エナチオセレクティブA(3) 二次アミンの反応は,Cu(I) /酸-チオウレア触媒の組み合わせによるものです
1Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States.
Journal of the American Chemical Society
|April 4, 2015
まとめ
この研究は,ピロリジンからプロパルギラミンを合成するための効率的な銅触媒非対称性A (3) 反応を導入しています. この方法は,高いエナチオセレクティブ性を達成し,その後,エナチオピュアアレンに変換することを可能にします.
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:
- A(3) カップリング反応は,プロパルギラミン合成の貴重な方法である.
- 効率的でエナチオセレクティブな触媒システムの開発は,有機合成における重要な課題であり続けている.
研究 の 目的:
- ピロリジンおよび関連するアミンを用いて,銅触媒による新しい非対称性A (((3) 反応を開発する.
- プロパルギラミンの合成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.
- 合成プロパルギラミンのアルレンへの変換を調査する.
主な方法:
- 非対称 A(3) 反応は,イオジ銅 (CuI) を触媒として使用する.
- カーボキシル酸とチオウレア基の両方を含む二機能コカタリストを用いて.
- 触媒の負荷と温度を含む反応条件の最適化.
- プロパルギラミンからアレンへの後の変換.
主要な成果:
- プロパルギラミンは,高いエナティオメリック過剰 (96%eまで) で合成されました.
- 低触媒負荷 (1mol%以下) が有効であった.
- ピロリジン由来プロパルギラミンは,エナンチオピュリティを失うことなくアレンに変換されました.
結論:
- 新しく効率的な銅触媒による非対称性反応A(3) が確立されました.
- 開発された方法は,高度にエナチオピュアなプロパルギラミンとアレンへのアクセスを提供します.
- 二機能コカタリストは,高いエナンチオセレクティビティを達成する上で重要な役割を果たします.
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