キラルビフェノールによって触媒化された非対称ペタシス反応
1Department of Chemistry, Center for Chemical Methodology and Library Development, Boston University, 24 Cummington Street, Boston, Massachusetts 02215, USA.
Journal of the American Chemical Society
|May 8, 2008
まとめ
(S) -VAPOLのようなキラルビフェノールは,ペタシス反応を効果的に触媒化し,貴重なキラルアルファ-アミノエステルを生成します. このエナチオセレクティブ合成は,高い生産率と優れたステレオ化学的制御を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- アシンメトリック・カタリシス
背景:
- ペタシス反応は,ボロン酸,アミン,アルデヒドを含む多成分反応である.
- この反応のためのエナチオセレクティブの方法の開発は,キラル分子を合成するために非常に重要です.
研究 の 目的:
- エナチオセレクティブペタシス反応の触媒としてキラルビフェノールの使用を調査する.
- 反応機構を調査し,高収量およびエナチオ選択性のための条件を最適化します.
主な方法:
- (S) -VAPOL (キラルビフェノール) を触媒 (15mol%) として使用しています.
- アルケニルボロナート,二次アミン,エチルグリオキシ酸塩を反応剤として利用する.
- 3 Å 分子シートを添加物として使用する.
主要な成果:
- キラルアルファ-アミノエステル製品の良好から優れた (71-92%) 収量を達成しました.
- 89:11 から 98:2 の範囲で,高いエナティオメール比を得ました.
- 機械学的研究は,単一リガンド交換とテトラコーディネートボロナート中間物質を示唆した.
結論:
- チラルビフェノールは,エナチオセレクティブペタシス反応の効果的な触媒である.
- 開発された方法は,高いステレオ化学的純度を持つキラルアルファ-アミノエステルを合成するための信頼できる経路を提供します.
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