Preparation, Characterization and Biological Activities of some Unsymmetrical Schiff Bases Derived from m-phenyelenediamine and their Metal Complexes

Abstract

Unsymmetrical Schiff bases H2L1 = [ 1- (( E )-(( 3-((( E) -2- hydroxybenzylidene) amino)phenyl)imino)methyl) naphthalene-2-ol] and H2L2 = [1-((E)-((3-(((E)-1-(2-hydroxphenyl) ethylidene ) amino ) phenyl ) imino ) methyl ) naphthalene - 2 – ol ] which derived from m - phenylenediamine and 2-hydroxynaphthaldehyde and then with salicyaldehyde or 2- hydroxyacetophenone, and their complexes of the type [M 2Ln 2], where n = 1, 2 and M = Mn(II), Co(II), Ni(II) and Cu(II) have been synthesized. Adduct complexes of the type [M2Ln 2 (py)4] were also prepared in (1 : 4)(complex : py) molar ratio. The complexes and adducts were characterized by elemntal analysis (C. H. N), metal content, (IR, UV- v.s, 1H-NMR) spectroscopy, conductivity and magnetic measurements. The resulted data suggested that the Schiff bases containing ONNO donor atoms acts as dibasic tetradendetate ligands through coordinated with metal ions. Conductivity data in DMSO solution showed that all complexes are non- electrolyte. Magnetic moment and electronic spectra data indicat that the complexes have either tetrahedral or octahedral geometry while [Ni2 Ln 2] complexes have square planer geometry. The legends and their complexes were screened for antibacterial activity against Staphylococcus- aureus and Escherichia coli. The ligands and their complexes showed some biological activities .