Naphthionic acid is an organic compound with the formula C10H6(SO3H)(NH2). It is one of several aminonaphthalenesulfonic acids, derivatives of naphthalene containing both amine and sulfonic acid functional groups. It is a white solid, although commercial samples can appear gray.[1] It is used in the synthesis of azo dyes such as Rocceline (a. k. a. Solid Red A), during which the amino group of the acid (in the form of a salt) is diazotated and then coupled with, in the case mentioned, β-naphthol. It is prepared by treating 1-aminonaphthalene with sulfuric acid.[2]

Naphthionic acid
Names
Preferred IUPAC name
4-Aminonaphthalene-1-sulfonic acid
Other names
Piria's acid
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.001.425 Edit this at Wikidata
EC Number
  • 201-567-9
UNII
  • InChI=1S/C10H9NO3S/c11-9-5-6-10(15(12,13)14)8-4-2-1-3-7(8)9/h1-6H,11H2,(H,12,13,14)
    Key: NRZRRZAVMCAKEP-UHFFFAOYSA-N
  • InChI=1/C10H9NO3S/c11-9-5-6-10(15(12,13)14)8-4-2-1-3-7(8)9/h1-6H,11H2,(H,12,13,14)
    Key: NRZRRZAVMCAKEP-UHFFFAOYAN
  • c1ccc2c(c1)c(ccc2S(=O)(=O)O)N
Properties
C10H9NO3S
Molar mass 223.24
Appearance white solid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

References

edit
  1. ^ 4-Amino-1-naphthalenesulfonic acid; MSDS No. 250619; Sigma–Aldrich Chemie GmbH: Steinheim, 29 Dec 2011.
  2. ^ Gerald Booth "Naphthalene Derivatives" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. doi:10.1002/14356007.a17_009.