N-Boc-pyrrolidineのエナチオセレクティブ,パラジウム触媒化されたアルファアリレーションである
Kevin R Campos1, Artis Klapars, Jacob H Waldman
1Department of Process Research, Merck Research Laboratories, P.O. Box 2000, Rahway, New Jersey 07065, USA. kevin_campos@merck.com
Journal of the American Chemical Society
|March 16, 2006
まとめ
この研究は,N-Boc-pyrrolidineの新しいエナチオセレクティブのパラジウム触媒アルファアリレーションを導入しています. この方法は,高いエナティオメリック比率 (er) を有するキラル-2-アリル-N-ボック-ピロリジンを効率的に合成します.
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
- 合成方法論 合成方法論
背景:
- チラルピロリジン誘導体は,医薬品や天然製品の重要な構成要素です.
- それらの合成のための効率的でエナチオセレクティブな方法の開発は,有機化学における重要な課題です.
研究 の 目的:
- N-Boc-ピロリジンの最初のエナンチオセレクティブのパラジウム触媒アルファ-アリレーションを報告する.
- 高いエナチオ選択性を持つ多様な2-アリル-N-ボク-ピロリジンを合成するための信頼性の高いコンバージェントな方法の確立.
主な方法:
- スパルテインを用いたN-Boc-ピロリジンのエナンチオセレクティブデプロトネーションにより,2-ピロリジノリチウム種が生成される.
- 亜鉛塩化物とのトランスメタライゼーションにより,ステレオ化学的に硬直した2ピロリディノジンク反応剤が形成されます.
- 亜鉛反応剤と機能化されたアリルハリドを室温でパラジウム触媒で結合する.
主要な成果:
- 高いエナティオメール比率 (一貫して96:4er) を有する多様な2-アリル-N-ボック-ピロリジン合成に成功しました.
- 低触媒負荷 (0.3 亜鉛のequiv) で実証された効率.
- 亜鉛反応剤のステレオ化学的安定性は60°Cまでである.
- 主要な例として, (R) ニコチンのエナチオセレクティブ合成.
結論:
- 開発された方法論は,エナチオメリックに濃縮された2-アリル-N-ボック-ピロリジンへの収束し,信頼性の高い経路を提供します.
- このアプローチは,価値あるキラル型ピロリジン誘導体の合成において,著しい進歩をもたらします.
関連する概念動画
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