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Two Co-substituted sandwich-type polyoxometalates (Hen)[Co(HO)(PWO)]{[Co(HO)][Co(HO)(PWO)]}·18HO ( 1) and (Hen)[Co(HO)(HGeWO)]{[Co(HO)][Co(HO)(HGeWO)]}·16HO ( 2) (en = ethylenediamine) have been hydrothermally synthesized and characterized by IR spectra, elemental analyses, thermogravimetric analyses, powder X-ray diffraction and single-crystal X-ray diffraction. Single-crystal structure analysis reveals that the molecules of 1 and 2 contain two Co-substituted sandwich-type polyoxoanions. This type of a molecular unit containing double polyoxoanions is very rare. From the viewpoint of supramolecular chemistry, the sandwich-type polyoxoanions in 1 and 2 can be further extended to 3-D frameworks via extensive hydrogen-bonding interactions. [ABSTRACT FROM AUTHOR]

Hydrothermal reactions of trilacunary precursor A- α-AsWO polyoxoanions and nickel ions in the presence of ethylenediamine (en = ethylenediamine) led to two new hexa-Ni-substituted Keggin-type tungstoarsenates [Ni( μ-OH)(en)(HO)(B- α-AsWO)]·6HO ( 1) and [Ni( μ-OH)(en)(HO)(B- α-AsWO)]·10HO ( 2), which have been characterized by elemental analyses, IR spectra, powder X-ray diffraction, thermogravimetric analyses and single-crystal X-ray diffraction. Crystal data for 1: hexagonal, R3 c, a = b = 20.4379(5) Å, c = 21.5062(6) Å, β = 120º, V = 7779.8 (3) Å and Z = 6; for 2: momoclinic, P2/ c, a = 13.4200(3) Å, b = 19.1428(5) Å, c = 22.8845(9) Å, β = 112.403(3)º, V = 5435.2(3) Å and Z = 4. Structural analyses reveal that the [Ni( μ-OH)(B- α-AsWO)] clusters in 1 and 2 are covalently functionalized by neutral en ligands, in which two similar {Ni( μ-OH)(en)(HO)} cores have been observed by our lab. Notably, 1 and 2 represent the highest number of substituted transition metal ions in all known lacunary Keggin-type polyoxotungstoarsenate monomers. [ABSTRACT FROM AUTHOR]

Four new hexa-nickel(II)-substituted Keggin-type tungstophosphates [Ni(μ-OH)(oeen)(HO)(B-α-PWO)]·6HO ( 1, oeen = N-(2-hydroxyethyl)enediamine), [Ni(μ-OH)(oeen)(HO)(B-α-PWO)]·13HO ( 2), [Ni(μ-OH)(oeen)(tran)(HO)(B-α-PWO)]·3HO ( 3, tran = 1,4,7-triazonane) and [Ni(μ-OH)(oeen)(tran)(HO)(B-α-PWO)]·6HO ( 4) have hydrothermally made by controlling their reaction temperatures. 1- 4 have been characterized by elemental analyses, IR spectra, powder X-ray diffraction, thermogravimetric analyses and single-crystal X-ray diffraction, respectively. Structural analyses reveal that they consist of {Ni(μ-OH)(HO)} cores and B-α-PWO (PW) units, and further are stabilized by organic neutral oeen/tran molecules. 1- 3 are isolated clusters while 4 is the 1D chain structure. It should be noted that the tran molecules in 3 and 4 are derived from the oeen molecules in the starting materials. [ABSTRACT FROM AUTHOR]

A tetra-Co substituted sandwich-type polyoxotungstate (HTED)Cs[Co(HO)(B- α-HPWO)]·28HO (TED = triethylenediamine) has been hydrothermally synthesized and characterized by IR spectrum, elemental analysis, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction, respectively. Single-crystal structure analysis reveals that the tetra-Co substituted sandwich-type phosphotungstate units [Co(HO)(B- α-PWO)] are combined together by Cs cations giving rise to the 3D framework with the 'sqc876' 3D net. [ABSTRACT FROM AUTHOR]

Two new organic-inorganic hybrid carboxylate-bridging copper-lanthanide heterometallic polyoxotungstates K[Cu(en)(HO)]{[Cu(en)][Ce(GeWO)(HO)](CO)}·11HO ( 1) and K [Cu(en)(HO)]{[Cu(en)(HO)][Tb(PWO)(CHCOO)(HO)]}·15HO ( 2) (en = 1,2-ethylenediamine) have been prepared under hydrothermal conditions and characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD), thermogravimetric (TG) analyses and X-ray single-crystal diffraction. X-ray structural analyses reveal that 1 exhibits the 1D zigzag chain architecture formed by dimeric oxalate-bridging {[Cu(en)][Ce(GeWO)(HO)](CO)} units and [Cu(en)] linkers whereas 2 displays a typical hybrid acetate-bridging dimeric structure [(α-PWO)Tb(HO)(η,μ-1,1)-CHCOO] modified by [Cu(en)(HO)] fragments. Notably, both contain 2:2-type carboxylate-bridging monolanthanide-substituted Keggin-type dimeric moieties and two types of organic ligands. 1 represents the rare 1D Cu-Ln heterometallic germanotungstate containing mixed ligands of en and oxalate whereas 2 represents the rare dimeric organic-inorganic hybrid Keggin-type phosphotungstate containing both Cu-Ln heterometals and mixed ligands of en and acetate. Graphical Abstract: Two new organic-inorganic hybrid copper-lanthanide heterometallic polyoxotungstates containing mixed organic ligands of en and carboxylate were successfully separated under hydrothermal conditions. 1 exhibits the 1D zigzag chain architecture formed by dimeric oxalate-bridging {[Cu(en)][Ce(GeWO)(HO)](CO)} units by [Cu(en)] linkers, whereas 2 displays a typical hybrid acetate-bridging dimeric structure [(α-PWO)Tb(HO)(η,μ-1,1)-CHCOO] modified by [Cu(en)(HO)] fragments.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

By introducing rigid aromatic N-ligands to the lacunary silicotungstate system under hydrothermal conditions, two new Keggin-type polyoxotungstate hybrids with copper-organic complexes [Cu(phen)(HO)][Cu(phen)][α-SiWO]·4HO ( 1) and [Cu(4,4′-bpy)]H[α-SiWO]·3 HO ( 2) (phen = 1,10-phenanthroline, 4,4′-bpy = 4,4′-bipyridine) have been made and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The common architectural feature of 1 and 2 is that both comprise the plenary Keggin-type [α-SiWO] polyoxoanions modified by Cu-organic fragments containing various organic ligands. It should be pointed out that {[Cu(phen) (HO)][α-SiWO]} and {[Cu(phen)][α-SiWO]} building units in 1 are alternately held together into an infinite 1-D chain fashion while the most striking characteristic of 2 is that two types of {-4,4′-bpy-Cu- 4,4′-bpy-Cu-} 1-D polymeric chains are combined together by hexadentate [α-SiWO] polyoxoanions as the inorganic bridging ligands, giving birth to the aesthetic 3-D extended architecture. Moreover, electrochemical properties of 1 and 2 have been investigated. [ABSTRACT FROM AUTHOR]

Two novel hexa-nickel(II)-substituted Keggin-type {NiPW}-based tungstophosphates [Ni( μ-Tris)(en)( Pr)(damp)(HO)(B- α-PWO)]·10HO ( 1) and [Ni( μ-Tris)(en)(damp)(HO)(B- α-PWO)]·7HO ( 2) (en = ethylenediamine, Pr = CHCHCOO, damp = 2-aminoisobutyrate, Tris = pentaerythritol) were hydrothermally synthesized and characterized by IR spectra, elemental analyses, powder X-ray diffraction, thermogravimetric analyses, and single-crystal X-ray diffraction. Crystal data for 1: orthorhombic, Pca2, a = 21.6962(7) Å, b = 20.6398(5) Å, c = 14.7825(4) Å, β = 90º, V = 6619.7(3) Å, Z = 4; for 2: orthorhombic, Pca2, a = 21.6978(9) Å, b = 20.6658(7) Å, c = 14.7767(4) Å, β = 90º, V = 6625.9(4) Å, Z = 4. 1 consists of a {Ni( μ-Tris)(en)( Pr)(damp)(HO)} core and a [B- α-PWO] (PW) unit and is covalently functionalized by one Pr and one damp, as well as en and Tris ligands. The structure of 2 is the same to 1 except that the Pr anion in 1 is substituted by the other damp ligand. Most interestingly, 1 contains four kinds of organic ligands, while 2 includes three kinds of organic ligands, which are first observed in polyoxometalate chemistry. [ABSTRACT FROM AUTHOR]

An organic -inorganic hybrid polyoxovanadoborate K(CHNH)[VBO(OH)-(HO)]·2en·12HO ( 1, en = ethylenediamine) has been synthesized under hydrothermal conditions and characterized by IR spectroscopy, element analyses, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. Single-crystal structure analysis reveals that 1 consists of a cage-like polyoxovanadium borate [VBO(OH)(HO)] cluster that is constructed from a puckered {BO(OH)} ring sandwiched by two triangle {VO} units, in which a water molecule is confined in the middle of the cage-like cluster. Interestingly, 1 represents the rare example of extended 3-D framework constructed from [VBO(OH)-(HO)] clusters through K cations. [ABSTRACT FROM AUTHOR]