Two dimensional heteropolynuclear Zn(II) and Cd(II)-tetracyanopalladate(II) complexes with the 1-ethylimidazole ligand exhibiting C–H⋯Pd interactions

The cyano-bridged heteronuclear complexes [Zn(etim)2Pd(μ-CN)4]n (1) and [Cd(etim)2Pd(μ-CN)4]n (2) (etim = 1-ethylimidazole), have been synthesized and characterized by FT-IR, Raman spectroscopy, thermal and elemental analyses. The crystal structures of the complexes have been determined by X-ray single crystal diffraction. In the complexes, the Pd(II) ion is coordinated by four cyano ligands, forming a square-planar geometry, and the Zn(II) or Cd(II) ions are coordinated by six N atoms from four bridging cyano ligands and two etim ligands in a distorted octahedral geometry. The most important features of the complexes are the presence of C–H···Pd hydrogen-bonding interactions between the Pd(II) ion and the hydrogen atoms of the etim ligand.

The cyano-bridged heteronuclear complexes, [M(etim)2Pd(μ-CN)4]n (where, M = ZnII (1) or CdII (2); etim = 1-ethylimidazole), have been synthesized and characterized by FT-IR, Raman spectroscopy, thermal and elemental analyses. The most striking feature of the complexes is the presence of C–H⋯M hydrogen-bonding interactions between the Pd(II) ion and hydrogen atoms of the etim ligands. These weak hydrogen bonds play an important role in the construction of the supramolecular structure. Adjacent 2D layers are further extended into a three-dimensional supramolecular framework by weak C–H⋯Pd hydrogen bonding interactions.Figure optionsDownload as PowerPoint slide