水酸化のための触媒としての四角平面性ポリピリジル型リガンドの鉄複合体
Lanka D Wickramasinghe1, Rongwei Zhou1, Ruifa Zong1
1Department of Chemistry, 112 Fleming Building, University of Houston , Houston, Texas 77204-5003, United States.
Journal of the American Chemical Society
|October 2, 2015
まとめ
新型テトラデント酸リガンド,2- ((pyrid-2'-yl) -8- ((1′′,10′′-phenanthrolin-2′′-yl) -キノリン (ppq) は,効率的な水酸化を促進する. 鉄 (III) -ppq複合体は高回転頻度で酸素進化を触媒する.
科学分野:
- 協調化学
- バイオ有機化学
- カタリシス
背景:
- テトラデントートリガンドの2- ((pyrid-2'-yl) -8- ((1′′,10′′-phenanthrolin-2′′-yl) -キノリン (ppq) は,sp ((2) 炭素リンクナーを持つユニークなクアターピリジン骨格を特徴としています.
- この構造は,第一列の移行金属に適した中性,正方形の平面調整環境を生成します.
- ppq と bis-phenanthroline amine (dpa) を含む鉄複合体を合成し,特徴づけました.
研究 の 目的:
- ppq と dpa リガンドによる鉄複合体の電気化学的性質と触媒的活性を調べる.
- 単核と二核の鉄複合体の水酸化能力を比較する.
- 鉄の複合体によって催生された 酸素の進化のメカニズムを探求する
主な方法:
- ppqとdpaによる鉄 (III) 複合体の合成とX線構造分析
- 酸化ポテンシャルと電子移転プロセスを決定するための電気化学的研究.
- 酸素の進化率とターンオーバー周波数を測定するために,犠牲の酸化剤としてセリック・アンモニアム・ニートを使用する触媒実験.
主要な成果:
- Fe ((III) ((ppq) コンプレックスはμ-オクソブリッジジマーを形成し,Fe ((III) ((dpa) コンプレックスは1:1コンプレックスを形成する.
- Fe (III) (dpa) は2つの反転可能な1電子酸化波を示している.
- Fe ((III) ((ppq) は,より高い酸化状態 (Fe ((IV) Fe ((IV) からFe ((V) Fe ((III)) を示す2電子酸化過程を示し,その後のFeO種への不釣り合いを示している.
- Fe ((III) ((ppq) 複合体は,犠牲性酸化物質による酸性条件下でのFe ((III) ((dpa) 複合体 (TOF = 842 h−1) と比較して,著しく高い酸素進化活性 (TOF = 7920 h−1) を示した.
結論:
- ppqリガンドは,鉄複合体のユニークな電子特性を可能にし,マルチ電子還酸化プロセスを促進する.
- 二核Fe (III) (ppq) 複合体は,単核Fe (III) (dpa) 複合体を大幅に上回る,水酸化のための非常に効率的な触媒である.
- これらの発見は,人工光合成と水分裂アプリケーションのための高度な触媒を開発する際のカスタマイズされたリガンド設計の可能性を強調しています.
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