Tuning the Diiron Core Geometry in Carboxylate-Bridged Macrocyclic Model Complexes Affects Their Redox Properties and Supports Oxidation Chemistry
作者:Fang Wang、Sabine Becker、Mikael A. Minier、Andrei Loas、Megan N. Jackson、Stephen J. Lippard
DOI:10.1021/acs.inorgchem.7b01418
日期:2017.9.18
phenol-imine macrocyclic ligands (H3PIMICn). In the presence of an external bulky carboxylic acid (RCO2H), the ligands react with [Fe2(Mes)4] (Mes = 2,4,6-trimethylphenyl) to afford dinuclear [Fe2(PIMICn)(RCO2)(MeCN)] (n = 4–6) complexes. X-ray diffraction studies revealed structural similarities between these complexes and the reduced diiron active sites of proteins such as Class I ribonucleotide reductase
我们介绍了一个新的平台,通过将一个小的悬而未决的内部羧酸盐(CH 2)n COOH束缚在酚亚胺大环配体(H 3 PIMICn)上,模拟羧酸盐桥联的二价铁蛋白的配位环境。在外部大体积羧酸(RCO 2 H)的存在下,配体与[Fe 2(Mes)4 ](Mes = 2,4,6-三甲基苯基)反应,得到双核[Fe 2(PIMICn)(RCO 2)(MeCN)](n= 4–6)个复合物。X射线衍射研究表明,这些复合物与蛋白质的二铁活性位点(如I类核糖核苷酸还原酶(RNR)R2和可溶性甲烷单加氧酶羟化酶)的结构相似。内部羧酸酯臂的CH 2单元数控制着二铁核的几何形状,进而影响了配合物的阳极峰电位。作为功能性合成模型,这些络合物在存在过氧化物时促进C–H键的氧化,并从O 2到内部膦部分进行羰基转移。