Synthesis and Characterization of Co(II), Ni(II), Cu(II) and Zn(II) Complexes with N'-( phenyl ( pyridin-2-yl)methylene)Nicotinohydrazide

The Schiff base (HL), derived from 2-benzoylpyridine and nicotinic hydrazide, and its complexes with some metal transition (Co, Ni, Cu, Zn) have been synthesized. These compounds have been characterized by means of elemental analysis, 1H and 13C NMR (for HL), FTIR spectroscopy, UV–Vis spectroscopy, molar conductance and room temperature magnetic measurements. The compounds are found isostructural and are formulated as {[Co(L)2].2H2O} (1), {[Ni(L)2].2H2O} (2). {[Cu(L)2].3H2O} (3). {[Zn(L)2].H2O} (4). The two ligand molecules act in their monodeprotonated forms through one azomethine nitrogen atom, one pyridine nitrogen atom and one iminolate oxygen atom yielding six coordinate metal center. The complex 4 crystallizes in the monoclinic space group P21 with cell parameters of a = 9.3429(8) A, b = 10.3034(9) A, c = 16.6349(14) A, β = 101.109(4)°, V = 1571.3(2) A3, Z = 2, R1 = 0.027, wR2 = 0.074. The zinc atom is six-coordinated, and the coordination polyhedron is best described as a distorted octahedral geometry. The aromatic rings of the ligand molecules are twisted each other with dihedral angle values in the range 10.168(2)°–74.430(1)°.