Synthesis and characterization of an iron(III) complex of an ethylenediamine derivative of an aminophenol ligand in relevance to catechol dioxygenase active site

다국어 초록 (Multilingual Abstract)

<P>An ethylene diamine derivative of a bis(phenol)diamine ligand (H2L) was synthesized via the Mannich reaction and subsequent ring cleavage of the produced imidazoline ring (H2LIm), and then it was characterized by H-1 NMR and IR spectroscopies and CHN analysis. The iron(III) complex (FeLCI) of this ligand was synthesized and characterized by IR, UV-Vis, X-ray and magnetic susceptibility studies. X-ray analysis reveals that in FeLCl the iron(III) center has a distorted square pyramidal coordination sphere and is surrounded by a chlorine atom, two amine nitrogen and two phenolate oxygen atoms of the ligand. Variable-temperature magnetic susceptibility measurements indicate that FeLCI is a paramagnetic high spin iron(III) complex. It shows weak antiferromagnetic interactions through N-H center dot center dot center dot Cl intermolecular interactions. The ligand-centered electrochemical oxidation of this complex, due to the oxidation of phenolate group to phenoxyl radicals, as well as the electrochemical metal-centered reduction of the ferric ion to the ferrous ion were investigated. In addition, the efficient cleavage by oxygenation of 3,5-di-tertbutyl-catechol with FeLCI in the presence of dioxygen was observed. (C) 2016 Elsevier Ltd. All rights reserved.</P>