ステレオ特異性アリル機能化:アリルボロナート複合体の反応と電ophiles
Cristina García-Ruiz1, Jack L-Y Chen1, Christopher Sandford1
1School of Chemistry, University of Bristol , Cantock's Close, Bristol BS8 1TS, United Kingdom.
Journal of the American Chemical Society
|October 14, 2017
まとめ
アリルリチウムによって活性化されるアルリボラネート複合体は,多様な電ophilesに対する非常に強化された反応性を示します. 新しい機能とステレオセンターを備えた複雑な分子の 効率的な合成を可能にします
科学分野:
- 有機金属化学
- 合成有機化学
背景:
- アリルボロンエステルは,主にカルボニルとイミンと反応する,既知のヌクレオフィルである.
- 彼らの反応性は,より広い範囲の電愛性種に限られています.
研究 の 目的:
- アリルボロンエステルの核愛性を高めるため
- アリルボロン反応剤と反応する電ophilesの範囲を拡大する.
- 高ステレオ制御で機能化された分子を合成するための新しい方法を開発する.
主な方法:
- アリルリチウム反応剤を用いたアルリルボロンエステルの活性化により,アルリルボラネット複合体を形成する.
- トロピリウム,ベンゾディチオリウム,活性化ピリジン,エシェンモッサー塩,トグニの反応剤,セレクトフローア,ダイソプロピルアゾジカルボキシラート (DIAD),およびMeSXを含む様々な電化物との反応.
- 地域とステレオ化学的結果に対する反応産物の分析
主要な成果:
- アリルボロナート複合体は,原産ボロンエステルよりも7~10倍の核好性を有意に示した.
- 高いレジオとステレオ制御により,幅広い電化器材への追加が成功しました.
- このプロトコルは,フッ素とトリフローロメチル基を持つ四次性ステレオセンターを含む新しい機能へのアクセスを提供します.
結論:
- アリルチウム媒介の活性化により,アリルボロンエステルの反応性が劇的に増加する.
- この方法は,複雑な有機分子をステレオ選択的に合成するための多用途で強力なアプローチを提供します.
- 開発されたプロトコルは,有機化学におけるアルリボロン反応剤の合成有用性を拡大する.
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