200 mg (620 mmol) of perylene-3,4-dicarboxylic anhydride (prepared according to Example 20, below) are heated together with 250 mg (0.12 mmol) of 7-aminotridecane, 110 mg of zinc acetate dihydrate and 1.2 g of imidazole under an argon inert atmosphere at 135°-140° C. for 1 h. After cooling, the dark-red melt cake is digested with 100 ml of ethanol, and 100 ml of 15 per cent hydrochloric acid are added to the resulting suspension, and the mixture is boiled until all the ethanol has evaporated (the reaction product is readily soluble in ethanol). The solid is filtered off with suction and washed with warm water until the filtrate run-off no longer gives a yellow fluorescence. The crude product is then dried in a drying cabinet at 120° C. for 2 h and then chromatographed on silica gel using chloroform. The first coloured fraction is recrystallized by extraction with methanol. Yield 200 mg (63%) orange-red crystals showing strong solid fluorescence, m.p. 166°-168° C. Rf (chloroform/silica gel)=0.87. UV (CHCl3): λmax (ε)=506 (30250), 484 (31580). Fluorescence (CHCl3, exc. 506 nm) λmax (Irel): 540 (1), 568 (0.52).
