自己組み立てのチタン触媒によって触媒化された芳香アルデヒドに高度なエナチオセレクティブ性アルキニルジンク添加
Xingshu Li1, Gui Lu, Wai Him Kwok
1Open Laboratory of Chirotechnology of the Institute of Molecular Technology for Drug Discovery and Synthesis and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong.
Journal of the American Chemical Society
|October 24, 2002
まとめ
BINOLと別のリガンドをチタンイソプロ酸化物と組み合わせた新しい触媒は,エナチオセレクティブアルキニルジンク添加を芳香アルデヒドに効果的に促進し,99%以上のエナチオセレクティブ性を達成します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- アシンメトリック・シンセシス
背景:
- エナチオセレクティブ合成は,医薬品と微細化学品にとって極めて重要です.
- アルキニルジンク反応剤は,炭素-炭素結合形成のための多用途な構成要素を提供します.
- 非対称アルキニル化のための効率的な触媒の開発は,依然として重要な課題です.
研究 の 目的:
- アルキニルジンク反応剤を芳香アルデヒドに添加するための高度なエナンチオセレクティブの触媒を開発する.
- 非対称アルキニル化におけるBINOL由来システムの触媒性能を調査する.
主な方法:
- BINOL (別のリガンド) とイソプロポキシドチタン (Ti(OiPr) (4) からキラル触媒を調製する.
- アロマティックアルデヒドとアルキニルジンク反応剤の反応.
- キラルクロマトグラフィを用いたエナンチオ選択性の分析.
主要な成果:
- 開発された触媒は,99%e.e.を超える非常に高いエナチオセレクティブ性を実証しました.
- 触媒システムは,アルキニルジンクを様々な芳香アルデヒドに添加するのに非常に効果的でした.
- BINOLと二次リガンドとTi ((OiPr)) 4の組み合わせは,観察された高いエナチオセレクティブ性にとって決定的であることが判明しました.
結論:
- 非対称アルキニレーションのための新しい,非常に効果的なキラル触媒が成功裏に開発されました.
- この触媒システムは,エナチオセレクティブの炭素-炭素結合形成における重要な進歩を表しています.
- この方法論は,芳香アルデヒドから派生したプロパルギルアルコールをエナティオメリックに濃縮するための実用的な経路を提供します.
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