グリニャード由来ボロン"アテ"複合体とC ((sp2) ハリドまたはトリフラット間のPd触媒結合クロスカップリング:グリニャードアクティベーターおよびハリドスキャベンジャーとしてのNaOTf
Gabriel J Lovinger1, Mark D Aparece1, James P Morken1
1Department of Chemistry, Merkert Chemistry Center, Boston College , Chestnut Hill, Massachusetts 02467, United States.
Journal of the American Chemical Society
|February 7, 2017
まとめ
この研究は,触媒エナチオセレクティブクロスカップリングでグリナード反応剤を使用してキラルオルガノボロンエステルを生成するための効率的な方法を導入しています. トリフラートナトリウムは,反応を可能にし,触媒の阻害を防ぐ上で重要な役割を果たします.
科学分野:
- 有機化学
- キャタリシス
- 合成方法論
背景:
- グリナード反応剤は多用途の有機金属化合物である.
- 酵素選択合成は医薬品にとって極めて重要です
- オーガノボロンエステルは有価な合成中間物質である.
研究 の 目的:
- 新しい触媒エナチオセレクティブ結合クロスカップリング反応を開発する.
- この変換でグリナード反応剤を使用します.
- 非血性キラルオルガンボロンエステルを効率的に合成する.
主な方法:
- 触媒エナチオセレクティブ結合クロスカップリングでグリナード反応剤を使用する.
- 塩酸ナトリウムを主要添加物として使用する.
- 効率と選択性のために反応条件を最適化します.
主要な成果:
- 様々な非血性キラル・オルガノボロンエステルの合成に成功した.
- 高い収穫量と優れたエナチオ選択性が得られた.
- 反応を促進するナトリウムトライフラートの二重な役割が示された.
結論:
- 開発された方法は,キラルなオーガノボロンエステルへの効率的な経路を提供します.
- トリフラートナトリウムは"食"複合体の形成とハライド阻害などの課題を克服するために不可欠です.
- この方法論は非対称合成のためのツールキットを拡張します.
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