The filtrate from the mercury chloride solution was freed from mercury by SH2, evaporated to a syrup, and then extracted with alcohol. From the alcoholic solution platinum chloride precipitated neuridine, this was filtered off, the filtrate freed from alcohol and platinum, and the aqueous solution concentrated to a small volume and precipitated with an aqueous solution of platinum chloride; this precipitated ethylidene platinum chloride. The mother liquor from this precipitate was concentrated on the water-bath, and, on cooling, the platinochloride of muscarine crystallised out. From the mother liquor (freed from the crystals), on standing in a desiccator, the gadinine double salt crystallised out, and from the mother liquor (freed from gadinine after removal of the platinum by SH2) distillation with KHO recovered trimethylamine.
From the platinochloride of ethylenediamine, the chloride can be obtained by treating with SH2, filtering, and evaporating; by distilling the chloride with a caustic alkali, the free base can be obtained by distillation.
Ethylidenediamine is isomeric with ethylenediamine, but differs from it in the following properties:—ethylidenediamine is poisonous, ethylenediamine is non-poisonous.
Ethylenediamine forms a platinochloride almost insoluble in hot water, while the ethylidene salt is more easily soluble. The properties of the gold salts are similar, ethylenediamine forming a difficultly soluble gold salt, ethylidene a rather soluble gold salt.
Ethylidenediamine forms a hydrochloride, C2H8N22HCl, crystallising in long glistening needles, insoluble in absolute alcohol, rather soluble in water. The hydrochloride gives precipitates in aqueous solution with phospho-molybdic acid, phospho-antimonic acid, and potassium bismuth iodide; the latter is in the form of red plates.
The platinochloride, C2H8N22HCl.PtCl (Pt = 41·5 per cent.), is in the form of yellow plates, not very soluble in cold water.
Ethylidenediamine, when subcutaneously injected into guinea-pigs, produces an abundant secretion from the mucous membranes of the nose, mouth, and eyes. The pupils dilate, and the eyeballs project. There is acute dyspnœa; death takes place after some twenty-four hours, and the heart is stopped in diastole.
Trimethylenediamine is believed to have been isolated by Brieger from cultivations in beef broth of the comma bacillus.
It occurs in small quantity in the mercuric chloride precipitate, and is isolated by decomposing the precipitate with SH2, evaporating the filtrate from the mercury sulphide to dryness, taking up the residue with absolute alcohol, and precipitating by an alcoholic solution of sodium picrate. The precipitate contains the picrate of trimethylenediamine, mixed with the picrates of cadaverine and creatinine. Cadaverine picrate is insoluble in boiling absolute alcohol, the other picrates soluble; so the mixed picrates are boiled with absolute alcohol, and the insoluble cadaverine filtered off. Next, the picrates of creatinine and trimethylenediamine are freed from alcohol, the solution in water acidified with hydrochloric acid, the picric acid shaken out by treatment with ether, and then the solution precipitated with platinum chloride; the platinochloride of trimethylenediamine is not very soluble, while creatinine easily dissolves; so that separation is by this means fairly easy.
It also gives a difficultly soluble salt with gold chloride.