Effect of Cyanide Ligands on the Electronic Structure of [FeFe] Hydrogenase Active-Site Model Complexes with an Azadithiolate Cofactor
作者:Özlen F. Erdem、Matthias Stein、Sandeep Kaur-Ghumaan、Edward J. Reijerse、Sascha Ott、Wolfgang Lubitz
DOI:10.1002/chem.201302467
日期:2013.10.18
characterization of a close synthetic model of the [2 Fe]H subcluster in the [FeFe] hydrogenase active site is presented. It contains the full primary coordination sphere of the CO‐inhibited oxidized state of the enzyme including the CN− ligands and the azadithiolate (adt) bridge, [((μ‐SCH2)2NR)Fe2(CO)4(CN)2]2−, R=CH2CH2SCH3. The electronic structure of the model complex in its FeIFeII state was investigated
提出了[FeFe]氢化酶活性位点[2 Fe] H亚簇的紧密合成模型的详细表征。它包含的酶包括CN的CO-抑制氧化状态的全部主配位球-配体和azadithiolate(ADT)桥,[((μ-S CH 2)2 NR)的Fe 2(CO)4( CN)2 ] 2−,R = CH 2 CH 2 SCH 3。Fe I Fe II中的模型配合物的电子结构通过密度泛函理论(DFT)计算和傅里叶变换红外(FTIR)光谱研究了碳纳米管的状态。通过结合使用连续波(CW)电子顺磁共振(EPR)和超精细子级相关性(HYSCORE)实验以及DFT计算,可以证明,对于这种复合物,自旋密度在两个铁原子上都被局域化了。有趣的是,我们发现,氮气的超精细耦合,它代表了不成对电子,并在二硫醇桥氮之间的相互作用,是在将CN的类似复杂稍大于-配体用Pme代替3配体。这表明,首先,将CN - / PME 3与铁核配位的配体在adt桥中电子偶联到胺上。其次,CN