 2023
まとめ
この研究では,ポリ置換アレンを地域選択的に合成するための新しい鉄/チタン (Fe/Ti) 方法が導入されています. この新しいアプローチは,正確なオーソディファンクショナライゼーションのためにユニークなヘテロメタリック中間物質を使用します.
科学分野:
- 有機化学
- 有機金属化学
- 合成方法論
背景:
- アレンの地域選択的機能不全は有機合成における重要な課題である.
- 既存の方法はしばしば一般性や置換物の配置に対する制御が欠けている.
研究 の 目的:
- ポリ置換アレンの地域選択合成のための新しい一般的な方法論を開発する.
- 鉄とチタンの相乗触媒によるアレンのオーソディファンクショナライゼーションを実現する.
主な方法:
- 鉄/チタン (Fe/Ti) のシネジスティックな触媒システムを採用した.
- アレンの地域選択的E/E'とNu/Eのオーソディファンクショナライゼーション反応を調査した.
- 新しい1,2-Fe/Tiヘテロメタリックアリレン中間体を特徴付けました.
主要な成果:
- 様々なポリ置換アレンを合成する一般的なFe/Tiのシンジェスティック方法論を成功裏に実証した.
- E/E'とNu/Eの2つの経路における高い地域選択性を達成した.
- 1,2-Fe/Tiヘテロメタリックアリレン中間物質が 反応の選択性にとって 決定的に重要であることが判明した.
結論:
- 開発された Fe/Ti シンジェスティック・メソドロジーは,地域選択的な機能化のための強力な新しいツールを提供します.
- 提案された1,2-Fe/Tiヘテロメタリック中間体は,観測された地域選択性に関する重要なメカニズム的な洞察を提供します.
関連する概念動画
Regioselectivity and Stereochemistry of Hydroboration
8.3K
A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn...
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn...
8.3K
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
Regioselectivity of Electrophilic Additions-Peroxide Effect
8.8K
In the presence of organic peroxides, the addition of hydrogen bromide to an alkene yields the isomer that is not predicted by Markovnikov’s rule. For example, the addition of hydrogen bromide to 2-methylpropene in the presence of peroxides gives 1-bromo-2-methylpropane. This addition reaction proceeds via a free radical mechanism, which reverses the regioselectivity. The free radical reaction mechanism involves three stages: initiation, propagation, and termination.
8.8K
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
10.4K
The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
10.4K
Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule
14.6K
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...
14.6K
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
10.6K
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.
10.6K


