Mirzaei Masoud, Eshtiagh-Hosseini Hossein, Karrabi Zahra, Notash Behrouz
Department of Chemistry, Ferdowsi University of Mashhad, Mashhad 917751436, Iran.
Acta Crystallogr C. 2013 Oct;69(Pt 10):1140-3. doi: 10.1107/S0108270113025006. Epub 2013 Sep 28.
4-Hydroxypyridine-2,6-dicarboxylic acid (chelidamic acid, hypydc[H]H2) reacts with MnCl2·2H2O in the presence of piperazine in water to afford the title complex, {[Mn3(C7H2NO5)2(H2O)8]·3H2O}n or {[Mn3(hypydc)2(H2O)8]·3H2O}n. This compound is a one-dimensional coordination polymer, with the twofold symmetric repeat unit containing three metal centres. Two different coordination geometries are observed for the two independent Mn(II) metal centres, viz. a distorted pentagonal bipyramid and a distorted octahedron. The 4-oxidopyridine-2,6-dicarboxylate anions and two of the water molecules act as bridging ligands. The zigzag-like geometry of the coordination polymer is stabilized by hydrogen bonds. O-H···O and C-H···O hydrogen bonds and water clusters consolidate the three-dimensional network structure.
4-羟基吡啶-2,6-二羧酸（白屈氨酸，hypydc[H]H₂）在哌嗪存在下于水中与MnCl₂·2H₂O反应，得到标题配合物{[Mn₃(C₇H₂NO₅)₂(H₂O)₈]·3H₂O}ₙ或{[Mn₃(hypydc)₂(H₂O)₈]·3H₂O}ₙ。该化合物是一种一维配位聚合物，其具有包含三个金属中心的二重对称重复单元。对于两个独立的Mn(II)金属中心观察到两种不同的配位几何构型，即扭曲的五角双锥和扭曲的八面体。4-氧化吡啶-2,6-二羧酸根阴离子和两个水分子充当桥联配体。配位聚合物的锯齿状几何构型通过氢键得以稳定。O-H···O和C-H···O氢键以及水簇巩固了三维网络结构。
