Poly[diaquadi-μ-hydroxido-κ⁴O:O-dinitrato-κ⁴O:O′-bis­[3-(pyridin-4-yl-κN)-5-(pyridin-3-yl)-1,2,4-oxadiazole]dicopper(II)]

The title compound, [Cu₂(NO₃)₂(OH)₂(C₁₂H₈N₄O)₂(H₂O)₂]_n, consists of a neutral polymeric Cu^II complex in which each Cu^II atom has a distorted octa­hedral geometry defined by a pyridyl N atom from a 3-(pyridin-3-yl)-5-(pyridin-4-yl)-1,2,4-oxadiazole ligand and five O atoms from a water mol­ecule, two nitrates and two hydroxides. Two Cu^II ions are bridged by two hydroxide anions resulting in a Cu₂O₂ loop, located across an inversion center and connected by the nitrate anions into a broad two-dimensional polymeric structure parallel to (100). In the crystal, there are O—H...O hydrogen bonds between the coodinated water mol­ecule and the nitrate and hydroxide, and between the hydroxide and the nitrate. Inter­molecular π–π inter­actions are present between pyridine rings in adjacent two-dimensional structures, with a centroid–centroid distance of 3.582 (2) Å.

3,4-Bis(4-meth­oxy­phen­yl)-2,5-dihydro-1H-pyrrole-2,5-dione

In the title compound, C₁₈H₁₅NO₄, the benzene rings form quite different dihedral angles [16.07 (1) and 59.50 (1)°] with the central pyrrole ring, indicating a twisted mol­ecule. Conjugation is indicated between the five- and six-membered rings by the lengths of the C—C bonds which link them [1.462 (3) and 1.477 (3) Å]. The most prominent feature of the crystal packing is the formation of inversion dimers via eight-membered {...HNCO}₂ synthons.