Hydrogen chloride solutions

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. 

A solution of 1.0 gram of 10-[3 -(N-acetoxyethylpiperazinyl)-propyl]-2-trifluoromethyl-phenothiazine in 25 ml of 1 N hydrochloric acid is heated at reflux briefly. Neutralization with dilute sodium carbonate solution and extraction with benzene gives the oily base, 10-[3 -(N-(3-hydroxyethylpiperazinyl)-propyl]-2-trifluoromethylphenothiazine. The base is reacted with an excess of an alcoholic hydrogen chloride solution. Trituration with ether separates crystals of the dihydrochloride salt, MP 224° to 226°C, (from U.S. Patent 3,058,979). 

The combined filtrate and washes were concentrated to 1.6 liters and the concentrate containing the dl-2-(N-methylamino)isocamphane washed once with about 350 cc water, and then dried over anhydrous sodium sulfate. The dried ether concentrate was then cooled in an ice bath and with stirring a cold saturated ethereal-hydrogen chloride solution was added slowly until acid to Congo red required, about 440 ml anhydrous ether saturated (at 0°C) with HCI gas. After precipitation was complete, the white crystalline dl-2-(N-methylamino)isocamphane hydrochloride was filtered, and washed with anhydrous ether... 

A solution of 1.7 g of 2-hydroxymethyl-3-benzyloxy-(1-hydroxy-2-tert-butyl-aminoethyl)py-ridine in 30 ml of methanol containing 1.2 ml of water is shaken with 700 mg of 5% palladium-onatmospheric pressure. In 17 minutes the theoretical amount of hydrogen has been consumed and the catalyst is filtered. Concentration of the filtrate under reduced pressure provides 1.4 g of the crude product as an oil. Ethanol (5 ml) Is added to the residual oil followed by 6 ml of 1.75N ethanolic hydrogen chloride solution and, finally, by 5 ml of Isopropyl ether. The precipitated product is filtered and washed with isopropyl ether containing 20% ethanol, 1.35 g, melting point 182 (dec.). 

The conductivity of a 0.1 M acetic acid solution is much lower, however, than that of a 0.1 M hydrogen chloride solution. This and other experiments show that only a small fraction of the dissolved acetic acid, CH3COOH, has formed ions. Such a substance that dissolves and dissociates to ions only to a limited extent is called a weak electrolyte. 

The vapor pressures (fugacities) shown in Figure 6.14 were reported by J. J. Fritz and C. R. Fuget, Vapor Pressure of Aqueous Hydrogen Chloride Solutions", Chem. Eng. Data Ser., 1, 10-12 (1956). The vapor pressures are too small to measure directly. The values reported were calculated from the results of emf measurements made on an electrochemical cell. In Chapter 9, we will describe this and other cells in detail. 

When the filter cake contains hydrogen chloride, it is very hygroscopic. It should therefore be covered immediately with dry ether after the ethereal hydrogen chloride solution has been aspirated. 

Hydrogen chloride solutions, 13 828 Hydrogen chloride-water system,... 

Tin(n) and Tin(IV) Sulphides. Pass a stream of hydrogen sulphide through hydrogen chloride solutions of tin (I I) and tin(IV) chlorides in separate test tubes. What is the colour of the sulphide precipitates Write the equations of the reactions. 

This product crystallises in bright green prisms, M.pt. 166° to 167° C., having a metallic lustre, but in powder form or in solution it is intense red. It is readily soluble in acetone, chloroform, acetic acid, warm benzene, alcohol or carbon tetrachloride. By adding an absolute ether hydrogen chloride solution to a chloroform solution of the anil, a brown crystalline salt is obtained which soon deliquesces in the air. The anil is soluble in concentrated sulphuric acid with decomposition, giving a dark red solution. 

Aminomethylene derivatives may be prepared by reacting the pyrido [1,2-a]pyrimidines (63 R = H) with aminomethanols in ethereal hydrogen chloride solution or with amines and paraformaldehyde.295... 

Precautions should be taken to prevent absorption of atmospheric moisture by the hydrogen chloride solution. The dropping funnel should be closed or protected by a calcium chloride tube. 

The free base may be converted, with isopropanolic hydrogen chloride solution, into the hydrochloride form, melting point 177°C (from propanol). 

Phosphorylation of XLVII with phosphorus oxychloride in pyridine solution, followed by hydrolysis to remove the methyl and isopropylidene residues, gave D-ribose 5-phosphate (XLVIII) which, as its barium salt, was found to be identical with the barium salt of the D-ribose phosphate from inosinic acid. By way of further confirmation of the structure of D-ribose 5-phosphate, Levene, Harris and Stiller129 showed that in methanolic hydrogen chloride solution both the natural and synthetic material mutarotated in a manner characteristic of a sugar which can form only a furanoside. 

Fatty acid analysis of a fat is nowadays a relatively routine analytical operation. After methylation of the fat using reaction with boron trifluoride/methanol, boron trichloride/methanol, methanolic hydrogen chloride solution, diazomethane or, if free fatty acids are not present, alkaline catalysts such as sodium methoxide/methanol, the prepared methyl esters are then analysed by GC on a polar column such as CpSil 88, BPX70 or SP2340. The high polarity of the column is necessary to separate the saturated and unsaturated fatty acids fully. The fatty acid composition of a milk fat sample is thus relatively easily obtained, and was therefore one of the first techniques investigated for authentication purposes. 

Chloroprene monomer production starts with the catalytic conversion of acetylene to monovinylacetylene, which is purified and subsequently reacts with aqueous hydrogen chloride solution containing cuprous chloride and ammonium chloride to give chloroprene.61... 

A double drum system operates with a high tower top temperature that is above the dew point of the water-hydrogen chloride solution. A heat exchange with crude or another stream condenses only hydrocarbon in the first drum. This hydrocarbon, usually called heavy naphtha, is a hot reflux that controls... 

Hydrogen ferrocyanide, Ferro-cyanic acid, H4[Fe(CN)6], is conveniently prepared by adding concentrated aqueous hydrogen chloride solution to a saturated solution of potassium ferrocyanide, m the cold —... 

Similar photolytic cyclizations which are usually carried out in methanolic hydrogen chloride solution can yield either benzimidazoles or the iV-oxidcs, depending on the natures of the tertiary amino group and the ring substituents [ 161 ]. Undcr more vigorous reaction conditions (or in the presence of reducing agents), AyV-dialkyl(or aralkyl)-o-nitroanilines are converted into benzimidazoles (61) rather than the iV-oxides (Scheme 2.1.25). 

Under neutral conditions and at high temperatures ca. 180 °C) nitriles react with water to give amides (equation 20). ZnO and CdO are efficient catalysts. To accelerate the reaction rate, acid treatment under a variety of conditions can be carried out hydrochloric acid, hydrogen chloride or bromide in formic acid, alcoholic hydrogen chloride solutions, polyphosphoric acid - and boron trifluoride in aqueous acetic acid are all effective. 

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