![Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F51444.jpg&w=3840&q=50)
ニッケル/マグネシウムのバイメタリック協力によるニッケル触媒クロスカップリングのためのヒドロキシホスフィンリガンド
Naohiko Yoshikai1, Hirokazu Matsuda, Eiichi Nakamura
1Department of Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|June 16, 2009
まとめ
ハイドロキシホスフィン (PO) リンガンドは,挑戦的なアリル電ophilesとグリニャード反応剤とのニッケル触媒クロスカップリング反応を加速します. この新しいシステムは,非反応性アリルハリドおよびフェノール誘導体を効率的に活性化して,貴重なクロスカップリング製品を生成します.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- ニッケル触媒によるクロスカップリング反応は,C−C結合形成に不可欠である.
- 非反応性アリル電ophilesの活性化は,触媒の重要な課題であり続けています.
研究 の 目的:
- 非反応性アリル電ophilesの効率的なクロスカップリングのための新しい触媒システムを開発する.
- 強化された触媒活動の背後にあるメカニズムを調査する.
主な方法:
- ニッケル触媒とグリニャード反応剤を用いたヒドロキシホスフィン (PO) リガンドを使用した.
- 運動同位体効果実験と密度関数理論 (DFT) の計算を機械学的研究のために採用した.
主要な成果:
- 非反応性アリルハリド (フッ化物,塩化物,ポリハリド) およびフェノール派生物 (カルバマート,リン酸塩) の容易活性化が達成される.
- 取得したクロスカップリング製品は,良質から優れた収量で得られます.
- 活性触媒としてニッケル・フォスフィン/マグネシウム・アルコシド双金属種を特定した.
結論:
- ニッケル-PO-グリナードシステムは,クロスカップリング反応を大幅に加速します.
- バイメタリック種を含む新しいC-X結合活性化メカニズムが提案され,実験データと計算データによって支持されました.
- この研究は,電性基板活性化のための均質な触媒システムの設計のための新しい概念を提供します.
さらに関連する動画
12:08Catalytic Reactions at Amine-Stabilized and Ligand-Free Platinum Nanoparticles Supported on Titania During Hydrogenation of Alkenes and Aldehydes
Published on: June 24, 2022
05:48Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
関連する概念動画
02:51Metal-Ligand Bonds
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
02:50Catalysis
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.
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...
01:19Complexation Equilibria: The Chelate Effect
In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...
00:43Complexometric Titration: Ligands
Different monodentate and polydentate ligands are used as complexing agents in complexometric titration reactions. The formation of complexes by mono- and bidentate ligands involves two or more intermediate steps, limiting their use as complexing agents. In comparison, polydentate ligands can form complexes with metal ions in a single-step process, facilitating sharper end points. This means polydentate ligands, such as amino carboxylic acid derivatives, are most commonly employed in...
01:22Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction
The radical dimerization of ketones or aldehydes gives vicinal diols through a pinacol coupling reaction. However, the behavior of titanium metals used for the reaction as a source of electrons is unusual. When the reaction is carried out in the presence of titanium, diols can be isolated at low temperatures. Else titanium further reacts with diols, forming alkenes through the McMurry reaction.