Nine new tetracyanometallate(II) complexes with 2-(2-aminoethyl)pyridine: synthesis, crystal structures and spectroscopic studies

Abstract

Nine new cyanide complexes, {[Cu(aepy)2M(µ-CN)(CN)3]⋅2H2O}n [M(II) = Ni (1), Pd (2) or Pt (3)], [Zn(aepy)2M(µ-CN)(CN)3]n [M = Ni (4), Pd (5) or Pt (6)] and [Cd(aepy)2M(µ-CN)(CN)3]n [M(II) = Ni (7) or Pd (8)] and (Haepy)2[Pt(CN)4] (9) (aepy = 2-(2-aminoethyl)pyridine), were synthesized and characterized structurally using single crystal X-ray diffraction, vibrational spectroscopy, thermal and elemental analyses. The structure analyses revealed that cyanide complexes 1–3 for Cu(II) and 4–6 for Zn(II) are heterobinuclear clusters, whereas the two Cd(II) complexes 7 and 8 are infinite one-dimensional coordination polymers. In heterometallic complexes 7 and 8, the Cd(II) ions are located on a center of symmetry and are coordinated by two nitrogens from cyanide ligands and four nitrogens from aepy ligands, thus showing a distorted octahedral geometry. In 1–9, the intermolecular N–H⋅⋅⋅N hydrogen bonds or/and C–H⋅⋅⋅M interactions (M = Ni(II), Pd(II) and Pt(II)) generate 3D supramolecular networks.