Hydrothermal Chemistry of Oxomolybdenum-1,4-Carboxyphenylphosphonates in the Presence of M(II)-Organonitrogen Building Blocks (M(II) = Co, Ni, and Cu).

Hydrothermal methods were used to prepare a series of materials of the M(II)-L′/Mo x O y /H 2 O 3 PC 6 H 4 CO 2 H family, where M(II) = Co, Ni, or Cu and L′ = 2,2′-bipyridine (bpy), o -phenanthroline (phen), or 2,2′:6,2′′-terpyridine (terpy). The common {Mo 5 O 15 (O 3 PR) 2 } 4− cluster provided a building block for the one-dimensional (1D) structure of [{Cu(bpy)(H 2 O)} 3 {O 2 CC 6 H 4 PO 3 } 2 Mo 5 O 15 ]·4.5H 2 O ( 1 ·4.5H 2 O). While the pentamolybdate cluster was observed for [Co(terpy) 2 ][Mo 5 O 14 (OH){HO 2 CC 6 H 4 PO 3 } 2 ]·5.25H 2 O ( 5 ·5.25H 2 O) and [Ni(phen) 2 (H 2 O) 2 ][Ni(phen) 2 Mo 5 O 15 {HO 2 CC 6 H 4 PO 3 } 2 ]·2H 2 O ( 6 ·2H 2 O), the clusters are present as discrete molecular anions. In contrast, the 1D structure of [Cu(bpy){O 3 PC 6 H 4 CO 2 H}Mo 2 O 6 ] ( 2 ) exhibits a {Mo 2 O 6 } n 2 n + chain, decorated with phosphonate and {Cu(phen)} 2+ groups. The three-dimensional (3D) structure of [{Cu(phen)} 2 Mo 2 O 5 {O 3 PC 6 H 4 CO 2 } 2 ]·H 2 O ( 3 ·H 2 O) is constructed from {Mo 2 O 5 } 2+ binuclear units, linked into chains through bridging {Cu(phen)} 2+ groups; the chains are in turn connected through the dipodal carboxyphenylphosphonate ligands to produce the overall 3D connectivity. Fluoride incorporation in [Cu(bpy){O 3 PC 6 H 4 CO 2 }MoO 2 F] ( 4 ) results in mononuclear {MoO 5 F} octahedra linked through {Cu(bpy)} 2+ units and the organophosphonate ligand into a chain. The molecular structure of the second polyoxofluoromolybdate species [Co(bpy) 3 ] 2 [Mo 12 F 4 O 34 (H 2 O) 4 {O 3 PC 6 H 4 CO 2 H} 2 ]·4H 2 O ( 7 ·4H 2 O) consists of discrete {Co(bpy) 3 } 2+ cations and [Mo 12 F 4 O 34 (H 2 O) 4 {O 3 PC 6 H 4 CO 2 H} 2 ] 4− anionic clusters. The unique dodecamolybdate unit of 7 consists of two {Mo 6 F 2 O 17 (H 2 O) 2 (O 3 PR) 2 } 2− subunits fused through two bridging oxo-groups.