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sence of ammonium thiocyanate increases the yield of the product. NH CMes

Thiomethyluracil, CS<NH·CO- >CH, is very sparingly soluble in

alcohol, ether, and cold water. It crystallises in plates, and begins to decompose at 280°. The silver and copper salts are amorphous. The mercuric salt forms anhydrous, microscopic needles. The potassium salt, CHÂN2OSK + H2O, is insoluble in alcohol, but freely soluble in water. The sodium salt, C,H,N2OSNa + 2H2O, crystallises in prisms, which effloresce on exposure to the atmosphere. The methyl salt melts at 219-220°, but begins to sublime at 120°, forming plates or needle-shaped crystals. The addition of silver nitrate to the ammoniacal solution of this substance precipitates the compound C,H,N,SOAg. The ethyl compound melts at 144-145°.

Ethyl thiomethyluracilacetate is obtained in needle-shaped crystals by the action of ethyl monochloracetate on thiomethyluracil. Thiomethyluracilacetic acid crystallises in needles or plates, and melts at 203-204°. It is very sparingly soluble in cold water, alcohol, and ether.

Thiomethyluracil unites with hydrogen bromide to form an unstable crystalline additive product. Bromine acts on thiomethyluracil suspended in water, eliminating the sulphur and forming dibromoxymethyluracil. By a similar reaction, dichloroxymethyluracil is obtained in transparent plates, soluble in hot water and in warm alcohol. Thiomethyluracil is converted into methyluracil by boiling with freshly precipitated silver or mercuric oxide, and also by the action of ammonia or strong hydrochloric acid at 150°, and of acetic acid at 180°. W. C. W.

On

Nitro-derivatives of Methyluracil. By A. KÖHLER (Annalen, 236, 32-57).—Behrend (Annalen, 229, 32) obtained nitrouracilcarboxylic acid and a compound, CH2N,Os, by the action of strong nitric acid on methyluracil. Nitrouracilcarboxylic acid, C,H,NO, + 2H2O, crystallises in rhombic prisms; a:b: c = 0·323:1:1·081. boiling the aqueous solution, carbonic anhydride is evolved and nitrouracil, C,H,NO,, is formed. Ethyl nitrouracilcarboxylate, prepared by saturating the alcoholic solution of the acid with hydrogen chloride, crystallises in monoclinic prisms. It is less soluble in alcohol and water than the free acid, and it does not split up on boiling with water. The salt melts at about 250° with partial decomposition. The constitution of this substance may be represented by the formula CO- NH >C.COOET. CO.C(NO2)=

NH<

Amidouracilcarboxylic acid, C,H,N,O,, is formed by the action of tin and hydrochloric acid on the nitro-acid, but a better yield is obtained by the reduction of the ethyl salt. The product, consisting of a mixture of the ethyl salts of amidouracilcarboxylic and hydroxyuracilcarboxylic acids, is saponified by boiling with an aqueons solution of potassium hydroxide. Amidouracilcarboxylic acid is deposited from its aqueous solution in needles. Between 150° and 160°, it splits up into carbonic anhydride and amidouracil. The potassium salt, C¿H ̧Ñ ̧Ó ̧K + H2O, crystallises in prisms; the barium,

copper, and mercury salts are amorphous. The sparingly soluble lead and silver salts are crystalline. The ethyl salt is insoluble in alcohol and sparingly soluble in water. It melts at 260° with partial decomposition.

A good yield of nitrouracil is obtained by adding 5 c.c. of strong sulphuric acid to 4 grams of methyluracil suspended in 10 c.c. of fuming nitric acid. The yield of the sparingly soluble compound, CH2NO, which is obtained as a bye-product by the action of nitric acid on methyluracil, is increased by warming the mixture as soon as the reaction ceases.

This compound unites with bases to form salts. CHNO, NH ̧ + H2O crystallises in yellow glistening needles; C,HN,O,K + 11⁄2Н20, red needles, sparingly soluble in water; the solution decomposes on boiling. The barium salt, (C,HN,O),Вa + 4H2O, forms prismatic needles, freely soluble in water. On reduction with tin and hydrochloric acid, the amido-compound, C,H,NO, + H2O, is obtained in slender needles, sparingly soluble in water. After evaporation with hydrochloric acid, the residue yields the murexide reaction.

W. C. W.

New Mode of Formation of Dibromo- and Dichloro-barbituric Acids. By R. BEHREND (Annalen, 236, 57-68).-The most convenient method of preparing bromomethyluracil (Abstr., 1886, 338) is to convert methyluracil into dibromoxymethyluracil by the action of bromine-water (Annalen, 229, 18), and to decompose the product by boiling in alcohol. Dichloroxymethyluracil resembles the corresponding bromo-derivative in its properties and in its mode of preparation. It crystallises in triclinic plates, and is not decomposed by boiling with alcohol. It is decomposed by alcohol or water at 150°, forming a sparingly soluble compound, and is converted into monochloromethyluracil by the action of stannous chloride and hydrochloric acid. Chloromethyluracil is insoluble in ether, sparingly soluble in water and alcohol. It crystallises in needles.

Dibromoxymethyluracil is oxidised to dibromobarbituric acid by fuming nitric acid. This is identical with the dibromobarbituric acid described by Baeyer (Annalen, 130, 130). Hot fuming nitric acid converts dichloroxymethyluracil into dichlorobarbituric acid, CH2C12N2O. This substance crystallises in rhombic prisms or plates, a: b: c = 0.7766:1:0-8929. The crystals are isomorphous with those of dibromobarbituric acid, and are much more soluble in alcohol, ether, and water. A small quantity of barbituric acid is formed in the preparation of dichlorobarbituric acid by this process.

W. C. W.

Relation of the so-called a-Thiophenic Acid to the Normal Thiophencarboxylic Acids. By V. MEYER (Annalen, 236, 200— 224). In former communications (Abstr., 1885, 1207; 1886, 227, 534), the author has pointed out that the derivatives of a- and B-thiophenic acids (melting at 118° and at 126 5° respectively), are identical in crystalline form, solubility, and melting point, but that on decomposition the a-derivatives yield the a-acid, and the B-derivatives the B-acid. The so-called a-acid is really a mixture of the ß- and y-acids, which cannot be separated by recrystallisation. It is formed on

oxidising a mixture of B- and y-thiotolens, but is not obtained by mixing together the ready-formed ẞ- and y-acids. In the thiophengroup the tendency for the isomeric compounds to crystallise together is much stronger than in any other series. W. C. W.

Halogen Carriers. By C. WILLGERODT (J. pr. Chem. [2], 34, 264-292).—An account of experiments on the effective value of various elements and their compounds in the chlorination of benzene (compare Abstr., 1885, 1034). Two cases occur on the passage of chlorine into benzene in presence of these foreign substances, namely, either the formation of benzene hexachloride attended by a considerable gain in weight of the benzene and practically no evolution of hydrogen chloride, or the displacement of hydrogen by chlorine with corresponding evolution of hydrogen chloride. The details of the various experiments are given in full. To the substances inducing the first reaction belong aluminium hydroxide and sulphate; those inducing the latter reaction are again separable into those elements the presence of which induces the production of mono- or di-substitutionderivatives, and those forming a chloride of the formula XCl, or (XCl2), which lead to the production of tetra- or penta-substitutionderivatives. The function of these is conditioned by the atomic mobility of the chlorine-atoms in its compound, and in fact to the affinity of some kind or another of the inorganic chloride for the carbon compound. Adopting the periodic system of classification, the members of the first two groups are inactive, those of the second, fifth, seventh, and eighth groups are eminently active, and those of the fourth are, with the exception of tin, inactive.

The experiments of Lothar Meyer, Friedel and Crafts, and others on the chlorination of carbon compounds by means of such substances as aluminium or ferric chloride, seem to indicate that at first a hydrogen-atom of the hydrocarbon is displaced by the grouping M.Cl, with separation of hydrogen chloride, and to this compound a molecule of chlorine adds itself on and finally takes the place of the hydrogen. The compounds Al2Cl6,6C&He (or 6C,H) obtained by Gustavson, the author regards as combinations of a molecule of metallic chloride with one of the hydrocarbon, the remaining five molecules functioning in like manner to water of crystallisation. V. H. V.

Preparation of Organic Fluorides. By O. WALLACH (Annalen, 235, 255-271).-Fluorobenzene, C,H,Fl, can easily Be prepared by pouring 20-30 c.c. of strong hydrofluoric acid into a flask containing 10 grams of benzene diazopiperidide. The flask is connected with a receiver by means of a spiral condenser surrounded by a freezing mixture. A tube passes through the doubly perforated cork which closes the receiver, and dips into mercury. On gently warming the flask, the reaction commences and the fluorobenzene collects in the receiver. Fluorotoluene is prepared from toluene paradiazopiperidide. As it is much easier to condense than fluorobenzene, the apparatus may be simplified by omitting the tube dipping under mercury. Fluorotoluene resembles benzonitrile in odour. It is oxidised by chromic acid, yielding fluorobenzoic acid.

Nitrobenzeneparadiazopiperidide forms golden, needle-shaped crystals. It melts at 96-97°, and dissolves freely in ether and warm alcohol. It is decomposed by hydrofluoric acid, yielding parafluoronitrobenzene. This compound is also formed by nitrating fluorobenzene. It melts at 21-22° and boils at 204-206°.

Acetamidobenzene metadiazopiperidide, C.H,(NHAC)N: N2CH 10, is deposited from weak alcohol in thick prisms which melt at 100— 101°. It is decomposed by hydrofluoric acid, yielding metafluoraniline; an oily liquid resembling aniline. Parafluoraniline is formed by reducing an alcoholic solution of parafluoronitrobenzene with stannous chloride and hydrochloric acid. The nitrate, hydrochloride, and sulphate crystallise well. Acetic anhydride converts parafluoraniline into acetofluoranilide. This compound is sparingly soluble in water, but dissolves readily in alcohol.

The replacement of hydrogen by fluorine increases the sp. gr., but has very slight effect on the boiling points of the compounds.

[blocks in formation]

Fluorobenzenesulphonic acid and fluorodiphenyl, when added to an alkaline solution of piperidine, form the compounds

NaSO, CH, N2 C2NH10

and C ̧NH10 N2 C ̧H ̧•C‚H ̧•N2°C2NH10 respectively.

2

2

W. C. W.

Reaction of Potassium Cyanide with Orthonitrobenzylic Chloride. By E. BAMBERGER (Ber., 19, 2635-2642).—In the reac tion between potassium cyanide and orthonitrobenzylic chloride there are formed, besides orthonitrobenzyl cyanide, an orthodinitrocyanodibenzyl and substances of the composition C2HNO, and C15H,NO3, the constitution of which is uncertain.

Orthonitrobenzyl cyanide, NO2 CH, CH2 CN, previously described by Salkowski, crystallises in pale-yellow prisms which melt at 82.5°; its solutions give a blue-violet coloration on addition of a trace of alkali ; the dye formed is, however, unstable.

Orthodinitrocyanodibenzyl, NO, CH, CH(CN) CH2 CH, NO2, crystallises in snow-white prisms, melts at 110.5° and is soluble in benzene, alcohol, and acetic acid. This substance is also obtained directly from orthonitrobenzyl chloride and the corresponding cyanide. It is very stable towards acids; when heated with alkalis and the product heated with mineral acids, a compound, C15H,N3O3, separates out in voluminous, yellow flocculæ, which can be crystallised from alcohol in silky leaflets melting at 235-238°. The same substance is also a subsidiary product in the above reaction.

The compound C2H1NO, mentioned above, crystallises in thick glistening prisms which melt at 190.5°; it is sparingly soluble in alcohol, readily in acetic acid; it behaves towards acids and alkalis as a perfectly indifferent substance. V. H. V.

Oxidation of Nitromesitylene, By W. H. EMERSON (Amer. Chem. J., 8, 268-271).-Schmitz has pointed out that as paranitromesitylenic acid is produced during the preparation of mononitromesitylene, it is probable that the first-named substance is produced by the oxidation of the last-named, and therefore here as in other cases, except with mesitylene sulphonamide, the presence of the nitro-group protects those hydrocarbon side-chains that occupy the ortho-position relatively to the negative nitro-group. This oxidation has before been attempted but without success; by dissolving both the substance and the chromic acid in glacial acetic acid, however, the para nitromesitylenic acid was actually obtained and recognised by its properties and by those of the corresponding amido-acid. H. B.

15

Intramolecular Changes in the Propyl-group of the Cumene Series. By O. WIDMAN (Ber., 19, 2769-2780).-Propylhydrocarbostyril, Č12HINO, is obtained by treating a solution of orthamidocumenylacrylic acid (Abstr., 1886, 465) in soda with an excess of sodium amalgam. Acetic acid is then added, which precipitates a yellow substance melting at 80°; this changes in a short time to propylhydrocarbostyril melting at 134°. The latter crystallises in well-formed rhombic prisms, a b c = 0·87978: 1: 1·64451; B = 1-620435, and is very readily soluble in alcohol and benzene. The compound is also obtained by reducing orthamidoparapropylcinnamic acid (Abstr., 1886, 464). In the latter reaction, the isopropyl-group must have undergone an intermolecular change; propylhydrocarbostyril is therefore a normal compound of the formula

CH2 CH2

CH,Me•CH,CH<NH CO.

2

Cumenylpropionic acid (Perkin, this Journal, 1877, i, 400) is best prepared by boiling pure cumeny lacrylic acid for 45 minutes with 20 times its weight of hydriodic acid (sp. gr. 17) and an equal weight of red phosphorus. The product is filtered, washed with water, and dissolved in ammonia; it is precipitated with acid, pressed, and dried. It melts sharply at 75.5° (not 70°). When gradually treated with fuming nitric acid (10 parts) at -5° to 0°, and the product poured into water, a white crystalline nitro-acid is precipitated; it crystallises from 50 per cent. acetic acid in well-formed plates melting at 99°. When reduced, it yields propylhydrocarbostyril. When cumenylpropionic acid is oxidised by potassium permanganate, it is converted into orthonitrohydroxyisopropylbenzoic acid (Abstr., 1886, 466).

The above experiments show that a conversion of isopropyl into normal propyl occurs in the successive conversion of cumenylacrylic acid into cumenylpropionic acid, orthonitrocumenylpropionic acid, and propylhydrocarbostyril. The same molecular change also takes place when cumenylacrylic acid is converted successively into

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