Construction of two-dimensional supramolecular structure containing water tetramer and octamer

The structure of {[Co(pht)(bpy)(H2O)]·3H2O}n (pht is phthalate and bpy is 4,4'-bipyridine) and the role of solvent water clusters in structure stability

The Co(II) cation in poly[[aqua(μ-benzene-1,2-dicarboxylato-κ(3)O(1),O(2):O(1))(μ-4,4'-bipyridine-κ(2)N:N')cobalt(II)] trihydrate], {[Co(C8H4O4)(C10H8N2)(H2O)]·3H2O}n, is octahedrally coordinated by two N atoms of two 4,4'-bipyridine ligands, three O atoms from phthalate anions and a fourth O atom from a coordinated water molecule. The packing consists of planes of coordination polymers linked by hydrogen bonds mediated by three solvent water molecules; the linkage is achieved by the water molecules forming intricate oligomeric clusters which also involve the O atoms of the phthalate ligands.

μ-2,5-Dihydroxyterephthalato-bis[triaqua(1,10-phenanthroline)zinc] dihydroxyterephthalate

In the title compound, [Zn₂(C₈H₄O₆)(C₁₂H₈N₂)₂(H₂O)₆](C₈H₄O₆), the complete ions of both the binuclear dication and the dianion are generated by crystallographic inversion symmetry. The Zn atom is bonded to an N,N′-bidentate phenanthroline ligand, three water moleules and an O-mono­denate 2,5-dihy­droxy­terephthalate dianion. In the resulting distorted octa­hedral ZnN₂O₄ coordination poly­hedron, the water O atoms are in a mer orientation. Two intra­molecular O—H⋯O hydrogen bonds occur in the bridging 2,5-dihy­droxy­terephthalate dianion within the complex cation and also in the free dianion. An intra­molecular O_w—H⋯O (w = water) hydrogen bond also occurs within the dication. In the crystal, O—H⋯O hydrogen bonds link the component ions into a three-dimensional network.

Water-chloride and water-bromide hydrogen-bonded networks: influence of the nature of the halide ions on the stability of the supramolecular assemblies

Two compounds, namely, [TTPH(2)](Cl)(2) x 4 H(2)O (1) and [TTPH(2)](Br)(2) x 4 H(2)O (2), (TTP = 4'-p-tolyl-2,2':6',2''-terpyridine) were synthesized from purely aqueous media and characterized by physical techniques. In the solid-state structures of these compounds, interesting supramolecular assemblies are observed. In 1, an unusual staircase-like architecture of the tape of edge-shared planar water hexamer is of importance, where the chloride ions are at the two edges of the tape. In 2, the polymeric nature of the water-bromide assembly is of interest, where discrete open-cube water octamers are doubly bridged by bromide ions. Semiempirical and DFT calculations confirm that the nature of the anion indeed affects the topology of the water-halide assemblies. We conclude that the protonated [TTPH(2)](2+) species can act as appropriate receptors for halide ions, which in turn act as a matrix for the formation of polymeric 1D water-halide assemblies.