Containing hydrogen chloride

Although 16-methylene-17a-hydroxy-20-ketopregnanes can be brominated at C-21 in excellent yield in chloroform containing a small amount of methanol,with A -17a-hydroxy-20-ketopregnanes the use of ethanol alone (containing hydrogen chloride) is far superior. Isolated double bonds (e.g., A, A ) may also be protected prior to bromination by the addition of chlorine. 

Methods have been developed for perchloric acid synthesis which involve the electrolysis of solutions containing hydrogen chloride or molecular chlorine. These processes occur at high anode potentials (2.8 to 3.0 V vs. SHE), when oxygen is evolved at the anode in parallel with perchloric acid formation. The current yields of perchloric acid will increase considerably when the reaction is conducted at low temperatures (e.g., 20°C). 

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. 

HARTZELL ET AL. Toxicity of Smoke Containing Hydrogen Chloride... 

Hartzell, G.E. Grand, A.F. Switzer, W.G. "Modeling of Toxicological Effects of Fire Gases VI. Further Studies on the Toxicity of Smoke Containing Hydrogen Chloride," J. Fire Sciences 1987, 5(6), 368-391. 

Reaction of 4a with furan also proceeds in HF1P containing hydrogen chloride at 0 °C to yield a cyclopentenone product 26 as well as the products obtained in the reaction with Lewis acid, 23 and 24 (entries 7-9). The formation of cyclopentenone product 26 did not occur when less than one equivalent of furan was employed a simple cyclopentenone product 25 was obtained instead (entry 7). Addition of THF also retarded the formation of 26 in the reaction in HFIP as solvent with an increasing yield of 25 (entry 10). Preferential formation of the [4 + 3] cycloadduct 23 was observed without formation of 26 in the reaction of 4b in HFIP (entries 11 and 12) as was observed with Lewis acid in dichloromethane (entries 3-5). Reaction of 4c in HFIP gave 26 (entry 13), with a product distribution similar to that of 4a in HFIP. 

The undistilled compound may contain hydrogen chloride and Me3SiOSiMe3-... 

Also, nucleophilic reagents, alcohols, and acetic acid may be added across the double bond under acid catalysis. Compounds 193 and 198 react114,115 with methanol containing hydrogen chloride, to afford stereoisomeric tetrahydro-2,4-dimethoxypyrans (218 and 219, respectively). In this way, methyl a-DL-oleandroside (221) and methyl a-DL-cymaroside (222) were obtained79,116 from methyl 4-0-benzyI-2,3,6-tri-deoxy-a-DL-erythro-hex-2-enopyranoside (220). 

When glucose is treated with methanol containing hydrogen chloride, and prolonged heat is applied, acetals are formed. In this reaction the hemiacetal function is converted to the monomethyl acetal. 

Nitriles also can be reduced to imines with stannous chloride in ethyl acetate containing hydrogen chloride [26]. The imines are isolated as the stannous chloride salt. 

Dissolution in Water. Close the bottle containing hydrogen chloride with a stopper provided with a capillary facing inward. Invert the bottle with the gas and immerse its neck in a bath with water (see Fig. 53b). Explain what occurs. 

Potassium perchlorate and ammonium perchlorate permissible explosives, cooled by means of common salt, ammonium oxalate, etc., and containing either ammonium nitrate or alkali metal nitrate with or without nitroglycerin, are used in England, Belgium, and elsewhere. They possess no novel features beyond the explosives already described. Explosives containing ammonium perchlorate yield fumes which contain hydrogen chloride. Potassium perchlorate produces potassium chloride. 

In terms of corrosion, the occurrence of chlorine in coal leads to the formation of hydrogen chloride, and the condensation of water containing hydrogen chloride (hydrochloric acid) on the cooler parts of combustion equipment can lead to severe corrosion of the metal surfaces. 

C. B. Purves and C. S. Hudson, The analysis of gamma-methylfructoside mixtures by means of invertase. IV. Behaviour of sucrose in methyl alcohol containing hydrogen chloride, J. Am. Chem. Soc., 56 (1934) 1973-1977. 

The chloroform layer was dried and evaporated to remove the solvent. The residue was dissolved in acetone, and an ethanol solution containing hydrogen chloride was added thereto producing 1.53 grams of 2-(4-methoxyphenyl)3-acetoxy-5-(p-dimethylaminoethyl)-2,3-dihydro-l,5-benzothiazepin-4(5H)-one hydrochloride having a melting point from 187° to 188°C. 

Methyl-5-tosyl-L-arabofuranosides (a/3 mixture) (XXXI) on condensation with acetone containing hydrogen chloride gave the 1,2-iso-propylidene derivative (XXXII). Methylation gave 1,2-isopropylidene-3-methyl-5-tosyl-L-arabofuranose (XXXIII) from which the tosyl... 

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