HIGHLY PHOTOSTABLE ORGANIC FLUORESCENT PIGMENTS - A SIMPLE SYNTHESIS OF N-ARYLPYRROLOPYRROLEDIONES (DPP)

N-Arylpyrrolopyrrolediones 1b-g are prepared by the condensation of th e corresponding lactones 2 and 5 with arylamines in the presence of di cyclohexylcarbodiimide. Bright red dye pigments are obtained with an i ntense red to orange solid-state fluorescence.