鉄のポルフィルノゲンのマルチエレクトロン・レドックス化学

Julien Bachmann¹, Daniel G Nocera

¹Department of Chemistry, 6-335, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139-4207, USA.

Journal of the American Chemical Society

|March 31, 2005

まとめ

鉄のポルファイリノゲンは,金属・マクロサイクル協力により,ユニークなマルチ電子・レドックス化学を現しています. リガンドの酸化によって引き起こされるこの行動は,ヘムコファクターと著しく異なる.

科学分野:

無機化学無機化学とは
バイオ・オーガニック化学バイオ・オーガニック化学
マテリアルサイエンス材料科学

背景:

鉄のポルフィリノゲンは,触媒と医学における潜在的な応用を持つマクロサイクル化合物です.
酸化還元性特性を理解することは,新しい鉄ベースの機能材料の設計に不可欠です.
ヘム共因子には,関連性があるが,明確な酸化還元制限がある.

研究の目的:

様々な酸化状態にある鉄オクタメチルポルフィルニノゲンの構造的特徴を特定する.
これらの化合物の鉄およびリガンドベースのリドックス化学を定義する.
鉄のポルファイリノゲンにおける金属マクロサイクル協同性を探求する.

主な方法:

鉄オクタメチルポルフィルノゲンの合成と構造的特徴.
レドックスポテンシャル (E(1/2) とE(p)) を決定するための電気化学的研究.
電子パラマグネティック共振 (EPR),磁気,モスバウアー光譜.
密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.

主要な成果:

鉄のポルフィリノゲンは,3つの酸化状態で特徴づけられました.
鉄の中心酸化は容易に行われる (E(1/2) = -0.57 V),リガンドは4電子酸化 (E(p) = +0.77 V) を受ける.
酸化等価はスピロサイクロプロパン環に貯蔵され,鉄のスピン状態 (中位から高スピン) に影響します.

結論:

独特の金属マクロサイクル協同性は,鉄のポルフィリノゲンでマルチエレクトロン・レドックス化学を可能にする.
この化学反応は,ヘム共因子で観察されたものとは異なる.
鉄のポルフィリノゲンは,新しい鉄ベースの機能的システムを開発するための汎用的なプラットフォームを提供します.

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