Synthesis of iron(III), cobalt(II), nickel(II), copper(II) and zinc(II) complexes with new quadridentate N, O~ donor ligands

The reaction between anthranilic acid and oxalyl chloride/malonyl chloride results in new quadridentate ligands, bis(2-carboxyphenyl)oxamide [CPOA]/bis(2-carboxyphenyl)malonamide [CPMA]. These ligands form 1 : 1 complexes of general formula. [Fe(L)(H20)2)CI, [M(L] and [Zn(L)].2H20, where L = CPOA or CPMA, M = Co", Ni" or Cu".