85-83-6

Basic information

• Product Name: Solvent Red 24
• Synonyms: 1-((2-Methyl-4-((2-methylphenyl)azo)phenyl)azo)-2-naphthalenol;1-((4-(o-tolylazo)-o-tolyl)azo)-2-naphtho;1-((E)-(2-Methyl-4-[(E)-(2-methylphenyl)diazenyl]phenyl)diazenyl)-2-naphth;1-(4-(o-Tolylazo)-o-tolylazo)-2-naphthol;1-(4-o-tolylazo-o-tolylazo)-2-naphthol;1-[[2-methyl-4-[(2-methylphenyl)azo]phenyl]azo]-2-naphthaleno;2',3-Dimethyl-4-(2-hydroxynaphthylazo)azobenzene;2’,3-dimethyl-4-(2-hydroxynaphthylazo)azobenzene
• CAS NO: 85-83-6
• Molecular Formula: C₂₄H₂₀N₄O
• Molecular Weight: 380.44
• EINECS: 201-635-8
• Product Categories: Organics;Solvent Dyestuff;Aromatics;Intermediates & Fine Chemicals;Pharmaceuticals;Solvents and Intermediates;Azo
• Mol File: 85-83-6.mol
• Article Data: 2

Chemical Properties

• Melting Point: 199 °C (dec.)(lit.)
• Boiling Point: 260°C
• Flash Point: 424.4 °C
• Appearance: Red Brown/Powder/Solid
• Density: 1.1946 (rough estimate)
• Vapor Pressure: 0mmHg at 25°C
• Refractive Index: 1.6000 (estimate)
• Storage Temp.: Flammables area
• Solubility: Insoluble in water; soluble in benzene, methanol, acetone, isopr
• PKA: 13.52±0.50(Predicted)
• Water Solubility: 23μg/L at 25℃
• Stability: Stable. Incompatible with strong oxidizing agents.
• Merck: 14,8393
• BRN: 709018
• CAS DataBase Reference: Solvent Red 24(CAS DataBase Reference)
• NIST Chemistry Reference: Solvent Red 24(85-83-6)
• EPA Substance Registry System: Solvent Red 24(85-83-6)

Safety Data

• Hazard Codes: Xi,T
• Statements: 36/38-45
• Safety Statements: 26-36-53-45
• WGK Germany: 3
• RTECS: QL5775000
• TSCA: Yes
• HazardClass: IRRITANT
• Hazardous Substances Data: 85-83-6(Hazardous Substances Data)

Usage

Description

Solvent Red 24 is a synthetic organic compound that belongs to the class of azo dyes. It is characterized by its bright red color and is soluble in various organic solvents, making it a versatile pigment for a range of applications.

Uses

Used in Pharmaceutical Industry:
Solvent Red 24 is used as a biological stain for promoting wound healing. Its ability to penetrate and bind to biological tissues aids in the visualization and assessment of wound healing processes.
Used in Histopathology:
In the field of histopathology, Solvent Red 24 serves as a fat stain, enabling the differentiation and identification of lipid-rich cells and tissues. This is crucial for diagnostic purposes and understanding the underlying pathology of various diseases.
Used in Environmental Testing:
Solvent Red 24 is utilized in environmental testing as a dye for detecting and analyzing dyes and metabolites in samples. This helps in monitoring and controlling the presence of pollutants and contaminants in the environment.
Used in Dye and Pigment Industry:
As a member of the azo dyes family, Solvent Red 24 is employed in the dye and pigment industry for coloring various materials, including textiles, plastics, and paints. Its solubility and color intensity make it a preferred choice for these applications.

Flammability and Explosibility

Notclassified

Safety Profile

Questionable carcinogen with experimental tumorigenic data. Mutation data reported. When heated to decomposition it emits toxic fumes of NOx.

Standard

Light Fastness

Melting point

Stable

ISO

Good

Purification Methods

Crystallise the dye from EtOH/water or acetone/water. [Beilstein 16 IV 249.]

InChI:InChI=1/C24H20N4O/c1-16-7-3-6-10-21(16)26-25-19-12-13-22(17(2)15-19)27-28-24-20-9-5-4-8-18(20)11-14-23(24)29/h3-15,29H,1-2H3/b26-25+,28-27+

Synthetic route

β-naphthol (135-19-3) + o-aminoazotoluene (97-56-3) → Sudan-IV (85-83-6)

Conditions	Yield
Stage #1: o-aminoazotoluene With hydrogenchloride In water at 20℃; for 0.5h; Stage #2: With sodium nitrate In water at 3℃; for 4h; Stage #3: β-naphthol In water for 3h; Temperature;	97.23%

β-naphthol (135-19-3) + diazotized 4'-amino-2.3'-dimethyl-azobenzene → Sudan-IV (85-83-6)

thallium (I) ethoxide (20398-06-5) + Sudan-IV (85-83-6) → Tl(1+)*C10H6ON2C6H3CH3N2C6H4CH3(1-)=TlC10H6ON2C6H3CH3N2C6H4CH3

Conditions	Yield
In tetrahydrofuran (Ar), to soln. of ligand in dry THF added dropwise soln. of TlOEt at room temp., stirred for 2 h; filtered;	99%

4-(dimethylsilyl)benzoic acid (27628-29-1) + Sudan-IV (85-83-6) → C33H30N4O2Si

Conditions	Yield
With dmap; dicyclohexyl-carbodiimide In dichloromethane at 20℃; for 24h; Inert atmosphere; Schlenk technique;	62%

Sudan-IV (85-83-6) + tin dichloride → 1-amino-2-naphthol (2834-92-6) + o-toluidine (95-53-4) + 2-methyl-p-phenylenediamine (95-70-5)

3-(Dimethylamino)propyl chloride (109-54-6) + Sudan-IV (85-83-6) → C29H31N5O (1353278-96-2)

Conditions	Yield
Stage #1: Sudan-IV With potassium hydroxide In 5,5-dimethyl-1,3-cyclohexadiene; water Reflux; Stage #2: 3-(Dimethylamino)propyl chloride In 5,5-dimethyl-1,3-cyclohexadiene; water at 70℃; for 48h; Reflux;

Upstream product

• 135-19-3 β-naphthol 
• 97-56-3 o-aminoazotoluene 

Downstream Products

• 2834-92-6 1-amino-2-naphthol 
• 95-53-4 o-toluidine 
• 95-70-5 2-methyl-p-phenylenediamine 
• 1353278-96-2 C₂₉H₃₁N₅O 

Relevant articles and documents

A CONTINUOUS PROCESS FOR THE SYNTHESIS OF AZO DYES INVOLVING IN-SITU GENERATION OF DIAZONIUM SALTS

The present disclosure provides a continuous process for the synthesis coupled compounds of diazonium salts including azo dyes involving in-situ generation of diazonium salts. It further discloses a set up to carry out the process for the synthesis of coupled compounds of diazonium salts.