| Popis: |
A series of benzimidazolone and phthalimide derivatives has been synthesized. 2-Amino-5-nitrohenzonitrile was hydrolyzed during its diazotization with nitrosoylsulfuric acid at 70°C to give the diazonium salt of 2-carboamoyl-4-nitroaniline. A series of yellow and red pigments was prepared and their m.p., temperature of color change and TGA determined. The presence of cyano, amide, chloro and methoxy groups improved the thermal stability; methylation of the -NHCONH- and -CONHCO- groups had an adverse effect on the thermal stability, the decomposition temperature being lowered. |
