Aromatic nitrile Phthalonitrile is a very important class of organic synthesis intermediates, widely found in pharmaceuticals, pesticides, herbicides, insecticides, dyes, fragrances and natural products. Chemicalbook, such as 2,4-dinitro-6-cyanoaniline, which can be used to make excellent bright blue diazo dye, and limonitrile with a sharp and strong lemon-like aroma, an international new nitrile spice, lemonnitrile, etc.