A novel 1D tungstoarsenate with mixed organic ligands assembled by hexa-Cu sandwiched Keggin units and dinuclear copper-oxalate complexes

A novel transition metal substituted tungstoarsenate [Cu2(phen)2(μ-ox)]{[Cu(phen)(H2O)2][Cu4 (H2O)4Cu2(phen)2(AsW9O33)2]}·6H2O (ox = oxalate, phen = 1,10-phenanthroline) (1) has been synthesized by reaction of K14[As2W19O67(H2O)]·nH2O, CuCl2·2H2O, H2C2O4·2H2O and phen under hydrothermal conditions and characterized by elemental analyses, IR and UV spectra and X-ray single-crystal diffraction. 1 displays a 1D chain architecture constructed by alternating hexa-Cu sandwiched units {[Cu(phen)(H2O)2]2[Cu4(H2O)4Cu2(phen)2(AsW9O33)2]}2− and dinuclear copper(II)-oxalate complexes [Cu2(phen)2(μ-ox)]2+. The 3D supramolecular network can be established by intra- and inter-molecular π–π packing interactions. To the best of our knowledge, 1 represents the first 1D chain-like inorganic–organic hybrid tungstoarsenate with mixed organic ligands containing hexa-nuclear sandwiched units bridged by copper-oxalate complex linkers.