ビスチオウレア-水素結合ドナーによって触媒化されたステレオ特異のフラノシレーション
Andrew B Mayfield1, Jan B Metternich1, Adam H Trotta1
1Department of Chemistry & Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , United States.
Journal of the American Chemical Society
|February 5, 2020
まとめ
新しいビスチオウレア触媒は,ステレオ選択的O-フーラノシレーションを可能にし,挑戦的な1,2-シスグリコシド結合を生成します. この方法は,様々なアルコールの受容体とフラノシルドナーを効率的に接続し,炭水化物の化学を進める.
科学分野:
- 有機化学
- 炭水化物の化学
- カタリシス
背景:
- グリコシド結合のステレオ選択的合成は,炭水化物化学において極めて重要です.
- furanosylation反応で1,2-cis置換パターンを達成することは,重要な合成課題です.
研究 の 目的:
- ステレオ選択的O-フーラノシル化反応のための新しい方法を開発する.
- これらの反応を促すために,調整されたビスチオウレア水素結合ドナー触媒を使用する.
- 高度なアノメール選択性を持つ難しい1,2-シス糖系結合にアクセスします.
主な方法:
- 精密に調整されたビスチオウレア水素結合ドナー触媒を用いる.
- アノメリックなダイアルキルフォスファート離基を持つフーラノシルドナーを使用する.
- アルコール受容体と反応します
主要な成果:
- 高度なアノメール選択性はO- フルノーシレーション反応で達成された.
- 挑戦的な1,2シス代替パターンが成功しました.
- ステレオ化学的に異なるベンジルで保護された様々なグリコシルドナーが基板として使用された.
結論:
- 立体選択的O-フーラノシル化のための新しい触媒法が確立されています.
- ビスチオウレア触媒は1,2-シス糖結合の形成を効果的に促進する.
- 機構学的研究は,触媒-ドナー複合体を含むステレオ特異的な反応経路を示している.
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