Two two-dimensional hydrogen-bonded coordination networks: bis(3-carboxybenzoato-kappaO)bis(4-methyl-1H-imidazole-kappaN3)copper(II) and bis(3-methylbenzoato-kappaN)bis(4-methyl-1H-imidazole-kappaN3)copper(II) monohydrate.

The title two-dimensional hydrogen-bonded coordination compounds, [Cu(C(8)H(5)O(4))(2)(C(4)H(6)N(2))(2)], (I), and [Cu(C(8)H(7)O(2))(2)(C(4)H(6)N(2))(2)].H(2)O, (II), have been synthesized and structurally characterized. The molecule of complex (I) lies across an inversion centre, and the Cu(2+) ion is coordinated by two N atoms from two 4-methyl-1H-imidazole (4-MeIM) molecules and two O atoms from two 3-carboxybenzoate (HBDC(-)) anions in a square-planar geometry. Adjacent molecules are linked through intermolecular N-H...O and O-H...O hydrogen bonds into a two-dimensional sheet with (4,4) topology. In the asymmetric part of the unit cell of (II) there are two symmetry-independent molecules, in which each Cu(2+) ion is also coordinated by two N atoms from two 4-MeIM molecules and two O atoms from two 3-methylbenzoate (3-MeBC(-)) anions in a square-planar coordination. Two neutral complex molecules are held together via N-H...O(carboxylate) hydrogen bonds to generate a dimeric pair, which is further linked via discrete water molecules into a two-dimensional network with the Schläfli symbol (4(3))(2)(4(6),6(6),8(3)). In both compounds, as well as the strong intermolecular hydrogen bonds, pi-pi interactions also stabilize the crystal stacking.