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Negishiのクロスカップリング反応における鉄 (I)
Christopher J Adams1, Robin B Bedford, Emma Carter
1School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK.
Journal of the American Chemical Society
|June 15, 2012
まとめ
鉄 (((I) 複合体は,ネギシ交互結合反応において極めて重要です. 研究者らは,主要な鉄 (I) の中間物質を分離し,特徴づけ,そのうち1つは,これらの重要な有機合成反応のオンサイクル触媒として有望であることを示した.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- ネギシ・クロスカップリング反応は,炭素対炭素結合の形成に不可欠である.
- これらの反応における低価鉄種の役割は,依然として研究の対象となっている.
研究 の 目的:
- ネギシ・クロスカップリング反応における鉄の重要性を示すために.
- 触媒的に活性な鉄 (I) の中間物質を分離し,特徴づけること.
主な方法:
- 新しい鉄 (I) 複合体の合成と分離: [FeX (dpbz) 2].
- X線結晶学を用いた特徴化.
- ネギシ・クロスカップリング反応における触媒活性の評価.
主要な成果:
- 異なるリガンド (4-トリル,Cl,Br) を含む鉄 (I) 複合体の分離.
- 結晶学的データは,複合体の構造を確認した.
- 複合体8b (鉄(I) ブロミド) は,オンサイクル中間物質と一致する触媒性能を示した.
- 複合体7 (鉄(I) 4-トリル) は,周期外種であるように見えた.
結論:
- 鉄はネギシ交互結合反応の触媒サイクルにおいて重要な役割を果たします.
- 単離された鉄 (I) 複合体は,反応機構の洞察を提供します.
- 特定の鉄 (I) 種は,効果的なオンサイクル触媒として作用する.
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