Hydrogen chloride-aniline reaction

V-Phenylsuccinimide [83-25-0] (succanil) is obtained in essentially quantitative yield by heating equivalent amounts of succinic acid and aniline at 140—150°C (25). The reaction of a primary aromatic amine with phosgene leads to formation of an arylcarbamoyl chloride, that when heated loses hydrogen chloride to form an isocyanate. Commercially important isocyanates are obtained from aromatic primary diamines. 

Hydrogen cyanide, as the nitrile of formic acid [64-18-6] CH2O2, undergoes many of the typical nitrile reactions. For example, it can be hydrolyzed to formic acid by aqueous sulfuric acid (4) it can be hydrogenated to methylamine [74-89-5], CH N (5) and it can be converted to phenylformamidine [618-39-3], CyHgN2, using aniline and hydrogen chloride (6). 

A mixture of 2.9 grams of 5-chloro-2,4-disulfamvl-aniline in 20 ml of anhydrous diethylene-glycol dimethylether, 0.44 gram of propionaldehyde and 0.5 ml of a solution of hydrogen chloride in ethyl acetate (109.5 grams hydrogen chloride per 1,000 ml) Is heated to 80° to 90°C and maintained at that temperature for 1 hour. The reaction mixture is concentrated under reduced pressure on addition of water, the product separates and is then recrystal-lized from ethanol or aqueous ethanol to yield the desired 6-chloro-3-ethvl-7-sulfamyl-3,4-dihydro-1,2,4-benzothiadiazine-1,1-dioxide, MP 269° to 270°C. 

Triaryl esters can be prepared by a variety of methods. For example, by allowing 3 mol. of the phenol to react with 1 mol. of phosphorus oxychloride for several hours. Organic bases such as aniline, dimethylaniline and pyridine have been used to neutralize the hydrogen chloride formed in the reaction.3 Alternatively, the phenols may be converted into the sodium phenoxides4 and then allowed to react with phosphorus oxychloride. 

Of the primary monoamines, some, such as. aniline, o-toluidine, xylidine, are colourless liquids. Others, such as p-toluidine, pseudo-cumidine and the naphthylamines, are solids. They can be distilled without decomposition and are volatile with steam. In water they are rather sparingly soluble—a 3 per cent solution of aniline can be made. The di- and polyamines are usually solids, not volatile in steam and much more soluble in water than the monoamines. The amines are basic in character, but, as a result of the negative nature of the phenyl-group, the aromatic amines are considerably weaker bases than are the aliphatic amines. Consequently aqueous solutions of the (stoicheio-metrically) neutral aniline salts are acid to litmus because of the hydrolysis which they undergo. For the same reason a small amount of the free base can be extracted with ether from an aqueous solution of an aniline salt. (Test with a solution of hydrogen chloride in ether or, after evaporation of the ether, by the reaction with bleaching powder.)... 

Catalytic hydrogenation of the nitro group of 21 with Raney nickel under hydrogen atmosphere followed by catalyst removal and recrystallization from methanol-water then furnished aniline 22 and set the stage for the ultimate installation of costly biphenyl-2-carbonyl chloride. Selective acylation of the aniline moiety of 22 was readily achieved by treatment with biphenyl-2-carbonyl chloride in a refluxing mixture of pyridine and acetonitrile. Subsequent addition of a solution of hydrogen chloride in ethyl acetate to the cooled reaction mixture resulted in the precipitation of conivaptan HCl (1), which was isolated in 74% yield. 

Pyridine serves to make all the aniline available. It does not prevent combination of hydrogen chloride with the N,N -di-phenylbenzamidine even when two equivalents of pyridine are used. In the presence of pyridine the reaction mixture is a suspension and is easily handled. In the absence of pyridine it solidifies to a cake, which must be pulverized to permit liberation of the amidine from the hydrochloride. 

Ortho-Substitution of anilines, N-Methylaniline is converted by BCI, into N-methylanilinodichloroborane (1), which reacts with a benzaidehyde regio-specifically to form 2. The yield in this reaction is improved considerably by addition of a tertiary amine to trap the hydrogen chloride formed. Actually the reaction can be conducted in a one-pot procedure. The aniline is refluxed with BCI3 in benzene to form 1 then the aldehyde and tertiary amine are added to the solution of 1. This method is not applicable to aniline itself. 

Quinones behave as typical unsaturated ketones and undergo 1,4-addition reactions with acid catalysis. Thus treatment of p-benzoquinone with hydrogen chloride gives a chlorohydroquinone (3.18). The addition of aniline and methanol takes place to give initially the corresponding quinols. However, the electron-donating character of these substituents makes the quinols more easily oxidized by excess p-benzoquinone. The anilino- (3.19) and methoxyquinones (3.20) are therefore the final products. 

In alcoholic solution, lactose reacts with ammonia, aniline, do-decylamine, urea, guanidine, and hydroxylamine, respectively, to give lactosylamine derivatives. W-Octadecyllactosylamine was formed by condensing octadecylamine with lactose in 2-propanol-water (5 3 vol./ vol.) at room temperature. Occasionally, presence of a trace of acidic catalyst, such as ammonium chloride, zinc chloride, or hydrogen chloride may be necessary, especially if the amine is a weak base. p-Amino-phenol and p-phenetidine condense with lactose under such conditions. Condensation of lactose with o-phenylenediamine gives a quinoxaline (41), which is transformed into a flavazole derivative (42) on reaction with phenylhydrazine. The existence of a molecular compound of lactose with... 

F/193°C). Violent reaction with oxidizers. Heat, acids, acid fumes cause decomposition with release of toxic fumes of aniline, hydrogen chloride, and nitrogen oxides. On small fires, use dry chemical powder (such as Purple-K-Powder), foam, or CO2 extinguishers. 

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