Chemical examination of jalap / by Frederick B. Power and Harold Rogerson.

  • Frederick Belding Power
Date:
[1910]
Catalogue details

Licence: Attribution 4.0 International (CC BY 4.0)

Credit: Chemical examination of jalap / by Frederick B. Power and Harold Rogerson. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    Ether and chloroform extracted 19.3 grams and 9 grams respectively of clear, orange-yellow sirups, which did not solidify. Ethyl acetate extracted 54 grams of a dark, opaque sirup, which, when perfectly dry, could be reduced to a light brown powder. The latter was extremely hygroscopic, but if kept in a sealed tube, could be preserved unchanged. Alcohol extracted 88 grams of a product, which formed a hard, brittle mass, and could be reduced to a nearly colorless powder. Each of the above products from the hydrolyzed alcohol extract of the resin was then subjected to treatment with dilute sulphuric acid. Ether Extract of the Hydrolyzed Resin. The entire amount of this extract (19.3 grams) was dissolved in water, and such an amount of sulphuric acid added that the latter represented 5 per cent, by weight of the solution. The whole was then boiled in a reflux apparatus for about 6 hours, when a sirupy product separated which did not become solid on cooling, and the mixture was subsequently distilled with steam. The distillate, which contained a light yellow oil floating on the surface, was extracted with ether, and the ethereal liquid shaken with a solution of sodium carbonate. On evaporating the ether a very small amount of a neutral oil was obtained, which did not respond to the test for furfural and gave no color with ferric chloride. The sodium carbonate liquid was acidified and extracted with ether, the ethereal liquid being washed, dried, and the solvent removed, when 1.2 grams of a light yellow oil were obtained. This was unsaturated, since it ab- sorbed bromine. It was distilled under diminished pressure, when the following two fractions were collected: (I) 120-140°; (II) i40-i6o°/i5 mm., the latter distilling for the most part at about i6o°/i5 mm. The first fraction was analyzed with the following result: I. 0.1480 gave 0.3534 C02 and 0.1362 H20. C = 65.1; H = 10.2. C7H]202 requires C = 65.6; H = 9.4 percent. The remaining portion of this liquid yielded a fraction of silver salt which gave the following result on analysis: 0.1494 gave 0.2342 C02, 0.0796 H20, and 0.0590 Ag. 0 = 42.7; 11 = 5.9; Ag =39.5. CIOH1702 Ag requires C = 43.3; H = 6.1; Ag = 39.0 per cent. Fraction I thus apparently consisted of a mixture of an acid C10H18O2 with one of lower molecular weight. II. 0.1560 gave 0.3978 C02 and 0.1516 H20. C = 69.5; H = 10.8. Ci8Hi»02 requires C = 70.6; H = 10.6 per cent. From the remainder of this fraction a silver salt was prepared and analyzed. 0.1270 gave 0.2000 C02, 0.0746 HaO, and 0.0492 Ag. 0 = 43.0; H = 6.5; Ag = 38.7. C,.H1t02 Ag requires C = 43.3; H = 6.1; Ag = 39.0 per cent.