25956-17-6

Basic information

• Product Name: ALLURA RED AC
• Synonyms: 2-naphthalenesulfonicacid,6-hydroxy-5-[(2-methoxy-5-methyl-4-sulfophenyl)azo];2-Naphthalenesulfonicacid,6-hydroxy-5-[(2-methoxy-5-methyl-4-sulfophenyl)azo]-,disodiumsalt;6-hydroxy-5-((6-methoxy-4-sulfo-m-tolyl)azo)-2-naphthalenesulfonicacidiso;alluraredacdye;c.i.foodred17;fd&credno.40;foodred17;redno.40
• CAS NO: 25956-17-6
• Molecular Formula: C₁₈H₁₄N₂O₈S₂*2Na
• Molecular Weight: 496.42
• EINECS: 247-368-0
• Product Categories: Dyes and Pigments;Analytical Chemistry;Food Colors by Food Sanitation Law in Japan;A;Stains and Dyes;Stains&Dyes, A to;Aromatics;Intermediates & Fine Chemicals;Pharmaceuticals;Sulfur & Selenium Compounds;Azo
• Mol File: 25956-17-6.mol
• Article Data: 0

Chemical Properties

• Melting Point: >300 °C(lit.)
• Boiling Point: 325.16℃[at 101 325 Pa]
• Appearance: Dark red/powder
• Density: 0.448[at 20℃]
• Vapor Pressure: 0Pa at 25℃
• Storage Temp.: Inert atmosphere,Room Temperature
• Solubility: Soluble in water, ethanol
• Water Solubility: 53.878g/L at 25℃
• Stability: Very Hygroscopic, Light Sensitive
• Merck: 14,284
• CAS DataBase Reference: ALLURA RED AC(CAS DataBase Reference)
• NIST Chemistry Reference: ALLURA RED AC(25956-17-6)
• EPA Substance Registry System: ALLURA RED AC(25956-17-6)

Safety Data

• Safety Statements: 22-24/25
• WGK Germany: 2
• RTECS: QK2260000
• Hazardous Substances Data: 25956-17-6(Hazardous Substances Data)

Usage

Description

ALLURA RED AC, also known as FD&C Red No. 40, is a synthetic red azo dye primarily used as a color additive in the food, drug, and cosmetic industries. It is a red powder that dissolves in water to give a red solution at neutrality and in acid, and a dark red solution in base. ALLURA RED AC has good stability to pH changes, light, heat, and shows no appreciable change in 10% sugar systems. However, it has fair to poor stability to oxidation.

Uses

Used in Food Industry:
ALLURA RED AC is used as a color additive for enhancing the appearance of various food products such as beverages, desserts, candy, confections, cereals, and ice cream. It provides a yellowish-red hue and has very good tinctorial strength, making it a popular choice for the industry.
Used in Pharmaceutical Industry:
ALLURA RED AC is used as a colorant in the pharmaceutical industry for coloring drugs. Its good stability to pH changes, light, and heat makes it suitable for this application.
Used in Cosmetics Industry:
ALLURA RED AC is also used as a color additive in the cosmetics industry, where it helps improve the visual appeal of various cosmetic products.
However,

Preparation

4-Amino-5-methoxy-2-methylbenzenesulfonic acid diazo, and 6-Hydroxynaphthalene-2-sulfonic acid?coupling.

Flammability and Explosibility

Nonflammable

InChI:InChI=1/C18H16N2O8S2.2Na/c1-10-7-14(16(28-2)9-17(10)30(25,26)27)19-20-18-13-5-4-12(29(22,23)24)8-11(13)3-6-15(18)21;;/h3-9,21H,1-2H3,(H,22,23,24)(H,25,26,27);;/q;2*+1/p-2/b20-19+;;

Synthetic route

Allura Red AC (25956-17-6) → allura red sulfonyl chloride

Conditions	Yield
With thionyl chloride In 1,2-dichloro-ethane; N,N-dimethyl-formamide at 20 - 60℃; for 4.5h;	81.3%

ethyl violet (2390-59-2) + Allura Red AC (25956-17-6) → C18H13N2O8S2(3-)*3C31H42N3(1+)

Conditions	Yield
In water pH=10;

Allura Red AC (25956-17-6) + sodium thiomethoxide (5188-07-8) → 2Na(1+)*C19H16N2O7S3(2-)

Conditions	Yield
Stage #1: Allura Red AC With trifluoromethylsulfonic anhydride Stage #2: sodium thiomethoxide With tetrakis(triphenylphosphine) palladium(0)

aluminum(III) nitrate nonahydrate + zinc(II) nitrate hexahydrate + sodium hydroxide (1310-73-2) + Allura Red AC (25956-17-6) → 0.49C18H14N2O8S2(2-)*3.5H2O*Zn3.84Al1.19(OH)8(0.98+)

Conditions	Yield
at 70℃; for 72h; pH=9.5; Inert atmosphere;

aluminum(III) nitrate nonahydrate + sodium hydroxide (1310-73-2) + Allura Red AC (25956-17-6) → 0.48C18H14N2O8S2(2-)*3.6H2O*Mg2.62Al0.88(OH)8(0.96+)

Conditions	Yield
With magnesium(II) nitrate hexahydrate at 70℃; for 72h; pH=9.5; Inert atmosphere;

Downstream Products

• 119-79-9 5-aminonaphthalene-2-sulfonic acid