Naphthionic acid

Naphthionic acid

Names
IUPAC name 4-aminonaphthalene-1-sulfonic acid
Other names Piria's acid
Identifiers
CAS Number	84-86-6
3D model (Jmol)	Interactive image
ChEBI	CHEBI:38219
ChemSpider	6532
ECHA InfoCard	100.001.425
EC Number	201-567-9
PubChem	6790
InChI 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
SMILES c1ccc2c(c1)c(ccc2S(=O)(=O)O)N
Properties
Chemical formula	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).
Infobox references

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]

References

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.