Synthesis, spectral, magnetic, thermal and biological aspects of pyromellitic dianhydride based co-ordination polymers

A ligand, 2, 5-bis (4-nitrophenylcarbamoyl) terephthalic acid (bnpctpa) was synthesized by using dianhydride of 1, 2, 4, 5-benzenetetracarboxylic (pyromellitic dianhydride–abbreviated PMDA) with 4-nitro aniline. Novel Co-ordination polymers of this bis-ligand were prepared with Cu(II), Ni(II), Co(II), Mn(II) and Zn(II) metal salts. The co-ordination polymers and parent ligand were characterized by elemental analysis, spectral studies, thermogravimetry, number-average molecular weights (Mn), diffuse reflectance spectral studies and magnetic susceptibilities. The biological activity of all the samples has also been monitored against plant pathogens.