1243725-16-7Relevant academic research and scientific papers
Cobalt(II) complexes of 4-(1-H-1,3-benzimidazole-2-yl)-1,5-dimethyl-2- phenyl-1-2-dihydro-3-H-pyrazol-3-one incorporating various anions: Synthesis, characterization and crystal structures
Kumar, P. M. Vimal,Radhakrishnan
, p. 2335 - 2344 (2010/09/06)
The structure of 4-(1-H-1,3-benzimidazole-2-yl)-1,5-dimethyl-2-phenyl-1-2- dihydro-3-H-pyrazol-3-one (Opdac) derived from the condensation of O-phenylenediamine and 4-antipyrine carboxaldehyde has been confirmed by X-ray crystallography. The free ligand, Opdac, crystallizes into a triclinic lattice with the space group P1?. Reaction of Opdac with salts of Co(II) affords five novel mononuclear complexes [Co(Opdac)Cl2] (1), [Co(Opdac)Br2] (2), [Co(Opdac)[2] (3), [Co(Opdac) 2NO3]NO3 (4) and [Co(Opdac)2ClO 4]-ClO4 (5). All the reaction products were characterized by a variety of physicochemical techniques, viz. elemental analysis, molar conductivity, CHNS analysis, magnetic susceptibility measurements and spectroscopic studies. The solid-state structures of complexes 1, 2 and 4 were established by Single Crystal X-ray crystallography. The complex 1 crystallize in the monoclinic space group C2/c, where as complex 2 crystallizes in the orthorhombic space group Pbca. In complexes 1 and 2, the ratio of metal to ligand is 1:1 and both the anions are coordinated to the metal ion, in which central metal ion adopts a distorted tetrahedral geometry. The mononuclear units in 1 and 2 are engaged in weak intermolecular C-H?X and N-H?X (X = Cl or Br) hydrogen bonds to give a 2D structure. The complex 4 crystallized in monoclinic space group C2/c forming six membered chelate ring. The structural analysis show that Co(II) ion in 4 adopts a distorted octahedral geometry with a CoN2O2 chromophore, ligated through two imine nitrogen and two pyrazolone oxygen atoms from two Opdac units; the hexacoordination is completed by O atom of the nitrate ion in a bidentate fashion. The hydrogen gas sorption isotherms at 77 K confirmed the permanent porosities of the complex 1.
