Controlled assembly of two new bicapped bisupporting Keggin-polyoxometalate derivatives: [M(2,2′-bpy)2(H2O)]2[SiMoVI8MoV4VIV2O42] (M=Co, Zn)

Abstract: Two new neutral bicapped bisupporting Keggin-polyoxometalate derivatives: [M(2,2′-bpy)2(H2O)]2[] (M=Co 1, Zn 2; 2,2′-bpy=2,2′-bipyridine), have been synthesized under hydrothermal conditions by directly using H4SiMo12O40 as starting materials. Crystal data for compound 1: C40H36Co2Mo12N8O44SiV2, triclinic, space group , , , , , , , V=1706.3(6)Å3, ; for compound 2, C40H36Mo12N8O44SiV2Zn2, triclinic, space group , , , , , , , V=1709.6(6)Å3, . The studies of the electrochemical property of compounds 1 and 2 exhibit similar redox behavior to the parent [(C4H9)4N]4SiMo12O40, undergoing three two-electron reversible reductions. Variable-temperature magnetic susceptibility measurement of compound 1 demonstrates the presence of antiferromagnetic interactions. [Copyright &y& Elsevier]