イリジウム/モノデンテート・フォスフォラミジットは,N-アリルイミネスの非対称な水素化を触媒化します
Natasa Mrsić1, Adriaan J Minnaard, Ben L Feringa
1University of Groningen, Stratingh Institute for Chemistry, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Journal of the American Chemical Society
|June 18, 2009
まとめ
イリジウム/ピフォスの催化によるN-アリルアセトフェノンイミンの非対称な水素化により,高度にエナチオセレクティブな二次アミンが得られます. その後のデプロテクションにより,プライマリアミンは完全なエナチオセレクティブ性を有します.
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
- グリーン・ケミストリー (Green Chemistry)
背景:
- チラルアミンは,医薬品や微細化学薬品の重要な構成要素です.
- 効率的な非対称合成方法は,エナティオメリカルに純粋な化合物を生産するために不可欠です.
- N-アリルアセトフェノンイミンは,アミン合成のための多用途の前駆体である.
研究 の 目的:
- キラルなN-アリルアセトフェノンイミン誘導体を合成するための高度なエナンチオセレクティブの方法を開発する.
- 代替剤のエナチオ選択性に対する影響を調査する.
- プライマリアミンへのアクセスのための簡単な脱保護戦略を確立する.
主な方法:
- イリジウム/ピフォス触媒システムを用いたN-アリルアセトフェノンイミンの非対称な水素化.
- 反応条件の最適化により,エナチオ選択性を最大化します.
- トリクロイソシアヌル酸を用いた二次アミンの酸化去除.
主要な成果:
- 非対称な水素化において非常に高いエナチオ選択性 (最大99%) を達成した.
- アリル環の電子提供置換物質がエナチオ選択性を強化することを実証した.
- 二次アミンを初次アミンに変換し,エナチオセレクティブ性を完全に保持し,特に2メトキシ置換基質に対して,良好な収量で,二次アミンを初次アミンに変換しました.
結論:
- イリジウム/ピッフォスシステムは,N-アリルアセトフェノンイミンの非対称的水素化に非常に効果的です.
- 開発された方法は,エナチオメリックに濃縮されたプライマリアミンへの堅固な経路を提供します.
- このアプローチは,キラルアミンを含む分子の合成のための貴重なツールを提供します.
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