Of dimethylaniline

Dissolve 2 g. of anhydrous sodium carbonate in 50 ml. of water contained in a 400 ml. beaker and add 7 g. of finely powdered crystalline sulphanilic acid (2H2O), warming the mixture gently in order to obtain a clear solution. Add a solution of 2 2 g. of sodium nitrite in 10 ml. of water and then cool the mixture in ice-water until the temperature has fallen to 5°. Now add very slowly (drop by drop) with continual stirring a solution of 8 ml. of concentrated hydrochloric acid in 15 ml. of water do not allow the temperature to rise above 10°. When all the acid has been added, allow the solution to stand in ice-water for 15 minutes to ensure complete diazotisation during this period fine crystals of the internal salt separate from the pink solution. Dissolve 4 ml. of dimethylaniline in a mixture of 4 ml. of concentrated hydrochloric acid and 10 ml. of water, cool the solution in ice-water, and add it slowly to the cold well-stirred diazo solution a pale red coloration is developed. Allow the mixture to stand for 5 minutes and then add slowly with stirring aqueous... 

The following preparation of triethyl phosphite illustrates the interaction of phosphorus trichloride and ethanol in the presence of dimethylaniline the preparation of di-isopropyl hydrogen phosphite illustrates that of phosphorus trichloride and isopropanol in the absence of a tertiary amine. 

Formation of methyl-orange cf. p. 214). Dissolve about 0 3 g. of sul-phanilic acid in 2 ml. of 10% aqueous NajCOj solution. Cool m ice-water and add 2 to 3 drops of 20% NaNOj solution. Now add about I ml. of cold dil. HCl, shake and leave for 2-3 minutes. Meanwhile dissolve i drop of dimethylaniline in a few drops of dil. HCl, cool thoroughly in ice-water and then add to the cold diazo solution. Shake well and make alkaline with aqueous NaOH solution note the formation of a deep orange-yellow coloration or precipitate. On the addition of HCl, a bright red coloration is produced. 

Pure dimethylaniline from commercial dimethylaniline. Into a 250 ml. round-bottomed flask fitted with a reflux condenser place 50 g. (52-5 ml.) of a good commercial sample of dimethylaniline and 25 g. (23 ml.) of acetic anhydride. Heat vmder reflux for 3 hours, and allow to cool. Transfer to a 100 ml, Claisen flask equipped for distillation, and distil using a wire gauze or, better, an air bath (Fig. II, 5, 3). Some acetic acid and the excess of acetic anhydride passes over first, followed by pure dimethylaniline (a colourless liquid) at 193-194°, There is a small dark residue in the flask. The yield depends upon the purity of the commercial sample, but is usually 30-40 g. 

Dissolve 10 g. of dimethylaniline in 10 ml. of dilute hydrochloric acid (1 1), cool to 0-5°, and slowly add, with stirring, a solution of 0 -70 g. of sodium nitrite in 4 ml. of water. After 20-30 minutes, filter off the precipitated yellow hydrochloride, and wash it with a little dilute hydrochloric acid. Dissolve the precipitate in the minimum volume... 

This compound, also termed tetramethyl base is prepared by the condensation of dimethylaniline (2 mols) with formaldehyde (1-2 mols) in the presence of a little sulphanilic add ... 

In a 500 ml. three-necked flask, fitted with a reflux condenser and mechanical stirrer, place 121 g. (126-5 ml.) of dimethylaniline, 45 g. of 40 per cent, formaldehyde solution and 0 -5 g. of sulphanilic acid. Heat the mixture under reflux with vigorous stirring for 8 hours. No visible change in the reaction mixture occurs. After 8 hours, remove a test portion of the pale yellow emulsion with a pipette or dropper and allow it to cool. The oil should solidify completely and upon boiling it should not smell appreciably of dimethylaniline if this is not the case, heat for a longer period. When the reaction is complete, steam distil (Fig. II, 41, i) the mixture until no more formaldehyde and dimethylaniline passes over only a few drops of dimethylaniline should distil. As soon as the distillate is free from dimethylaniline, pour the residue into excess of cold water when the base immediately solidifies. Decant the water and wash the crystalline solid thoroughly with water to remove the residual formaldehyde. Finally melt the solid under water and allow it to solidify. A hard yellowish-white crystalline cake of crude base, m,p. 80-90°, is obtained in almost quantitative yield. RecrystaUise from 250 ml. of alcohol the recovery of pure pp -tetramethyldiaminodiphenylmethane, m.p. 89-90°, is about 90 per cent. 

Some reference to the use of nitrous acid merits mention here. Primary aromatic amines yield diazonium compounds, which may be coupled with phenols to yield highly-coloured azo dyes (see Section IV,100,(iii)). Secondary aromatic amines afford nitroso compounds, which give Liebermann a nitroso reaction Section IV,100,(v). Tertiary aromatic amines, of the type of dimethylaniline, yield p-nitroso derivatives see Section IV,100,(vii). ... 

Acetyl chloride [75-36-5] M 78.5, b 52 , d 1.1051, n 1.38976. Refluxed with PCI5 for several hours to remove traces of acetic acid, then distd. Redistd from one-tenth volume of dimethylaniline or quinoline to remove free HCl. A.R. quality is freed from HCl by pumping it for Ih at -78 and distg into a trap at -196 . 

The sulphanilic acid is dissolved in the sodium carbonate (i mol.) solution and the sodium nitrite (i mol.) solution added. The mixture is cooled in ice, and the solution of hydrochloi ic acid (i mol.) gradually added. The solution of dimethylaniline (i mol.) is now poured in, and the liquid made alkaline with caustic soda. The separation of methyl orange at once begins, and is assisted by the addition of a little common salt (20 grams). The precipitate is filtered at the pump, and crystallised from hot water. Yield, nearly theoretical. 

Trichloro-s-triazine also reacts readily with carbon or phosphorus nucleophiles. Diethylmalonate anion forms a mono-derivative under mild conditions and the tri-substitution product (327) under vigorous conditions with excess nucleophile. Nucleophilic attack by the 7r-electrons of ketene diethylacetal to give 254 and of dimethylaniline to give 253 has been mentioned earlier. Two... 

A cooled 10% solution of 1 mol of phosgene in toluene was added with stirring to a cooled solution of 1 mol of 2-methyl-2-propyl-1,3-propanediol and 2 mols of dimethylaniline also dissolved in toluene, at such a rate that the temperature of the mixture was maintained at about 25°C. The mixture was allowed to remain at this temperature for several hours, then... 

A mixture of 4.9 grams of 5,6-dihydro-6-oxo-morphanthridine, 37 ml of phosphorus oxychloride and 1.5 ml of dimethylaniline Is heated for 3 hours at reflux. The viscous oil, obtained by evaporation of the reaction mixture in vacuo at 60°C, Is diluted with 20 ml of absolute dioxane and, after adding 30 ml of N-methylpiperazine, heated for 4 hours at reflux. The resulting clear solution Is evaporated in vacuo at 60°C to dryness. The residue is distributed between ether and ammonia water. The ethereal solution is separated, washed with water and then extracted with 1 N acetic acid. The acetic acid extract is mixed with ammonia water and then extracted with ether. The ethereal solution is washed with water, dried over sodium sulfate, filtered through alumina and evaporated. 

Tetryl. In the manufacture of Tetryl, it is usual not to nitrate dime thy laniline directly, but to dissolve it first in coned sulfuric acid and then to nitrate the dimethylaniline sulfate so obtained. Direct nitration of dimethylaniline proceeds so violently that it can be carried out only under specialized conditions. Many years experience of Tetryl manufacture has shown that the ratio of sulfuric acid to dimethylaniline should not be lower than 3 1, since a smaller amount of sulfuric acid may be detrimental to the nitration process. However, the ratio of sulfuric acid to dimethylaniline must not be too high, otherwise Tetryl yield is decreased. Temp must be maintained between 20-45° to avoid sulfonation of the benzene ring. Care must be exercised not to leave any unreacted dimethylaniline prior to introduction of nitric acid, because of the potential violence of the dimethyl-aniline-nitric acid reaction. Consequently, continuous methods of prepn are to be preferred as they inherently minimize accumulation of unreacted dimethylaniline... 

Reaction of N,N-dimethylaniline with 1-cyanobenziodoxol 1783 to afford N-methyl-N-cyanomethylaniline 1784 in 97% yield has been discussed in Section 12.1 [31]. Analogously, oxidation of dimethylaniline with iodosobenzene and trimethylsilyl azide 19 at 0°C in CDCI3 gives the azido compound 2040 in 95% yield, iodobenzene, and HMDSO 7 [194, 195] (Scheme 12.56). Likewise, the nucleophilic catalyst 4-dimethylaminopyridine (DMAP) is oxidized, in 95% yield, to the azide 2041, which is too sensitive toward hydrolysis to 4-N-methylaminopyri-dine to enable isolation [194, 195]. Amides such as 2042, in combination with tri-... 

Dimethylaminobenzaldehyde has been prepared previously from dimethylaniline, formaldehyde, and />-nitrosodimethylani-line in 56-59% yield,3 by the formylation of dimethylaniline with A-methylformanilide in approximately 50% yield,4 and by the formylation of dimethylaniline with dime thylformamide.6... 

It was discovered by Michler and Meyer in 1879 and was made by the nitration of dimethylaniline. One methyl group is oxidised and at the same time the benzene nucleus is nitrated in the 2, 4, 6-positions. The usual method of preparation from dimethylaniline is to dissolve 1 part of dimethylaniline in 14 to 15 parts of sulphuric acid to this solution about 9 parts are added of a mixed acid containing 67% of nitric acid and 16% of... 

At 20-30°C, decomposition occurred in 10-30 min. Addition of 1% of aniline, 1,2-diaminoethane or potassium iodide caused instant decomposition, and of dimethylaniline, instant explosion. 

The solid peroxide exploded on contact with a drop of dimethylaniline. 

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