Microwave-assisted synthesis of mixed ligand complexes of Zn(II), Cd(II) and Hg(II) derived from 4-aminopyridine and nitrite ion: Spectral, thermal and biological investigations

Zn(II), Cd(II) and Hg(II) complexes with a general composition[M(L) 2(X)2], where L=4-aminopyridine (4AP) and X=NO2-were prepared under microwave irradiation. The metal complexes were characterized by elemental analyses, molar conductance, IR, Far-IR, electronic, NMR ( 1H, 13C), XPS spectral and thermal studies. The spectroscopic studies reveal the composition, different modes of bonding, electronic transition, different chemical environment of C and H atoms and the electronic state of the metal atoms. On the basis of the characterization data, tetrahedral geometry is suggested for all the complexes. The free ligand (4-aminopyridine) and their metal complexes were screened against phytopathogenic fungi and bacteria in vitro and the activities were compared.