Crystal structure of dichloridobis(methyl isonicotinate-κN)copper(II)

In the title compound, [CuCl2(C7H7NO2)2], the square-planar-coordinated CuII ion lies on a centre of symmetry and is bonded to two monodentate methylisonicotinate ligands through their N atoms and by two chloride ligands. The molecules pack in a herringbone pattern. Perpendicular to [100] there are weak intermolecular C—H⋯Cl and C—H⋯O contacts. Along [100] there are infinite chains of edge-sharing octahedra linked through the chlorido ligands

The molecular structure of the title compound possessing a crystallographic centre of inversion is depicted in Fig. 1.
The first coordination sphere of the Cu1 centre consists of two nitrogen atoms, from the isoniconate ligands, at a distance of 2.025 (2) Å and two chlorido ligands at a distance of 2.2962 (7) Å. The various N1-Cu1-Cl1 angles are close to 90° resulting in a square-planar first coordination sphere of Cu1. By coordination of two additional chlorido ligands from adjacent complexes at a distance of 2.9215 (7) Å from the Cu1 centre, the coordination sphere is expanded to a distorted octahedron. The pyridine ring and the Cu1-Cl1 bond are not coplanar, but enclose an angle of 59.00 (9)°. The Cu-N1 bond and the plane of the pyridine ring deviate from coplanarity by an angle of 5.05 (11)

S2. Experimental
The compound 4-(5-phenyl-1,3,4-oxadiazol-2-yl)pyridine (0.04 g, 0.18 mmol, synthesised by a previously reported method [Kangani et al. (2009)], and copper(II) chloride dihydrate (0.015 g, 0.09 mmol) were placed in the main arm of a branched tube. Methanol (13 ml) was carefully added to fill the arms, the tube was sealed and the reagent-containing arm supporting information sup-2 Acta Cryst. (2015). E71, m112-m113 immersed in an oil bath at 60 °C while the other arm was kept at ambient temperature. After two weeks, green, needle shaped crystals were deposited in the cooler arm. The crystals were filtered, washed with methanol and air dried. Yield 19% (7.0 mg).

S3. Refinement
All hydrogen atoms were positioned geometrically and treated as riding on their parent atoms (aromatic C-H = 0.95 Å, methyl C-H = 0.98 Å, U iso (H) = 1.2U eq (C, aromatic), U iso (H) = 1.5U eq (C, methyl)). The methyl group was allowed to rotate along the C-O bond to best fit the experimental electron density.

Figure 1
The molecular structure of the title compound (ellipsoids drawn at the 30% probability level). Symmetry code: i = 1 -x,y, 1 -z. Non-labelled non-hydrogen atoms have been generated by symmetry i.

Figure 2
The unit cell viewed along [100] (ellipsoids drawn at the 50% probability level). Intermolecular C-H···Cl and C-H···O contacts are indicated by dashed lines.