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

Abstract

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 V(x)O(y)/organophosphonate family [VO(H2L1)] (1), [VO(H2L2)] (2), [V2O2(H2O)2(L3)] x 1.5 H2O (3 x 1.5 H2O), [V2O2(H2O)2(L4)] x 2 H2O (4 x 2 H2O), and [V3O3(OH)(H3L5)2] x 7.5 H2O (6 x 7.5 H2O). The reactions were carried out in the presence of HF, and in one case, fluoride was incorporated to provide [V2F(OH)(H2O)3(L4)] x 2.25 H2O (5 x 2.25 H2O). 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 V(x)O(y)/alkyldiphosphonate series.

Hydrothermal Syntheses and Crystal Structures of Two New Vanadium Phosphates

“…Compound 2 was obtained when soluble NH 4 VO 3 was replaced by insoluble V 2 O 5 , having structure similar to reported vanadium phosphates [27]. [37][38][39][40][41].…”

“…Many variables influence the construction of the structure, such as the nature of the precursors, pH, temperature, stoichiometries, fill volume, time, autogenous pressure, and the interaction of the organic and the inorganic part [16]. Though vast numbers of vanadium phosphates have been reported, most of them possess infinite structures including one-dimensional (1D) [17][18][19], two-dimensional (2D) [20][21][22][23], and threedimensional (3D) [24][25][26][27][28], whereas only a few examples are discrete [29][30][31]. In this work, we successfully synthesized two new discrete vanadium phosphates (NH 4 ) 5 .…”

Metal-organodiphosphonates: Structural consequences of introducing aromatic tethering groups. The structures of [Cu(phen){HO3P(C12H8)PO3H}], [{Cu(phen)}2{HO3P(C12H8)PO3H}] and [Cu(terpy){HO3P(C12H8)PO3H}] and of the bimetallic materials [{Cu(LL)}2MoO2{HO3P(C12H8)PO3H}3] (LL=2,2-bipyridine, o-phenanthroline)

“…For example, the oxovanadium diphosphonates of the type [V 2 O 2 (H 2 O) x {O 3 P(CH 2 ) n PO 3 }]ÁxH 2 O exhibit three structure types depending on the tether length n [17]. Similarly, the structures of the oxovanadates of the aromatic diphosphonates are quite distinct from those of their aliphatic counterparts [18]. Structural variations are also observed for the oxomolybdateorganodiphosphonate structures [19].…”

A bimetallic oxide framework, [{Cu(bpy)}2Mo4O10(O3PCH2C6H4CH2PO3)2], constructed from novel chains

“…[16]. Since we had previously demonstrated that aromatic diphosphonate ligands provided dramatically different structures than a,x-alkyldiphosphonates in the V x O y -diphosphonate system [17,18] Compound 1 was isolated as bright blue crystals from the hydrothermal reaction of Cu(CH 3 CO 2 ) 2 ÁH 2 O, 2,2 0 -bipyridine, p-xylene diphosphonic acid, MoO 3 and HF in water at 200°C for 2 days [19]. Hydrothermal reaction conditions have been demonstrated to be effective for the synthesis and crystallization of organic-inorganic oxide materials [20][21][22][23][24].…”