Assembly of a series of Keggin-based multi- and mono-nuclear structures by tuning the bis(tetrazole)-functionalized thioether ligands
- 作者：Xiu-Li Wang ; wangxiuli@bhu.edu.cn ; Qiang Gao ; Ai-Xiang Tian ; Hai-Liang Hu ; Guo-Cheng Liu
- 关键词：Keggin polyoxometalate ; Multi-nuclear structure ; Oxidation state ; Flexible tetrazole-based thioethers ; Electrochemical property
- 刊名：Inorganica Chimica Acta
- 出版年：2012
- 期刊代码：40_00201693
- 类别：ch
- 出版时间：1 April, 2012
- 卷：384
- 期：Complete
- 页码：62-68
- 文件大小：997 K
摘要
Four Keggin-based compounds, [CuI2(bmtm)3]2路[CuI2(bmtm)4]路(PW12O40)2 (1), (bmtm = 1,1鈥?bis(1-methyl-5-mercapto-1,2,3,4-tetrazole)methane), [CuI3(bmte)3(PW12O40)] (2) (bmte = 1,2-bis(1-methyl-5-mercapto-1,2,3,4-tetrazole)ethane), [CuII(bmtb)3(HPW12O40)] (3) and [CuII(bmtb)3(HPMo12O40)] (4) (bmtb = 1,4-bis(1-methyl-5-mercapto-1,2,3,4-tetrazole)butane), have been designed and synthesized under hydrothermal conditions. By tuning the bis(tetrazole)-functionalized thioether ligands, compounds 1-4 exhibit Keggin-based bi-, tri- and mono-nuclear structures respectively, in which copper ion is +I oxidation state in compounds 1-2, and +II oxidation state in compounds 3-4. Compound 1 is composed of three moieties, [PW12O40]3鈭?/sup> anion and two kinds of bi-nuclear subunits [CuI2(bmtm)3]2+ and [CuI2(bmtm)4]2+. There exist abundant hydrogen-bonding and aryl stacking interactions inducing a two-dimensional (2D) supramolecular network of compound 1. Compound 2 exhibits a tri-nuclear cluster [CuI3(bmte)3]3+, which is connected by [PW12O40]3鈭?/sup> anions to construct a 1D chain. Compounds 3 and 4 are isostructural, and show 2D layer structures, which are constructed from Keggin anions and mono-nuclear [CuII(bmtb)3]2+. In this 2D layer, the Keggin anions act as bidentate linkages to connect the CuII-btmb chains. The oxidation states of copper ions show great influence on the mono- and multi-nuclear structures of this series. In addition, the electrochemical properties of the title compounds have been investigated.