ピアノ・ストール・ルテニウム・カルベンの複合体によるエニンの水素化メタテシス
Sebastian Peil1, Giovanni Bistoni1, Richard Goddard1
1Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany.
Journal of the American Chemical Society
|October 19, 2020
まとめ
内部アルキンのゲミナル水素化は,両方の水素原子がアルキンの1つの炭素に加わる新しい変換である. このルテニウム触媒反応は,サイクロプロパネーション,メタテシス,およびC-H機能化の経路を提供します.
科学分野:
- 有機金属化学
- カタリシス
- 合成有機化学
背景:
- 内部アルキンのゲミナル水素化は,最近発見された変換である.
- この反応は,二水素からアルキンの単一の炭素原子への両水素原子の移転を含みます.
- このプロセスは,金属カルベンの複合体を反応性中間物として生成します.
研究 の 目的:
- 内アルキンのゲミナル水素化のメカニズムと範囲を調査する.
- サイクロプロパネーションと転移経路の選択性を制御する要因を理解する.
- この変換を天然製品の総合合成に適用し,新しい合成用途を探求する.
主な方法:
- ゲミナル水素化のための触媒として[Cp*RuCl]4を使用した.
- 反応結果を決定するために様々なアルケンの体系的な調査を行った.
- 反応メカニズムを解明するために,ローカルカップルされたクラスターレベルの理論で計算研究を行った.
- ルテニウムカルベンの中間物質をX線微分法で分離し,特徴づけました.
主要な成果:
- オレフィンの置換パターンは,サイクロプロパネーションまたは転移が起こるかどうかを決定する.
- 予測モデルが開発され,反応選択性を二重結合の極化とカルベン複合体の安定性に関連付けました.
- シヌラロンEとFの全合成における"水素代謝"の最初の適用は,提案された構造を確認した.
- ゲミナルの水素化は,C-H機能化と,シリ化アルキンの水素化メタテシスへの参加を可能にし,アルリシランの構成要素を生成する.
結論:
- ゲミナル水素化は,電子的および固体的因子に基づいて予測可能な選択性を持つ多用途の変換である.
- 開発されたモデルは,新しい触媒反応を設計するための貴重な洞察を提供します.
- この方法論は,天然製品の合成と価値ある有機シリコン化合物の作成における合成の可能性を拡大します.
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