オープンシェル,カービンの橋渡しダイアイロン複合体の活性化
Charles H Arnett1, Theodor Agapie1
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
Journal of the American Chemical Society
|April 15, 2020
まとめ
研究者は窒素酸をモデル化した.
科学分野:
- バイオ有機化学
- 有機金属化学
- カタリシス
背景:
- N2結合のための窒素酵素フェモコファクターの活性化は十分に理解されていません.
- 結晶学では,N2の減少は,炭素で橋渡された二鉄部位で発生することを示唆しています.
研究 の 目的:
- N2結合のためのFe-(μ-C) -Feサイトの活性化をモデル化する.
- 新しい二核化ヘキサフォシンリガンドとその二鉄μ-カルビネ複合体を合成し,特徴づけること.
主な方法:
- ヘキサフォシンリガンドとその二鉄μ-カルビネ複合体の合成.
- SQUID磁気計,Mössbauer光譜,DFT計算を用いた特徴付け
- H+,e-,およびN2結合を含むメカニズム研究.
主要な成果:
- S = 1基底状態の独特のダイアイロンμ-カルビーン複合体 (P6ArC) Fe2 ((μ-H) が合成された.
- この複合体は,H+/e−源を加えると,N2結合に向けて活性化される.
- N2を調整できる鉄カルベンの中間物質が特定された.
結論:
- この研究は,窒素酶におけるFeMo共因子の還元活性化モデルを提供する.
- 新しいFe (μ-カルビネ) (μ-H) Feモチーフが特徴付けられました.
- 鉄の中心でのN2結合と還元のメカニズムについての洞察を得ました.
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