塩基に敏感なボロン酸による"カチオン"スズキ-ミヤウラ結合
Liye Chen1, Daniel R Sanchez1, Bufan Zhang1
1Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|September 2, 2017
まとめ
この研究では,新しい塩基なしのスズキ-ミヤウラ結合 (SMC) 方法が導入されています. この進歩により,過敏なポリフルオアリル化合物を含め,温和な条件下で効率的な結合が可能になります.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- ボロン酸,特にポリフルオアリルとヘテロアリルのプロトデボロネーションは,スズキ-ミヤウラ結合 (SMC) で一般的な問題である.
- 伝統的なSMCは塩基を必要とし,これは敏感な基板との望ましくない副作用につながる可能性があります.
- 複雑な分子に対するSMCの範囲を広げるには,塩基のない方法が必要です.
研究 の 目的:
- 新しい塩基のないスズキ・ミヤウラ結合 (SMC) 方法を開発する.
- 敏感なボロン酸,特にポリフルオアリルとヘテロアリル基板の結合を可能にします.
- この新しいSMCアプローチのメカニズムを調査する.
主な方法:
- PAd3-Pd触媒を用いた"カチオン性"SMCプロトコルの開発
- 塩基や金属メディエーターなしで室温 (rt) で進行する反応最適化.
- 反応中間物質を明らかにするためのステキオメトリック実験.
主要な成果:
- 室温のPAd3-Pd触媒で成功した塩基のないSMC.
- ポリフルオアリルおよびヘテロアリル化合物を含む幅広い敏感なボロン酸がクリーンに結合されました.
- オーガノパラジウムカチオンの介介介性を支持する証拠が得られた.
結論:
- 新しい塩基のないカチオン型SMC法が確立された.
- この方法は,塩基促進プロトデボレーションに関連する制限を克服します.
- この発見は,SMCにおける伝達のためのカチオンの経路を支持し,メカニズムの理解を進める.
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