523-44-4

Basic information

• Product Name: ORANGE I
• Synonyms: 1333orange;4-((4-hydroxy-1-naphthalenyl)azo)benzenesulfonicacid,monosodiumsalt;4-((4-hydroxy-1-naphthalenyl)azo)-benzenesulfonicacimonosodiumsalt;4-((4-hydroxy-1-naphthalenyl)azo)benzenesulphonicacid,monosodiumsalt;4-[(4-hydroxy-1-naphthalenyl)azo]-benzenesulfonicacimonosodiumsalt;4-p-sulfophenylazo-1-naphtholmonosodiumsalt;4-p-sulphophenylazo-1-naphthol,monosodiumsalt;a.f.orangeno.1
• CAS NO: 523-44-4
• Molecular Formula: C₁₆H₁₁N₂O₄S*Na
• Molecular Weight: 350.32
• EINECS: 208-346-6
• Product Categories: Organics
• Mol File: 523-44-4.mol
• Article Data: 1

Chemical Properties

• Melting Point: 260 °C (decomp)
• Appearance: /
• Storage Temp.: Inert atmosphere,Room Temperature
• Solubility: DMSO (Slightly), Methanol (Slightly)
• Merck: 14,6857
• BRN: 3826844
• CAS DataBase Reference: ORANGE I(CAS DataBase Reference)
• NIST Chemistry Reference: ORANGE I(523-44-4)
• EPA Substance Registry System: ORANGE I(523-44-4)

Safety Data

• Safety Statements: 22-24/25
• WGK Germany: 3
• RTECS: DB7085000
• Hazardous Substances Data: 523-44-4(Hazardous Substances Data)

Usage

Chemical Properties

Crystalline

Preparation

4-Aminobenzenesulfonic acid diazo, and Naphthalen-1-ol?coupling.

Properties and Applications

orange. Soluble in water for palm light orange, slightly soluble in ethanol, acetone, insoluble in most organic solvents. The strong sulfuric acid for purple, diluted into palm orange, red with purple precipitation. Its water solution to join strong hydrochloric acid for orange brown; Add sodium hydroxide in red. Used for wool, silk fiber dyeing, etc. Also used in leather dyeing and indicator.

Purification Methods

Purify the dye by dissolving it in the minimum volume of H2O, adding, with stirring, a large excess of EtOH. The salt separates as orange needles. It is collected by centrifugation or filtration, washed with absolute EtOH (3x) and Et2O (2x) in the same way and dried in a vacuum desiccator over KOH. The free acid can be recrystallised from EtOH. [Slotta & Franke Chem Ber 64 86 1931, Beilstein 16 H 275, 16 II 117, 16 IV 410.] The purity can be checked by titration with titanium chloride [Klotz J Am Chem Soc 68 2299 1946].

InChI:InChI=1/C16H12N2O4S.Na/c19-16-10-9-15(13-3-1-2-4-14(13)16)18-17-11-5-7-12(8-6-11)23(20,21)22;/h1-10,19H,(H,20,21,22);/q;+1/p-1/b18-17+;

Upstream product

• 90-15-3 α-naphthol 
• 121-57-3 4-aminobenzene sulfonic acid 

Downstream Products

• 85679-80-7 orange I butyrate 
• 57303-87-4 orange I acetate 
• 1453501-44-4 Na⁽¹⁺⁾*C₁₆H₁₁N₂O₄S^(1-)*C₈₀H₇₆Cl₄N₁₆O₄ 

Relevant articles and documents

Can be azo dyes obtained by grinding under solvent-free conditions?

The solid-solid reactions of some electron-donors with sulfanilic acid in the presence of solid sodium nitrite afford azo dyes by self-catalyzed diazotization of sulfanilic acid (2) under solvent-free conditions with moderate yields. Also the reactions of some electron-donors with diazotization of o-nitroaniline (5), m-nitroaniline (6) and p-nitroaniline (7) in the presence of solid sodium nitrite catalyzed by p-toluenesulfonic acid (PTSA) afford azo dyes under solvent-free conditions in good yields. This new method totally avoids the use of acids, alkalies, and toxic and/or expensive solvents in diazotization and diazo coupling reactions.