O2の銅媒介還元における三核中間体:銅3基から4個の電子を得ている

A P Cole¹, D E Root, P Mukherjee

¹Department of Chemistry, Stanford University, Stanford, CA 94305, USA.

Science (New York, N.Y.)

|September 27, 1996

まとめ

研究者は,O2結合分裂を示す新しい三核銅クラスタを合成しました. 三価状態の銅を特徴とするこの混合バレンスの複合体は,マルチコッパーオキシダースにおけるダイオキシゲン還元機構の洞察を提供します.

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:

金属-リガンド複合体は通常,酸素 (O2) と単純なステキオメトリック比率 (1:1, 2:1,または 4:1 金属:O2) で反応する.
金属複合体によるO2の活性化と変換を理解することは,触媒と生物学的プロセスにとって極めて重要です.
マルチコッパー酸化酵素は,O2の減少のために三核活性部位を使用しますが,正確なメカニズムはまだ調査中です.

研究の目的:

分散の3:1の金属:O2 adduct.を合成し,構造的に特徴づけるために.
混合バレンスの三核銅集群のO2結合分裂能力を調査する.
この新しい銅複合体の構造的,スペクトロスコープ的,および酸化還元性特性を調査する.

主な方法:

混合バレンスの三核銅クラスタの合成.
構造の特徴化のためのX線結晶学.
特性分析のためのスペクトル検査技術 (例えば,UV-Vis,EPR) と電気化学的方法.

主要な成果:

分離的で構造的に特徴づけられた3:1 (金属:O2) 製品が成功裏に分離されました.
三核銅集群には,三価酸化状態の銅が含まれています.
複合体はO2結合分裂を証明し,ユニークな構造,スペクトル,および酸化還元特性を示しています.

結論:

この研究は,希少な 3:1 の金属:O2 アドクトを提示し,従来の反応ステキオメトリーに挑戦しています.
混合バレンスの三核銅クラスタは,O2活性化を研究するためのモデルシステムを提供します.
この発見は,マルチコッパー酸化酵素の三核活性部位におけるO2減少のメカニズムを理解するために重要である.

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