2.4- Dimethylaniline hydrochloride

A mixture of 55.1 g 2,4-dimethylaniline hydrochloride, 83.7 g p-toluenesulphonyl chloride and 150 ml N-methylformamide was stirred with occasional cooling to maintain the temperature at 20°-35°C. When the exothermic reaction had subsided, the mixture was stirred at room temperature for 4 h, poured into a mixture of ice and water, and basified with 10 N sodium hydroxide solution, keeping the temperature of the mixture... 

In a 2-1. flask equipped with a reflux condenser, mercury-sealed stirrer, and a dropping funnel are placed 147 ml. (114 g., 1.5 moles) of ferf.-butyl alcohol (Note 1), 212 ml. (202 g., 1.67 moles) of dimethylaniline, and 200 ml. of dry ether. The solution is heated to refluxing, and 113 ml. (124 g., 1.58 moles) of acetyl chloride is run into the stirred solution at such a rate that moderate refluxing continues after the source of heat is removed. When approximately two-thirds of the acetyl chloride has been added, dimethylaniline hydrochloride begins to crystallize and the mixture refluxes very vigorously. An ice bath is applied immediately, and, after refluxing ceases, the remainder of the acetyl chloride is added. Finally, the mixture is heated for 1 hour on a water bath. The mixture is cooled to room tempera-... 

The salts of p-nitrosodimethylaniline, on the other hand, are yellow. Moreover, since they are neutral-—test this with the pure salt—and since dimethylaniline hydrochloride is add to litmus paper, they cannot have resulted from the simple addition of the acid to the tertiary dimethylamino-group. It is therefore assumed that the salts are formed by the addition of H and acid ion in the 1 7-positions, so that a quinonoid system results through a rearrangement ... 

In a 3-I. round-bottom flask fitted with a mechanical stirrer 150 g. of technical dimethylaniline are dissolved in 750 cc. of diluted hydrochloric acid (1 part concentrated acid to 1 part water). This solution is now cooled to o° and a solution (previously cooled to o°) of 90 g. of technical sodium nitrite in 150 cc. of water is added through a separatory funnel. During the addition of the nitrite solution, mechanical stirring should be employed and the flask cooled well with ice and salt. The addition is made at such a rate (thirty to forty minutes for the entire addition) that the temperature does not rise above 50. The precipitate of nitroso dimethylaniline hydrochloride is filtered off with suction, then washed with about 300 cc. of diluted hydrochloric acid (1 1). 

Cyclohexylurea has been prepared by the reaction of cyclo-hexyl isocyanate with gaseous ammonia or ammonium hydroxide, by thermal decomposition of cyclohexyl allophanamide, by treating cyclohexylamine hydrochloride with an aqueous solution of potassium cyanate," by heating nitrosomethylurea with cyclohexylamine, and by heating an ethanolic solution of cyclohexylamine and 3,5-dimethyl-l-carbamylpyrazole. 2,6-DimethyIphenyIthiourea has been synthesized by allowing 2,6-dimethylaniline hydrochloride to react with ammonium thiocyanate. ... 

Polynucleotides. These compounds are now generally prepared by use of a bifunctional phosphitylating agent such as o-chlorophenylphosphorodichloridite (6, 114-115) or methoxydichlorophosphine, CHjOPCl,. The intermediate nucleoside phosphites from these reagents tend to be unstable. This difficulty can be alleviated by use of I, which reacts with suitably protected nucleosides to form stable phosphoramidales 2 in good yield. These products can be activated for formation of a dinucleotide phosphite (4) by treatment with a weak acid such as N,N-dimethylaniline hydrochloride or l/Z-tetrazole (5). 

It was later found that dialkyl(dialkylamino) phosphites (phosphoramidites, (RO)2PNR2 [114]), which are stable towards air and water and can be stored for longer, can readily be converted into the phosphinic chlorides (RO)2PCl by treatment with dimethylaniline hydrochloride, or into the corresponding tetrazolides by treatment with tetrazole. Tetrazolides (RO)2P-(l-tetrazolyl) had proven excellent reagents for the phosphorylation of nucleosides [113], and the treatment of phosphoramidites with alcohols in the presence of tetrazole was found to be a satisfactory method for the rapid preparation of trialkyl phosphites [115,116]. 

Tellurium tetrachloride and dimethylaniline interact in dry ether solution to give foVdimethvlaniline tellurium tetrachloride, a purely additive compound, and a small amount of substitution product, 4 4 -tetramethyldiaminodiphenyl telluridichloride. The latter is more conveniently obtained by digesting the tetrachloride in boiling water, and the mother-liquors from this conversion yield on addition of hydrogen chloride fm-dimethylaniline hydrochloride tellurium tetrachloride. Reduction of the dichloride by alkali metabisulphite furnishes 4 4 -tetramethvldiaminodiphenyl telluride, which is slowly oxidised in the air. 

If either the o- or -position is occupied, only one isomer is obtained transformation to the mefo-position does not occur. This is a standard method of preparation of acyl-amino-ketones, or by a further hydrolysis of amino-ketones. The tendency, illustrated in this reaction, of groups to wander from the amino group to the nucleus, is also shown in previous reactions and in the preparation of aminoazobenzene from diazoamino-benzene (Preparation 456), of sulphanilic acid from aniline sulphate (Preparation 292), of o- and p-chloroacetanilides from acetochloranilide (Preparation 328), of o- and p-toluidine from methylaniline hydrochloride, and of 1 2 4-aminodimethylbenzene (2 4-xylidine) from dimethylaniline hydrochloride. 

Amino-dimethylaniline hydrochloride (1 %). Dissolve 1 g p-amino-NN-dimethylaniline dihydrochloride, H2N. C6H4. N(CH3)2.2HC1, in 100 ml water. 

A four-necked 3-1. flask fitted with a thermometer, reflux condenser, dropping funnel, and mechanical stirrer is charged with 750 ml. of n-hexane, 750 ml. of anhydrous ethyl ether, 104 g. (3.25 moles) of anhydrous methanol, and 370 g. (3.05 moles) of A,A-dimethylaniline. A drjing tube is attached to the outlet of the condenser to prevent moisture from entering the reaction vessel. The dropping funnel is charged with 182 g. (1 mole) of freshly distilled arsenic trichloride, and this is added drop by drop to the well-stirred ice-cooled contents of the reaction flask. The temperature in the flask is maintained at ca. -i-5°. During the course of the addition, a white precipitate of A, A -dimethylaniline hydrochloride is formed. 

When the addition of the arsenic trichloride is completed, the reaction mixture is stirred for another 1 to 2 hours at room temperature. The solution is filtered with careful exclusion of the moisture of the atmosphere, and the A, A -dimethylaniline hydrochloride precipitate is washed with cold ethyl ether. The combined filtrates are distilled using a 60-cm. vacuum-jacketed column filled with glass helices. The trimethoxyarsine distills at 129-1307760 mm. yield 129 g. (77%). Yields of 118-126 g. are obtained using triethylamine. 

A hydroxyethylated polymer (0.6 g) was stirred at room temperature with 0.37 ml of chlorodiethylphosphite and 0.33 ml of dimethylaniline in 10 ml of toluene for 20 hr, during which a white precipitate of dimethylaniline hydrochloride appeared. The solution was removed by decantation, and the polymer was washed with 3x20 ml of toluene and 2x30 ml of chloroform (alcohol free) and vacuum dried. Elemental analysis showed that the polymer contained 4.48% P. Reactions with other phosphites and with chlorodiphenylphosphine were carried out similarly. 

Dimethylphenylthiourea has been synthesized by allowing 2,6-dimethylaniline hydrochloride to react with ammonium thiocyanate.14... 

Dry hydrogen chloride reacts with the dichlorophosphine to form a hydrochloride, but prolonged treatment leads to decomposition, with formation of dimethylaniline hydrochloride and phosphorus trichloride. 

C p - lodo - N - dimethylaniline - hydrochloride - hydroiodide - iodine < complex (refined as space group no. 15)... 

The red solution of anthraquinone-l-azo-4-dimethylaniline hydrochloride gives a blue-violet precipitate, (C22H,702N3)2 H2SnCle, with Sn salts in... 

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