C ((sp2) -H 空気安定のコバルト前触媒を用いたフッ化アーレンのボリレーション:電子的に強化されたサイト選択性は合成機会を可能にします
Jennifer V Obligacion1, Máté J Bezdek1, Paul J Chirik1
1Department of Chemistry, Princeton University , New Jersey 08544, United States.
Journal of the American Chemical Society
|February 1, 2017
まとめ
新しいコバルト触媒は,フッ素化アレンのC ((sp2) -Hボリレーションで高オルト-フッ素選択性を達成する. この突破により 抗炎症薬 フルビプロフェンの 効率的な合成が可能になりました
科学分野:
- 有機金属化学
- カタリシス
- 合成有機化学
背景:
- C ((sp2) -Hボリレーションは有機合成における重要な反応である.
- フッ素化アレンのボリル化において,サイト選択性,特にオルト・トゥ・フッ素を達成することは困難である.
- 貴金属の触媒はしばしば,基板の範囲を制限する指向グループに依存します.
研究 の 目的:
- フッ素化アレンのサイト選択C ((sp2) -Hボリレーションのための新しいコバルト触媒を開発する.
- オーソとフッ素との高い選択性を達成し,従来の指向グループ効果を覆す.
- 価値ある薬品を合成する際に これらの触媒の有用性を実証する.
主な方法:
- 4-Me-iPrPNPを特徴とするコバルト (III) 二酸化ボリル (1) とコバルト (II) 二酸化ピヴァラート (2) の複合体の合成と特徴付け.
- 様々なフッ素アレンのC ((sp2) -Hボリレーションにおける触媒活性と選択性の評価.
- アミンやヒドロシランなどの他の反応剤との機能群耐性の評価
主要な成果:
- 電子的に強化されたコバルト触媒の開発は,C ((sp2) -Hボリル化において高オルト対フッ素選択性を示す.
- 空気に敏感なコバルト (III) と空気に安定したコバルト (II) の両方の触媒は,幅広い機能群の許容性を示した.
- ベンジルジメチラミンとヒドロシランの存在でも観察された選択性は維持され,貴金属触媒の性能を上回った.
- フルビプロフェンの効率的な合成に触媒システムが成功しました.
結論:
- 新しいコバルト触媒は,フッ素化アレンのC ((sp2) -Hボリル化のための電子的に強化されたサイト選択性を提供します.
- これらの触媒は,貴金属システムに強力な代替手段を提供し,制御グループに関連する制限を克服します.
- 開発された方法論は,抗炎症薬フルビプロフェンを含む重要な分子の実用的な合成を容易にする.
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