フォスフィン触媒による [4 + 2] 解消:高度に機能化されたテトラヒドロピリジンの合成
Xue-Feng Zhu1, Jie Lan, Ohyun Kwon
1Department of Chemistry, University of California, Los Angeles, California 90095-1569, USA.
Journal of the American Chemical Society
|April 17, 2003
まとめ
新しいフォスフィン触媒による無効反応は,エチル2-メチル-2,3-ブタディエノアートを1,4-二極シントンとして使用して,代用されたテトラヒドロピリジンを効率的に合成します. この方法は,さまざまなピリジン誘導体に対して,優れた収穫量,地域選択性,およびダイアステレオ選択性を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 合成化学 合成化学とは
- カタリシス カタリシス カタリシス
背景:
- 1,4-二極シンソンは,有機合成における貴重な構成要素である.
- テトラヒドロピリジン・スキャフォールドは,医薬品や天然製品に多く見られます.
- ヘテロサイクルの合成のための効率的な触媒方法の開発は極めて重要です.
研究 の 目的:
- テトラヒドロピリジン合成のための新しい [4 + 2] キャンセル反応を開発する.
- エチル2-メチル-2,3-ブタディエノアートを新しい1,4-二極シントンとして利用する.
- 開発された無効化の範囲とステレオ選択性を調査する.
主な方法:
- エチル2-メチル-2,3-ブタディエノアートがN-トシリミンと反応する.
- [4 + 2] 解消のために有機フォスフィン触媒を使用する.
- 適用範囲を拡大するために,代用されたエチル2−(代用されたメチル) -2,3-ブタディエノアートを利用する.
主要な成果:
- エチル6-置換-1-(4-トシル) -1,2,5,6-テトラヒドロピリジン-3-カルボキシラートに対して,優れた収穫量と完全な地域選択性が達成されました.
- 反応範囲の拡大により,エチル2,6-シス-非置換-1-(4-トシル) -1,2,5,6-テトラヒドロ-ピリジン-3-カルボキシラートが得られた.
- 高度のダイアステロセレクティビティは,代用品の合成で観察されました.
結論:
- 新しい効率的なフォスフィン触媒による [4 + 2] 解消反応が確立されました.
- エチル2-メチル-2,3-ブタディエノアートは,テトラヒドロピリジン合成のための効果的な1,4-二極シントンとして機能します.
- この反応は,制御された立体化学で高度に置換されたテトラヒドロピリジンへの多用途の経路を提供します.
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