Crystal structure of di-μ-aqua-μ-(pyrazine N,N′-dioxide)-κ(2) O:O-bis­(di­aqua­sodium) tetra­phenyl­borate dihydrate pyrazine N,N′-dioxide monosolvate

The search for novel lanthanide coordination networks using pyrazine N,N′-dioxide (pzdo, C(4)H(4)N(2)O(2)) as a structure-directing unit, led to the synthesis and the structure determination of the title compound, [Na(2)(C(4)H(4)N(2)O(2))(H(2)O)(6)][B(C(6)H(5))(4)](2)·C(4)H(4)N(2)O(2)·2H(2)O. The crystal structure is comprised of discrete [{Na(H(2)O)(2)}(2)(μ-H(2)O)(2)(μ-pzdo)](2+) cations and tetra­phenyl­borate anions, as well as pzdo and H(2)O solvent mol­ecules. The dinuclear cation is located about a twofold rotation axis, and the symmetry-related Na(I) atoms display a distorted square-pyramidal coordination sphere defined by two O atoms of terminal water ligands, two O atoms of bridging water ligands and one O atom of a bridging pzdo ligand. In the crystal, O—H⋯O hydrogen bonds link the dinuclear cation and solvent pzdo mol­ecules (point-group symmetry -1) into rectangular grid-like layers parallel to the bc plane. Additional C—H⋯O, O—H⋯O, C—H⋯π and O—H⋯π inter­actions link the anion and solvent water mol­ecules to the layers. The layers are further linked into a three-dimensional network through a combination of C—H⋯π and O—H⋯π hydrogen bonds involving the tetra­phenyl­borate anion.