Methyl red

• CAS: 493-52-7
• Catalog Number: ACM493527
• Category: Other Products
• Molecular Weight: 269.30
• Molecular Formula: C15H15N3O2
• Description: Methyl red (2-(N,N-dimethyl-4-aminophenyl) azobenzenecarboxylic acid), also called C.I. Acid Red 2, is an indicator dye that turns red in acidic solutions. It is an azo dye, and is a dark red crystalline powder. Methyl red is a pH indicator; it is red in pH under 4.4, yellow in pH over 6.2, and orange in between, with a pKa of 5.1. Murexide and methyl red are investigated as promising enhancers of sonochemical destruction of chlorinated hydrocarbon pollutants. Methyl red is classed by the IARC in group 3 – unclassified as to carcinogenic potential in humans.
• Synonyms: 2-[4-(dimethylamino)phenylazo]benzoic acid;4′-dimethylaminoazobenzene-2-carboxylic acid;Methyl Red,indicator;2-(4-Dimethylaminophenylazo)benzoic acid;4-Dimethylaminoazobenzene-2′-carboxylic acid
• IUPAC Name: 2-[4-(dimethylamino)phenyl]diazenylbenzoic acid
• SMILES: CN(C)C1=CC=C(C=C1)N=NC2=CC=CC=C2C(=O)O
• InChI Key: CEQFOVLGLXCDCX-UHFFFAOYSA-N
• Boiling Point: 479.5ºC at 760mmHg
• Melting Point: 178-182ºC
• Flash Point: 11ºC
• Density: 0.839 g/mL at 25ºC
• Appearance: Red crystalline powder
• EC Number: 207-776-1
• Exact Mass: 269.11600
• Hazard Codes: Xn
• Hazard Statements: Xn:Harmful
• H-Bond Acceptor: 5
• H-Bond Donor: 1
• HS Code: 29270000
• LogP: 3.86620
• MDL Number: MFCD00002425
• PSA: 65.26
• Refractive Index: 1.592
• RIDADR: UN 1170
• Safety Description: S36/37
• Stability: Stable. Incompatible with strong oxidizing agents.
• Storage Conditions: -20ºC
• Vapor Pressure: 2.89E-10mmHg at 25°C

Synthetic Use

Upstream Synthesis Route 1

• 118-92-3

• 493-52-7

Reference: [1]Rupp; Loose
[Chemische Berichte, 1908, vol. 41, p. 3906]

Upstream Synthesis Route 2

• 17333-86-7
• 121-69-7

• 493-52-7

Reference: [1]Rupp
[Archiv der Pharmazie, 1915, vol. 253, p. 372]
Tizard
[Journal of the Chemical Society, 1910, vol. 97, p. 2487]
Schorger
[Industrial and Engineering Chemistry, 1923, vol. 15, p. 742][Chemisches Zentralblatt, 1923, vol. 94, # IV, p. 933]
Current Patent Assignee: MERCK KGAA - DE409282, 1925, C
[Fortschr. Teerfarbenfabr. Verw. Industriezweige, vol. 14, p. 955][Fortschr. Teerfarbenfabr. Verw. Industriezweige, vol. 14, p. 955]

Downstream Synthesis Route 1

• 51-85-4
• 493-52-7

• 139895-90-2

Reference: [1]Mullen, Ken I.; Wang, DaoXin; Crane, L. Gayle; Carron, Keith T.
[Analytical Chemistry, 1992, vol. 64, # 8, p. 930 - 936]

* For details of the synthesis route, please refer to the original source to ensure accuracy.