Syntheses, Crystal Structures and Spectroscopic Properties of Copper(II) and Nickel(II) Complexes with Oxime-Type Schiff Base Ligands

Two copperap and nickel(1) complexes, [Cu((I))(2)] (1) (HL1=1-(4-(((E)-3,5-dichloro-2-hydroxybenzylidene) amino)henyl)ethanoe O-benzyloxime) and [Ni (L-2)(2)] (2) (HL2=1-(4-(((E)-4-methoxy-2-hydroxybenzylidene)amino) phenyl)ethanone O-benzyloxime), have been synthesized and characterized by elemental analyses, IR and UV-Vis spectra and X-ray single crystal diffraction method. X-ray structure showed that complexes 1 and 2 have the similar structure, consisting of one metal ion, two ligand units. But the complex 1 crystallize in the monoclinic space group C2/c with the unit cell parameters: a=2.718 77(13) nm, b=1.321 99(6) nm, c=2.225 56(12) nm, beta=92.069 degrees (10); whereas the complex 2 crystallize in the monoclinic space group P2(1)/c, with the unit cell parameters: a=1.423 89(18) nm, b=0.601 22(8) nm, c=2.467 7(2) nm, beta=113.353(2)degrees. The center Cu(II) or Ni(II) atoms are all four-coordinated in a trans-N2O2 slightly distorted square-planar geometry by two phenoxy O atoms and two imine N atoms from two symmetry-related N,O-bidentate Schiff base ligands. And the supramolecular structures of the two complexes 1 and 2 are widely different by obvious intermolecular interaction. The complex 1 links some other molecules into an infinite 3D layer supramolecular structure via intermolecular C-H center dot center dot center dot pi and pi center dot center dot center dot pi interactions between neighboring benzene rings, while complex 2 formed 2D supramolecular channel structure by intermolecular C-H center dot center dot center dot pi hydrogen bond interactions. CCDC: 1560091, 1; 1560090, 2.