Palladium complexes of NO type Schiff bases: synthesis, characterization and antioxidant activities

The reaction of o-aminophenol with para hydroxy and methoxy substituted benzaldehydes yielded two Schiff bases. These Schiff bases functioning precursors were turned into palladium complexes by treating palladium acetate. The structural formulas based on spectral methods (elemental analysis, FT-IR spectroscopy, NMR spectroscopy and QTOF-LC/MS spectroscopy) were suggested for obtained both complexes. According to the structural characterization methods, one of the complexes had also an acetate co-ligand along with the hydroxy substituted Schiff base ligand. In the other complex, the palladium central ion was proposed to be coordinated with two methoxy substituted Schiff bases. Besides, DPPH scavenging activities of the all synthesized compounds were determined and compared to well-known antioxidant standards. According to the results, antioxidant activities of the palladium complexes was mild but lower than parent Schiff bases.