| Six polyoxometalate coordination compounds have been synthesized on the basis of vanadium-substituted Keggin polyoxoanion (POM) clusters as building blocks decorated or bridged by various transition metal compounds under hydrothermal or solvothermal conditions. These compounds have been structurally characterized by elemental analyses as well as with IR, TG and X-ray single crystal diffractions. The exploration study on synthetic conditions and rules for six new compounds are also carried out.1. Two Ag+ complexes have been hydrothermally synthesized on the basis of Keggin type polyoxoanions [PW10V2O40]5-.[Ag(dpa)2(H2O)2]2[H3PW10V2O40]·2dpa·6H2O (1)[Ag(2,2'-bipy)2]6{[Ag(2,2'-bipy)]2[PW10V2O40]}2 (2)Complex 1 is a discrete compound constructed from [PW10V2O40]5-,[Ag(dpa)2(H2O)2]+,free dpa and water molecules. The polyoxoanions and free dpa molecules array alternantly through hydrogen bonding andπ-πstacking interactions, forming an 1D supramolecular chain. Complex 2 is a discrete compound constructed from [Ag2(2,2'-bipy)]2[PW10V2O40]3- (Ag2-POMs),[Ag4(2,2'-bipy)]2[PW10V2O40]3- (Ag4-POMs) and [Ag(2,2'-bipy)2]+ units. The one-dimensional chain in complex 2 is linked alternately by Ag2-POMs and Ag4-POMs moieties through hydrogen bonding andπ-πstacking interactions.2. Two 1D and 2D polyoxometalate coordination compounds based on [PW10V2O40]5- and [PW9V3O40]6- have been hydrothermally synthesized.{[Ni(4,4'-bipy)1.5(OH)(H2O)]2[H3PW10V2O40]}·4H2O (3){[Ni(dpa)2][Ni(dpa)(H2O)3]2[PW9V3O40]}·4H2O (4)In complex 3, nickel ions are linked into an 1D infinite zigzag {Ni2(4,4'-bipy)3(OH)2(H2O)2}n2+ chains via hydroxyl groups and 4,4'-bipy molecules. The chains are bridged via [PW10V2O40]5- anions into a 2D layered structure. In complex 4, [Ni(dpa)(H2O)3]2+ and [PW9V3O40]6- are linked into the bis-supported {[Ni(dpa)(H2O)3]2 [PW9V3O40]}2- fragments, which are bridged with [Ni(dpa)2]2+ units via two terminal oxygen atoms of the polyoxoanions, forming an 1D chain-like structure.3. Two polyoxometalate coordination compounds have been synthesized emplying acetic acid as reaction solvent, on the basis of [PW11VO40]4- and [PW10V2O40]5-.{[Cu(dpa)]4[PW11VO40]} (5){[Cu(dpa)(4,4'-bipy)0.5(H2O)]2[HPW10V2O40]}·dpa (6) In complex 5, polyoxoanions [PW11VO40]4- and four [Cu(dpa)]+ units are linked into forming an 1D supramolecular chains through hydrogen bonding interactions between N of dpa and O of polyoxoanions. The chains are further packed into a 2D supramolecular layer networks viaπ-πstacking interactions. In complex 6, [Cu(dpa)(H2O)]2+ and [PW10V2O40]5- are linked into four-supported 1D [Cu(dpa)(H2O)]2POMs chains. 2D layer structure is constructed from 1D infinite [Cu(dpa)(H2O)]2POMs chains bridged via 4,4'-bipy ligands.
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