Hydrochloric acid gas

In a 3-I. round-bottomed flask are placed 500 cc. (400 g., 8.7 moles) of absolute alcohol which has been saturated in the cold with hydrochloric acid gas (Note i), 870 cc. (6S0 g., 20 moles) of 96 per cent alcohol (Note 2) and 70 g. (1.03 moles) of methyleneaminoacetonitrile (Note 3). This mixture is refluxed on a steam bath for three hours (Note 4). During the refluxing, ammonium chloride separates. After the reaction is complete, the hot alcohol solution is filtered with suction and the filtrate cooled, thus allowing the glycine ester hydrochloride to separate out in fine white needles. The product is filtered with suction, sucked as dry as possible on the filter, and then allowed to dry in the air. The yield is about no g. The alcohol from the filtrate is distilled (Note 5) until about one-third of its volume is left and again cooled and a second crop of crystals is obtained. The total yield of product, m.p. 142-143, varies from 125 to 129 g. (89-91 per cent of the theoretical amount). If a very pure product is desired, it may be recrystallized from absolute alcohol. 

The possibility of the existence of organosilicone compounds was first predicted by Dumas in 1840, and in 1857 Buff and Wohler found the substance now known to be trichlorosilane by passing hydrochloric acid gas over a heated mixture of silicone and carbon. In 1863 Friedel and Crafts prepared tetraethylsilane by reacting zinc diethyl with silicon tetrachloride. 

Detection and result The chromatogram was freed from mobile phase in a stream of warm air and exposed to hydrochloric acid gas (Linde) in a Teflon autoclave (diameter 20 cm, height 8 cm). For this purpose the HPTLC plate was laid on a... 

Tile tartaric acid is finely powdered and mi.Ked with half the above quantity (80 c.c.) of absolute alcohol. The mixture is heated on the water-bath with upright condenser until dissolved. The flask is immersed in cold water, and the well-cooled solution saturated with dry hydrochloric acid gas (prepared in the usual way by dropping cone, sulphuric acid into cone, hydiochloric acid, see Fig. 65, p. 93). After standing for an... 

By the action of hydrochloric acid gas on sabinene dissolved in acetic acid, terpinene dihydrochloride is produced, melting at 52°. If no trace of moisture is present the monohydrochloride alone is yielded. 

Limonene forms a monohydrochloride, which is a liquid, and which exists in both optically active modifications. By the action of moist hydrochloric acid on the acetic or alcoholic solution of limonene, no optically active dihydrochloride is formed, the terpene becoming inactive and dipentene dihydrochloride, C (,H,g2HCl, results. This body is prepared when limonene is mixed with half its volume of glacial acetic acid, and a current of hydrochloric acid gas is passed over (not into) the well-cooled liquid, with frequent shaking. The resulting mass is pressed on a porous plate, dissolved in alcohol, and precipitated with water. It melts sharply at 50°. 

To prepare natural sylvestrene, the fraction of Swedish oil of turpentine boiling between 175° to 180° is diluted with an equal volume of ether which has been previously saturated with hydrochloric acid gas. The mixture is allowed to stand for two or three days, the ether distilled off, and the residue is left in a very cold place for some months, when sylvestrene dihydrochloride is obtained. This body, CjeHig2HCl, when recrystallised from alcohol melts at 72° and has an optical rotation [a]o = + 22°. If this body be distilled with aniline it yields sylvestrene, which has the following characters —... 

If a current of hydrochloric acid gas be passed through an ice-cold solution of the sesquiterpene dissolved in ether a crystalline trihydrochloride is obtained, which melts at 79° to 80°, and has the formula C15H24.3HC1. 

Zingiberene forms a dihydrochloride, CigHj, 2HC1, when its solution in an equal volume of glacial acetic acid is saturated at 0° with dry hydrochloric acid gas. It crystallises from hot alcohol in fine white needles melting at 168° to 169°. 

The fraction of oil of cade boiling at 260° to 280° is converted into cadinene dihydrochloride by saturating its solution in dry ether with dry hydrochloric acid gas. The hydrochloride is separated, dried, and leorystallised, and the hydrochloric acid removed by heating it with aniline or with sodium acetate in glacial acetic acid. The liberated cadinene is rectified in a current of steam. Cadinene from oil of cade is highly laevo-rotatory, the dextro-rotatory variety being obtained from Atlas cedar oil and West Indian sandalwood oil. 

Caryophyllene dihydrochloride, Cj5H24.2HCl, may be obtained by saturating a quite dry ethereal solution of the sesquiterpene with dry hydrochloric acid gas, and exposing the mixture to very intense cold. It melts at 69° to 70°. 

The most recent work, however, on the sesquiterpene is that of fiemmler and Eisse. From the crude selinene, prepared hy fractional distillation, they prepared the crystalline dihydrochloride, Cj5H24.2HC1, melting at 72° to 74°, by passing a mixture of 1 part of dry hydrochloric acid gas with 3 parts of air, into the sesquiterpene dissolved in ether. This compound on digestion at very gentle heat, with a solution of caustic potash in methyl alcohol, yields selinene, which the authors conclude is a doubly unsaturated bicyclic compound. The characters of the selinene thus obtained are as follows —... 

When rectified gurjun balsam oil, that is, a mixture of a- and /3-gurjunene, is saturated in ethereal solution with hydrochloric acid gas, and the mixture is left standing for two days at room temperature, and the hydrochloric acid abstracted by heating with sodium acetate, the regenerated sesquiterpene appears to be a bicyclic compound having the following characters —... 

The fraction of opoponax oil boiling at 135° to 137° in vacuo contains a sesquiterpene, which has been examined by Schimmel Co. On fractionation at ordinary pressure, it boiled at about 260° to 270°, and in this impure condition was dissolved in ether and saturated with hydrochloric acid gas. The crystalline hydrochloride which resulted melted at 80°, and was optically inactive. It has the composition. 3HC1. 

Geraniol is converted into the isomeric alcohol, linalol, hy heat, and both alcohols yield the same chloride when treated wijth dry hydrochloric acid gas. Dupont and Labaune first prepared this chloride, which they considered was linalyl chloride, but Eorster and Cardwell have shown that it is geranyl chloride. 

Ethyl Benzoate.—This ester has not been found, so far, to occur naturally in essential oils. It has, however, been prepared by synthetic processes, for example, by condensing ethyl alcohol with benzoic acid by means of dry hydrochloric acid gas. Its odour is very similar to that of methyl benzoate (q.v.), but not quite so strong. It is an oil of specific gravity I OfilO, refractive index 1 5055, and boiling-point 213° at 745 mm. It is soluble in two volumes of 70 per cent, alcohol. 

Ethyl Cinnamate.—The cinnamic ester of ethyl alcohol is a natural constituent of a few essential oils, including camphor oil and storax. It is formed synthetically by condensing cinnamic acid and ethyl alcohol by dry hydrochloric acid gas. It has a soft and sweet odour, and is particularly suitable for blending in soap perfumes. It is an oil at ordinary temperatures, melting at 12°, and boiling at 271°. Its specific gravity is 1 0546, and its refractive index 1 5590. 

Amyl Benzoate.—This ester has the formula C Hjj. (02C)(C H5). It is one of the best fixatives known, and has a slight but distinct amber odour. It is prepared by condensing amyl alcohol and benzoic acid with dry hydrochloric acid gas. 

Salzsaure-gas, n. hydrochloric acid gas. -18-sung,/. hydrochloric acid solution. 

The hydrochloride of MP 223°-225°C is obtained by dissolving the base with alcohol and the corresponding quantity of hydrochloric acid gas in the hot with subsequent cooling of the solution. Colorless crystals are formed of MP 223°-225°C, which are easily soluble in water. 

Introduce 33.6 g (0.2 mol) of 1,3 -trimethoxybenzene and 100 ml of chlorobenzene Into a 500 ml three-neck flask with stirrer, hydrochloric acid bubbler and condenser. Stir to dissolve and edd 27.7 g of 4-pyrro idinobutyronitrile (from 4hydrochloric acid gas in for 4 hours. Cool to about 5°C and add 200 cm3 of water, g ir. Decanttheaqueouslayer,wash again with 150cm3 of water. Combine the aqueous layers, drive off the traces of chlorobenzene by distilling 150 cm3 Qf water, and heat under reflux for one hour. Cool and render alkaline by means of 60 ml of sodium hydroxide solution of 36° Baume. Extract twice with 100 ml of ether. Wash the ether with 100 ml of water. Dry the ether over sodium sulfate and slowly run in 50 ml of 5N hydrogen chloride solution in ether, at the boil. Cool in ice. Filter, wash with ether and dry in a vacuum oven. 33.6 g of crude product are obtained. Recrystallize from 200 ml of isopropanol in the presence of 3 SA carbon black. Filter. Wash and dry in a vacuum oven. 

Next the xylene was distilled away, the liquid residue dissolved in about 80 ml carbon tetrachloride and the hydrochloride precipitated through introduction of hydrochloric acid gas. The hydrochloride was dissolved in about 100 ml acetone and the solvent subsequently distilled away, whereby excess hydrochloric acid passed over with it. This operation was repeated until no excess acid was present. 

In Britain, Leblanc pollution went uncontrolled for decades. A visitor outside Liverpool, a major Leblanc factory center, described in 1846 a sordid ugly town. The sky is a low-hanging roof of smeary smoke. The atmosphere is a blend of railway tunnel, hospital ward, gas works and open sewer. The features of the place are chimneys, furnaces, steam jets, smoke clouds and coal mines. The products are pills, coal, glass, chemicals, cripples, millionaires and paupers. An estimated 40,000 men, women, and children— many of them Irish escaping the potato famine—worked in British Leblanc factories. Until 1875, workers stirred batches of chemicals in a cloud of hydrochloric acid gas. Their teeth decayed, and their clothing burned. Inhaling deeply could make them faint and vomit. 

In 1863, the British Parliament passed the Alkali Act, which forced the LeBlanc factories to reclaim 95 percent of the hydrochloric acid gas that they produced. Angus Smith, the Alkali Inspector assigned to enforce the law, demonstrated that industrial towns suffered from higher sulfate levels than did the countryside. When Angus Smith also coined the term acid rain, air pollution became a public issue. By the 1870s, Leblanc factories emitted less than 0.1 percent of the hydrochloric acid gas they produced the rest was reclaimed and sold. 

Surprisingly, Britain s hard-fought reforms cost factory owners little. The summer after an industrialist spent 300 to install the towers required by the Alkali Act, nearby fruit trees that had not blossomed in years bloomed and roses grew. Unfortunately, reformers could not convince the government to ban the release of hydrogen sulfide too new technology could control the release of hydrochloric acid gas, but not hydrogen sulfide gas. 

In the Ruthner process,1 the WPL is first concentrated in an evaporator. The concentrate is then pumped to a reactor where it is combined with hydrochloric acid gas, in which ferrous chloride and sulfuric acid are formed. The sulfuric acid is then separated by centrifuging. The ferrous chloride... 

Ethyl phenylacetate may be prepared by the treatment of benzyl cyanide with alcohol and hydrochloric acid gas.1 It is much more convenient in the laboratory, however, to use sulfuric acid in place of hydrochloric acid in fact, the yields obtained are better than those recorded in the literature. This ester may also be made by the esterification of phenylacetic acid with hydrochloric acid and alcohol 2 or with alcohol and sulfuric acid 3 the following less important methods of preparation may be mentioned the action of benzyl magnesium chloride upon ethyl chlorocarbonate,4 and the action of copper on a mixture of bromobenzene and ethyl chloroacetate at 1800.5... 

Acetone Ethyl Mercaptan. 50 g of ethyl mercaptan are added to 20 g of acetone and 6 g of anhydrous calcium chloride. Dry hydrochloric acid gas is passed into the reaction, while the temp is controlled to 25°, by external cooling. When saturated with acid, the mixture is allowed to stand for 12 hours, and is then washed with water. The resulting mercaptol is separated, dried with calcium chloride, and fractionally distilled. Unreacted ethyl mercaptan passes over first and is saved for a second run. Next, the mercaptol passes over at about 190°. 

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