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

摘要

1-(1H-Benzotriazol-1-acetyl)-5-hydroxy-3-methyl-5-phenyl-2-pyrazoline (H_2L~1) and 1-(2H-benzotriazol-acetyl)-5-hydroxy-3-methyl-5-phenyl-2-pyrazoline (H_2L~2) have been synthesized by condensing 1H-benzotriazol-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 H_2L~1 and H_2L~2 coordinate as tridentate ligands through the enolic oxygens and the nitrogen of the azomethine group with opening of the pyrazoline rings.