Phosphonate based hybrid organic/inorganic open network compounds [Cu(bipy)(VO2)2(O3PCH2PO3)H2O] and [Cu(bipy)(VO2)(O3P(CH2)2PO2OH)] · 1.5H2O

The hybrid organic/inorganic copper oxovanadium diphosphonates of formula [Cu(bipy)(VO2)2(O3PCH2PO3)H2O] 1, which crystallizes in the orthorhombic symmetry, and [Cu(bipy)(VO2)(O3P(CH2)2PO2OH)] · 1.5H2O 2, which crystallizes in the monoclinic symmetry, were obtained by the soft hydrothermal route. The layered VPOC structure of 1 may be described as a undulating (VO2)2(O3PCH2PO3)(H2O)2− network formed by the link between the V2PCO10 rings via the diphosphonate fragments, creating 18-membered {V4P5C2O7} cavities. The corrugated lamellar structure of 2 is obtained by the interconnection of four oxovanadium phosphorus V4P8C8O8 anionic rings with diphosphonate fragments, forming 28-atom cavities. In both compounds the copper diimine cation groups are coordinated to the chelating oxygen atoms of the PO3 and oxovanadium groups, and do not participate in building the 2D-structure.