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sition at 140-150° under a pressure of 20 mm. It is not identical with the preceding compound, and may have the constitution

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The action of bromine on ordinary dichloracetone yields a liquid which boils at 120° under a pressure of 25 mm., and does not solidify at a low temperature. It forms a tetrahydrate which crystallises in hexagonal tables with a very disagreeable odour; these readily lose their water. Barbaglia's dichloracetone boiling at 170° yields the same derivative with bromine, and is therefore a polymeride of ordinary dichloracetone. Dibromodichloracetone reacts energetically with ammonia, but no chlorobromoform is produced, and hence the compound must have the constitution CHC CO-CHBг. With mercuric chloride, it yields a tetrachloracetone which does not contain the group CCI,.

When trichloracetone is treated with bromine at 100°, it yields a trichlorobromacetone, which boils at 107° under a pressure of 25 mm., and at 190° under the ordinary pressure. It is very hygroscopic, and forms a tetrahydrate which crystallises in hexagonal tables melting at 48°. With ammonia, it yields chloroform and bromacetamide, and therefore must have the constitution CCl, CO-CH2Br.

Tetrabromacetone forms a tetrahydrate, which, although unstable, crystallises readily. With ammonia, it yields bromoform and bromacetamide.

All the chlorobromacetones described are tetra-substitution-derivatives. Starting from tetrachloracetone, each substitution of bromine for chlorine produces a rise of about 10° in the boiling point. There is also a gradual increase in the specific gravity.

Action of Ammonia and Amines on Chloracetones.-The action of orthotoluidine on hexachloracetone yields orthocresyltrichloracetamide, CH,Me NH C2Cl2O, which crystallises in large needles only slightly soluble in cold alcohol. It melts at 66–67°, readily remains in superfusion, and volatilises at 215°. Paratoluidine yields the corresponding para-derivative, which crystallises in very short rectangular prisms, melting at 79-80°, and volatilising with partial decomposition at 185°. It is only slightly soluble in cold alcohol.

With diethylamine, hexachloracetone yields diethyltrichloracetamide, which is very soluble in alcohol, and crystallises in prisms which melt at 90° and volatilise almost immediately with partial decomposition. With trimethylamine, dimethyltrichloracetamide is formed; this is very soluble in boiling alcohol, and crystallises in radiating needles which melt at 104°, and sublime at 195°. With dimethylaniline, the reaction takes place only on warming, and the product is a mixture of a violet colouring matter, soluble in boiling water but almost insoluble in ether, and very soluble in chloroform, with another badly defined colouring matter. Allylamine yields allyltri chloracetamide, soluble in alcohol and in chloroform, and crystallising in large tables which melt at 45° and volatilise without decomposition at 190°. With hexachloracetone and pentachloracetone respectively, ethylenediamine yields the two derivatives, C2H ̧: Ñ‚Í ̧·¤‚Ù‚Ø

and C2H, N2HC2HCl2O. The first is soluble in alcohol, and crystallises in elongated rhomboidal plates which melt at 200° and sublime at the same temperature. The second is soluble in warm alcohol, and

very soluble in ether. It crystallises from alcohol in elongated parallelograms, and from ether in fan-shaped plates.

When one molecular proportion of urea is heated at 150° with two molecular proportions of hexachloracetone, the amide

CO: N2H2(C2Cl3O) 29

is readily obtained. It crystallises from its alcoholic solution in yellowish, hexagonal plates. C. H. B.

Chlorinated Methyl Formates. By W. HENTSCHEL (J. pr. Chem. [2], 36, 209-215).-Continuing his previous work (this vol., p. 1027) the author has repeated Cahours' investigation (Ann. Chim. Phys. [3], 19, 342) on the chlorination of methyl formate, but with totally different results.

The chlorination takes place very slowly in the dark, very rapidly in bright daylight, and care must be taken to prevent an accum lation of the two reacting substances, or violent explosions occur. The author obtained the trichloromethyl chloroformate, C2ClO2, previously described by him (loc. cit.), but could obtain no such stable compound, C2ClO2, boiling at 180-185°, as is described by Cahours, and usually given in text-books. He believes that such a compound does not exist, and that Cahours must have been mistaken in his results.

L. T. T. Action of Sodium on Ethyl Salts of the Higher Fatty Acids. By O. WOHLBRÜCK (Ber., 20, 2332-2340; comp. this vol., p. 717).-Ethyl dimethylisobutyrylacetate, CHMe, CH·CO CMe2 COOEt, is obtained by adding 30 grams of sodium to 100 grams of ethyl isobutyrate diluted with an equal weight of absolute ether, the whole being kept cool. Afterwards it is heated in a water-bath for some hours. The product is poured into water, and the oil so obtained is treated with dilute aqueous soda, dried and distilled. It is a lemonyellow liquid of a strong aromatic odour, boiling at 186-189° under 716 mm. pressure.

a-Dimethyl-B-hydroxyisocaproic acid,

CHMe, CH-CH(OH) CMe2 COOH,

is contained as sodium salt in the soda used in purifying the above ethyl salt, and crystallises in prisms melting at 108°. It is soluble in water, readily in ether. The barium salt with 3 mols. H2O forms readily soluble, microscopic plates; the silver salt blackens when exposed to light, and gives a mirror when heated in water. The acid is also formed by the reduction with sodium of ethyl dimethylisobutyrylacetate diluted with alcohol.

Ethyl isopropylisovalerylacetate,

CHMe CH, CO-CH(CHMe2) COOEt,

is prepared by the action of sodium (38 grams) on ethyl isovalerate (100 grams) diluted with dry ether. The product is purified in a manuer similar to ethyl dimethylisobutyrylacetate. It is a bright

yellow oil boiling at 204-207 under 722° mm. pressure. When treated with bromine, and the product decomposed by an alkali, an acid melting at 185-187° (probably C10H18O3) is obtained.

a-Isopropyl-B-isobutylhydracrylic acid,

CHMe CH, CH(OH)·CH(CHMe2)·COOH,

is contained in the aqueous alkaline extract from ethyl isopropylisovalerylacetate. It is an oil which solidifies after some days to long, slender needles of a silky lustre. It melts at 120°, and dissolves readily in alcohol, ether, and hot water. When heated above its melting point, it sublimes in lustrous needles. The barium salt crystallises in hard, colourless prisms. The acid can also be obtained by reducing ethyl isopropylisovalerylacetate with sodium.

N. H. M.

Transformation of Fumaric and Maleïc Acids into Aspartic Acid and Asparagine. By G. KOERNER and A. MENOZZi (Gazzetta, 17, 226–231).—The authors have shown that paraffinoïd amido-acids can be converted into olefinoïd acids by the introduction of the methylgroup into the amido-residue, and subsequent removal of the elements of the amine. A case of the converse change is here investigated, in that it is shown that ethyl fumarate, when heated with alcoholic ammonia in sealed tubes, yields an oil, ethyl aspartate, and a substance of the composition CH,N2O2. The ethyl aspartate is a colourless oil, which boils at 150-154° under a pressure of 25 mm., but is decomposed when distilled at the ordinary pressure. The compound CH.NO, crystallises in glistening leaflets melting at about 250° with decomposition; it may be regarded probably as the imide of aspartic acid; on protracted heating with alcoholic ammonia, it is converted into asparagine. The above-mentioned oil when treated with aqueous ammonia yields asparagine in abundance, the crystals formed showing hemihedric modifications.

In like manner, ethyl maleate yields identical products, and practically in the same proportion. V. H. V.

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Oxidising Action of Alloxan. By G. PELLIZZARI (Gazzetta, 17, 254 -259). When a concentrated aqueous solution of alloxan is added to phenylhydrazine hydrochloride in presence of sodium acetate, nitrogen and benzene vapour are evolved, and alloxantin is formed thus: 2C,H2N2O, + NHPh⋅NH, CH,N,O,+ CH2+ N2+ H2O. It is supposed that in the first phase of the reaction two atoms of hydrogen are eliminated in the form of water, with formation of a hypothetical diazobenzene, which decomposes into benzene and nitrogen. If this view were correct, then hydrazobenzene under similar conditions should yield azobenzene, a result confirmed by experiment.

An analogous result was obtained with indigo-white, the alloxan being reduced to alloxantin, whilst simultaneously the white is oxidised to indigo-blue, thus: 2C,H2N2O ̧ + C1H12N2O2 = C2H ̧Ñ‚O; + C16H10N2O2 + H2O.

Ceresole (Abstr., 1883, 913) has shown that hydroxylamine hydrochloride acts on alloxan in a manner similar to the usual reaction with ketones, leading to the formation of violuric acid. In the p-per,

this result is confirmed, and the identity of the product formed with violuric acid is established by crystallographic measurements.

V. H. V.

1:3 Methylphenylthiophen and 1:2 Thioxen. By C. PAAL and A. PUSCHEL (Ber., 20, 2557-2560).-1: 3 Methylphenylthiophen, C,SH,MePh, is obtained when phenyllevulinic acid, or preferably its sodium salt, is heated with phosphorus trisulphide or pentasulphide; the sodium salt must contain water, otherwise carbonisation is the sole result. It crystallises in large, nacreous laminæ, melts at 72-73°, distils without decomposition, and is readily soluble in alcohol, benzene, &c. It is less volatile with steam than its isomerides, has an odour resembling that of diphenyl, and gives the indophenine reaction, but does not show Laubenheimer's reaction distinctly. The tetrabromoderivative, C1SH,Br, formed by the action of methylphenylthiophen on an excess of bromine in the cold, crystallises in slender needles or scales, melts at 136-137°, and is readily soluble in ether, benzene, and light petroleum, less so in alcohol and acetic acid.

1: 2 Thioxen, C,SH,Me, is prepared by distilling 3-methyllevulinic acid with phosphorus trisulphide, and washing the distillate with icecold, dilute, aqueous soda. It is a colourless liquid, which boils at 134 -138°, and shows the indophenine and Laubenheimer reactions. The alkaline solution employed for washing the distillate contains 1: 2: 4 thioxenol.

W. P. W.

Action of Methyl Chloride on Orthodichlorobenzene in Presence of Aluminium Chloride. By C. FRIEDEL and J. M. CRAFTS (Ann. Chim. Phys. [6], 10, 411-424).-The action of methyl chloride on dibromortho-xylene in presence of aluminium chloride is very complicated, and no definite products were obtained.

Orthodichlorobenzene, prepared by Istrati, was purified by crystallising out the less fusible para-derivative, and dissolving the orthodichlorobenzene in a mixture of equal vols. of ordinary sulphuric acid and the fuming acid, which leaves the greater part of the still admixed para-derivative undissolved. The sulphonic acid thus obtained was recrystallised and decomposed by heating in a retort into which a current of steam was passed. Some paradichlorobenzene distils over at 100°, and the ortho-derivative passes over in an almost pure condition at about 200°. It boils at 178°; sp. gr. at 0° 1.3254. During distillation, crystals of the sulphone (CH,Cl2),SO, condense in the upper part of the condenser; they melt at 173°, and boil at 360° with partial decomposition.

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The orthodichlorbenzene was mixed with 20 per cent. of aluminium chloride, heated on a water-bath, and treated with a current of dry methyl chloride for about 10 hours. The chief products are hexamethylbenzene and trichloromesitylene.

Hexamethylbenzene thus obtained crystallises in long needles which melt at 164° and boil at 264°. With an excess of picric acid, it forms a compound containing the two substances in equal molecular proportions, and which crystallises in golden-yellow lamella melting at 168-169°.

Trichloromesitylene contains more chlorine than the original com

pound, although some of the latter always remains unaltered. Its formation is not due to the presence of any trichlorobenzene. It crystallises from alcohol in slender needles, which melt at 205° and boil at 280° without decomposition. When heated in sealed tubes with 16 times its weight of hydriodic acid of sp. gr. 19, in the vapour of diphenylmethane, it yields mesitylene. Under the same conditions, xamethylbenzene yields mesitylene and methane.

The formation of hexamethylbenzene is doubtless due to the reducing action which has been observed in similar reactions. Probably the organo-metallic compound is produced from the dichlorobenzene, with displacement of chlorine and not of hydrogen, and this chlorine produces the trichloromesitylene. Analogous phenomena have been observed by L. Roux in the action of aluminium chloride on the haloïd derivatives of naphthalene.

In addition to hexamethylbenzene, a small quantity of a compound which seems to be a chloromethyl-derivative of diphenyl, is formed. Aluminium chloride alone has no action on orthodichlorobenzene at

160°.

C. H. B.

Action of Methylene Chloride on Methylbenzenes in Presence of Aluminium Chloride. By C. FRIEDEL and J. M. CRAFTS (Ann. Chim. Phys. [6], 11, 263-277).-Benzene yields toluene, diphenylmethane melting at 25° and boiling at 260-265°, and anthracene. The absence of hydranthracene is due to its reduction to anthracene and methyl chloride by the action of the methylene chloride, the methyl chloride then producing the toluene. The relative quantities of diphenylmethane and anthracene obtained depend on the proportions of methylene chloride and benzene.

Toluene yields a mixture of meta- and para-xylene boiling at 130— 150°, ditolylmethane boiling at 280-290°, and dimethylanthracene melting at 231–232°.

Metaxylene, in addition to liquid products, yields tetramethylanthracene melting at 162-163°; this unites with picric acid in equal molecular proportions to form a deep red compound crystallising in stellate groups. Oxidised with chromic acid in presence of acetic acid, it yields yellowish-white prisms which melt at 206°, and have the composition C8H16O2. From its mode of formation this tetramethylanthracene must have the constitution 1' 3': 1: 3 or 1': 3′ : 2 : 4.

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Pseudocumene yields durene and solid products, which melt respectively at about 165°, 220°, and 290°. The first is a small quantity of tetramethylanthracene identical with that obtained from metaxylene. The second consists of hexamethylanthracene, which from its mode of formation must have the constitution 1': 2' 4' 1: 2: 4 or 1' : 3' : 4' 1: 2: 4. If it is mixed in alcoholic solution with picric acid, the two substances unite in equal molecular proportions, and the compound separates in small, golden-brown needles which melt at about 203°. The hydrocarbon dissolves in sulphuric acid, forming a red solution, which becomes colourless as the acid absorbs moisture from the air. The third product might be expected to be a hepta- or octamethylanthracene. It has the composition CiH18, forms no compound

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