銅の酸化添加問題に対する根本的なアプローチ:ブロモアレンのトリフローロメチル化

Chip Le¹, Tiffany Q Chen¹, Tao Liang¹

¹Merck Center for Catalysis at Princeton University, Princeton, NJ 08544, USA.

Science (New York, N.Y.)

|June 2, 2018

まとめ

銅の触媒は,アリル基を捕獲するメカニズムを使用して,効率的なアレントリフローロメチル化を克服します. この二重銅-フォトレドックス戦略は,分子合成において広範な応用を可能にします.

科学分野:

有機化学
カタリシス
合成方法論

背景:

トランジション金属触媒によるアレン機能化は分子合成に不可欠である.
銅の触媒は,還元性除去に好ましいが,ハロアレン結合における緩やかな酸化添加によって妨げられる.
既存の銅触媒プロトコルは,酸化添加段階が遅いため,制限に直面しています.

研究の目的:

銅触媒によるハロアレン結合の限界を克服し,緩やかな酸化添加に対処する.
銅触媒を用いたアレン機能化のための新しい戦略を開発する.
アリルブロミドの一般的なトリフローロメチル化を可能にします.

主な方法:

シリル根のハロゲン抽出を含むアリル根捕獲メカニズムの開発.
二重銅-フォトレドックス触媒システムの適用
オープンシェルのアリル種の形成を含むメカニズム的経路の調査.

主要な成果:

ラジカル捕捉メカニズムで緩やかな銅酸化添加を成功裏に克服しました
アリルブロミドの一般的なトリフローロメチル化を達成した.
オープンシェルのアリル中間物質の形成を支持するメカニズム的証拠を提供した.

結論:

開発されたアリル基捕獲戦略は,銅触媒における酸化添加ボトルネックを効果的に回避します.
二重の銅-フォトレドックス触媒は,アレントリフローロメチル化のための強力なアプローチを提供します.
この方法論は,複合分子合成のための銅触媒反応の範囲を拡大する.

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