Methyl yellow
| Names | |
|---|---|
| IUPAC name
N,N-Dimethyl-4-(phenyldiazenyl)aniline
| |
| Other names
4-Dimethylaminoazobenzene
Butter Yellow C.I. 11020 DAB N,N-Dimethyl-4-aminoazobenzene N,N-Dimethyl-4-phenylazoaniline p-Dimethylaminoazobenzene Solvent Yellow 2 | |
| Properties | |
| C14H15N3 C6H5N2C6H4N(CH3)2 | |
| Molar mass | 225.295 g/mol |
| Appearance | Yellow solid |
| Odor | Odorless |
| Density | 1.2233 g/cm3[1] |
| Melting point | 110–112 °C (230–234 °F; 383–385 K) [3] |
| Boiling point | Decomposes |
| 0.00136 g/100 ml | |
| Solubility | Soluble in ethanol, pyridine |
| Solubility in pyridine | 28 g/100 g (22.5 °C)[2] |
| Vapor pressure | ~0 mmHg |
| Thermochemistry | |
| Hazards | |
| Safety data sheet | Fisher Scientific |
| Lethal dose or concentration (LD, LC): | |
| LD50 (Median dose)
|
200 mg/kg (rat, oral) |
| Related compounds | |
| Related compounds
|
Methyl orange Methyl red |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Methyl yellow, or C.I. 11020, is an organic chemical compound, an azo dye, sometimes used as pH indicator.
Contents
[hide]Properties
Chemical
In aqueous solution at low pH, methyl yellow appears red. Between pH 2.9 and 4.0, methyl yellow undergoes a transition, to become yellow above pH 4.0.
Physical
Methyl yellow is a yellowish solid, almost insoluble in water, but more soluble in alcohols.
Availability
Methyl yellow is sold by chemical suppliers.
Preparation
Methyl yellow can be synthesized from the diazotization reaction of aniline with N,N-dimethylaniline, using sodium nitrite with hydrochloric acid, at low temperatures.[6][7][8] Yield of this process varies between 84 to 97%, depending on the method.
Projects
- pH indicator
Handling
Safety
Methyl yellow displays moderate toxicity. It is classified as a possible carcinogen.
Storage
In closed bottles.
Disposal
Can be destroyed using strong oxidizing solutions suited for neutralizing aromatics, like Fenton's reagent or piranha solution, or using a strong oxidizing solution and strong UV light, from a UV lamp.
References
- Jump up ↑ Whitaker, A.; Journal of Crystallographic and Spectroscopic Research; vol. 22; nb. 2; (1992); p. 151 - 155
- Jump up ↑ Dehn; Journal of the American Chemical Society; vol. 39; (1917); p. 1400
- Jump up ↑ Valizadeh, Hassan; Shomali, Ashkan; Nourshargh, Saideh; Mohammad-Rezaei, Rahim; Dyes and Pigments; vol. 113; (2015); p. 522 - 528
- Jump up ↑ Lemoult; Comptes Rendus Hebdomadaires des Seances de l'Academie des Sciences; vol. 143; (1906); p. 604
- Jump up ↑ Annales de Chimie (Cachan, France); vol. <8>14; (1908); p. 300
- Jump up ↑ Valizadeh, Hassan; Shomali, Ashkan; Dyes and Pigments; vol. 92; nb. 3; (2012); p. 1138 - 1143
- Jump up ↑ Bahulayan, Damodaran; John, Litka; Lalithambika, Malathy; Synthetic Communications; vol. 33; nb. 6; (2003); p. 863 - 869
- Jump up ↑ Gomez-Vallejo, Vanessa; Borrell, Jose I.; Llop, Jordi; European Journal of Medicinal Chemistry; vol. 45; nb. 11; (2010); p. 5318 - 5323
