アリルボロンエステルのフッ素化は,ビスムート・リドックス・カタリシスによって可能である
Oriol Planas1, Feng Wang1, Markus Leutzsch1
1Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany.
Science (New York, N.Y.)
|January 18, 2020
まとめ
この研究は,ビスムート (III) /ビスムート (V) 還元サイクルによる効率的なアリルボロンエステル化を可能にする,移行金属のような反応を行うことができる新しいビスムート複合体を導入する.
科学分野:
- 有機金属化学
- カタリシス
- 化化学
背景:
- 伝統的なビスムート触媒は,固定された酸化状態のルイス酸性を利用する.
- 触媒サイクルにおけるビスムスの酸化還元能力の限られた探索.
- 選択的なC−F結合形成のための新しい触媒システムの必要性
研究 の 目的:
- 伝統的なルイス酸度を超えた反応性を示す新しいビスムート複合体を開発する.
- アリルボロンエステルの化のためのビスムートベースの触媒システムを確立する.
- ビスマス媒介による化反応のメカニズムを解明する.
主な方法:
- 新しいビスマス複合体の合成と特徴付け.
- サルフォキシミン分子を用いたリガンド最適化.
- 結晶分析と反応モニタリングを含むメカニズム研究.
- アリルボロンエステル化のための触媒試験
主要な成果:
- 酸化的添加,還元的除去,および伝達が可能なビスムート複合体を実証した.
- アリルボロンエステルの化に有効なスルフォキシミン結合ビスムート触媒を特定した.
- ビスムス (III) /ビスムス (V) リドックスサイクルが鍵となるメカニズムとして確立された.
- クリスタログラフィーデータは,ビスムスの主要中間物質の構造に関する洞察を提供した.
結論:
- 新しいビスムスの複合体は 移行金属の反応性を模倣し,ビスムスの触媒的有用性を拡張します.
- 開発された触媒は,酸化還元活性ビスムートセンターを通して効率的なC-F結合形成を可能にします.
- ビスムート還酸化サイクルを理解することは,将来のビスムートベースの触媒の設計に不可欠です.
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