ルテニウムアルキリデン複合体の非メタテティック活性:マルチエンの1,4-ヒドロビニラティブサイクライゼーションとエチレン
Sang Young Yun1, Kung-Pern Wang, Mansuk Kim
1Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607-7061, USA.
Journal of the American Chemical Society
|June 20, 2012
まとめ
ルテニウム触媒は,エチレンを使用したアルキンの効率的なサイクルを可能にします. 反応 反応 反応する
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- 合成方法論 合成方法論
背景:
- サイクル反応は,複雑な分子構造を構築するための有機合成の基本です.
- ルテニウム触媒反応は,炭素-炭素結合形成のためのユニークな経路を提供します.
- 水酸化ビニル化反応は,価値ある合成ハンドルであるビニル群を導入します.
研究 の 目的:
- トラインとテトラインの効率的な1,4-ヒドロビニラティブサイクリングを開発する.
- この変換におけるルテニウムアルキリデン複合体の触媒的活性を調べる.
- ヴィニールグループ組み込みにおける地域選択性の制御を調査する.
主な方法:
- ルテニウムアルキリデン複合体を触媒として使用する.
- エチレンをビニル源として利用する.
- サイクルトラインとテトラインを最適化された条件下で反応させる.
主要な成果:
- トラインとテトラインの効率的な1,4-ヒドロビニラティブサイクリングが達成されました.
- ルテニウムアルキリデン複合体,特にグラブスの第2世代の触媒は,高い有効性を示しました.
- ビニル群の組み込みの地域選択性は,アルキン置換剤の改変によってうまく制御されました.
結論:
- ルテニウムアルキリデンの複合体は,アルキンのサイクル化のための効果的な触媒システムを提供します.
- 開発された方法は,サイクル構造にビニル群を組み込むための制御されたアプローチを提供します.
- この反応は,有機合成におけるルテニウム触媒の合成的有用性を拡大する.
関連する概念動画
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
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.
01:13Olefin Metathesis Polymerization: Overview
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...
02:35Electrophilic Addition to Alkynes: Hydrohalogenation
Electrophilic addition of hydrogen halides, HX (X = Cl, Br or I) to alkenes forms alkyl halides as per Markovnikov's rule, where the hydrogen gets added to the less substituted carbon of the double bond. Hydrohalogenation of alkynes takes place in a similar manner, with the first addition of HX forming a vinyl halide and the second giving a geminal dihalide.
01:12Cycloaddition Reactions: MO Requirements for Photochemical Activation
Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
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...
02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
Introduction
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.