高スピン鉄イミド複合体は,C−H結合アミネーションに適しています
Matthew J T Wilding1, Diana A Iovan1, Theodore A Betley1
1Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|August 5, 2017
まとめ
この研究は,多用途のシントンとして新しい鉄 (I) 複合体を導入します. アジドと反応して,高スピンの鉄イミド複合体を形成し,C-H結合機能化とアミネーション反応を可能にします.
科学分野:
- 無機化学
- 有機金属化学
- カタリシス
背景:
- 鉄複合体は,触媒と合成化学において極めて重要です.
- 独特の電子特性を有する低スピン鉄 (I) シントンは価値があります.
- C−H機能化のための新しい鉄複合体の開発は,活発な研究分野である.
研究 の 目的:
- 新しい低スピン鉄の複合体を合成し,特徴づけること.
- 鉄 (I) 複合体と有機アジドの反応性を調査する.
- 鉄イミド複合体のC−H結合機能化の可能性を調査する.
主な方法:
- (ArL) FeClから低スピンの鉄 (ArL) 複合体の合成.
- (ArL) Feとアダマンチルアジドとメシチルアジドの反応により,鉄イミド複合体が形成される.
- EPR,モースバウアー光譜法,磁気計,X線微分を用いた特徴付け
- C-H アミネーションメカニズムを明らかにするための運動研究 (kH/kD).
主要な成果:
- 分子内 η6-アレン相互作用を特徴とする低スピン鉄 (ArL) 複合体を合成した.
- アジドで処理すると,高スピン,三座標の鉄イミド複合体, (ArL) Fe (NAd) と (ArL) Fe (NMes) が得られた.
- これらの鉄イミド複合体は,テトラジド形成,窒素移転,H原子抽出,およびトロウエンの分子間C-Hアミネーションを含む反応性を示した.
結論:
- 合成された鉄 (I) 複合体は,反応性鉄イミド種を生成するための効果的な前駆体として機能する.
- 高スピンの鉄イミド複合体は,特にC−H結合の機能化において,多様な反応性を示す.
- 最大エネルギーと軌道重複を含む2段階のメカニズムがC−Hアミネーション反応性のために提案されている.
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