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

Two new neutral bicapped bisupporting Keggin-polyoxometalate derivatives: [M(2,2′-bpy)2(H2O)]2[image] (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 image, image, image, image, image, image, image, V=1706.3(6) Å3, image; for compound 2, C40H36Mo12N8O44SiV2Zn2, triclinic, space group image, image, image, image, image, image, image, V=1709.6(6) Å3, image. 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.