Synthesis and characterization of manganese(II), cobalt(II), nickei(Il), and copper(II) complexes of Schiff base derivatives of dehydroacetic acid

Abstract

The solid complexes of Mn(II), Co(II), Ni(II) and Cu(II) with the Schiff bases derived from 3-acetyl-6-methyl-(2H)-pyran- 2,4(3H) dione (dehydroacetic acid) and aniline, <i>p</i>-chloroaniline, <i>p-</i>iodoaniline and <i>p</i>-phenetidine have been prepared and characterised

by elemental analysis, conductance, magnetic, thermal, IR, UV/visible and NMR spectral studies. The ligand field parameters have been evaluated for Co(II), Ni(II) and Cu(II) complexes which suggest an octahedral geometry for each of them. The elemental analysis, magnetic moment and spectral data suggest the dimeric nature of Mn(II) complexes, with octahedral geometry. The fungicidal activities of the ligand and their metal complexes

have been screened <i>in vitro </i>against <i>Aspergillus niger </i>and the percentage inhibition of the metal complexes is found to be increased considerably than that of their corresponding ligands and the order is Cu > Ni > Mn >Co.