SYNTHESIS OF 1-BENZOTRIAZOLYLACETYL-5-HYDROXY-3-METHYL-5-PHENYL-2-PYRAZOLINES AND THEIR TRANSITION METAL COMPLEXES

ABSTRACT

1-(1H-Benzotriazol-1-acetyl)-5-hydroxy-3-methyl-5-phenyl-2-pyrazoline (H₂L¹) and 1-(2H-benzotriazol-2-acetyl)-5-hydroxy-3-methyl-5-phenyl-2-pyrazoline (H₂L²) have been synthesized by condensing 1H-benzotriazol-1-acetic acid hydrazide or 2H-benzotriazol-2-acetic acid hydrazide with 1-phenyl-1,3-butanedione. Complexes of the type [ML]₂ and [M(HL)(AcO)] [M=Zn(II), Cu(II), Ni(II)] have been prepared by refluxing the pyrazolines with the metal acetate hydrates in ethanol. The ligands and their complexes have been characterized by elemental analyses, IR, ¹H NMR and MS spectra. The spectra show that the ligands H₂L¹ and H₂L² coordinate as tridentate ligands through the enolic oxygens and the nitrogen of the azomethine group with opening of the pyrazoline rings.

Acknowledgment

The work was supported by the Gansu Province Funds of Naturals Sciences.