Poly[[octaaqua-μ₄-(benzene-1,2,4,5-tetracarboxylato)-dicobalt(II)] octahydrate]

Abstract

The title polymeric coordination compound, {[Co2(C10H2O8)(H2O)8]·8H2O}n, was obtained by slow diffusion of a dilute aqueous solution of CoCl2and the sodium salt of benzene-1,2,4,5-tetracarboxylic acid (H4btec) through an agar–agar gel bridge in a U-shaped tube. The two independent Co2+ions are each situated on an inversion centre and are coordinated in a slightly distorted octahedral geometry by four water O atoms and two carboxylate O atoms from two btec4−ligands (-1> symmetry), forming a layer parallel to (11-1). This layer can be described as a molecular two-dimensional square grid with the benzene rings at the nodes and the CoIIatoms connecting the nodes. O—H...O hydrogen-bonding interactions involving the coordinating water molecules, the carboxylate O atoms and lattice water molecules lead to the formation of a three-dimensional network.

Poly[[hexaaquasesqui(μ-benzene-1,2,4,5-tetracarboxylato)dicopper(II)disodium] monohydrate]

“…A huge number of novel compounds with interesting crystal structures and topologies have been reported. As part of this research, benzene-1,2,4,5-tetracarboxylate (btec 4-) can be used as a ligand to form various supramolecular architectures through its four rigid carboxyl groups [see Camara et al (2013), Luo et al (2013), Gong & Zhang (2011), Liu et al (2010), Zhang et al (2007)]. In order to enrich this family of compounds, we recently undertook a study devoted to reactions of H 4 btec with metal ions in gel media.…”

“…For related structures, see: Camara et al (2013); Luo et al (2013); Gong & Zhang (2011); Liu et al (2010); Zhang et al (2007). For related crystal-growth methods in gels, see: Henisch (1988); Henisch & Roy (1970); Daiguebonne et al (2003).…”

M2(H2O)[μ10‐C6H2(COO)4] (M = Ba2+, Pb2+) – Two Isotypic Three‐Dimensional Coordination Polymers with a Layer‐like Separation between Anions and Cations

“…The obtained crystal structures strongly depend on the reaction conditions. For instance, the reaction between Co 2+ and benzene-1,2,4,5-tetracarboxylic acid results either in a onedimensional structure (chain-like) [4], a two-dimensional layer-like structure [ 20 ] or in a three-dimensional framework [2123]. Previous studies on benzene-1,2,4,5tetracarboxylato complexes with main group metal ions like Mg 2+ , Sr 2+ and Al 3+ reveal three-dimensional structures with zeolite-like features [ 24  26 ].…”