Cu(II) and Ni(II) Complexes of Novel Three 2-{1′-Phenyl-3′-(4^″-Halophenyl)-1H-Pyrazole-4-yl}-1H-Benzimidazoles: Synthesis and Structural Depiction

Abstract

Novel three 2-{1′-Phenyl-3′-(4^″-halophenyl)-1H-pyrazole-4-yl}-1H-benzimidazoles (HB_a–c) synthesized by the condensation of o-phenylenediamine and substituted-1H-pyrazole aldehydes in the presence of H₂O₂ through Ceric ammonium nitrate in catalytic amount and the nonchelated monodentate benzimidazoles complexes of 2-{1′-Phenyl-3′-(4^″-halophenyl)-1H-pyrazole-4-yl}-1H-benzimidazoles were synthesized with a choice of metal salts in 2:1 mole ratio of ligand and metal salts, respectively, in ethanolic solution. The confirmed structures and characteristics of complexes were in good agreement with various physicochemical studies. The monodentate behavior of the ligands was proposed on the basis of spectral studies. The newly synthesized complexes possess octahedral and tetrahedral, square pyramidal and square planar geometry.

Keywords:

• Cu(II) and Ni(II) complexes
• monodentate 1H-benzimidazole ligands
• physicochemical studies
• pyrazole aldehydes