1-Naphthylamine, 99.0+%

1-Naphthylamine is an aromatic amine. It can be prepared by reducing 1-nitronaphthalene with iron and hydrochloric acid at about 70 °C, the reaction mixture being neutralized with milk of lime, and the naphthylamine stream-distilled. It may also be prepared, in the form of its acetyl derivative, by heating 1-naphthol with sodium acetate, ammonium chlorideand acetic acid; by heating 1-naphthol with calcium chloride-ammonia to 270 °C; and by heating pyromucic acid, aniline, zinc chloride and lime to 300 °C. It crystallizes in colorless needles which melt at 50 °C. It possesses a disagreeable odor, sublimes readily, and turns brown on exposure to air.

The 1-naphthylamine sulfonic acids are used for the preparation of azo dyes, these dyes possessing the important property of dyeing unmordanted cotton. The most important is naphthionic acid, 1-amino-4-sulfonic acid, produced by heating 1-naphthylamine and sulfuric acid to 170–180 °C with about 3% of crystallized oxalic acid. It forms small needles, very sparingly soluble in water. With diazotized benzidine it gives Congo red.