manner as an amorphous pink precipitate, which gradually changes to a mass of red needles. The nickel and mercuric salts are white and amorphous; the former dissolves readily in hot water, separating again on cooling as a greenish amorphous crust. The copper salt is blue, and dissolves readily in water, differing, therefore, from the copper salt of the original nitro-compound, which is pink, and is quite insoluble in water. The bismuth salt crystallises from hot water, in which it is readily soluble, in the form of glistening white needles. In solutions of the potassium salt, ferric chloride produces a yellowish-brown coloration, so that this reagent serves as a test of the purity of the isonitro-compound, a trace of its isomer producing at once a distinct purple colour. When -bromo-a-isonitrocamphor is heated with fuming nitric acid, it undergoes no great change, the substance merely liquefying, and it may be ultimately recovered, even after some hours; if, however, the nitric acid is more dilute (sp. gr. = 1.3), it dissolves at once, and, after half an hour's boiling, the solution, as it cools, deposits minute, well-defined crystals. These melt at 215°, and are practically pure -bromocamphoric acid. In order to determine whether the nitro-derivative was unsaturated, its behaviour towards bromine, in weak solution, and dilute potassium permanganate was studied. It was found that in chloroform solution the colour imparted by a trace of bromine was not destroyed, even after two days' time; moreover, a dilute solution of potassium permanganate was only decolorised slowly by a faintly alkaline solution of the sodium salt. Behaviour of π-Bromo-a-isonitrocamphor with Acetyl Chloride.—When this substance is added to acetyl chloride, interaction occurs, and bubbles of hydrogen chloride are slowly given off; the action may be completed by warming the mixture on the water-bath during 30 minutes. On pouring the solution into cold dilute soda, a white, crystalline precipitate is obtained, only sparingly soluble in alcohol, and even less readily in ethylic acetate, benzene, or ether; it appears to be quite insoluble in hot water. It was crystallised from alcohol, dried at 100°, and analysed. The results agreed with those required by a monacetyl derivative of a nitrobromocamphor. 0.2012 gave 0.3360 CO2 and 0.0974 H2O. C = 45·54; H = 5·37. C12H16BRNO, requires C 45 28; H 5.03 per cent. = = Acetyl--bromo-a-isonitrocamphor crystallises from alcohol in elongated, six-sided, orthorhombic plates, the optic axial plane being parallel to the large face. Reduction of -Bromo-a-isonitrocamphor.--The experiments made with the original nitro-compounds having served to show that sodium amalgam was the most suitable reducing agent, attempts were made to effect the reduction of its isomer by a similar process. It was found, however, that reduction took place to a very slight extent, if at all; and other reducing agents which were tried also failed to give the desired amido-compound, except in small quantities. In one experiment, however, a dilute solution of the substance in acetic acid was shaken at intervals during a week, with a large excess of zincdust; the solution was then filtered, saturated with hydrogen sulphide, separated by filtration from zinc sulphide, and evaporated. Au oily residue was thus obtained, which, on heating with caustic soda, evolved an ammoniacal odour. It was therefore evaporated two or three times with hydrochloric acid, the oily product dissolved in alcohol, and the solution mixed with several times its bulk of ether; the substance which was subsequently deposited proved to be the hydrochloride of a base, identical with that obtained by a somewhat similar treatment of the original nitro-compound. The following observations were made with the specimen first prepared, the quantity of that obtained in the second instance serving merely for the purpose of identification. The base itself was not isolated; it was found, however, that if the crystals of the hydrochloride were covered with strong ammonia, they disappeared, and were replaced by a waxy substance, readily soluble in water and in ether; this in all probability was the free bromisoamidocamphor. The hydrochloride is excessively soluble in water, and rather soluble in ethylic alcohol; from the latter, it separates in the form of long, colourless, transparent needles, which appear to contain water of crystallisation, as when exposed to the air they gradually become opaque, finally falling to a white powder. Like most amine hydrochlorides, it has a tendency when in solution to undergo slight decomposition, gradually becoming dark brown. When heated with chloroform and caustic potash, it evolves a pungent odour, resembling that of carbylamines. When boiled in ammoniacal solution with silver nitrate, it reduces the latter, metallic silver being deposited. When slowly heated, it melts, and decomposes at 238-239°. A determination of the halogen (I) by Carius' method, and (II) an estimation of the chlorine by direct precipitation with silver nitrate, gave the following results. I. 0·1037 gave 0·1222 AgCl + AgBr. Cl + Br= 41.06. II. 0.0495 0.0262 AgCl. CI = 13.09. CHOВr NH2,HCl requires Cl + Br = 40·88; Cl = 12.57 per cent. The platinochloride is obtained as a pale-yellow, granular precipitate on adding platinum tetrachloride to a solution of the hydro chloride. It is soluble in water and alcohol, being deposited from the latter in the form of transparent, yellow, or brownish-yellow octahedra. It melts and decomposes at 220-230°. Chemical Department, City and Guilds of London Central Technical College. XXXII.-Note on the Formation of Camphorquinone from a-Chloronitrocamphor. By ARTHUR LAPWORTH, D.Sc. DURING the course of the examination of #a-dibromonitrocamphor, undertaken by the author in conjunction with Dr. Kipping, it was observed that this substance undergoes a sudden and somewhat violent decomposition when heated, nitrous fumes, mixed with bromine, being evolved. The product was obviously a mixture, but its study was out of the question, owing to the difficulty of obtaining sufficient material for investigation. As any facts relating to the properties of camphor derivatives are of interest, it was thought worth while to examine the behaviour of the analogous a-bromonitrocamphor and a-chloronitrocamphor, which may be readily obtained in quantity. On referring to the literature on the subject, it was found that Cazeneuve and Morel (Bull. Soc. Chim., 1885, 44, 165) had already stated that these substances are decomposed by heat, nitrous fumes and halogen being liberated. The examination of the products, however, was not carried out, or failed to yield any results of interest, a-Bromonitrocamphor, CoHBrO (NO2), is knowu to contain the group -CBr(NO2) CO-; it is non-acidic, but on reduction yields a-nitrocamphor, C10H15O NO2, which possesses a marked acidic character, and, therefore, contains the group -CH(NO2)-, the latter substance on oxidation yielding camphoric acid, CH(COOH)2. a-Bromonitrocamphor is, therefore, in this respect analogous in constitution to the bromonitroketonaphthalenes obtained by Armstrong and Rossiter (Proc., 1887, 144), by acting on 1: 2-bromonaphthols with fuming nitric acid. These compounds, like a-bromonitrocamphor, lose bromine on reduction, yielding nitro-derivatives; when they are heated, both bromine and nitric oxide are evolved, the corresponding 1: 2-diketocompounds or ß-naphthaquinones being produced. Thus, 13' 2-dibromonaphthol, on treatment with nitric acid, gave a dibromonitroketonaphthalene, which finally afforded 3'-bromo-ß naphthaquinone, If a-bromonitrocamphor were to decompose in like manner, it already been prepared, and fully characterised by Claisen (Ber., 1889, 22, 530), who obtained it from isonitrosocamphor by two methods, namely, by the action of nitrous acid, and by heating it first with sodium hydrogen sulphite, and subsequently with dilute sulphuric acid. The decomposition of a-bromonitrocamphor was found to be almost explosive in character; the product was oily, and appeared to contain very little of the expected substance. The examination of a-chloronitrocamphor, on the other hand, gave more satisfactory results, and, as its decomposition took place less suddenly, it was chosen for examination. The product obtained from it was a black, tarry solid which, on distillation, yielded an orange-coloured, waxy mass; this, on standing, became bespangled with minute, yellow crystals, but it was found impossible to separate the quinone by fractional crystallisation; ultimately, however, the following method of separation was devised, which yielded a small quantity of the quinone in a pure condition. a-Chloronitrocamphor was introduced into a capacious retort in quantities of not more than 2 grams at a time, heat being applied after each addition, and the heating was continued until the vigorous disengagement of gases was at an end; the retort was finally heated during several hours at 200° in a sulphuric acid bath, and was then allowed to cool. The charred mass after being boiled in a small quantity of alcohol, was shaken with a hot strong solution of sodium hydrogen sulphite, filtered from tarry matter, and the dark coloured liquid extracted with successive small quantities of ether, which dissolved a considerable amount of volatile nitrogenous matter soluble in water. On acidifying with sulphuric acid the solution of the bisulphite compound of the quinone, and distilling with steam, the whole of the quinone volatilised within the first few minutes. It was then collected and repeatedly crystallised from alcohol. The yield was less than 5 per cent. of the original a-chloronitrocamphor. A specimen purified in the manner described was dried over sulphuric acid, sublimed, and analysed. 0.2044 gave 0.5406 CO2 and 0·1588 H2O. C=72·1; H = 8·6. The substance crystallised from alcohol in bright yellow, glistening needles or flattened prisms, and melted at 196-198° (Claisen gives 198°). It dissolved readily in hot alcohol, in ether, but only sparingly in hot water, and the hot aqueous solution had a characteristic odour reminiscent of camphor. Although the yellow solutions were not decolorised by sulphurous acid, they were when boiled with sodium hydrogen sulphite, the yellow tint appearing again on boiling with dilute sulphuric acid. As indicated above, the quinone volatilised with ease in steam; it sublimed readily below 100°, and even at the ordinary temperature, the apparently amorphous mass gradually becoming covered with glistening, yellow needles. The above properties are exactly those of the quinone described by Claisen, and, in order to establish their identity, a specimen was made by his method; the two were found to be indistinguishable, and, when mixed, the melting point was not depressed. Under convergent, polarised light, the flattened needles of the two specimens were seen to have their optic axial plane parallel to the large face, and to possess, apparently, equally strong double refraction. The substance obtained from a-chloronitrocamphor when heated with phenylhydrazine in acetic acid solution, yielded a hydrazone which crystallised from alcohol and chloroform in yellow needles melting at 169-171°, the melting point given by Claisen. There can be no doubt, therefore, that camphorquinone is produced from a-chloronitrocamphor by the action of heat, and that the decomposition of the latter substance is, in part, similar to that of the orthobromonitroketonaphthalenes. Chemical Department, City and Guilds of London Central Technical College. XXXIII.-The Action of Lead Thiocyanate on the Chlorocarbonates. Part I. Carboxyethylthicarbimide and its Derivatives. By ROBERT ELLIOT DORAN. AFTER numerous attempts by various chemists to obtain thiocarbimides of the acidic type, their synthesis was first effected by Miquel (Ann. Chem. Phys., 1877, [5], 11, 289), whose method consisted essentially in heating together, under suitable conditions, lead thiocyanate and the corresponding acid chloride; in this way he succeeded in preparing acetyl, butyryl, benzoyl, and salicyl thiocarbimides, two of which, CH, CO NCS and C,H,CONCS, were isolated, and their |