ヘム・カルボニル:nu ((C-O) とFe-C/C-O結合長相関に対する環境影響
Nathan J Silvernail1, Arne Roth, Charles E Schulz
1Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
Journal of the American Chemical Society
|October 13, 2005
まとめ
この研究では,4つの鉄 (II) テトラフェニルポルフィリナートカルボニル複合体について報告しています. 一酸化炭素 (CO) の伸縮周波数の固体状態の変動は,構造的相互作用と関連しており,パイバックボンドモデルと相関しています.
科学分野:
- 有機金属化学 有機金属化学
- 協調化化学について
- スペクトル顕微鏡検査です.
背景:
- 鉄のポルフィリナートは生物学的システムにおいて極めて重要であり,しばしば一酸化炭素 (CO) の結合を伴う.
- これらの複合体におけるCO相互作用の理解は,ミオグルビンなどのヘムタンパク質の研究に情報を提供する.
研究 の 目的:
- 4つの低スピン鉄 (((II) テトラフェニルポルフィリナートカルボニル複合体を合成し,特徴づけること.
- 溶液と固体状態における一酸化炭素 (CO) の伸縮周波数に影響を与える要因を調査する.
- Fe-C-OとN(Im) -Fe-COユニットの構造-スペクトロスコピーの相関を確立する.
主な方法:
- 4つの異なる鉄 (((II) テトラフェニルポルフィリナートカルボニル複合体の合成.
- 赤外線 (IR) スペクトロスコーピーを用いて,COの伸縮周波数 (nu(C-O)) を決定する特徴付け.
- 複合体の固体構造を正確に決定するためのX線結晶学.
主要な成果:
- 複合体は,溶液中の類似のヌー・C・O値を示したが,固体状態では幅広い範囲を示した (1926年−1968年).
- 固体状態の変動は分子間CO相互作用に起因し,結晶構造分析によって確認された.
- 濃度のC-O値とFe-C/C-O結合距離の間には強い相関がみられ,パイバックボンドモデルが支持された.
結論:
- 固体相互作用は,鉄ポルフィリナート複合体におけるCOの伸縮周波数に大きな影響を与える.
- 構造的およびスペクトル学的データは,パイのバックボンドモデルに堅固な相関関係を提供します.
- 発見は,ヘムタンパク質とカルボニルミオグロビン (MbCO) のCO結合に関する洞察を提供します.
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