Ru-Catalyzed Migratory Geminal Semi-hydrogenation of Internal Alkynes to Terminal Olefins
Lijuan Song1,2, Qiang Feng3, Yong Wang3
1Lab of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics , Peking University Shenzhen Graduate School , Shenzhen 518055 , China.
Journal of the American Chemical Society
|October 10, 2019
まとめ
この研究は,アルキンの新しいゲミナル半水素化を導入し,貴重な末端ビニルシランを生成します. このプロセスはシリルアルキンの新しい反応モードを提供し,選択的なゲミナルまたはトランス添加を可能にします.
科学分野:
- 有機化学
- カタリシス
- 有機金属化学
背景:
- アルキンをアルケンに半化することは重要な合成変換である.
- 既存の方法は主にシスアルケンまたはトランスアルケンを生成する.
- 様々なアルケンの構造にアクセスするには新しい方法が必要です.
研究 の 目的:
- 内部アルキンの新しいゲミナル半水素化を開発する.
- シリルアルキンの新しい反応モードを探求する.
- ターミナルビニルシランへのアクセスを提供します.
主な方法:
- カチオン [CpRu(MeCN) 3PF6触媒を使用した.
- 様々なアリルとアルキル代替シリルアルキンを使用した.
- シリル群,添加物,H2圧力を含む最適化反応条件.
- 密度関数理論 (DFT) 研究を行い,そのメカニズムを明らかにした.
主要な成果:
- シリルアルキンの高効率で精選的な半水素化が達成された.
- 条件の最適化によって選択性をゲミナルからトランスに切り替える能力を示した.
- DFTの計算では,GEM-H2ル-カルベンの中間物質が鍵であり,ル-ビニリデンは鍵ではない.
- 制御実験は提案されたメカニズムを支持した.
結論:
- ゲミナル半水素化と1,2-シリル移行による末端ビニルシランへの新しい合成経路が確立されています.
- この研究は,ルテニウム触媒によるシリルアルキンの新しい反応パターンを明らかにした.
- この発見は,アルキンの変換のための合成ツールボックスを拡張します.
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