The crystal structures and Hirshfeld surface analyses of a cadmium(II) and a zinc(II) mononuclear complex of the new tetrakis-substituted pyrazine ligand ,','','''-[pyrazine-2,3,5,6-tetra-yltetra-kis-(methyl-ene)]tetra-kis-(-methyl-aniline).

The whole mol-ecule of the cadmium(II) complex, di-iodido-{,','','''-[pyrazine-2,3,5,6-tetra-yltetra-kis-(methyl-ene)]tetra-kis-(-methyl-aniline)-κ , , }cadmium(II), [CdI(CHN)], (), of the ligand ,','','''-[pyrazine-2,3,5,6-tetra-yltetra-kis-(methyl-ene)]tetra-kis-(-methyl-aniline) (), is generated by a twofold rotation symmetry; the twofold axis bis-ects the cadmium atom and the nitro-gen atoms of the pyrazine ring. The ligand coordinates in a mono-tridentate manner and the cadmium atom has a fivefold CdNI coordination environment with a distorted shape. In the zinc(II) complex, dichlorido{,','','''-[pyrazine-2,3,5,6-tetra-yltetra-kis-(methyl-ene)]tetra-kis-(-methyl-aniline)-κ , , }zinc(II) di-chloro-methane 0.6-solvate, [ZnCl(CHN)]·0.6CHCl, (), ligand also coordinates in a mono-tridentate manner and the zinc atom has a fivefold ZnNCl coordination environment with a distorted shape. It crystallized as a partial di-chloro-methane solvate. In the crystal of , the complex mol-ecules are linked by weak C-H⋯I contacts, forming ribbons propagating along [100]. In the crystal of , the complex mol-ecules are linked by a series of C-H⋯π inter-actions, forming layers lying parallel to the (11) plane. In the crystals of both compounds there are metal-halide⋯π(pyrazine) contacts present. The Hirshfeld analyses confirm the importance of the C-H⋯halide contacts in the crystal packing of both compounds.