水素結合相移転触媒による非対称な核性フッ素化
Gabriele Pupo1, Francesco Ibba1, David M H Ascough1
1University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, UK.
Science (New York, N.Y.)
|May 12, 2018
まとめ
不溶性無機塩は,エナチオ選択的触媒で用いられるようになった. 新しい方法は水素結合と相移転触媒を融合させ,これらの核愛素を活性化させ,非対称合成を可能にします.
科学分野:
- 有機化学
- カタリシス
- 非対称合成
背景:
- 無機塩からのアニオン系ヌクレオフィルは,通常,有機溶剤に溶けないため,エナチオ選択的触媒の利用を制限する.
- 合成方法の拡大には これらの挑戦的な核愛体を活性化できる 触媒システムの開発が不可欠です
研究 の 目的:
- 不溶性アニオンヌクレオフィルを用いたエナンチオセレクティブ反応のための新しい触媒システムを開発する.
- 水素結合と相移転触媒によるフッ素アニオンの活性化を証明する.
主な方法:
- クイラルビス尿素触媒を用いて,フッ素イオンとトリデント酸水素結合複合体を形成する.
- 活性化された核愛者と基板の間の反応を促進するために,相移転触媒を使用します.
- この触媒システムを用いてエピスルフォニウムイオンのエナンチオセレクティブリング開封を調査する.
主要な成果:
- セシウムフッ素を用いて,エピスルフォニウムイオンの高効率のエナンチオセレクティブリング開封を達成した.
- 水素結合複合により,不溶性ヌクレオフィルが有機介質で溶解し,反応することが示された.
- 以前の溶解性の制限を克服し,エナンチオセレクティブフッ化のための新しいプロトコルを確立しました.
結論:
- 水素結合と相移転触媒を融合させることは,不溶性アニオンヌクレオフィルを活性化するための効果的な戦略である.
- このアプローチにより,高効率のエナチオ選択的変換,例えば化が可能になる.
- 開発された方法は,合成的に価値のある代替手段を提供し,触媒化における多様なアニオン核性分子に対するより広範な適用可能性を示唆する.
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