アルミニウム触媒によるヘテロアリルケトンの非対称な水酸化
Yury Lebedev1,2, Iuliia Polishchuk1,2, Bholanath Maity1
1King Abdullah University of Science and Technology (KAUST) KAUST Catalysis Center (KCC) , Thuwal 23955-6900 , Saudi Arabia.
Journal of the American Chemical Society
|November 9, 2019
まとめ
キラルリガンドを持つ高度に活性なメチルアルミニウム触媒は,ヘテロサイクルケトンの非対称的還元を効率的に実行します. この方法により,薬剤発見と触媒化に有用なキラルアルコールは得られ,高収量とエナチオ選択性が得られます.
科学分野:
- 有機金属化学
- 非対称な触媒
- 有機合成
背景:
- キラルアルコールは,医薬品と非対称な触媒における重要な中間物質である.
- エナチオセレクティブ合成のための効率的な触媒システムの開発は,依然として重要な課題です.
研究 の 目的:
- 非対称なケトン還元のための高度に活性で選択的なメチルアルミニウム触媒を開発する.
- 幅広い基板範囲でこれらの触媒の有用性を探求する.
主な方法:
- キラルバイフェノール型リガンドによるメチルアルミニウム複合体の合成.
- 開発された触媒を用いた様々なヘテロサイクルケトンの非対称的還元.
- 反応中間物の分離と特徴づけ
- 触媒メカニズムを解明するための密度関数理論 (DFT) の計算.
主要な成果:
- 触媒は高い活性 (S/C=100−500) と優れたエナチオ選択性 (最大99% ee) を示した.
- プロトコルでは,基板の範囲が広く,機能群の耐性が高いことが示された.
- キラル2ヘテロサイクリックアルコールは,有価な合成中間物質として得られた.
結論:
- キラルビフェノールリガンドを含むメチルアルミニウム複合体は,非対称ケトン還元のための効果的な触媒である.
- 開発された方法は,薬剤発見とリガンド開発のための重要なキラルビルディングブロックにアクセスできます.
- DFT計算は,提案された触媒サイクルをサポートし,メカニズム的な洞察を提供します.
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