yields the 4: 5- and 4: 8-dinitro-derivatives, 2: 4-dinitro-1-methylnaphthalene being prepared from 1-chloro-2: 4-dinitronaphthalene through reaction with ethyl sodiomalonate. The methyl-hydrogen atoms of 2: 4-dinitro-1-methylnaphthalene react readily with aromatic aldehydes and with nitrosodimethylaniline, their reactivity being intermediate between that of 24-dinitrotoluene and 2:4: 6-trinitrotoluene. Ethyl oxalate readily yields a condensation product, insoluble in alkali, which is probably the corresponding tetranitrodinaphthylethane.

1-Chloro-2: 4-dinitronaphthalene, obtained by Ullmann and Bruck's method (A., 1909, i, 21), using dimethylaniline in place of diethylaniline, condenses with ethyl acetoacetate in the presence of sodium, yielding ethyl 2: 4-dinitro-a-naphthylacetoacetate, m. p. 131°, which on heating with acetic and dilute sulphuric acids gives 2: 4-dinitro-a-naphthylmethyl methyl ketone, m. p. 161°. Similarly ethyl malonate condenses with 1-chloro-2: 4-dinitronaphthalene, yielding ethyl 2:4dinitro-1-naphthylmalonate, m. p. 107-108°, together with a small quantity of ethyl 2: 4-dinitro-1-naphthylacetate, m. p. 128°. On heating with acetic anhydride containing a little sulphuric acid, the malonate is converted into 2 : 4-dinitro-a-naphthylacetic acid, m. p. 211°, falling in 8 days to 161° and then rising in 3 months to 171°, from which 2: 4-dinitro-1-methylnaphthalene, m. p. 161°, is obtained on treatment with cold pyridine. With p-nitrosodimethylaniline in a mixture of acetone and alcohol 2: 4-dinitro-1-methylnaphthalene yields the product,

C10H5(NO2)2CH.N⚫CH1NMe2, m. p. 168°, from which on treatment with concentrated hydrochloric acid 2 : 4-dinitro-1-naphthaldehyde, m. p. 156°, is obtained. R. BRIGHTMAN.

The imino-residue. K. F. SCHMIDT (Ber., 1925, 58, [B], 2413-2415; cf. A., 1924, i, 721). A reply to Oliveri-Mandalà (A., 1925, ii, 815). H. WREN.

Preparation of acetoacetanilide. H. PFEIFFER (J. pr. Chem., 1925, [ii], 111, 240-241; cf. Knorr, A., 1887, 159; Roos, Ber., 1888, 21, 624; Knorr and Reuter, A., 1894, i, 371).-The best yield (50%) of acetoacetanilide is obtained by heating together aniline (1 mol.) and ethyl acetoacetate (1 mol.) for 15 min. in an open flask at 160°. The whole sets, when cooled in a freezing mixture, to a crystalline mass, which, after washing with a mixture of benzene and light petroleum, has m. p. 86°. . A further small quantity, equally pure, is obtained from the motherliquors on keeping. C. HOLLINS.

Ready method for the preparation of o-nitroaniline in the laboratory. E. SAKELLARIOS and D. JATRIDES (Ber., 1925, 58, [B], 2286-2288). Sulphanilic acid is converted into potassium acetylsulphanilate by the addition of acetic anhydride in slight excess to an aqueous solution of potassium sulphanilate in such a manner that the temperature is maintained at 65-70°. The finely divided salt is dissolved in concentrated sulphuric acid and nitrated with a mixture of nitric acid (85%) and sulphuric acid at 5°. The acetyl and sulphonyl groups are removed from the resultant potassium o-nitroacetylsulphanilate by boiling sulphuric acid

(67%), whereby o-nitroaniline is obtained in 80% yield. H. WREN.

Action of cyanamide on picryl chloride. M. GIUA (Gazzetta, 1925, 55, 662-665).-The action of excess of 12% aqueous cyanamide solution on alcoholic picryl chloride solution yields: (1) 2:4:6trinitrophenylcarbamide (picrylcarbamide), m. p. 201-203° (decomp.); Kniphorst (A., 1925, i, 905) gave m. p. 196-199°; (2) "dipicrylguanylcarbamide,' CH2(NO2)3 N(CO-NH2) C(NH2) N°C ̧H2(NO2)3, dipicryldicyanodiamidine,'

66

or

CH2(NO2)3 N(CO⚫NH2) C(NH) NH•C ̧H2(NO2)3, m. p. 254-255° (decomp.), which can be regarded as formed by the combination of 1 mol. of picrylcyanamide with 1 mol. of picrylcarbamide. T. H. POPE.

Indanyl bases. C. COURTOT and A. DONDELINGER (Ann. Chim., 1925, [x], 4, 222-292).-A detailed account of the preparation of substituted indanylamines previously described (A., 1923, i, 1090; 1924, i, 279). The following, however, do not seem to have been previously described: di-indanylmethylamine, m. p. 92-93°; diphenylindanylamine, m. p. 85-86°; m-nitrophenylindanylamine, m. p. 127-128° and 137-138° (the two m. p. are probably those of two crystalline forms); p-nitrophenylindanylamine, m. p. 126-127°; a-naphthylindanylamine (which could not be obtained in a pure condition); B-naphthylindanylamine, m. p. 169-170°. The hydrochlorides of all these bases were prepared. J. W. BAKER.

Indanyl bases. C. COURTOT and A. DONDELINGER (Ann. Chim., 1925, [x], 4, 293-369).-A detailed account of the optical data, absorption spectra, measurements of the affinity constants and degree of dissociation of the hydrochlorides of the indanyl bases (cf. preceding abstract) previously described (cf. A., 1925, ii, 274; Bourgeaud and Dondelinger, ibid., 117) is given. The hydrogen oxalates of the bases were also prepared and examined. The action of the hydrogen halides on indene has been. investigated. The addition of hydrogen chloride has been investigated previously (cf. Weissgerber, A., 1911, i, 623); hydrogen bromide and iodide give a quantitative yield of 1-bromo- and 1-iodo-hydrindene, respectively, which cannot be purified, since they readily lose hydrogen halide and yield a polymeride of indene, but they may be used immediately after preparation as synthetic agents, condensing with o-toluidine to yield o-tolylindanylamine in 74% yield. Hydrofluoric acid behaves like sulphuric acid, causing only polymerisation of the indene. J. W. BAKER.

Formation of cyclohexyl ether. V. N. IPATIEV and J. ORLOV (Compt. rend., 1925, 181, 793-795; cf. A., 1908, i, 342; 1912, i, 544; 1924, i, 725).— The material of high b. p. obtained from the hydrogenation products of phenol and diphenyl ether appears to be cyclohexylcyclohexanol, since when heated with aluminium oxide and copper oxide in the presence of hydrogen a mixture of cyclohexene and dicyclohexyl, b. p. 237-238-5°, d2° 0-8835, separated by treatment with sulphuric and nitric acids, is obtained. Dicyclohexyl of slightly different properties, possibly a stereo

isomeride, b. p. 236–237.5°, d20 0.8919, is obtained by treatment of diphenylene oxide with hydrogen in the presence of nickel oxide and cyclohexane. L. F. HEWITT.

Reduction of organic compounds containing oxygen by active carbon. G. STADNIKOV, N. GAVRILOV, and A. WINOGRADOV (Ber., 1925, 58, [B], 2428-2429).-Reduction of cresols to toluene, carbon monoxide, and carbon dioxide is effected by carbon deposited on finely divided iron at 430°. The catalyst is prepared by soaking asbestos in ferric nitrate solution free from chloride and treating the drained product with 10% ammonia. It is reduced by hydrogen at 460-470° and subsequently treated with cresol at 480-490°, whereby the latter substance decomposes into hydrogen, carbon monoxide, and carbon which is deposited on the iron. H. WREN.

and

Condensation products products of dextrose p-phenetidine. M. AMADORI (Atti R. Accad. Lincei, 1925, [vi], 2, 337-342).-Two different products have been obtained by the interaction of equimolecular quantities of anhydrous dextrose and p-phenetidine. When the reaction occurs in the cold, or with brief boiling, a compound (m. p. 118°) is obtained, similar to that described by Irvine (J.C.S., 1909, 95, 1545), but without water of crystallisation. When the reactants are heated together in the dry state at 50-80°, subsequent brief extraction with boiling alcohol results in the isolation of a product of m. p. 155°, which is probably that described by Claus and Ree (Chem.-Ztg., 1898, 22, 545). The physical and chemical properties of these products are described. Both have the same empirical formula, C14H21OGN. F. G. TRYHORN.

Oxidation-reduction. VII. Dichloro-substitution products of phenol-indophenol. H. D. GIBBS, B. COHEN, and R. K. CANNAN (U.S. Pub. Health Repts., 1925, 40, 649-663; cf. A., 1925, ii, 1164). An investigation (including preparation and analysis) of the indo-2: 6-dichlorophenols of phenol, o-cresol, m-cresol, o-chlorophenol, and Schäffer's salt, and the leuco-derivatives of phenol- and m-cresolindo-2: 6-dichlorophenols. The oxidation-reduction potentials in buffer solutions from på 3 to р 13 are in agreement with the formula already developed. The following compounds are selected for indicators of oxidation-reduction in biological systems at pH 7 and 0.001M concentration: m-bromophenol-indophenol, o-chlorophenol-indophenol, phenol-indo-2: 6dichlorophenol, o-cresol-indo-2: 6-dichlorophenol, and "a-naphthol-2-sulphonate-dichlorophenol."

CHEMICAL ABSTRACTS.

Guaiacol derivatives. L. WINKELBLECK (J. Amer. Pharm. Assoc., 1924, 13, 619-622).-The phenylurethane, m. p. 146°, and a-naphthylurethane, m. p. 116-117°, of guaiacol are described; guaiacylacetophenone [o-anisyl acetate ?] has m. p. 104° (phenylhydrazone, m. p. 106-108°; semicarbazone, m. p. 142-147°). CHEMICAL ABSTRACTS.

Relation between chemical constitution and pungency in acid amides. E. C. S. JONES and F. L. PYMAN (J.C.S., 1925, 127, 2588-2598).—By varying both the acyl- and the amido-residues the following acid amides have been prepared and their pungencies compared with that of n-nonovanillylamide=100; x-isopropyl-n-hexovanillylamide, m. p. 125° (pungency about 5); phenylacetovanillylamide, m. p. 112° (non-pungent); B-phenylpropiovanillylamide, m. p. 83° (pungency 40); y-phenyl-n-butyroand 8-phenyl-n-valero-vanillylamides, m. p. 93-95° and 67°, respectively (both slightly>40). The pungencies of chloroacetovanillylamide, m. p. 119–122°, dichloroacetovanillylamide, m. p. 139-143°, trichloroacetovanillylamide, m. p. 76-79°, bromoacetovanillylamide, m. p. 95°, and iodoacetovanillylamide, m. p. 114°, are all about 3; thus the shape rather than the weight of the side chain is the important factor. Where no phenolic hydroxyl group is present in the molecule, as in n-nono-3: 4-methylenedioxybenzylamide, m. p. 92°, and n-nono-4-methoxybenzylamide, m. p. 103°, no pungency was observed, whilst n-nono-4-hydroxybenzylamide, m. p. 92°, n-nono-3: 4-dihydroxybenzylamide, m. p. 78°, and A-undeceno-3: 4-dihydroxybenzylamide, m. p. 70-74°, had pungencies of 10, 25, and 50, respectively. B. W. ANDERSON.

Absorption spectra of benzaurin. W. R. ORNDORFF, R. C. GIBBS, and S. A. MCNULTY (J. Amer. Chem. Soc., 1925, 47, 2767-2777).—Absorption spectra of solutions of benzaurin in neutral alcohol, alcoholic hydrochloric acid, 93% sulphuric acid, alcoholic alkali, and 33% aqueous alkali, and of pp'-dihydroxytriphenylmethane in neutral alcohol, are recorded. The continuous spectrum obtained by the discharge from a Tesla coil between electrodes immersed in water, which extends from the green of the visible spectrum to well into the ultra-violet, was used as the source of illumination, calibration being obtained by the use of line spectra from a spark in air between electrodes of suitable metals. Pure benzaurin, orange-red crystals, forms a yellowishorange solution in absolute ethyl alcohol, the colour of which fades on keeping to a light yellow, due to a weakening of an absorption band at frequency 2300 to about 1/18 of its original strength in 10 days. When the faded solution is heated, the orange tint is temporarily restored. The presence of bands at 2033 and 2714 could not be confirmed (cf. Formánek and Grandmougin, "Unters. Nachweis Farbstoffe," 1908, I, 126), whilst the results of Meyer and Fischer (A., 1913, ii, 167) are considerably extended. The absorption of pp'-dihydroxytriphenylmethane in alcohol is similar to that of the faded benzaurin solution; no band corresponding with that exhibited by benzaurin at 2300 is observed. It is concluded that the benzaurin first absorbs water with formation

of the quinoid hydrate (I), to which the orange tint is ascribed, and which then passes reversibly into the colourless carbinol (II), the residual colour of the HO CPh-C2H, OH (1) HO

HO >CPh(OH)·CH ̧·OH (II.)

faded solution being due to the small proportion of quinoid hydrate present at equilibrium. The addition of hydrochloric acid to the alcoholic benzaurin solution causes development of an orange colour, two new absorption bands being produced at 1985 and 2490. Further addition of acid intensifies these and also brings out bands at 3760 and 3450. These are due to the formation of the quinoid hydrochloride (cf. Baeyer, A., 1903, i, 811). When kept, the acid solution becomes colourless, owing to the reducing action of the alcohol (cf. Kauffmann and Pannwitz, A., 1912, i, 351). The absorption in 93% sulphuric acid is similar, and the same type of absorption spectrum is also given by solutions of benzaurin in alcoholic potassium hydroxide, indicating that the colour of the alkaline solution is due to the quinoid structure of the monopotassium salt, and that this group is alone responsible for the colour of benzaurin and of the analogous Döbner's violet. In 33% aqueous alkali, benzaurin gives a colourless solution, indicating the formation of the dipotassium salt of the carbinol. F. G. WILLSON.

Photochemical transformations in the triphenylmethane series. III. A. LIFSCHITZ (Ber., 1925, 58, [B], 2434-2440; cf. A., 1921, ii, 365).The transformation of derivatives of di- and triaminotriphenylmethane by exposure to light of short wave-length into the isomeric salts of the dye has been described previously (loc. cit.). Similar observations are recorded with pp'-dihydroxytriphenylmethanes and with derivatives of triphenylmethane. Thus benzaurin which has been decolorised by addition of an excess of alkali hydroxide or cyanide regains its characteristic colour on exposure to light, and this is also the case with phenolphthalein. Triphenylacetonitrile, triphenylmethanesulphonic acid, and triphenylmethyl thiocyanate are changed in such a manner as to produce a salt-like isomeride or triphenylcarbinol and the respective acid; in these cases, coloration of the solution is never directly caused by light. It is emphasised that triphenylacetonitrile and triphenylmethyl thiocyanate are non-electrolytes when pure. The former does not give a trace of colour with concentrated sulphuric acid or sulphuric and acetic acids, whereas the latter gives the reaction for the thiocyanogen ion only after its solution has been heated, illuminated, or preserved. Consequently, the triphenylmethyl deriv. atives must exist in a non-dissociated, homopolar form and an electrically dissociable form containing a heteropolar C-linking, thus affording independent evidence in favour of the views advanced by Hantzsch (A., 1922, i, 24) on the constitution of carbonium salts. The complete course of the action of light on triphenylmethane derivatives is therefore (NR, CH4)3CX →→ [(NR2 CH4)3C]++X' → [(NR2 C&H)2CC H4 NR]',

and the primary photochemical effect consists in the transference of a valency electron from the carbon atom to the group X.

The bearing of the discovery of colourless solutions of triphenylmethyl-derivatives which are good electrolytes on the theories of halochromism advanced by Hantzsch (loc. cit.) and Pfeiffer ("Organische Molekülverbindungen," 1922) is discussed. H. WREN.

Azoxybenzenes and aromatic nitro-derivatives. VII. Ŏrganic molecular compounds. M. GIUA and G. GUASTALLA (Gazzetta, 1925, 55, 646-652). Investigation of the m. p. curves indicates the formation of a compound, m. p. about 64°, containing 3 mols. of 2: 4: 6-trinitrotoluene and 2 mols. of azoxybenzene. The equilibrium curve exhibits two maxima, but one of these results from an abnormal reaction owing to the slowness with which the above compound is formed. The eutectic between the compound and azoxybenzene or 2:4: 6-trinitrotoluene has m. p. 26-7° or 53-7°, respectively (cf. Meisenheimer and Smolnikov, A., 1920, i, 334). The system 2:3: 4-trinitrotoluene-azoxybenzene forms a simple eutectic, which solidifies at 25° and contains about 25% of the trinitrotoluene. The system 3:4: 6-trinitrotoluene-azoxybenzene forms a eutectic, solidifying at 22°, at about 35% of the trinitrotoluene. The system 2: 4-dinitrotolueneazoxybenzene forms a eutectic solidifying at about 16° and containing 31.3% of dinitrotoluene, and 1-bromo-2: 4-dinitrobenzene-azoxybenzene a eutectic solidifying at 16° and containing about 42% of the nitro-compound. T. H. POPE.

41.5%

Azo-compounds and aromatic nitro-derivatives. VIII. Organic molecular compounds. M. GIUA and G. REGGIANI (Gazzetta, 1925, 55, 652661; cf. preceding abstract). The following systems form eutectics containing the given proportions of the former component and solidifying at the temperatures stated: azobenzene-2 : 4-dinitrotoluene, 49-15%, benzene-m-dinitrobenzene, 56-21%, 46-5°; p-amino39.6°; azobenzene-p-nitrotoluene, 46%, 28.6°; azoazobenzene-p-nitrotoluene, about 30%, 34.4°; p-aminoazobenzene-p-nitrochlorobenzene, 53.8°; dimethyl-p-aminoazobenzene-2: 4-dinitrotoluene, about 34%, 52-7°; dimethyl-p-aminoazobenzene-p-nitrotoluene, 30%, 40-8°; dimethyl-pAzobenzene (1 mol.) forms an additive compound 45.3%, 63°. with 2:4: 6-trinitrotoluene (2 mols.), m. p. about 65°. p-Aminoazobenzene (1 mol.) and m-dinitrobenzene (1 mol.) form an additive compound, m. p. about 86°. Dimethyl-p-aminoazobenzene (1 mol.) and 2: 4: 6-trinitrotoluene (2 mols.) form an additive compound, m. p. 82°, which gives a eutectic solidifying at 73° (77.2°) with the latter (former) component.

aminoazobenzene-m-dinitrobenzene,

T. H. POPE.

Effect of sulphonic acid groupings in certain positions in lightening the colour of azo dyes. J. OBERMILLER (Z. angew. Chem., 1925, 38, 1044).— See B., 1925, 982.

Occurrence of free radicals in chemical reactions. III. H. WIELAND, H. VOM HOVE, and K. BÖRNER (Annalen, 1925, 446, 31-48).-During

the decomposition of an arylazotriphenylmethane, free aryl and triphenylmethyl radicals are formed (A., 1922, i, 772). It is now found that when a compound of the acylazotriphenylmethane series, e.g., COPh N:N CPhg, is heated in xylene solution, nitrogen is evolved and a deep carmine-coloured solution is generally obtained. This colour, said to be due to the free R.CO' radicals, gradually fades and a 3-benzpinacolin is formed: R.CO'+Ph ̧C' → R·CO CPh. If this theory is correct, the passing of oxygen through the solution during the decomposition of the azocompound should lead to the formation of the peroxides of the free radicals. Whilst triphenylmethyl peroxide was isolated in most instances, only one acyl radical, carbethoxyl, formed a peroxide, CO,Et O.O.CO,Et, the presence of which could be detected by the liberation of iodine from hydriodic acid. When the thermal decomposition is carried out in carbon tetrachloride solution, the free aryl radical removes chlorine from the solvent with formation of the acid chloride. By heating triphenylmethyl chloride or tri-p-tolylmethyl chloride with a substituted hydrazine in benzene or pyridine solution, hydrazo-compounds are obtained. These yield the corresponding azo-compounds when a chloroform solution of the substance is oxidised by shaking it with an ice-cold aqueous solution of potassium ferricyanide. The thermal decomposition of the azocompounds was carried out in xylene or petroleum solution in an atmosphere of nitrogen or carbon dioxide. By these reactions the following substances were obtained: benzoyltriphenylmethylhydrazine, m. p. 148°; benzoylazotriphenylmethane, m. p. 80-81° (decomp.); p-bromobenzoyltriphenylmethylhydrazine, m. p. 177°; p-bromobenzoylazotriphenylmethane, m. p. 67-68° (decomp.); p-toluoyltriphenylmethylhydrazine, m. p. 136-139°; p-toluoylazotriphenylmethane, m. p.

60° (decomp.); p-dimethylaminobenzoyltriphenylmethylhydrazine, m. p. 192–195°; p-dimethylaminobenzoylazotriphenylmethane, m. p. 77° (decomp.); p. 77° (decomp.); p-dimethylamino-3-benzpinacolin, m. p. 224-226°; benzoyltri-p-tolylmethylhydrazine, m. p. 206-208° (decomp.); benzoylazotri-p-tolylmethane, m. p. 70-72° (decomp.); tri-p-methyl-B-benzpinacolin, m. p. 148— 149°; p-toluoyltri-p-tolylmethylhydrazine, m. p. 176178°; p-toluoylazotri-p-tolylmethane, m. p. 60—65° (decomp.); tetra-p-methyl-ß-benzpinacolin, m. p. 145146°;

p.

p-dimethylaminobenzoyltri-p-tolylmethylhydrazine, m. p. 180°; p-dimethylaminobenzoylazotri-ptolylmethane, m. p. 69-70° (decomp.); ethyl triphenylmethylhydrazinecarboxylate, m. p. 145°; ethyl triphenylmethylazocarboxylate, CPh, N.Ñ.CO2Et, m. 98° (decomp.); ethyl tri-p-tolylmethylhydrazinecarboxylate, m. p. 134-135°; ethyl tri-p-tolylmethylazocarboxylate, m. p. 96° (decomp.). DicarbethoxyDicarbethoxyperoxide was prepared by the interaction of ethyl chloroformate and sodium peroxide in chloroform solution. It is an oil which explodes violently at 45°. R. W. WEST.

Action of thiosemicarbazide on certain aromatic nitro-compounds. M. GIUA and R. PETRONIO (Gazzetta, 1925, 55, 665-673; cf. A., 1923, i, 790; 1924, i, 338).-With aromatic halogenated nitro-derivatives containing a labile halogen

atom, thiosemicarbazide reacts by means of a hydrogen atom of the hydrazine residue, yielding nitro-derivatives of ẞ-phenylthiosemicarbazide, e.g.,

CH2(NO2)3 NH-NH·CS⚫NH2.

With nitro-derivatives containing a labile nitro-group the reaction is somewhat complex. Thus, 3:4:6trinitrotoluene (1 mol.) and thiosemicarbazide (1 mol.) yield 4: 6-dinitro-m-tolyl-3-thiosemicarbazide and 4:6:4' : 6'-dinitrodi-m-tolyl disulphide and probably also the compound, CH2Me(NO2)2 N:N•CS•NH2, resulting from the oxidation of the former by the nitrous acid liberated; when 2 mols. of thiosemicarbazide are used per 1 mol. of 3:4: 6-trinitrotoluene, 4: 6-dinitro-m-tolyl-p-thiosemicarbazide is formed in almost pure condition. With 2:3: 4-trinitrotoluene, a similar reaction takes place.

2: 4-Dinitrophenyl-3-thiosemicarbazide,

C,H,(NO,), NH NH CS NH,

or CH3(NO2)2 NH⚫NH·C(SH):NH, from 1-chloro2: 4-dinitrobenzene, has m. p. 210° (decomp.). In presence of sodium acetate, the reaction yields 2 42' 4'-tetranitrodiphenyl sulphide.

:

24 6-Trinitrophenyl-p-thiosemicarbazide (picryl-ßthiosemicarbazide), obtained from picryl chloride, has m. p. 183-184° (decomp.), and yields picrylazothiocarbamide(?), CH2(NO2)3°N:N•CS NH2, m. p. 166° (decomp.), when treated with ferric chloride. 2: 4-Dinitro-m-tolyl-3-thiosemicarbazide, prepared from 23: 4-trinitrotoluene, has Me NO2 m. p. 203-204°. 2:6:2′ : 6′-TetraS nitrodi-m-tolyl sulphide (I), m. p. 222°, is the principal product of 2 the interaction of 2:3 : 4-trinitrotoluene (1 mol.) and thiosemicarbazide. 4: 6-Dinitro-m-tolyl-B-thiosemicarbazide has m. p. 188° (decomp.). T. H. POPE.

NO (I.)

4-m-Nitrophenylsemicarbazide and certain derivatives. A. Š. WHEELER and T. T. WALKER S. (J. Amer. Chem. Soc., 1925, 47, 2792-2796).— 4-m-Nitrophenylsemicarbazide, pale yellow, m. p. 138-139° (hydrochloride), is obtained by the action of hydrazine hydrate on m-nitrophenylcarbamide. 4-mNitrophenylsemicarbazones of the following ketones are described acetone, yellow, m. p. 210-211°; chloroacetone, pale yellow, m. p. 238° to a dark brown liquid, after sintering at 223°; methyl ethyl ketone, similar, m. p. 205°; acetophenone, m. p. 211-212°; benzophenone, light yellow, m. p. 133—136°; camphor, m. p. 240-242°; and cyclohexanone, m. p. 219– 220°. The corresponding derivative of benzoquinone could not be purified. F. G. WILLSON.

Diazotisation of picramide. L. BLANGEY (Helv. Chim. Acta, 1925, 8, 780–783; cf. A., 1920, i, 887).Picramide is diazotised in sulphuric acid solution by nitrosylsulphuric acid in 24 hrs., the solution then giving an 80% yield of azo-compound when coupled with B-naphthol in glacial acetic acid or ethyl alcohol, the temperature being kept at 2-3° during addition. An orange dye resulted from coupling with B-naphthol-6-sulphonic acid and a bluishviolet dye with B-naphthylamine-6-sulphonic acid. Both are very sensitive to alkalis.

G. M. BENNETT.

Reaction between organic peroxides and organo-magnesium halides. H. GILMAN and C. E. ADAMS (J. Amer. Chem. Soc., 1925, 47, 28162821).-Benzoyl peroxide (1 mol.) reacts with magnesium phenyl bromide (1 mol.) in benzene at 0° to -5°, with formation of phenyl benzoate and benzoic acid. If 2 mols. of the Grignard reagent are applied, the excess reacts with the ester with formation of triphenylcarbinol. Magnesium ethyl bromide yields similarly ethyl benzoate, whilst excess of magnesium n-butyl bromide affords phenyldi-n-butylcarbinol, and magnesium benzyl chloride yields, analogously, phenyldibenzylcarbinol. Succinic peroxide is inert towards magnesium phenyl bromide at low temperatures. At higher temperatures, violent reaction sets in after a period of quiescence, resulting in complex mixtures. Triacetone peroxide reacts with magnesium phenyl bromide in anisole, with production of phenyldimethylcarbinol and phenol, whilst ethyl peroxide in ether affords similarly phenetole and diphenyl. Triphenylmethyl peroxide is practically inert towards magnesium phenyl bromide in a boiling mixture of ether and benzene, whilst in boiling toluene 8.-diphenoxytetraphenylethane is produced. The general reaction between organic peroxides and the Grignard reagent may thus be formulated: R.O.O·R+ R'MgXR.OR'+ROMgX. The large proportion of diphenyl obtained from ethyl peroxide in this reaction suggests analogy between this peroxide and azobenzene (cf. Gilman and Pickens, A., 1925, i, 1336), and indicates the formula Et 0:0 Et for ethyl peroxide. F. G. WILLSON.

Organic peroxides. VIII. Further reactions which appear to proceed according to the R.H scheme. H. GELISSEN and P. H. HERMANS (Ber., 1925, 58, [B], 2396-2399; cf. A., 1925, i, 663).The action of benzoyl peroxide on AB-pentene leads, according to Lippmann (A., 1910, i, 149), to the production of amylene hydride" and a benzoic ester which is hydrolysed to benzoic acid and "di amylene oxide.' It is shown that the course of the change probably follows the authors' RH scheme. Lippmann's" amylene hydride" is probably benzene and the ester is the benzoate of y-hydroxy-4-pentene, CHMe.CEt OBZ. The latter substance, when hydrolysed, gives y-hydroxy-AB-pentene, which immediately becomes isomerised to diethyl ketone and thence converted into the substance, CEt2:CMe CO Et, which constitutes the "diamylene oxide."

Benzenesulphonic peroxide (cf. Weinland and Lewkowitz, A., 1903, i, 808; Fichter and Stocker, A., 1925, i, 239) is decomposed by water at 61° in accordance with the RH scheme, yielding benzenesulphonic acid, phenol, and sulphur trioxide.

H. WREN.

Derivatives (esters and sulphonic acids) of anthranilic and methylanthranilic acids. O. KELLER and G. SCHULZE (Arch. Pharm., 1925, 263, 481-502). Since it is still doubtful whether Ewins (J.C.S., 1912, 101, 544) was correct in stating that damascenine (from Nigella damascena) is identical, and not isomeric, with the methyl ester of damasceninic acid, a number of esters of anthranilic and methylanthranilic acid have been investigated, and other

experiments made. Keller's own results (A., 1908, i, 283) tend to confirm Ewins' statement, in that his so-called methyldamascenine (from Nigella aristata), which is admitted to be the above methyl damasceninate, is in part converted into damasceninic acid when its hydrochloride is crystallised from water. The following esters of anthranilic and N-methylanthranilic acid, on the other hand, are stable towards cold or hot water, or even hot dilute hydrochloric acid, but their hydrochlorides are hydrolytically dissociated in aqueous solution, and in this they again differ from damascenine.

The esters in question were prepared by the usual methods from the parent acid and the b. p. of each was determined by Siwoloboff's method. Methyl anthranilate has m. p. 24°, b. p. 256°; its hydrochloride crystallises with 1H2O and has m. p. 178°. Ethyl anthranilate has b. p. 264°; hydrochloride, m. p. 168°. n-Propyl anthranilate has b. p. 270°; hydrochloride, m. p. 160°. Esters with alcohols of higher mol. wt. were not obtainable by the ordinary procedure. Methyl N-methylanthranilate (m. p. 22°, b. p. 255°) yields a hydrochloride, m. p. 137°, and the corresponding ethyl ester (b. p. 266°) yields a hydrochloride, m. p. 127°. Methylanthranilic acid forms no sodium salt in sodium carbonate solution; from such solution the acid is readily extracted by ether.

The opinion of Willstätter and Kahn (A., 1904, i, 235) that when sodium anthranilate is treated with an excess of methyl iodide in alkaline solution the sole product is methylanthranilic acid, and not the dimethyl-derivative, is confirmed.

As a preliminary to an attempt to synthesise damasceninic acid by another method, various

sulphoanthranilic acids have been prepared. When anthranilic acid is sulphonated by weakly fuming sulphuric acid at 180°, it yields primarily 2-amino5-sulphobenzoic acid, but this is partly converted during the reaction, and also gradually when boiled with water, into sulphanilic acid. Attempts to prepare 2-amino-4-sulphobenzoic acid from 2-nitrotoluene-4-sulphonic acid (Hart, A., 1881, 1144) and acid gave unsatisfactory results. W. A. SILVESTER. 2-amino-3-sulphobenzoic acid from o-bromobenzoic

Reduction of aromatic nitro-cyano-compounds. H. RUPE and H. VOGLER (Helv. Chim. Acta, 1925, 8, 832–838).—A number of nitro-cyanocompounds have been reduced by means of hydrogen and a nickel catalyst, the substance being dissolved in a mixture of ethyl acetate, ethyl alcohol, and water. p-Nitrophenylacetonitrile, o-nitroaniline, and o-nitrobenzylideneaniline are completely reduced to B-p-aminophenylethylamine, o-phenylenediamine, and o-aminobenzylaniline, respectively. In the reduction of m- and p-nitrobenzonitriles the aminobenzaldimine is produced and hydrolysed so that a good yield of the aminobenzaldehyde results. The following derivatives of m-aminobenzaldehyde are described: acetylderivative, m. p. 122°, semicarbazone, decomp. above 280°, oxime, m. p. 195°. In the case of o-nitrophenylacetonitrile and o-nitrobenzonitrile, the aminogroup appears to protect the cyano-group from reduction, the products isolated being o-aminophenyl