サイクリック・アリファティック・オキシカルベニウムイオンによる非対称な触媒
Sunggi Lee1, Philip S J Kaib1, Benjamin List1
1Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
Journal of the American Chemical Society
|February 8, 2017
まとめ
新しいイミドディフォスフォリミダート (IDPi) 触媒は,ラクトールアセテートとエノリシランから多様な酸素ヘテロサイクルを直接エナチオ選択的に合成し,優れたエナチオ選択性を達成します.
科学分野:
- 有機化学
- カタリシス
- 合成化学
背景:
- 酸素ヘテロサイクルは医薬品や天然製品に多く含まれています.
- これらのエナチオセレクティブ合成は,有機化学における重要な課題です.
研究 の 目的:
- 代替酸素ヘテロサイクルの直接的エナチオセレクティブ合成経路を開発する.
- この変換のために新しいイミドジフォスフィーミデート (IDPi) 触媒を使用する.
主な方法:
- ラクトールアセテートとエノルシランの反応
- 高反応性で閉じ込められたイミドディフォスフォリミダート (IDPi) 触媒を用いる.
- 反応産物のエナチオ選択性の分析
主要な成果:
- テトラヒドロフラン,テトラヒドロピラン,オクセパン,クロマン,ダイヒドロベンゾフランを含む様々な酸素ヘテロサイクルを直接選択合成する.
- 合成されたキラルヘテロサイクルのための優れたエナンチオセレクティビティを達成した.
- 周期性オキシカルベニウムイオンの中間物質を含む経路を示した.
結論:
- 開発されたIDPI触媒方式は,エナチオメリックに濃縮された酸素ヘテロサイクルへの効率的なアクセスを提供します.
- この方法論は複雑なキラル分子の合成のための貴重なツールを提供します.
- 閉じ込められたキラルコントラニオンは,エナチオ選択性を制御する上で重要な役割を果たします.
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