五座標鉄ポルフィリンカルベンの複合体の電子構成とリガンド性質:実験的研究
Yulong Liu1, Wei Xu2, Jing Zhang2
1College of Materials Science and Optoelectronic Technology, University of Chinese Academy of Sciences , Yanqi Lake, Huairou District, Beijing 101408, China.
Journal of the American Chemical Society
|March 25, 2017
まとめ
鉄カルベンポルフィリン複合体は,低スピン鉄 (II) の構成を示し,モースバウアー光譜で確認した. これらの研究は,カルベンリガンドの共性性質を明らかにし,同位体シフトと軸性結合距離の間の相関を確立する.
科学分野:
- 有機金属化学
- 協調化学
- スペクトロスコーピー
背景:
- 鉄ポルフィリン複合体は,様々な化学的および生物学的プロセスにおいて不可欠である.
- これらの複合体の電子構造と結合を理解することは その反応性の鍵です
- カーベンのリガンドは,金属の中心とのユニークな結合相互作用を提供します.
研究 の 目的:
- 新しい5座標の鉄ポルフィリンカルベンの複合体を合成し,特徴づけること.
- 鉄の中心の電子構成と酸化状態を明らかにする.
- 金属-カルベンの結合の性質とその構造的影響を調査する.
主な方法:
- 構造を決定するための単一結晶X線 difraktion.
- 鉄の酸化状態を決定するX線吸収近辺スペクトロスコーピー (XANES).
- 電子構成と結合を検知するために,モースバウアー光譜法 (多温度,高磁場) を用いる.
- 核磁共振 (NMR) と,補完的な特徴づけのための紫外線スペクトロスコーピー.
主要な成果:
- CCl2およびCPh2リガンドを持つ合成鉄 (II) ポルフィリンカルベンの複合体.
- XANESは鉄の酸化状態を確認した.
- モッズバウアー光譜は,大きな四極分裂を持つ低スピン (S=0) の電子構成を明らかにした.
- 構造とMössbauerのデータは,鉄-カルベンの結合の共価性を示した.
- 鉄同位体シフトとカーベンリガンドの軸結合距離との新しい相関を確立した.
結論:
- 調査された鉄カルベンのポルフィリン複合体は,低スピンの鉄 (II) 種として存在します.
- カーベンのリガンドは,鉄の中心と共性結合を形成し,電子構造に影響を与えます.
- 鉄炭酸塩複合体における同位体シフトと結合距離に関する新しい構造-性質関係が特定された.
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