Naphthol AS explained

Naphthol AS is an organic compound with the formula C₁₀H₆(OH)C(O)NHC₆H₅. It is the anilide of 3-hydroxy-2-carboxynaphthalene. Many analogous compounds are known, designated with a differing suffix. For example, in Naphthol AS-OL, the aryl substituent on nitrogen is C₆H₄-2-OCH₃. These compounds are used as coupling partners in the preparation of some azo dyes.^[1]

History

In 1911, it was found to be a good precursor to dyes for wool by chemists at K. Oehler Anilin- und Anilinfarbenfabrik Offenbach.^[2]

References

1. Encyclopedia: K. Hunger. W. Herbst. Pigments, Organic. Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH. Weinheim. 2012. 10.1002/14356007.a20_371. 978-3527306732.
2. Book: Willy Herbst, Klaus Hunger. Industrielle Organische Pigmente Herstellung, Eigenschaften, Anwendung. 2009 . 3. . Wiley VCH . 978-3-527-62496-6. 201.