電子欠乏オレフィンの効率的なエポキシデーションは,カチオンのマンガン複合体によるものです
Andrew Murphy1, Geraud Dubois, T D P Stack
1Department of Chemistry, Stanford University, Stanford, California 94305, USA.
Journal of the American Chemical Society
|May 2, 2003
まとめ
新しいマンガン複合体は,最小限の触媒負荷と短い反応時間を用いて,オレフィンエポキシデーションを効率的に触媒化する. この実用的な触媒は,幅広いオレフィン基板で高収量を達成します.
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
- グリーン・ケミストリー (Green Chemistry)
背景:
- オレフィンエポキシデーションは,有機合成における重要な変換である.
- エポキシデーションのための効率的で実用的な触媒の開発は,依然として活発な研究分野です.
- 電子欠乏オレフィンは,触媒エポキシデーションに対してユニークな課題を提示します.
研究 の 目的:
- 電子欠乏オレフィンのエポキシド化のための触媒としての新しいマンガン複合体の開発と評価.
- 開発された触媒の効率,実用性,および基板の適用範囲を実証するために.
- 反応条件を最適化して,高収量と急速な変換を実現する.
主な方法:
- マンガン複合体の合成と特徴付け [MnII(R,R-mcp) ((CF3SO3) 2].
- 様々な電子欠乏オレフィンを用いた触媒エポキシデーション反応.
- 触媒の負荷,反応時間,酸化物質ステキオメトリーの最適化.
- 単一生産量を決定するために,有機化学の標準的な技術を使用して反応製品の分析.
主要な成果:
- マンガンの複合体 [MnII(R,R-mcp) ((CF3SO3) 2 ] は,オレフィンエポキシデーションのための高い触媒活性を示した.
- 効率的なエポキシデーションは,0.1 mol % の触媒負荷で達成されました.
- 酸化剤としてペラセチ酸を用いて5分以内に反応が完了しました.
- 末端,三次,シス/トランス内部オレフィン,エノン,メタクリラートを含む幅広い基質が, >85%の単離収量でエポキシジングされました.
結論:
- [MnII ((R,R-mcp)) ((CF3SO3) 2)) 複合体は,電子欠乏オレフィンのエポキシド化のための効果的で実用的な触媒である.
- 触媒は優れた効率性,広範囲の基板範囲,急速な反応速度を示しています.
- この触媒システムは,エポキシドのグリーンで効率的な合成のための貴重なツールを提供します.
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