Thermal behaviour of copper(II) complexes of haloaspirinates

Complexes of Cu(II) with substituted o-acetoxy benzoic acids (5-haloaspirin es, X-asp) with and without pyridine (py), of composition [Cu-2(X-asp)(4)] and [Cu(X-asp)(2)(py)(2)] have been synthesized and characterized. Electron ic and vibrational spectroscopic data of these complexes are reported. Its thermal behaviour was investigated by thermogravimetry and differential the rmal analysis. In all complexes, the haloaspirinate ligands decompose in tw o or three steps, starting with the break up of the coordinated acetoxy gro ups. CuO is obtained as the final pyrolysis residue in all cases.