catena-Poly[piperazindiium [zincate(II)-bis(μ-pyridine-2,3-dicarboxylato)-κ³N,O²:O³;κ³O³:N,O²] tetrahydrate]

Abstract

n or {(pipzH 2 )[Zn(py-2,3-dc) 2 ]Á-4H 2 O} n , where py-2,3-dcH 2 is pyridine-2,3-dicarboxylic acid and pipz is piperazine, was obtained by the reaction of zinc(II) nitrate tetrahydrate with (pipzH 2 )(py-2,3-dc) as a protontransfer compound in aqueous solution. Each Zn II (site symmetry 1) is coordinated in a distorted octahedral geometry by four O atoms and two N atoms from two bidentate (py-2,3dc) 2À ligands, which also act as bridging ligands between Zn II atoms. The four donor atoms of the two coplanar (py-2,3-dc) 2À anions form a square-planar arrangement around the Zn II centre. In the crystal structure, extensive O-HÁ Á ÁO, N-HÁ Á ÁO and C-HÁ Á ÁO hydrogen bonds, as well as ion pairing andstacking [with a distance of 3.8693 (8) Å between two aromatic rings] between different fragments, play an important role in the stabilization of the supramolecular structure.

A brief review on structural concepts of novel supramolecular proton transfer compounds and their metal complexes

“…In the title proton transfer ion pair [87], although the orientation of two carboxylate groups is not in such a manner that the anionic fragment can act as good as pyridine-2,6-dicarboxylate ion in its many complexes, it can well coordinate to some metallic ions such as Zn II and Cd II [88,89].…”

Chromium(III) and Calcium(II) complexes obtained from dipicolinic acid: Synthesis, characterization, X-Ray crystal structure and solution studies

“…Well separated 1377 and 1271 cm -1 absorbances confirm the above-described phenomenon. Since hydrogen bonding is known to lower a carboxylate stretching frequency by 30-40 cm -1 [7], the transition at 1621 cm -1 can be assigned to the formation of strong hydrogen bonding interaction by carboxylate group.…”

“…The important characteristic of this compound is the infinite one dimensional chains based on [1][2][3][4][5][6][7][8][9][10] and [1][2][3][4][5][6][7][8][9][10] vectors. The crystal structure lattice of (1) is constructed via three kinds of interactions rather than ion pairing.…”

“…Furthermore carboxylic acids are tentative for coordination to metal centers by different coordinative modes. The metal carboxylate complexes are vastly studied [3][4][5][6][7][8][9][10][11][12], clearly indicating the fact that compounds with multiple carboxylic acid groups are good targets for supramolecular architectures and coordination polymers [4][5][6][7].…”

Poly[piperazinediium [aquabis(μ-pyridine-2,5-dicarboxylato)zincate] dihydrate]

“…For related literature, see: Aghabozorg et al (2007Aghabozorg et al ( , 2007a; Sheshmani et al (2007).…”