The Hydrothermal and Structural Chemistry of Oxovanadium−Arylphosphonate Networks and Frameworks

The hydrothermal reactions of NH4VO3 with the aromatic phosphonate ligands 1,4-, 1,3-, and 1,2-phenylenediphosphonic acids (H4L1, H4L3, H4L4, respectively); biphenyl-4,4′-diyldiphosphonic acid (H4L2); and 1,3,5-tris(phenyl)-4,4′-triphosphonic acid (H6L5) yielded materials of the VxOy/organophosphonate family [VO(H2L1)] (1), [VO(H2L2)] (2), [V2O2(H2O)2(L3)]·1.5H2O (3·1.5H2O), [V2O2(H2O)2(L4)]·2H2O (4·2H2O), and [V3O3(OH)(H3L5)2]·7.5H2O (6·7.5H2O). The reactions were carried out in the presence of HF, and in one case, fluoride was incorporated to provide [V2F(OH)(H2O)3(L4)]·2.25H2O (5·2.25H2O). The materials exhibit diverse structural chemistry, including the prototypical buttressed layer architecture for 1 and 2, a complex three-dimensional structure for 3, and unique two-dimensional structures for 4, 5, and 6. The structures of this oxovanadium−arylphosphonate family are quite distinct from those previously described for the VxOy/alkyldiphosphonate series.