金属触媒によるC-HとC-O機能化を統合して,アレーンアシレーションでステリック制御された地域選択性を達成する
Nicholas A Serratore1, Constance B Anderson1, Grant B Frost1
1Department of Chemistry , University of Minnesota-Twin Cities , 207 Pleasant Street SE , Minneapolis , Minnesota 55455 , United States.
Journal of the American Chemical Society
|July 11, 2018
まとめ
この研究は,リジオセレクティブアレンアシレーションのための新しいイリジウム触媒反応をサリシラートエステルを用いて導入している. この方法は,ステリック制御されたC-C結合形成を達成し,価値あるベンゾフェノン誘導体を合成するために従来の電気的芳香的置換の代替案を提供します.
科学分野:
- 有機金属化学
- 合成有機化学
- カタリシス
背景:
- C-H,C-C,C-O,C-N結合の直接的機能化は,有機金属化学の重要な目標である.
- フリデル・クラフトスアシレーションによる電気性芳香置換 (EAS) は,アリルケトン合成の一般的な方法であるが,電子制御された地域選択性によって制限されている.
- 従来の方法とは対照的な反応選択性を達成することは,重要な合成課題です.
研究 の 目的:
- サリシラートエステルを用いたステリック制御の地域選択性アセラ法を開発する.
- 様々な化学物質の重要な構造モチーフである 明らかに置換されたベンゾフェノンを合成する
- イリジウムによって触媒化されたC-OとC-Hの活性化を含む新しい反応機構を探求する.
主な方法:
- イリジウム触媒によるサリシラートエステルによる直接アシレーション.
- 単一のイリジウム触媒を用いたC-OとC-H結合活性化の統合
- 反応メカニズムの解明のための実験的および計算的研究.
主要な成果:
- ベンゾフェノンのステリック制御地域選択合成の成功
- 外部酸化物質や塩基なしでC-OとC-Hの活性化を含むユニークな触媒サイクルの実証.
- アレンとエステル成分の両方の合成範囲の広範な調査.
- 抗がん剤ヒドロキシフェンスタチンの簡潔な合成
結論:
- ステリック制御された地域選択性アレンアサイレーションのための新しい効率的なイリジウム触媒法が確立されています.
- 反応は,シネジスティックなC-OとC-Hの活性化を含むユニークなメカニズムを通して進みます.
- この方法論は,代替ベンゾフェノンおよび関連化合物を合成するための伝統的なEASの価値ある代替手段を提供します.
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