光学的に活性なアトロピソメリックアニリドの効率的な合成は,触媒的非対称なN-アリレーション反応による
Osamu Kitagawa1, Masashi Takahashi, Masatoshi Yoshikawa
1Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
Journal of the American Chemical Society
|March 18, 2005
まとめ
この研究では,パラジウムアセテート触媒を用いた新しい触媒的非対称なN-アリレーション法を示しています. このプロセスは,光学的に活性なアトロピソメアアニリドと,高いエナチオ選択性を持つラクトームを効率的に生成します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- アシンメトリック・カタリシス
- 薬用化学 薬用化学について
背景:
- N-アリレーションは,有機合成における重要な反応である.
- N-アリレーションのためのエナンチオセレクティブ方法の開発は,キラル分子を作成するために重要です.
- N-Cキラル軸を持つアトロピソメア化合物は,医薬品において価値があります.
研究 の 目的:
- オルソ-テルト-ブチル-NH-アニリドの触媒的非対称なN-アリレーションを開発する.
- 光学的に活性なアトロピソメアアニリドとラクトームを合成する.
- これらの変換において高いエナチオセレクティビティを達成するために.
主な方法:
- (R) -DTBM-SEGPHOS-Pd(OAc) 2を触媒として使用しています.
- 4-ニトロイオドベンゼンとオルタートルチルブチルNHアニリドを反応させる.
- 分子間および分子内N-アリレーション反応の両方を実行します.
主要な成果:
- アニリドのN-アリレーションにおいて高いエナチオ選択性 (89~95% ee) を達成した.
- N-Cキラル軸を持つ光学的に活性なアトロピソメリックアニリドを合成しました.
- 高光学純度 (94-96% ee) のアトロピソメリックラクタムを分子内N-アリレーションで得られた.
結論:
- 開発された触媒システムは,非対称なN-arylationに対して有効である.
- この方法により,貴重なキラルアトロピソメア化合物にアクセスできます.
- このアプローチは,複雑な分子の分子間および分子内合成に適しています.
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