Synthesis and characterization of an unsymmetrical diimide-disulfonato phthalocyaninatozinc dipotassium salt

An unsymmetrical diimide-disulfonato phthalocyanatozinc dipotassium salt was first synthesized by direct condensation of 1,2,4,5-tetracarboxylicbenzene with 4-sulfophthalic acid mono-potassium salt. Then, the condensed product was separated by reverse HPLC method and further purified by a membrane separation method. The structure of the title isomer was characterized by UV/Vis, IR, elemental analysis as well as 1H NMR.