4- Dimethylaminoazobenzene

Formerly used as a coloring agent in foods, drugs, and cosmetics 

In humans, contact dermatitis was observed in 90% of factory workers handling DAB. There have been no reports of an increased cancer incidence among exposed persons.  

Two of 10 dogs survived ingestion of 20mg/kg/day for 38 months of continuous treatment followed by 48 months of intermittent treatment both developed bladder papillomas. Oral administration of 1, 3, 10, 20, or 30mg/day produced liver tumors in rats the induction time was inversely proportional to the daily dose, ranging between 34 days for the 30mg/day dose and 700 days for the 1 mg/day dose. In rats fed 5 mg DAB/day for 40-200 days and then kept for their life span on a normal diet, there was a 20-81% incidence of liver carcinoma.  

Cutaneous application of 1ml of a 2% solution of DAB in acetone two times/week for 90 weeks caused skin tumors in all six male rats treated. Squamous cell, basal cell, and anaplastic carcinomas were observed there were no tumors in controls given acetone alone.  

DAB was genotoxic in the comet assay inducing DNA damage in the stomach, colon liver, bladder, lung, and bone marrow. It is also mutagenic to Salmonella in the Ames test. Because of its demonstrated carcinogenicity in animals, human exposure to DAB by any route should be avoided. In recent years, this compound has been used only in laboratories as a model of tumorigenic activity in animals. It is not produced commercially in the United States and is of little occupational health importance. 

N-Dimethyl-4-(phenylazo)benzenimine, butter yellow, methyl yellow, solvent yellow 2, Cl 11020. 

Yellow crystals leaflets from ethanol mp, 114-117°C.1 Decomposes on exposure to heat or light.2 

Insoluble in water soluble in alcohol, benzene chloroform, ether, petroleum ether, 

Animal carcinogen.2-5 Factory workers may develop contact dermatitis.4 The characteristic acute toxic effect is methemyglobinemia. LD50 (oral, rat) 200 mg/kg4 LD50 (i.p., mouse) 500 mg/kg LD50 (oral, mouse) 300 mg/kg.5 Reasonably anticipated to be a human carcinogen.2 

Wear dust mask, goggles, rubber gloves, and protective clothing. Carefully scoop the solid into a beaker and transport to the fume hood. Dispose of the material using the waste disposal procedure. Wash the spill site with soap and water disposing of cleaning materials in a sealed bag or container for burning.6 7 

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C,H5N,NHC,Hs+HC1 = C,H 5N C1+H,NC,H5- C H5N NC H NH +HC1 gen atom of the aniline molecule, giving aminoazobenzene. Since this reaction is irreversible, whilst the former is freely reversible, the final result is the complete conversion of the diazoaminobenzene into the aminoazobenzene. (The intermediate formation of the benzenediazonium chloride can be demonstrated by adding dimethylaniline, with which the diazonium chloride couples preferentially, giving dimethylaminoazobenzene, C6HsN NC6HiN(CH3)i.)... 

Methyl yellow, p-dimethylaminoazobenzene, benzeneazodimethylaniline (indicator) dissolve 0.1 g in 200 mL alcohol pH range red 2.9-4.0 yellow. The color change from yellow to orange can be perceived somewhat more sharply than the change of methyl orange from orange to rose, so that methyl yellow seems to deserve preference in many cases. See also under methyl orange. 

Methyl Red (4-dimethylaminoazobenzene-2 -carboxylic acid) [493-52-7] M 269.3, m 181-182 , Cl 13020, pK j 2.30, pK2 4.82. The acid is extracted with boiling toluene using a Soxhlel apparatus. The crystals which separated on slow cooling to room temperature are filtered off, washed with a little toluene and recrysld from glacial acetic acid, benzene or toluene followed by pyridine/waler. Alternatively, dissolved in aq 5% NaHC03 soln, and ppted from hot soln by dropwise addition of aq HCl. Repealed until the extinction coefficients did not increase. 

Sodium /7-dimethylaminoazobenzene-<9 -carboxylate [845-10-3] M 219.2. Ppted from aqueous soln as the free acid which was recrystallised from 95% EtOH, then reconverted to the sodium salt. 

Diethyl aniline, 54 Diethylcarbaniazine citrate, 54 Diethyl carbamyl chloride, 54 Diethyl chlorophosphate, 54 Diethylene triamine, 54 Diethyl ether, 54 Di(2-ethylhexyl) phthalate, 54 Diethyl ketone, 54 Diethyl-p-phenylenediamine, 54 Diethyl phthalate, 54 Diethylstilbestrol, 55 Diethyl sulfate, 55 Diethyl zinc, 55 Difluoromethane chloride, 55 Digitoxin, 55 Diglycidyl ether, 55 Digoxin, 55 Diisobutyl ketone, 55 Diisopropylamine, 55 Diisopropyl ether, 55 DIKAMIN , 2,4-D, 55 DIKONIRT , 2,4-D, 55 Dimefox, 55 Dimethoate, 55 3,3 -Dimethoxybenzidine, 55 n,n-Dimethylacetamide, 56 Dimethylamine, 56 4-Dimethylaminoazobenzene, 56 Dimethylaminoethanol, 56 n,n-Dimethyl aniline, 56 7,12-Dimethylbenz[a]anthracene, 56 3,3 -Dimethylbenzidine, 56... 

Suitably substituted azo compounds constitute an important class of dyes—the azo dyes. Some derivatives such as /j-dimethylaminoazobenzene- p -sulfonic acid Na-salt (trivial name methyl orange) are used as pH-indicators. 

Two other types of host for arenediazonium salts were found by Shinkai et al., the calix[ ]arenes, 11.10 (1987 a, 1987 b) and 11.11 (1988). The hexasulfonated calix[6]arenes 11.10 suppress dediazoniation of substituted benzenediazonium ions in aqueous solution much more efficiently than 18-crown-6. The complexation of calix[ ]arenes 11.11 (n = 4, 6, and 8) with 4 -dimethylaminoazobenzene-4-diazonium ions (11.12) was measured, and was found to be weaker than that of 18-crown-6. It may be that the large difference in behavior between these two types of complexation reagents 11.10 and 11.11 is due to the significantly different diazonium ions used as guests for the two types. Electronically the azobenzenediazonium ion (11.12) is... 

Similar processes occur with azo compounds [10]. trans-Dimethylaminoazobenzene (butter yellow) yields some of the cis isomer on irradiation with long-wavelength UV light and this possesses a lower hRf than the trans compound on rechromatographing with the same mobile phase using the two-dimensional SRS technique (Fig. 17). IR and MS measurements were used to confirm that no oxygen had been incorporated into the molecule. 

Dimethyl-4-heptanone (diisobutyl ketone) Dimethyl sulphate N,N-Dimethyl-p-toluidine Dimethylamine 4-Dimethylaminoazobenzene... 

Dimethylaminoazobenzene Ethyl diazoacetate Ethylenethiourea Ethyl iV-nitroso carbamate ... 

Mueller, G.C. and Miller, J.A. The reductive cleavage of l+-dimethylaminoazobenzene by rat liver the intracellular distribution of the enzyme system and its requirement for triphosphopyridine nucleotide. J. Biol. Chem. (191+9) 180, 1125-1136. 

Fig. 14 Reduction of PhjCSPh by electrochemically generated aromatic anion radicals (in DMF at 25°C). Variation of the rate-determining step rate constant, A , with the standard potential of the aromatic anion radical, p,g (from left to right azobenzene, benzo[c]cinnoline, 4-dimethylaminoazobenzene, terephthalonitrile, naphthacene, phlhalonitrile, perylene, fluoranthene, 9,10-diphenylanthracene). The dotted lines are the theoretical limiting behaviours corresponding to the concerted (right) and stepwise (left) pathways. (Adapted from Severin et al 1988.)...

Generation of acidity in silica gel by ionizing radiation was reported by Barter and Wagner (274). p-Dimethylaminoazobenzene was adsorbed out of anhydrous solution in CCI4 in the red, acid form. About 3 /aeq/gm of acid sites were generated by a dose of 3 10 rad, as determined by titration with butylamine. 

Dimethylaminoazobenzene is adsorbed by TiOg as red salt only after ultraviolet irradiation. 

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