| Description | 4-N,N-Dimethylaminobenzene diazonium chloride is a diazo compound found in diazo copy paper. It is allergenic only when unexposed. |
| Chemical Properties | yellow to orange crystalline powder |
| Uses | For determination of free HCl in gastric juice; spot test identification of peroxidized fats; pH indicator (red 2.9, yellow 4.0). |
| Uses | Butter yellow was largely used as a food coloring agent. It was also used for the determination of free hydrochloric acid in gastric juice, for the spot test identification of peroxidized fats, as a pH indicator, and as a laboratory reagent. |
| Uses | Formerly used as a coloring agent in foods, drugs, and cosmetics |
| Preparation | aniline diazotization, and N,N-dimethylaniline coupling. |
| Definition | A banned food coloring. |
| Production Methods | 4-Dimethylaminoazobenzene was produced in large quantities in the early 1900s but is currently not produced in any significant commercial quantity in the United States. |
| General Description | Yellow crystalline leaflets or an orange powder. |
| Air & Water Reactions | Dust may form an explosive mixture in air. Insoluble in water. |
| Reactivity Profile | Solvent Yellow 2 can detonate, particularly if sensitized by the presence of metal salts or strong acids. May form toxic gases with acids, aldehydes, amides, carbamates, cyanides, inorganic fluorides, halogenated organics, isocyanates, ketones, metals, nitrides, peroxides, phenols, epoxides, acyl halides, and strong oxidizing or reducing agents. May form flammable gases with alkali metals. May react explosively with strong oxidizing agents, metal salts, peroxides, and sulfides. May react explosively with strong oxidizing agents, metal salts, peroxides, and sulfides. |
| Hazard | Carcinogen. |
| Health Hazard | 4-Dimethylamino-azobenzene (XIII) is the parent compound of the amino-azo dye carcinogens; it is also known in the earlier literature as Butter Yellow, because it was used to color butter and vegetable oils before its carcinogenic activity was discovered. Many derivatives of XIII have been prepared and tested for carcinogenic activity. In the rat, the amino-azo dye carcinogens, administered in the diet, specifically induce hepatomas. Tumor induction by most of the amino-azo dyes is delayed or inhibited by high dietary levels of riboflavin (vitamin B2) or protein. Replacement of the –N=N– azo linkage by –CH=CH–, as in 4-dimethylaminostilbene (XIV), results in widening the target tissue spectrum; XIV induces tumors in the liver, mammary gland, and ear duct. Mice are much more resistant than rats to the carcinogenic activity of both amino-azo dyes and aminostilbenes. |
| Fire Hazard | Flash point data for Solvent Yellow 2 are not available. Solvent Yellow 2 is probably combustible. |
| Safety Profile | Confirmed carcinogen with experimental carcinogenic, neoplastigenic, and tumorigenic data. Poison by ingestion and intraperitoneal routes. Experimental teratogenic and reproductive effects. Human mutation data reported. When heated to decomposition it emits toxic fumes of NOx |
| Carcinogenicity | 4-Dimethylaminoazobenzene is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity fromstudies in experimental animals. |
| Environmental fate | Chemical/Physical. Releases toxic nitrogen oxides when heated to decomposition (Sax and Lewis, 1987).
At influent concentrations of 1.0, 0.1, 0.01, and 0.001 mg/L, the GAC adsorption capacities were 249, 140, 83, and 48 mg/g, respectively (Dobbs and Cohen, 1980). |
| Purification Methods | Crystallise the dye from acetic acid or isooctane, or from 95% EtOH by adding hot water and cooling. Dry it over KOH under vacuum at 50o. [Beilstein 6 IV 448.] CARCINOGEN. |
| Properties and Applications | yellow to red light yellow. Light yellow powder, melting point 115 ℃ (yellow flaky crystal). Insoluble in water, soluble in ethanol for yellow solution, in oil soluble. In concentrated sulfuric acid to yellow, red after diluted solution; . Mainly used for Aviation fuel TETRAETHYLLEAD stability agent and pH indicator, also used in paraffin, polystyrene, oil and soap stain
StandardLight FastnessHeat-resistant(℃)WaterSodium Carbonate(5%)Hydrochloric acid(5%)Melting pointStableISOGeneral113.5-115120PoorWellPoor |
| Toxicity evaluation | Butter yellow exists as a stable crystalline material at normal temperature and pressure. It is insoluble in water, but soluble in organic solvents such as alcohol, chloroform, ether, petroleum ether, mineral acids, oils, and pyridine. Its octanol/water partition coefficient is 4.58, vapor pressure is 3.3×10-7 mm Hg; and Henry’s law constant is 7.1×10-9 atm-m3 mol-1.
Butter yellow may be released into the environment as a result of its manufacture and use in the consumer products. It may bind to the soil and when released into water, may bioconcentrate in aquatic organisms, or may be adsorbed into the sediment. If released in the atmosphere, it may undergo direct photolysis. |
