Synthesis, spectral and single crystal X-ray diffraction studies on Mn(II), Ni(II), Cu(II) and Zn(II) complexes with 2-hydroxy-benzoic acid (phenyl-pyridin-2-yl-methylene)-hydrazide

Abstract

The ligand 2-hydroxy-benzoic acid (phenyl-pyridin-2-yl-methylene)-hydrazide (Hbpph) and its Mn(II), Ni(II), Cu(II) and Zn(II) complexes have been synthesized. The metal complexes are characterized by elemental analyses, molar conductance, magnetic susceptibility measurements, electronic, IR and NMR spectral techniques. The molecular structures of the ligand and metal complexes have been determined by single crystal X-ray diffraction studies. Hbpph acts as monobasic tridentate ligand and coordinates through pyridyl-N, azomethine-N and enolate-O with metal ion. Magnetic moments and electronic spectral studies of Mn(II), Ni(II) and Cu(II) complexes suggest a high spin six−coordinate geometry around metal ion. Single crystal structure of the ligand molecule displays a Z molecular conformation about the >CN– bond, whereas, the metal complexes exhibit E-configuration. The molecular structures of the metal complexes are stabilized by various H-bonding and C–H⋯π interactions.