IBiox[(-) -メンチル]:ステリカルに要求されるキラルなNHCリガンドである
Sebastian Würtz1, Claudia Lohre, Roland Fröhlich
1Organisch-Chemisches Institut der Westfälischen Wilhelms-Universität Munster, Corrensstrasse 40, 48149 Münster, Germany.
Journal of the American Chemical Society
|June 3, 2009
まとめ
新しいキラルなNHCリガンドであるIBiox[(-) -メンチルが合成されました. このステリカルに要求されるリガンドは,高度にエナチオセレクティブのアルファアリレーションとオキシンドール形成を可能にし,99%のエナチオメール過剰を達成します.
科学分野:
- 有機金属化学 有機金属化学
- アシンメトリック・カタリシス
- リンガンドデザイン リンガンドデザイン
背景:
- 立体的に要求するリガンドは,触媒の反応性と選択性を制御するために不可欠です.
- N-ヘテロサイクリックカルベン (NHCs) は,有機金属化学における多用途リガンドである.
- C-C結合形成における高いエナチオ選択性の達成は,依然として重要な課題です.
研究 の 目的:
- 小説を合成し,特徴づけるために,ステリカルに要求される,キラルなNHCリガンド.
- パラジウム触媒反応におけるリガンドの有用性を調査する.
- 価値ある有機化合物の非対称合成におけるその応用を探求する.
主な方法:
- IBiox[(-) -メンチル]リガンドの合成と構造的特徴.
- アリルクロライド基板を用いたパラジウム触媒による分子内アルファアリレーション反応.
- オキシンドールのエナチオセレクティブ合成.
主要な成果:
- 新しいNHCリガンド,IBiox[(-) -メンチルは,成功裏に準備され,特徴づけられました.
- リガンドは,約50%の埋もれた体積で,有意なステリック・バルクを示しています.
- リガンドは,アリル塩化物との分子内アルファアリレーションを促進し,高度にエナチオセレクティブなオキシンドール合成 (最大99% ee) を可能にしました.
結論:
- IBiox[(-) - メンチル]は,報告されている最もステリカルに要求される単歯性NHCリガンドの1つです.
- 独特のステリックおよび電子特性により,C−C結合形成に挑戦することができます.
- このリガンドは,特にオキシンドール合成のための非対称な触媒の重要な進歩を表しています.
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