Dichloridobis(4-pyridylmethyl 1H-pyrrole-2-carboxylate-κN)zinc

In the title molecule, [ZnCl2(C11H10N2O2)2], the ZnII ion, situated on a twofold axis, is in a distorted tetrahedral coordination environment formed by two chloride anions and two pyridine N atoms of the two organic ligands. In the pyrrole-2-carboxylate unit, the pyrrole N—H group and the carbonyl group point approximately in the same direction. The dihedral angle between the two pyridine rings is 54.8 (3)°. The complex molecules are connected into chains extending along [101] by N—H⋯Cl hydrogen bonds. The chains are further assembled into (-101) layers by C—H⋯O and C—H⋯Cl interactions.

In the title molecule, [ZnCl 2 (C 11 H 10 N 2 O 2 ) 2 ], the Zn II ion, situated on a twofold axis, is in a distorted tetrahedral coordination environment formed by two chloride anions and two pyridine N atoms of the two organic ligands. In the pyrrole-2-carboxylate unit, the pyrrole N-H group and the carbonyl group point approximately in the same direction. The dihedral angle between the two pyridine rings is 54.8 (3) . The complex molecules are connected into chains extending along [101] by N-HÁ Á ÁCl hydrogen bonds. The chains are further assembled into (101) layers by C-HÁ Á ÁO and C-HÁ Á ÁCl interactions.
Combination of coordination bonding and hydrogen bonding is an effective strategy for the generation of supramolecular networks. Continuing our study, herein we report the crystal structure of the complex obtained with 4-pyridylmethyl-1Hpyrrole-2-carboxylate and ZnCl 2 .
A perspective view of the title compound with atomic labeling is shown in Fig. 1. The complex consists of one ZnCl 2 and two ligand molecules, in which both the pyrrole-2-carboxylate moieties adopted syn conformation with the carbonyl group arranged in the same direction as the adjacent pyrrole N-H group. In the complex, the dihedral angle between the two pyridine rings is 54.8 (3)°. The complex molecules assemble into layer structrue through N-H···Cl, C-H···O and C -H···Cl hydrogen bonds (Fig. 2).

Refinement
All H atoms were placed in calculated positions (C-H = 0.93 -0.97 Å; N-H = 0.86 Å) and refined as riding on their carrier atoms with U iso (H) = 1.2 U eq (C, N).

Figure 2
The layer of the title molecules assembled by intermolecular hydrogen bonds (hydrogen bonds are shown as dashed lines).

Dichloridobis(pyridin-4-ylmethyl 1H-pyrrole-2-carboxylate-κN)zinc
Crystal data Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq