The syntheses of a novel hydroxyl-functionalized tetradentate NHC/pyridine hybrid ligand and the corresponding Ag(I) and Fe(II) complexes are presented. Spectroscopic and X-ray diffraction techniques are used for structural investigations and cyclic voltammetry measurements reveal interesting electronic properties. Transmetalation of the trinuclear Ag(I) complex (C1) yields a mononuclear and a dinuclear iron(II) bis(NHC) complex (C2 and C3), which can be separated by stepwise precipitation. The former is isostructural to iron(II) bis(NHC) complex A, which is a versatile oxidation catalyst. Furthermore, suitable conditions for esterification reactions of the ligand precursor and iron(II) bis(NHC) complex (C2) have been established, demonstrating the utility of the hydroxyl functionality for immobilization and derivatization purposes.

中文翻译：

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羟基官能化的铁（ii）双（NHC）配合物的合成，表征和衍生化†

介绍了一种新型的羟基官能化的四齿NHC /吡啶杂化配体以及相应的Ag（I）和Fe（II）配合物的合成。光谱和X射线衍射技术用于结构研究，循环伏安法测量显示出令人感兴趣的电子特性。三核Ag（I）配合物（C1）的金属转移产生单核和双核铁（II）双（NHC）配合物（C2和C3），可以通过逐步沉淀法将其分离。前者与铁（II）双（NHC）配合物A同构，这是一种多功能的氧化催化剂。此外，已经建立了用于配体前体和铁（II）双（NHC）络合物（C2）的酯化反应的合适条件，证明了羟基官能团用于固定化和衍生化的效用。