二酸化炭素由来非ヘム単核FeIII(OH) 複合体と炭素基との反応性
Vishal Yadav1, Jesse B Gordon1, Maxime A Siegler1
1Department of Chemistry , The Johns Hopkins University , Baltimore , Maryland 21218 , United States.
Journal of the American Chemical Society
|June 28, 2019
まとめ
研究者は,反応性のある鉄 (III) 水酸化物複合体を安定させるための新しいリガンドを合成した. この鉄の複合体は非ヘム鉄の酵素を模倣し 炭素の根源と反応し そのメカニズムに洞察を与えます
科学分野:
- バイオ有機化学
- 有機金属化学
- 協調化学
背景:
- 非ヘム鉄酵素は生物学的酸化反応において重要な役割を果たします.
- これらの酵素のメカニズムを理解することは,反応性中間物質の一時的な性質のために困難です.
- 反応性鉄の種を安定させることは,機械学的調査の鍵です.
研究 の 目的:
- 終末鉄 (III) 水酸化物複合体を安定させる新しいリガンドを合成する.
- 分子酸素と炭素ラジカルとの安定した複合体の反応性を調べる
- ノンヘム鉄酵素で提案されたラジカルリバウンドメカニズムを模倣し解明する.
主な方法:
- 新しいテトラデンタート,モノアニオン,混合N/Oドナーリガンド (BNPAPh2O-) を合成し,水素結合能力を有する.
- 鉄 (II) と鉄 (III) 複合体の特徴は,X線 difraktion,質量スペクトロメトリー,UV-vis,NMR (H,F),Mössbauer (Fe) と EPRスペクトロスコピーを用いたものである.
- O2と炭素ラジカル (Ar3C) との反応を含む反応性研究
主要な成果:
- 設計されたリガンドを用いて単核末端のFeIII(OH) コンプレックスの成功合成と安定化.
- FeII複合体はO2と反応してFeIII(OH) 種を形成する.
- FeIII(OH) 複合体は炭素基と反応し,アルコールを生成し,FeII複合体を再生し,根幹のリバウンドプロセスを反映します.
結論:
- 新しいリガンドは,反応性末端の鉄 (III) 水酸化物種を効果的に安定させる.
- 観察された反応性は,非ヘム鉄酵素触媒における根幹のリバウンドステップの化学モデルを提供します.
- この研究は,生物学的に重要な鉄媒介反応のメカニズムに関する貴重な洞察を提供します.
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