29-Dimethyl-110-phenanthrolin-1-ium (6-carb­oxy-4-hy­droxy­pyridine-2-carboxyl­ato-κ3 O 2NO 6)(4-hy­droxy­pyridine-26-dicarboxyl­ato-κ3 O 2NO 6)zincate(II) 2.35-hydrate: a proton-transfer compound

摘要

In the title compound, (C14H13N2)[Zn(C7H3NO5)(C7H4NO5)]·2.35H2O, the Zn^II atom is coordinated by two N atoms and four O atoms from the carboxyl­ate groups of the 4-hy­droxy­pyridine-2,6-dicarboxyl­ate and 6-carb­oxy-4-hy­droxy­pyridine-2-carboxyl­ate ligands, forming a distored octa­hedral geometry. In the anion, the two pyridine rings are inclined to one another by 87.75 (13)°. Two types of robust O—H⋯O hydrogen bond synthons, viz. R 2 ²(16) and R 6 ⁶(42), link the anions to form a two-dimensional network parallel to the bc plane. Furthermore, O—H⋯O, N—H⋯O, N—H⋯N and weak C—H⋯O hydrogen bonds connect the two dimensional networks, forming a three-dimensional structure. In the crystal, there are also C—H⋯π and π–π inter­actions [centroid–centroid distances of 3.5554 (18) and 3.7681 (18) Å], and C=O⋯π inter­actions [O⋯centroid distance = 3.117 (2) Å] present. One of the three crystal water molecules shows an occupancy of 0.35.