Solvothermal Assembly of a Series of Organic–Inorganic Hybrid Materials Constructed from Keggin Polyoxometalate Clusters and Copper(I)–Organic Frameworks
datasetposted on 04.05.2011, 00:00 by Hai-Yan Liu, Hua Wu, Jin Yang, Ying-Ying Liu, Jian-Fang Ma, Hong-Ye Bai
Seven polyoxometalate (POM) hybrid materials based on Keggin polyanion building blocks and copper(I)–organic frameworks with pyrazine derivatives, namely, [CuI4(2Et,3Me-Pyr)5(SiW12O40)] (1), [CuI4(2,6-Pyr)4(SiW12O40)] (2), [CuI4(2,5-Pyr)4(SiW12O40)(H2O)2] (3), [CuI4(2,3,5,6-Pyr)4(SiW12O40)](H2O) (4), [CuI4(2,5-Pyr)4(PMoVI11MoVO40)]·1.5H2O (5), [CuI3(2,3,5-Pyr)4(PMo12O40)]·H2O (6), and [CuI4(2Et,3Me-Pyr)5(PMoVI11MoVO40)] (7), where 2Et,3Me-Pyr = 2-ethyl-3-methylpyrazine, 2,6-Pyr = 2,6-dimethylpyrazine, 2,5-Pyr = 2,5-dimethylpyrazine, 2,3,5-Pyr = 2,3,5-trimethylpyrazine, and 2,3,5,6-Pyr = 2,3,5,6-tetramethylpyrazine, have been synthesized under solvothermal conditions. In 1 and 7, polyanions link CuI–organic sheets to generate 3D (3,4)-connected frameworks. In 2, the polyanion bridges CuI–organic chains to yield a 3D (3,4,6)-connected framework. Both 3 and 4 exhibit 2D double layer structures. In 5, the Keggin polyanion bridges the CuI–Pyr chains to form an infinite 3D (3,4)-connected framework. In 6, CuI cations are bridged by the 2,3,5-Pyr and Keggin polyanions to generate a novel 2D (8,3) sheet. The roles of the pyrazine derivatives and the Keggin polyanions in the formation of the POM-based MOFs have been discussed.