低スピンのd5鉄イミド:低座標鉄によるニトロンの捕獲によって,4座標のFe (III) 複合体[PhB (CH2PPh2) ]Fe=N-p-tolylを生成する
Steven D Brown1, Theodore A Betley, Jonas C Peters
1Division of Chemistry and Chemical Engineering, Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|January 9, 2003
まとめ
研究者らは,希少な擬四面体鉄 (I) 複合体[PhBP3]Fe (PPh3) を合成し,酸化して最初の単核鉄 (III) イミド[PhBP3]FeNAr.Arを形成した. このイミドはさらに一酸化炭素と反応し,ダイカルボニル種を生成する.
科学分野:
- 有機金属化学 有機金属化学
- 鉄の複合体 鉄の複合体
- 協調化化学について
背景:
- 低価鉄複合体の合成と特徴づけは,鉄の反応性を理解するために重要である.
- 単核鉄イミド複合体は希少で,それらの電子構造は著しい関心を持っている.
- アジドと一酸化炭素との鉄複合体の反応性は,触媒と合成において不可欠である.
研究 の 目的:
- [PhBP3]リガンドを含む新種の擬似四面体鉄 (pseudotetrahedral iron) 複合体を合成し,特徴づけること.
- 鉄 (((I) 複合体の酸化をアリルアジドで鉄イミドを形成する過程を研究する.
- 結成された鉄 (III) イミドと一酸化炭素の反応性を調べる.
主な方法:
- [PhBP3]Fe(PPh3) 複合体の合成について
- アリルアジドとの酸化反応により,鉄イミド複合体 [PhBP3]FeNAr.Ar.を形成する.
- 鉄イミドと一酸化炭素の反応により[PhBP3]Fe(CO) 2.
主要な成果:
- S = 3/2基底状態の希少な擬似四面体鉄 (I) 複合体[PhBP3]Fe (PPh3) が合成されました.
- 鉄 (I) 複合体は,アリルアジドによって急速に酸化され,d5鉄 (III) イミド [PhBP3]FeNAr.を生成した.
- Fe(III) イミドは低スピンで,最初の単核鉄イミドであり,COと反応してイソシアネートと[PhBP3]Fe(CO) 2.
結論:
- この研究は,ユニークな鉄 (I) 複合体の合成に成功し,その後に最初の単核鉄 (III) イミドに変換されたことを報告しています.
- 鉄イミドとCOの反応性は,イソシアネート放出と二カルボニル種の形成のための新しい経路を示しています.
- この発見は,鉄の協調化学の理解と,新しい鉄-窒素,鉄-炭素結合の合成の理解を広げています.
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