Hexaaqua­copper(II) bis­(tetra­fluorido­borate)–pyrazine 1,4-dioxide (1/3)

The crystal structure of the title compound, [Cu(H(2)O)(6)](BF(4))(2)·3C(4)H(4)N(2)O(2), comprises discrete [Cu(H(2)O)(6)](2+) cations and BF(4) (−) anions along with three equivalents of pyrazine 1,4-dioxide (pzdo). The hexa­aqua­copper(II) ion and all three pzdo mol­ecules lie about crystallographic inversion centers. The lattice is supported by an extensive hydrogen-bonding network. O—H⋯O hydrogen bonding between the [Cu(H(2)O)(6)](2+) and pzdo units creates a pseudo-hexa­gonal lattice parallel to the bc plane. The BF(4) (−) anions lie in the voids of that lattice, held in place by O—H⋯F hydrogen bonds, and also generate BF(4) (−)–pzdo–BF(4) (−)–pzdo stacks via short F⋯N contacts [2.866 (3)–3.283 (4) Å].