The chemistry of the bark of Robina pseud-acacia, Linné (false acacia or common locust) / by Frederick B. Power.

  • Power, Frederick B. (Frederick Belding), 1853-1927
Date:
[1901]
Catalogue details

Licence: In copyright

Credit: The chemistry of the bark of Robina pseud-acacia, Linné (false acacia or common locust) / by Frederick B. Power. Source: Wellcome Collection.

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    acidulated, still afforded a strong alkaloidal reaction, but it was evident that during contact with the alkali the basic sub¬ stance was being continually decomposed with the evolution of ammonia. (b) This liquid was treated in the same manner as described under (a), and, although originally nearly colourless, when al¬ lowed to evaporate in a vacuous desiccator it afforded an almost black residue. The latter, when treated with absolute alcohol, left ia crystalline residue of ammonium chloride, and from the alcoholic solution a small amount of a platinum salt was obtained, which, on analysis, also gave figures agreeing with those required for ammonium chloride. 0-0405 gramme of the salt gave on ignition 0‘0180 gramme of platinum, or 44'4 per cent. Pt. (c) This liquid, which seemed to be the purest of the three fractions, was treated in the same manner as the two preceding ones. The residue left on evaporation contained some crystals of ammonium chloride, and the platinum salt obtained from the alcoholic solution was analysed with the following result: O'056 gramme of the salt gave on ignition 0-021 gramme of platinum or 37‘5 per cent. Pt. It is possible, therefore, that this fraction contained one of the methylamines, or a mixture of these bases. The amorphous brown residues which remained on treating the alcoholic mercuric chloride precipitates with water were suspended in water and decomposed by hydrogen sulphide. The filtrate was very dark in colour, gave precipitates with alkaloidal reagents, and also developed ammonia when heated with a caustic alkali. On evaporation it left simply a dark amorphous residue. The alcoholic liquid remaining after precipitation with alco¬ holic mercuric Chloride was treated with hydrogen sulphide to remove the excess of mercury, and filtered. After distilling off the alcohol, a little water was added, and the liquid further evaporated, when a peculiar disagreeable odour was developed, and a considerable amount of a black resin separated. After purifying the very dark-coloured liquid by means of lead subace¬ tate it still afforded a strong alkaloidal reaction. It was finally made strongly alkaline with potassium hydrate, distilled, and the distillate collected in water acidulated with hydrochloric acid. On evaporating the acid distillate to dryness, and treating the residual salt with absolute alcohol, a considerable amount of ammonium chloride was left undissolved. The alcoholic solu¬ tion, after evaporating and again taking up the residue with alcohol, afforded a small amount of a platinum salt which was