Kinetic and thermodynamic parameters of copper-dioxygen interaction with different oxygen binding modes
Kinetic and thermodynamic parameters of copper-dioxygen interaction with different oxygen binding modes
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DOI：
10.1016/s1381-1169(96)00250-6
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发表时间：
1997-03-14
影响因子：
--
通讯作者：
Zuberbuhler, AD
中科院分区：
文献类型：
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作者：
Karlin, KD;Tolman, WB;Zuberbuhler, AD
获得了不同结合方式的铜(I)络合物与氧作用的动力学参数和热力学参数。通常，高达80kJ摩尔(-1)的有利结合热被高达-220J K-1摩尔(-1)的强负反应熵所补偿，从而限制了总的稳定性范围。通过低温停流实验，确定了超氧和过氧络合物的顺序形成以及ETA(1)：ETA(1)和ETA(2)：ETA2MEROXO络合物的相伴形成。在几种情况下，氧的假可逆结合之后是有机配体的不可逆氧化。最近的一个结果是鉴定了ETA(2)：ETA(2)Mu-Peroxo络合物和具有断裂的O-O键的异构体双Mu-Ox化合物之间的快速平衡，这可能是几种依赖O-2的氧化还原酶的基础。
Kinetic and thermodynamic parameters for metal ion-O-2 interaction have been obtained for a variety of copper(I) complexes with different binding modes for dioxygen. In general, favorable binding enthalpies of up to 80 kJ mol(-1) are compensated by strongly negative reaction entropies up to -220 J K-1 mol(-1), restricting the range of overall stabilities. Sequential formation of superoxo and peroxo complexes, as well as concomitant formation of eta(1):eta(1) and eta(2):eta 2 mu-peroxo complexes has been established by low-temperature stopped-flow experiments. In several cases, pseudoreversible binding of dioxygen is followed by an irreversible oxidation of the organic ligand. A recent result is the identification of a rapid equilibrium between an eta(2):eta(2) mu-peroxo complex and the isomeric bis-mu-oxo compound with broken O-O bond which maybe fundamental to several O-2 dependent redox enzymes.