Versatile coordination behaviour of a multi-dentate Schiff base with manganese(II), copper(II) and zinc(II) ions and their corrosion inhibition study
Versatile coordination behaviour of a multi-dentate Schiff base with manganese(II), copper(II) and zinc(II) ions and their corrosion inhibition study
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DOI：
10.1016/j.ica.2014.10.026
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发表时间：
2015-01
影响因子：
2.8
通讯作者：
Monika Mishra;Karishma Tiwari;A. Singh;V. Singh
中科院分区：
文献类型：
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作者：
Monika Mishra;Karishma Tiwari;A. Singh;V. Singh
合成了席夫碱、2-氨基苯甲酸[1-(2-羟基苯基)亚丙基]酰肼(H2abph)及其单核配合物[Mn(Habph)2]和一维配位聚合物[Cu(abph)·DMSO]n和[Zn2(abph)2·2DMSO]n，并通过各种物理化学和光谱技术进行了表征。化合物的分子结构也通过单晶X射线晶体学测定。配体与 Cu(II) 和 Zn(II) 在甲醇中反应生成聚合物配合物，而与 Mn(II) 的类似反应则形成环化喹唑啉衍生物 2,2-二甲基-3-(1-苯基-亚丙基氨基)-2,3-二氢-1H-喹唑啉-4-酮。然而，配体与乙醇中的 Mn(II) 反应生成单核 Mn(II) 络合物。在Mn(II)配合物中，配体通过偶氮甲碱-N、羰基-O和酚盐-O进行配位，在金属离子周围形成6配位的扭曲八面体几何形状。在 Cu(II) 和 Zn(II) 配合物中，配体通过偶氮甲碱-N、羰基-O 和酚基-O 结合。 Cu(II)络合物形成扭曲的方形平面几何形状，通过第二单元的邻氨基苯甲酸-NH2基团聚合。 Zn(II) 络合物呈现酚盐-O 桥联二聚体，通过邻氨基苯甲酸-NH2 基团聚合，在每个金属离子周围形成 5 配位扭曲的四角锥几何形状。合成的化合物在 1 M HCl 介质中对低碳钢表现出明显的缓蚀性能，其顺序变化为：H2abph < Mn(II) 络合物 < Cu(II) 络合物 < Zn(II) 络合物。
A Schiff base, 2-amino-benzoic acid [1-(2-hydroxy-phenyl)-propylidene]-hydrazide (H2abph) and its mononuclear complex [Mn(Habph)2] and one-dimensional coordination polymers [Cu(abph)·DMSO]nand [Zn2(abph)2·2DMSO]nhave been synthesised and characterised by various physico-chemical and spectroscopic techniques. The molecular structures of the compounds are also determined by single crystal X-ray crystallography. The reaction of ligand with Cu(II) and Zn(II) in methanol gives polymeric complex, while the similar reaction with Mn(II) results in the formation of a cyclised quinazoline derivative 2,2-dimethyl-3-(1-phenyl-propylideneamino)-2,3-dihydro-1H-quinazolin-4-one. However, the reaction of ligand with Mn(II) in ethanol gives a mononuclear Mn(II) complex. In Mn(II) complex, the ligand coordinates through azomethine-N, carbonyl-O and phenolate-O forming a 6-coordinate distorted octahedral geometry around metal ion. In Cu(II) and Zn(II) complexes, the ligand bonds through azomethine-N, carbonylate-O and phenolate-O. The Cu(II) complex forms a distorted square planar geometry, which polymerises via anthranilate-NH2group of second unit. The Zn(II) complex exhibits a phenolate-O bridged dimer, which polymerises through anthranilate-NH2group forming a 5-coordinate distorted square pyramid geometry around each metal ion. The synthesised compounds show an appreciable corrosion inhibition property for mild steel in 1 M HCl medium which varies in the order: H2abph < Mn(II) complex < Cu(II) complex < Zn(II) complex.