Lanznaster Mauricio, Neves Ademir, Bortoluzzi Adailton J, Assumpção Aline M C, Vencato Ivo, Machado Sergio P, Drechsel Sueli M
Departamento de Química, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC, Brazil.
Inorg Chem. 2006 Feb 6;45(3):1005-11. doi: 10.1021/ic050869o.
Three new iron(III) complexes with the ligand N,N'-bis(2-hydroxybenzyl)-N,N'-bis(pyridin-2-ylmethyl)ethylenediamine, H2bbpen, containing electron-donating and -withdrawing groups (Me, Br, NO2) in the 5-position of the phenol rings were synthesized and fully characterized by IR spectroscopy, ESI mass spectrometry, and CHN elemental analyses. X-ray structures of the iron(III) complexes containing NO2 and Me groups were determined. The effects of the substituents on the electronic properties of the complexes were detected by UV-visible spectroscopy, cyclic voltammetry, and X-ray crystallography. Linear correlations between the Hammett parameter for the substituents (sigma(p)) and the Fe(III)/Fe(II) redox potentials or ligand-metal charge-transfer (LMCT) processes of the complexes were obtained. A theoretical study using DFT is presented and shows good agreement between the experimental and calculated data.
合成了三种新的铁（III）配合物，其配体为N,N'-双（2-羟基苄基）-N,N'-双（吡啶-2-基甲基）乙二胺（H2bbpen），在酚环的5-位含有供电子和吸电子基团（甲基、溴、硝基），并通过红外光谱、电喷雾电离质谱和CHN元素分析对其进行了全面表征。测定了含硝基和甲基的铁（III）配合物的X射线结构。通过紫外可见光谱、循环伏安法和X射线晶体学检测了取代基对配合物电子性质的影响。获得了取代基的哈米特参数（sigma(p)）与配合物的Fe(III)/Fe(II)氧化还原电位或配体-金属电荷转移（LMCT）过程之间的线性相关性。提出了一项使用密度泛函理论（DFT）的理论研究，结果表明实验数据与计算数据吻合良好。
