Chrysoine resorcinol

Chrysoine resorcinol
Skeletal formula of chrysoine resorcinol as a sodium salt
Space-filling model of chrysoine resorcinol as a sodium salt
Names
IUPAC name
Sodium 4-[(2,4-dihydroxyphenyl)diazenyl]benzenesulfonate
Other names
Sodium p-(2,4-dihydroxyphenylazo)benzenesulfonate; Chrysoine; Resorcinol Yellow; Gold Yellow; Yellow T; Tropaeolin O; Tropaeolin R; C.I. Food Yellow 8; C.I. Acid Orange 6; C.I. 14270
Identifiers
CAS Number
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.008.114
EC Number
  • 208-924-8
PubChem CID
UNII
CompTox Dashboard (EPA)
InChI
  • InChI=1S/C12H10N2O5S.C6H6O2.Na/c15-9-3-6-11(12(16)7-9)14-13-8-1-4-10(5-2-8)20(17,18)19;7-5-2-1-3-6(8)4-5;/h1-7,15-16H,(H,17,18,19);1-4,7-8H;/q;;+1/p-1/b14-13+;; checkY
    Key: DJYSHZPRWDNEOL-QDBORUFSSA-M checkY
  • InChI=1/C12H10N2O5S.Na/c15-9-3-6-11(12(16)7-9)14-13-8-1-4-10(5-2-8)20(17,18)19;/h1-7,15-16H,(H,17,18,19);/q;+1/p-1/b14-13+;
    Key: COEZWFYORILMOM-WTMITFMSBV
  • InChI=1/C12H10N2O5S.C6H6O2.Na/c15-9-3-6-11(12(16)7-9)14-13-8-1-4-10(5-2-8)20(17,18)19;7-5-2-1-3-6(8)4-5;/h1-7,15-16H,(H,17,18,19);1-4,7-8H;/q;;+1/p-1/b14-13+;;
    Key: DJYSHZPRWDNEOL-MNMGBGISBV
SMILES
  • [Na+].Oc2cc(O)ccc2/N=N/c1ccc(cc1)S([O-])(=O)=O
  • [Na+].Oc2cc(O)ccc2/N=N/c1ccc(cc1)S([O-])(=O)=O.Oc1cccc(O)c1
Properties
Chemical formula
C12H9N2NaO5S
Molar mass 316.26 g·mol−1
Appearance Orange-yellow solid
Solubility in water
Partially soluble
Hazards
NFPA 704 (fire diamond)
NFPA 704 four-colored diamond
2
1
0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)
Infobox references

Chrysoine resorcinol is a synthetic azo dye which was formerly used as a food additive. In Europe, it was banned as a food additive in 1977.[1] In the US, it was banned in 1988.[2]

Chrysoine resorcinol can be used as a pH indicator with a color change between pH 11 and pH 12.7. In colorimetry, it has an absorption maximum of 387 nm.

Chrysoine resorcinol (pH indicator)
below pH 11.0 above pH 12.7
11.0 12.7

Preparation

Acid orange 6 can be synthesised via the azo coupling of sulfanilic acid and resorcinol,

Notes

  1. ^ "EUR-Lex - Official Journal of the European Union".
  2. ^ "Chrysoine Resorcinol Properties, Molecular Formula, Applications - WorldOfChemicals". www.worldofchemicals.com. Retrieved 2022-07-12.