Product Name: Acid Orange 7
Synonyms: Orange II sodium salt, Biological stain;DAIDAI205;ORANGE 4;ORANGE II, FOR MICROSCOPY;ORANGE II SODIUM;ORANGE II, CERTIFIED;OrangeIiC.I.15510;Orange 86
CAS: 633-96-5
MF: C16H11N2NaO4S
MW: 350.32
EINECS: 211-199-0
Product Categories: Organics;Azo
Mol File: 633-96-5.mol

Acid Orange 7 Chemical Properties
Melting point  164°C
solubility  Solubility Very soluble in water; very slightly soluble in ethanol
pka 8.26, 11.4(at 25℃)
Colour Index  15510
form  Crystalline Powder
color  Green to blue
Odor Odorless
PH Range Amber (7.4) to orange (8.6);Orange (10.2) to red (11.8)
Water Solubility  116 g/L (30 ºC)
λmax 483nm
Merck  14,6858
BRN  3898201
Biological Applications Cosmetics; wound dressing materials
Major Application Organic light emitting diodes (OLEDs), nanoparticles, inks, wood preservatives, textiles, hair dyes, cosmetics, wound dressing materials, biofuel cells
CAS DataBase Reference 633-96-5(CAS DataBase Reference)
EPA Substance Registry System C.I. Acid Orange 7, monosodium salt (633-96-5)
Safety Information
Hazard Codes  Xi
Risk Statements  36/37/38
Safety Statements  26-36-37/39
WGK Germany  3
RTECS  DB7084000
HS Code  32041200

Acid Orange 7 Usage And Synthesis
Chemical Properties Orange-red powder
Purification Methods Purification is as for Orange I. Its solubility in H2O is 40g/L at 25o. [Müller et al. Helv Chim Acta 35 2579 1952.] Also purify it by extracting it with a small volume of cold water, then crystallising it by dissolving in boiling water, cooling to ca 80o, adding two volumes of EtOH and cooling. When cold, the precipitate is filtered off, washed with a little EtOH and dried in air. It can be salted out from aqueous solution with sodium acetate, then repeatedly extracted with EtOH. Meggy and Sims [J Chem Soc 2940 1956], after crystallising the sodium salt twice from water, dissolved it in cold water (11mL/g) and added conc HCl to precipitate the acid dye which was separated by centrifugation, redissolved and again precipitated with acid. After washing the precipitate three times with 0.5M acid, it was dried over NaOH, recrystallised twice from absolute EtOH, washed with a little Et2O, dried over NaOH and stored over conc H2SO4 in the dark. It can then be converted to the pure salt with the calculated amount of NaOH or Na2CO3.

Product Name: Acid Orange 7
Synonyms: Orange II sodium salt, Biological stain;DAIDAI205;ORANGE 4;ORANGE II, FOR MICROSCOPY;ORANGE II SODIUM;ORANGE II, CERTIFIED;OrangeIiC.I.15510;Orange 86
CAS: 633-96-5
MF: C16H11N2NaO4S
MW: 350.32
EINECS: 211-199-0
Product Categories: Organics;Azo
Mol File: 633-96-5.mol

Acid Orange 7 Chemical Properties
Melting point  164°C
solubility  Solubility Very soluble in water; very slightly soluble in ethanol
pka 8.26, 11.4(at 25℃)
Colour Index  15510
form  Crystalline Powder
color  Green to blue
Odor Odorless
PH Range Amber (7.4) to orange (8.6);Orange (10.2) to red (11.8)
Water Solubility  116 g/L (30 ºC)
λmax 483nm
Merck  14,6858
BRN  3898201
Biological Applications Cosmetics; wound dressing materials
Major Application Organic light emitting diodes (OLEDs), nanoparticles, inks, wood preservatives, textiles, hair dyes, cosmetics, wound dressing materials, biofuel cells
CAS DataBase Reference 633-96-5(CAS DataBase Reference)
EPA Substance Registry System C.I. Acid Orange 7, monosodium salt (633-96-5)
Safety Information
Hazard Codes  Xi
Risk Statements  36/37/38
Safety Statements  26-36-37/39
WGK Germany  3
RTECS  DB7084000
HS Code  32041200

Acid Orange 7 Usage And Synthesis
Chemical Properties Orange-red powder
Purification Methods Purification is as for Orange I. Its solubility in H2O is 40g/L at 25o. [Müller et al. Helv Chim Acta 35 2579 1952.] Also purify it by extracting it with a small volume of cold water, then crystallising it by dissolving in boiling water, cooling to ca 80o, adding two volumes of EtOH and cooling. When cold, the precipitate is filtered off, washed with a little EtOH and dried in air. It can be salted out from aqueous solution with sodium acetate, then repeatedly extracted with EtOH. Meggy and Sims [J Chem Soc 2940 1956], after crystallising the sodium salt twice from water, dissolved it in cold water (11mL/g) and added conc HCl to precipitate the acid dye which was separated by centrifugation, redissolved and again precipitated with acid. After washing the precipitate three times with 0.5M acid, it was dried over NaOH, recrystallised twice from absolute EtOH, washed with a little Et2O, dried over NaOH and stored over conc H2SO4 in the dark. It can then be converted to the pure salt with the calculated amount of NaOH or Na2CO3.