The crystal structures and Hirshfeld surface analyses of a cadmium(II) and a zinc(II) mononuclear complex of the new tetrakis-substituted pyrazine ligand N, N′, N′′, N′′′-[pyrazine-2,3,5,6-tetra­yltetra­kis­(methyl­ene)]tetra­kis­( N-methyl­aniline)

Abstract

In the cadmium(II) and zinc(II) complexes of the tetra­kis-substituted pyrazine ligand, N, N′, N′′, N′′′-[pyrazine-2,3,5,6-tetra­yltetra­kis­(methyl­ene)]tetra­kis­( N-methyl­aniline), the ligand coordinates in a mono-tridentate fashion, and both metal atoms have fivefold coordination spheres with distorted shapes.

Abstract

The whole mol­ecule of the cadmium(II) complex, di­iodido­{ N, N′, N′′, N′′′-[pyrazine-2,3,5,6-tetra­yltetra­kis­(methyl­ene)]tetra­kis­( N-methyl­aniline)-κ ³ N ², N ¹, N ⁶}cadmium(II), [CdI ₂(C ₃₆H ₄₀N ₆)], ( I), of the ligand N, N′, N′′, N′′′-[pyrazine-2,3,5,6-tetra­yltetra­kis­(methyl­ene)]tetra­kis­( N-methyl­aniline) ( L), is generated by a twofold rotation symmetry; the twofold axis bis­ects the cadmium atom and the nitro­gen atoms of the pyrazine ring. The ligand coordinates in a mono-tridentate manner and the cadmium atom has a fivefold CdN ₃I ₂ coordination environment with a distorted shape. In the zinc(II) complex, dichlorido{ N, N′, N′′, N′′′-[pyrazine-2,3,5,6-tetra­yltetra­kis­(methyl­ene)]tetra­kis­( N-methyl­aniline)-κ ³ N ², N ¹, N ⁶}zinc(II) di­chloro­methane 0.6-solvate, [ZnCl ₂(C ₃₆H ₄₀N ₆)]·0.6CH ₂Cl ₂, ( II), ligand L also coordinates in a mono-tridentate manner and the zinc atom has a fivefold ZnN ₃Cl ₂ coordination environment with a distorted shape. It crystallized as a partial di­chloro­methane solvate. In the crystal of I, the complex mol­ecules are linked by weak C—H⋯I contacts, forming ribbons propagating along [100]. In the crystal of II, the complex mol­ecules are linked by a series of C—H⋯π inter­actions, forming layers lying parallel to the (1 1) 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.