内部アルキンからサイクロトリフォスファトルテニウム複合体でヴィニリデンの形成
Yousuke Ikeda1, Takafumi Yamaguchi, Keiichiro Kanao
1Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.
Journal of the American Chemical Society
|December 5, 2008
まとめ
ルテニウムサイクロトリフォスファト複合体は,内部アルキンのヴィニリデン再配置を触媒化する. この新しい反応は,アルキル,アリル,アシル群の移動に対して,分子内電友性プロセスを通じて高い汎用性を達成します.
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:
- 内部アルキンは,有機合成における汎用的な構成要素である.
- アルキンイソメリゼーション反応は,多様な分子構造へのアクセスに不可欠です.
- アルキーン変換のための新しい触媒システムの開発は,依然として活発な研究分野です.
研究 の 目的:
- アルキンの再配置におけるルテニウムサイクロトリフォスファト複合体の触媒的活性を調べる.
- アルキンからビニリデンのイソメリゼーションの範囲と一般性を探求する.
- 異なる機能群の反応機構と移動能力を解明する.
主な方法:
- ラビルメタノールリガンドによるルテニウムサイクロトリフォスファト複合体の合成と特徴付け.
- ルテニウム複合体の様々な内部アルキンとの反応.
- インターミディエイトエタ2アルキン複合体の分離と特徴付け.
- 反応メカニズムの探査のための運動学的研究.
主要な成果:
- ルテニウム複合体は,一般の内部アルキンのヴィニリデン再配置を効果的に触媒化する.
- 反応は,アルキル,アリル,アシル基を含む高度な汎用性で進行する.
- いくつかの中間型エタ2アルキン複合体は,成功裏に分離され,ヴィニリデネ製品に変換されました.
- 運動データと移住能力の研究は,分子内電子性再配置機構を示唆している.
結論:
- ルテニウムサイクロトリフォスファト複合体は,内部アルキンイソメリゼーションのための新種の触媒を代表しています.
- 開発された方法は,内部アルキンからヴィニリデン複合体を合成するための一般的な経路を提供します.
- 反応は,珍しい分子内電子性再配置経路を通過する.
さらに関連する動画
関連する概念動画
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Introduction
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Introduction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
Aldehydes and Ketones to Alkenes: Wittig Reaction Mechanism
The Wittig reaction, which converts aldehydes or ketones to alkenes using phosphorus ylides, proceeds through a nucleophilic addition‒elimination process.
The reaction begins with the nucleophilic addition between a phosphorus ylide and the carbonyl compound. Due to its carbanionic character, phosphorus ylide acts as a strong nucleophile and attacks the electrophilic carbonyl group. This generates a charge-separated dipolar intermediate called betaine. The negatively charged oxygen atom and...
The reaction begins with the nucleophilic addition between a phosphorus ylide and the carbonyl compound. Due to its carbanionic character, phosphorus ylide acts as a strong nucleophile and attacks the electrophilic carbonyl group. This generates a charge-separated dipolar intermediate called betaine. The negatively charged oxygen atom and...
Alkynes 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.


