Spectroscopic and thermal studies on solid complexes of 4-(2-pyridylazo) resorcinol with some transition metals

The preparation and characterization of Mn-II, Fe-II, Co-II, Ni-II, Cu-II, Zn-II and Cd-II chelates of 4-(2-pyridylazo) resorcinol, H2L ( PAR) were reported. The solid complexes were characterized by elemental and thermal analyses, IR, molar conductance, magnetic measurements. All complexes were found to have the formulae [M(HL)(2)]. The 1:2 (M :L) complexes showed octahedral geometry around M-II. The molar conductance data reveal that the chelates are non- electrolytes. IR spectra show that the ligand is coordinated to the metal ions in a terdentate manner and complexation with 4-(2-pyridylazo) resorcinol through the resorcinol OH, azo N and pyridyl N. In particular, the thermal decomposition of all the complexes of PAR is studied in nitrogen atmosphere. The final decomposition products are found to be the corresponding metal or metal oxides.