鉄複合体 bis ((ベンゼン-1,2-ディチオラト) の S,S'-協調リガンドのレドックス無無害性
Kallol Ray1, Eckhard Bill, Thomas Weyhermüller
1Max-Planck-Institute for Bioinorganic Chemistry, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany.
Journal of the American Chemical Society
|April 14, 2005
まとめ
この研究は,ディチオラートリガンドを持つ鉄複合体は高価鉄を形成しないことを明らかにしています. 代わりに,リガンドの急性モノアニオンが存在し,鉄 (III) 複合体における反鉄磁性スピン結合につながります.
科学分野:
- 無機化学 無機化学とは
- 協調化化学について
- スペクトル顕微鏡検査です.
背景:
- S,S'-協調ベンゼン-1,2-ディチオラートリガンドを含む鉄複合体は研究されている.
- 以前の研究では,高価鉄 (IV) 種の入手可能性が示唆されていた.
研究 の 目的:
- ベンゼン-1,2-ジチオラートおよびそのテルトブチル誘導体による鉄複合体の電子構造を解明する.
- 鉄の酸化状態とこれらの複合体のリガンドの性質を明らかにする.
主な方法:
- 電子吸収スペクトロスコーピーは,電子吸収スペクトロスコーピーを用います.
- 赤外線スペクトロスコーピーは,赤外線スペクトロスコーピーを用います.
- X帯電子パラマグネティック共振 (EPR) スペクトロスコピー
- モスバウアー光譜法 モスバウアー光譜法
- X線結晶グラフィーです.
主要な成果:
- 高価鉄 (IV) は,これらの鉄二酸化塩酸複合体では利用できません.
- ディチオラートリガンドのS,S'-協調系ラジカルモノアニオンが一般的です.
- 5座標 [Fe(L) ((2) ((PMe(3)) ] の電子構造は [Fe ((III) ((L) (((L)) ((*)) ((PMe ((3))) ]として記述されています.
- 三重基底状態は,鉄 (III) とリガンドラジカル間の分子内反鉄磁性スピン結合から生じる.
結論:
- ディチオラートリンガンドと鉄の化学反応には,鉄 (III) とリンガンドラジカル種が含まれているが,鉄 (IV) は含まれていない.
- 鉄の中心とリガンドラジカル間の反鉄磁気結合は,観測されたスピン状態を決定する.
- 構造的特徴は,いくつかの複合体のために提案された電子構造を確認します.
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