A problem in optical isomerism . s of HOI with the subsequent splitting off of NH4CIJQ JOH 0 (5) E2N G NHg-HCl+HCl—>H2N—G iVd2 HQ1—> EtH — 0^-01 01 IiH4 CI. The formation of chlor-f ormamide by the addition of HOIto cyanic acid was held in disfavor because several students inthis laboratory had been unable to obtain any of the product by n V/ohlers method: H (4) 1—1=0=0+HG1-* H C 01 In the first experiments dry hydrochloric acid gas waspassed over 10 grams of powdered urea in a 150 glass retort. The gas was passed in from 1/2 to 5 hours, then the retort washeated on an oil bath and
A problem in optical isomerism . s of HOI with the subsequent splitting off of NH4CIJQ JOH 0 (5) E2N G NHg-HCl+HCl—>H2N—G iVd2 HQ1—> EtH — 0^-01 01 IiH4 CI. The formation of chlor-f ormamide by the addition of HOIto cyanic acid was held in disfavor because several students inthis laboratory had been unable to obtain any of the product by n V/ohlers method: H (4) 1—1=0=0+HG1-* H C 01 In the first experiments dry hydrochloric acid gas waspassed over 10 grams of powdered urea in a 150 glass retort. The gas was passed in from 1/2 to 5 hours, then the retort washeated on an oil bath and the flow of HOI increased. At about 80°fusion was complete. The temperature was kept low for so longbecause it was thought to favor reaction (3) and disfavor (2). Onsome occasions the HG1 was bubbled through the liquid. As thetemperature increased the liquid became solid and at 120° - 150°a violent reaction took pierce in which white fumes wore driven intothe receiving vessel. The temperature of the oil bath was in-. In-creased to 200°. Chlor-formamide distilled over. In an attempt to improve the yield a flask containingconcentrated sulphuric acid was added to the train. The finalform of apparatus is shown in the figure. LTo change in pressure,substitution of calcium chloride for sulphuric acid as a dryingagent, or regulation in the time of passing HOI or heating on theoil hath produced much effect on the yield of chlor-fbrmamide-about 2 from 10 grams of urea. To test for the presence of the di-hydrochloride (equa-tion 3) HC1 was passed until the mass in the retort had completelysolidified. The product was then carefully removed and no means could more than aboxit 6 grams of HG1 (equivalent toone mole) he added to the 10 grams of urea. Therefore the courseof the reaction is the formation of the mono-chloride by equation(1) its decomposition, by equation (2), and the addition of E01to cyanic acid to form chlor-formamide. The oil bath was aband-oned
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Keywords: ., bookcentury1900, bookdecade1910, booksubjecttheses, bookyear1917
