ポルフィリンのような性質を持つ非ヘム鉄 (III) 複合体で,非対称なエポキシデーションを触媒化する
Takashi Niwa1, Masahisa Nakada
1Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Ohkubo, Tokyo, 169-8555, Japan. niw@aoni.waseda.jp
Journal of the American Chemical Society
|August 7, 2012
まとめ
カーバゾールリガンドを含む新しい鉄 (III) 複合体は,アルケンの高度にエナチオセレクティブな非対称なエポキシデーションを達成します. この非ヘム系触媒は,室温で効率的に動作し,鉄のポルフィリンを模倣する.
科学分野:
- 有機金属化学 有機金属化学
- アシンメトリック・カタリシス
- 合成有機化学 合成有機化学について
背景:
- 鉄複合体は,有機合成における重要な触媒である.
- 非ヘム鉄触媒は,ポルフィリンベースのシステムに代替品を提供します.
- 非対称なエポキシデーションは,キラル構造ブロックの生産に不可欠です.
研究 の 目的:
- 非対称なエポキシデーションのための新しい鉄 (III) 複合体を開発する.
- 新しい複合体の触媒活性と選択性を調査する.
- 鉄ポルフィリンと非ヘム鉄複合体の電子構造を比較する.
主な方法:
- カーバゾール基のトリデント酸リガンドの合成.
- 鉄 (III) 複合体の形成と特徴.
- 鉄 (III) 触媒を用いた (E) -アルケンの非対称エポキシデーション.
主要な成果:
- 鉄 (III) 複合体は, (E) -アルケンの非対称なエポキシデーションを効果的に触媒化した.
- 高いエナチオセレクティブ性は,室温で達成されました.
- 複合体は5座標のトライゴナル・バイピラミッド形構造を示しています.
- 酸化状態は,鉄のポルフィリンと電子的な類似性を共有しています.
結論:
- 開発された鉄 (III) 複合体は,エナチオセレクティブ・アシンメトリックエポキシデーションの強力な触媒である.
- この非ヘム触媒は,キラル合成のための有望な代替手段を提供します.
- この研究は,非ヘム鉄触媒の理解を前進させる.
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