p-Nitroaniline: Acetanilide Nitrated, then Steamed

p-Nitroaniline is the diazo half of Para Red. Thorpe (1912) gives the works method: nitrate acetanilide in sulphuric acid at 40 to 50 °C, drown it in hot water, steam off the acetyl groups, and separate the two nitroanilines: the ortho comes down on ice, the para when soda lye is added. Yields about 60 % para, 25 % ortho. Our batch is the works batch in grams instead of kilos. Strong acids: goggles, gloves, face shield. The picture: our own drawing.