0.70 g (2.17 mmol) of perylene-3,4-dicarboxylic anhydride is mixed with 0.49 g (3.28 mmol) of 4-t-butylaniline, 3.00 g of imidazole and 0.10 g of zinc acetate dihydrate and the mixture is heated at 140°-150° C. for 5 h. While still hot, the mixture is treated with 100 ml of ethanol, and then 200 ml of 10% hydrochloric acid are added. The red suspension is heated until all the ethanol has evaporated, and the product is then filtered off with suction. The red-brown residue is boiled in 10% potassium carbonate solution, the solid residue is filtered off with suction while hot and rinsed several times with hot dist. water. The red residue is dried in a drying cabinet at 120° C. and then recrystallized by extraction with a toluene/methanol mixture to give 0.80 g (81%) of red N-(4-t-butylphenyl)perylene-3,4-dicarboximide which shows a red solid fluorescence. M.p. >330° C. Rf (CHCl3 /silica gel)=0.35.
