Poly[[μ2-2,2′-diethyl-1,1′-(butane-1,4-diyl)diimidazole-κ2 N 3:N 3′](μ2-5-hydroxyisophthalato-κ2 O 1:O 3)zinc]

In the title coordination polymer, [Zn(C8H4O5)(C14H22N4)]n, the ZnII cation is coordinated by an O2N2 donor set in a distorted tetrahedral geometry. The ZnII ions are linked by μ2-OH-bdc (OH-H2bdc = 5-hydroxyisophthalic acid) and bbie ligands [bbie = 2,2′-diethyl-1,1′-(butane-1,4-diyl)diimidazole], forming a two-dimensional layer parallel to the ab plane. The layers are further connected through intermolecular C—H⋯O and O—H⋯O hydrogen bonds, forming a three-dimensional supramolecular structure. In the bbie ligand, the two C atoms in the ethyl group are each disordered over two positions with a site-occupancy ratio of 0.69:0.31.

In the title coordination polymer, [Zn(C 8 H 4 O 5 )(C 14 H 22 N 4 )] n , the Zn II cation is coordinated by an O 2 N 2 donor set in a distorted tetrahedral geometry. The Zn II ions are linked by 2 -OH-bdc (OH-H 2 bdc = 5-hydroxyisophthalic acid) and bbie ligands [bbie = 2,2 0 -diethyl-1,1 0 -(butane-1,4-diyl)diimidazole], forming a two-dimensional layer parallel to the ab plane. The layers are further connected through intermolecular C-HÁ Á ÁO and O-HÁ Á ÁO hydrogen bonds, forming a threedimensional supramolecular structure. In the bbie ligand, the two C atoms in the ethyl group are each disordered over two positions with a site-occupancy ratio of 0.69:0.31.

Comment
As part of an investigation of the transition metal application there is a need to prepare further examples of these compounds.
In this paper, the structure of the title compound, (I), is described.
As shown in Fig. 1, the Zn II ions is four-coordinated by two oxygen atoms from two oxygen atoms of two OH-bdc anions and two nitrogen atoms of two bbie ligands. Each carboxylate group of OH-bdc acts in a monodentate mode, and the hydroxyl group is not involved in coordination. The bbie molecule coordinates to two Zn II cations through its two aromatic N atoms, thus acing as a bridging bidentate ligand. As illustrated in Fig. 2, The Zn II cations are connected by OH-bdc and bbie ligands to form a layer parallel to the ab plane. There exist hydrogen-binding interactions among adjacent layers. The layers are further connected by these hydrogen bonds to a 3D supramolecular architecture.

Experimental
The and water (8 ml) was sealed in a Teflon reactor (18 ml) and heated at 140 °C for 3 days. After the mixture had been cooled to room temperature at 10 °C.h -1 , colorless crystals of (I) were obtained. Yield: 43%.

Refinement
Disorderd bbie ligand was refined using C17 and C18 atoms split over two sites, with a total occupancy of 1. A l l H-atoms bound to carbon were refined using a riding model with d(C-H) = 0.93 Å, U iso = 1.2U eq (C) for aromatic and 0.97 Å, U iso = 1.5U eq (C) for CH 2 atoms. Hydroxyl H atoms were refined using a riding model with d(O-H) = 0.82 Å, U iso =1.5U eq (O). Fig. 1. A view of the local coordination of the Zn II cation of (I). Displacement ellipsoids are drawn at the 30% probability level. supplementary materials