AuI - ハロアルキンの触媒化水酸化
Pedro D García-Fernández1, Javier Iglesias-Sigüenza1, Paula S Rivero-Jerez1
1Departamento de Química Orgánica, Universidad de Sevilla and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Sevilla 41012, Spain.
Journal of the American Chemical Society
|August 20, 2020
まとめ
触媒のコントラニオンは,アルキンとハロアルキンの間の金触媒反応の反応経路を決定する. 異なるアニオンは,特定のステレオ化学的結果を持つハロアルキンとハロエニンを含む異なる製品につながります.
科学分野:
- 有機金属化学
- カタリシス
- 有機合成
背景:
- 金で触媒化された反応は,多用途の合成経路を提供します.
- 反応メカニズムの理解は,触媒の設計に不可欠です.
- アルキンの機能化におけるステレオ選択性の制御は,依然として重要な課題である.
研究 の 目的:
- アルキンとハロアルキンの黄金で触媒化された反応に対する触媒対アニオンの影響を調査する.
- 異なる反応経路とステレオ化学的結果を解明する.
- 水素アルキニル化経路のメカニズムと速度決定のステップを決定する.
主な方法:
- 金 ((I) カタリシスによって異なる対対離子 (BArF4,トリフラート).
- 終端アルキンと芳香アルキンの使用
- 運動分析と同位体標識を含む実験研究.
- 反応メカニズムを調査するための計算研究 (DFT).
主要な成果:
- 配合しないアニオン (BArF4) を含むカチオン黄金複合体は,シス-ハロアルキニル化を促進する.
- 弱塩基のトリフラートアニオンを持つ金 (I) 複合体は,トランス選択的水素アルキニル化製品 (ヘロエニン) を生成する.
- ハイドロアルキニレーションは,トリフラートによって促進されるアルキンのハロアルキンへの核愛攻撃によって行われます.
- プロトデオウレーションは,水素アルキニル化におけるターンオーバーを制限するステップとして識別される.
結論:
- 触媒対アニオンは,金で触媒化されたアルキンの反応における反応性と選択性の決定要因である.
- この研究は,ステレオ選択的水アルキニル化に関するメカニズム的洞察を提供します.
- この研究により,特定の合成変換のための金製の触媒を設計する基盤が提供される.
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