Ni-Catalyzed Regioselective AlkynesのCO2によるアルキンの炭化水素酸化は,陽子の源として単純なアルコールを使用することによって行われる
Xueqiang Wang1, Masaki Nakajima1, Ruben Martin1,2
1†Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007 Tarragona, Spain.
Journal of the American Chemical Society
|July 2, 2015
まとめ
新しいニッケル触媒反応は,アルキンと二酸化炭素を効率的に単純なアルコールを用いて価値ある製品に変換します. このユーザーフレンドリーな方法は,広範な適用性を提供し,よりグリーンな化学合成のために厳しい反応剤を避けます.
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
- グリーン・ケミストリー (Green Chemistry)
背景:
- アルキンのヒドロカルボキシル化がカルボキシル酸を合成するための重要な変換である.
- 既存の方法は,しばしば厳しい条件,敏感な反応剤,または地域選択性がないことを要求します.
研究 の 目的:
- 二酸化炭素を用いたアルキンの温和で,ユーザーフレンドリーで,地域選択的炭化水素酸化を開発する.
- 前例のない地域選択性パターンを持つ新しい触媒システムを確立する.
主な方法:
- 炭素二酸化物 (1バー) と様々なアルキンのニッケル触媒反応.
- プロトン源として単純なアルコールを利用した.
- 軽度の反応条件を採用し,繊細な有機金属種を避ける.
主要な成果:
- 高効率でアルキンの地域選択的炭化水素酸化を達成した.
- 広範な基板の範囲を示し,プロトコルの汎用性を示しました.
- アルコールの選択によって引き起こされる,前例のない地域選択性のパターンを確立した.
結論:
- 開発されたNi-触媒プロトコルは,アルキンの炭化水素酸化のための穏やかで持続可能な経路を提供します.
- この方法は,幅広い範囲とユニークな地域選択性を持つユーザーフレンドリーな代替手段を提供します.
- このプロトコルは,CO2から価値あるカルボキシル酸誘導体の合成を容易にする.
関連する概念動画
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
9.6K
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.
9.6K
02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
22.0K
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.
22.0K
02:40Alkynes to Aldehydes and Ketones: Acid-Catalyzed Hydration
11.5K
Introduction
Analogous to alkenes, alkynes also undergo acid-catalyzed hydration. While the addition of water to an alkene gives an alcohol, hydration of alkynes produces different products such as aldehydes and ketones.
Analogous to alkenes, alkynes also undergo acid-catalyzed hydration. While the addition of water to an alkene gives an alcohol, hydration of alkynes produces different products such as aldehydes and ketones.
11.5K
02:34Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
10.1K
The rate of acid-catalyzed hydration of alkenes depends on the alkene's structure, as the presence of alkyl substituents at the double bond can significantly influence the rate.
10.1K
02:36Regioselectivity and Stereochemistry of Hydroboration
9.8K
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 stereochemistry.
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 stereochemistry.
9.8K
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
4.0K
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...
4.0K