反应详情

12 g (0.05 mole) of 1-amino-4-naphthalenesulphonic acid, 7.2 ml of pyridine and 15 ml of acetic anhydride are placed in a flask provided with a stirrer and heater. The mixture is heated until the solution is clear, at which point 10 ml of absolute ethanol is added and the mixture is allowed to cool, first to ambient temperature and then in a refrigerator to 3° C. for 3 hours. The precipitate obtained is collected in a filter and is recrystallized in ethanol to give 11 g (Yield 59.4%) of pyridine N-acetyl-1-aminonaphthalene-4-sulphonate, having a m.p. of 172°-175° C. and whose IR spectrum (KBr) has the following bands: 3,400; 3,220; 1,640; 1,525; 1,370; 1,325; 1,200; 1,030; 850; 675; 635.

1. customprovided with a stirrer
2. temperatureThe mixture is heated until the solution
3. additionis added
4. customThe precipitate obtained
5. customis collected in
6. filtrationa filter
7. customis recrystallized in ethanol