アルキルボロン反応剤を用いたアリルカルボキシル酸のリガンド加速度オーソ-C-Hアルキル化
Peter S Thuy-Boun1, Giorgio Villa, Devin Dang
1Department of Chemistry, The Scripps Research Institute , 10550 N. Torrey Pines Road, La Jolla, California 92037, United States.
Journal of the American Chemical Society
|October 16, 2013
まとめ
この研究では,パラジウム触媒とアルキルボロン反応剤を用いたフェニラセチウム酸とベンゾ酸のオーソアルキル化のための新しい方法が紹介されています. モノプロテクトアミノ酸リガンドは,C-H機能化のための反応効率を高めます.
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
- 合成方法論 合成方法論
背景:
- パラジウムによって触媒化されたC-H機能化は,有機合成の強力なツールです.
- カーボキシル酸の直接アルキル化は,合成の課題であり続けています.
- C-H結合活性化のための効率的な触媒システムの開発は極めて重要です.
研究 の 目的:
- フェニル酸とベンゾ酸のパラジウム ((II) -触媒化されたオルトC-Hアルキル化のための新しいプロトコルを開発する.
- アルキルボロン反応剤のアルキル化剤としての有用性を調査する.
- モノプロテクトアミノ酸リガンドが反応性を促進する役割を調査する.
主な方法:
- C-H活性化のためのパラジウム (II) 触媒を使用した.
- アルキルボロン反応剤,アルキルトリフローロボラートカリウム,アルキルボロン酸を含むアルキルボロン反応剤を使用.
- 触媒活性を増強するために,単一保護アミノ酸リガンド (MPAA) の使用を調査した.
主要な成果:
- フェニル酸とベンゾ酸のPd(II) 触媒によるオーソ-C-Hアルキル化のための成功したプロトコルが確立されました.
- モノプロテクトアミノ酸リガンドは,反応速度と生産性を著しく改善しました.
- カリウムアルキルトリフッ素ボラートとアルキルボロン酸は,両方が結合パートナーとして互換性を示した.
結論:
- 開発されたプロトコルは,オルトアルキル化されたカルボキシル酸の合成のための効率的な経路を提供します.
- MPAAリガンドは,パラジウム触媒によるC-Hアルキル化反応を促進するのに有効です.
- この研究は,容易に入手可能なアルキルボロン反応剤を使用して,C-H機能化のための貴重な方法を提供します.
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