Synthesis and characterization of new 5-(o-substituted arylazo)-barbituric acid complexes with transition metals

The synthesis of new 5-(o-substituted arylazo)barbituric acid iron(III), cobalt(II), nickel(II) and copper(II) complexes is reported. Electronic spectral data, magnetic moment and e.s.r. measurements were recorded in order to elucidate their geometry and mode of bonding (i.r. evidence). The complexes are non-electrolytes.