Pd触媒によるアミナ化反応の非常に活性な触媒である:アリルメシラートを用いたクロスカップリング反応と,アリル塩化物を用いたプライマリアミンの高度選択的モノアリレーション
Brett P Fors1, Donald A Watson, Mark R Biscoe
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|September 19, 2008
まとめ
新しいビアリルモノフォスフィンのリガンドであるBrettPhosは,アリルメシラートを使用して効率的なC-Nクロスカップリング反応を可能にします. この触媒系は,低触媒負荷でアミンやアニリン,さらにはメチラミンさえも選択的単離化を実現します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- 有機金属化学 有機金属化学
背景:
- C-Nクロスカップリング反応は,有機合成において根本的な役割を果たします.
- 選択的なアミンアリレーションのための効率的な触媒の開発は,依然として課題です.
- アリルメシラートは,他の電化分子と比較して,反応性が低い結合パートナーです.
研究 の 目的:
- C-Nクロスカップリングのためのビアリルモノフォスフィンリガンド (BrettPhos) をベースにした新しい触媒システムを報告する.
- C-N結合形成における結合パートナーとしてのアリルメシラートの有用性を実証する.
- プライマリアリファティックアミンとアニリンを高度に選択的にモノアリレーションする.
主な方法:
- ブレットフォスのリガンドの合成と特徴付け.
- BrettPhos.を使用したパラジウム触媒化されたC-Nクロスカップリング反応.
- 反応動力学と選択性の調査.
- 酸化添加複合体の構造分析.
主要な成果:
- BrettPhosベースの触媒システムは,C-Nクロスカップリングで優れた反応性を示しています.
- アリルメシラートは,電愛性パートナーとして成功裏に採用されています.
- プライマリアリファチアミンおよびアニリン単離化の高い選択性が得られた.
- メチラミンの最初の報告されたモノアリレーションが達成されました.
- 触媒の負荷が低く,反応時間が速いことが観察されました.
結論:
- BrettPhosは,パラジウム触媒によるC-Nクロスカップリング反応の非常に効果的なリガンドです.
- 触媒システムは,C-N結合形成反応の範囲を拡大して,アリルメシラートを含む.
- リガンドは,挑戦的なアミン基板の選択的モノアリレーションを可能にします.
- 酸化添加複合体の理解は,触媒の高反応性に対する機械的洞察を提供します.
さらに関連する動画
関連する概念動画
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