New conjugated azomethine oligomers obtained from bis-(hydroxyphenyl)methylenediamine via oxidative polycondensation and their complexes with metals


KAYA İ. , Bilici A., Sacak M.

SYNTHETIC METALS, vol.159, no.14, pp.1414-1421, 2009 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 159 Issue: 14
  • Publication Date: 2009
  • Doi Number: 10.1016/j.synthmet.2009.03.014
  • Title of Journal : SYNTHETIC METALS
  • Page Numbers: pp.1414-1421

Abstract

A new conjugated aromatic oligo(azomethine) derivative was synthesized by oxidative polycondensation of 1,4-bis[(2-hydroxyphenyl)methylene]phenylenediamine (HPMPDA) by air, H2O2 and NaOCl oxidants in an aqueous alkaline medium. The structures of 1,4-bis[(2-hydroxyphenyl)methylene]phenylenediamine and oligo-1,4-bis[(2-hydroxyphenyl)methylene]phenylenediamine (OHPMPDA) were confirmed by FT-IR, UV-vis, H-1 NMR, C-13 NMR and elemental analysis. The characterization was made by TGA-DTA, size exclusion chromatography (SEC), magnetic moment and solubility tests. The H-1 NMR and C-13 NMR data showed that the polymerization was proceeded by C-C coupling according to ortho and para positions of -OH group of 1,4-bis[(2-hydroxyphenyl)methylene]phenylenediamine. Metal complex compounds of OHPMPDA were synthesized with metal salts of Fe, Co, Ni, Cu, Zn, Cd, Mn, Cr, Pb and Hg. Elemental analyses of oligomer-metal complexes suggested that the ratio of metal to oligomer is 1:1. Thermal stabilities of the oligomer-metal complexes were determined by thermogravimetric analyses (TGA). According to TG analyses, oligomer-metal complexes were fairly stable against temperature and thermal decomposition. Also, electrical conductivities of OHPMPDA and oligomer-metal complexes were measured by four-point technique. The results of this study showed that aromatic oligoazomethine and its metal complexes were an interesting class of conjugated compounds of which electronic structure and the other properties can be regulated over a wide range by using different oxidation reagents. (C) 2009 Elsevier B.V. All rights reserved.