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To decide as to the correctness of Elbs' result, ethyl parabromobenzoate was prepared by the etherification of the corresponding acid; the compound obtained differs in boiling point (262°) from parabromobenzyl ethyl ether (243°), and is saponified immediately in the cold by alcoholic potash. The formation of parabromobenzoic acid from the ether is due to oxidation.

As a further point of difference, it is noted that parabromobenzyl ethyl ether on nitration forms parabromobenzaldehyde, whilst ethyl parabromobenzoate under the same conditions yields ethyl nitrobromobenzoate, COH,Br(NO2)·COOEt [COOEt: NO2: Br=1:3: 4].

In conclusion, some details are given as to the best method of preparing parabromobenzoic acid by the oxidation of the corresponding bromotoluene. V. H. V.

Derivatives of Phenylamidoacetic Acid. By O. REBUFFAT (Gazzetta, 17, 231–236).-Acetylphenylamidoacetic acid,

NPhAc CH, COOH,

obtained by heating phenylamidoacetic acid with acetic anhydride in presence of benzene, crystallises in micaceous laminæ, melting at 190-191°, very soluble in water and alcohol, sparingly soluble in

benzene.

Benzoylphenylamidoacetic acid, NPhBz.CH, COOH, is prepared in like manner to the above, and may be purified by means of its sodium salt, which crystallises on slow evaporation in large, tabular crystals. The acid is a white, amorphous precipitate, melting at 63°; the copper salt is an amorphous, green precipitate.

In the course of the preparation of phenylamidoacetic acid from aniline and monochloracetic acid, the formation of a black, resinons substance is observed, the quantity of which increases with the quantity of water in excess of a certain proportion, and the time employed in evaporating the solution for crystallising the amido-acid. Thus if one molecular proportion of monochloracetic acid and two of aniline are heated together, this black resin is the sole product. If this substance is purified from the accompanying aniline hydrochloride and phenylamidoacetanilide residue, dissolved in hydrochloric acid, and then reprecipitated with water, an acid is obtained crystallising in micaceous scales which decompose at 190-195°. Analysis points to phenylylycinephenylamidoacetic acid,

NHPh•CH, CONPh•CH, COOH. When impure, the acid rapidly turns black; it is sparingly soluble in water, but soluble in alcohol; it readily decomposes carbonates.

V. H. V.

Derivatives of Hydrothiocinnamic Acid. By S. BONDZYNSKI (Monatsh. Chem., 8, 349-364; compare Abstr., 1886, 325).-Hydrothiocinnamic acid, CHPh: C(SH)·COOH, obtained by heating "benzylidene-rhodanic acid," C,H,CH: C(SH) CO-SCN, with baryta-water, forms a yellowish, crystalline powder, and melts at 119°. It is easily soluble in alcohol, ether, benzene, &c., almost insoluble in water. The alkaline salts are easily soluble in alcohol and water, the salts of the

heavy metals are insoluble. When treated with iodine in carbcn bisulphide solution, bisulphid-cinnamic acid,

CHPh: C(COOH)•S•S•C(COOH): CHPh,

is obtained; this crystallises in slender, yellow needles melting at 179°. The sodium salt of this acid is an orange-yellow, amorphous substance easily soluble in water, quite insoluble in alcohol. The potassium salt is soluble in both alcohol and water. The barium and magnesium salts are easily soluble in water; the salts of the heavy metals are quite insoluble in water. Bromine acts on hydrothiocinnamic acid in the same manner as iodine. Hydriodic and hydrobromic acids do not combine with the acid.

When benzylidene-rhodanic acid is treated with a mixture of nitric and sulphuric acids, a violent action takes place, and two substances are obtained, one readily soluble in alcohol, the other sparingly soluble. The former, which crystallises in bright-yellow, rhombic prisms, is nitrohydrothiocinnamic acid; when purified by means of the barium salt and recrystallised from alcohol, it melts at 240°. The second, nearly insoluble substance appears to be a nitrobenzylidene-rhodanic acid; it melts at 263-265°. This method, however, does not give a good yield; the author therefore prepares orthonitrohydrothiocinnamic acid by heating together in alcoholic solution orthonitrobenzaldehyde and thiocyanic acid. The resulting orthonitrobenzylidene-rhodanic acid is a white, crystalline powder, insoluble in water, soluble in alcohol; it melts at 188-189°. When this substance is treated with barytawater, an acid barium salt of the acid is obtained in orange crystals; it is therefore necessary to saponify the acid by heating it with excess of crystallised barium hydroxide.

When the nitro-compound is reduced with alcoholic ammonium sulphide, a small quantity of amidohydrothiocinnamic acid is formed. When reduced with ferrous sulphate, it yields orthamidobenzylidenerhodanic acid, CH,(NH2) CH: C(SH)CO,SCN; this forms brilliant, blood-red crystals, which are completely decomposed on heating at 265-269°. The substance still retains acid properties; it is soluble in alkalis and reprecipitated by dilute acids. When heated with acetic anhydride, it gives the diacetate, which crystallises in yellow needles and melts at 189°. A little monacetate is also produced; this forms long, citron-yellow needles melting at 280-285°. Attempts to obtain orthohydrothiocinnamic acid from orthamidobenzylidenerhodanic acid by treatment with baryta were unsuccessful, as also were endeavours to diazotise the latter substance. G. H. M.

Paracoumaric Acid. By G. EIGEL (Ber., 20, 2527-2539).Paracoumaric acid was prepared by the three known methods: from aloes (Annalen, 136, 31), from parahydroxybenzaldehyde (this Journal, 1877, ii, 893), and from paradiazocinnamic acid, and modifications are described by which the yield may be much increased. Methylparacoumaric acid was also prepared by Perkin's reaction from anisaldehyde (Abstr., 1877, i, 40), and by the methylation of paracoumaric acid. A comparison of these acids with naringenic and methylnaringenic acids respectively establishes their identity (this vol., p. 497).

Hydromethylnaringenic acid, formed by the reduction of methylnaringenic acid with sodium, is identical with hydromethylparacoumaric acid; it crystallises in feather-like forms, but after conversion into the sodium salt and treatment with an acid is obtained in long, colourless needles; the crystals of both forms are anhydrous. The silver salt, CHAgO,, crystallises in small needles, is sparingly soluble in hot water, and when dry is unaffected by light; the barium salt, (CH1103)2 Ba + 2H2O, crystallises in cubic forms. The methyl salt, CH1O3, obtained in small quantity only by saturating a solution of the acid in methyl alcohol with hydrogen chloride, is readily prepared by heating the acid (1 mol.), with potassium hydroxide (2 mols.), methyl iodide (2 mols.), and some methyl alcohol at 140° for an hour; it boils at 265-270°, solidifies at 0° to a crystalline mass which melts at 38°, and is identical with methyl hydromethylparacoumarate.

14

When dry paracoumaric acid in ethereal solution is treated with bromine (1 mol.), and the solvent is removed by evaporation in a current of air, colourless crystals of what is perhaps a paracoumaric acid dibromide are obtained; these melt at 97-101° and decompose on drying. Bromoparacoumaric acid dibromide,

OH CH,Br.CHBrCHBrCOOH,

is formed when paracoumaric acid dissolved in acetic acid or absolute ether is treated with an excess of bromine; it crystallises from chloroform in needles and melts at 188°. On treatment with alcoholic potash, it yields bromoparavinylphenol dibromide,

OH CH,BrCHBr CH2Br.

This compound is crystalline, melts at 108°, and yields an acetyl-derivative, C.HBrOAc, melting at 94°.

Methylparacoumaric acid dibromide, OMe CH, CHBr·CHBr COOH, is prepared by the action of bromine on methylparacoumaric acid in equimolecular proportions; chloroform is used as a solvent, and must be removed by evaporation at the ordinary temperature. It forms colourless crystals, which melt at 149° when heated rapidly, and at 168° when slowly heated; heat readily decomposes it. The methyl salt has been already described (this vol., p. 488); when treated with alcoholic potash, it yields two acids crystallising in needles, one of which is soluble in hot water, and melts at 158-168°, whilst the second is soluble in hot alcohol, and melts at 127-132'. If methylparacoumaric acid dibromide is heated with aqueous potash, bromoparavinylanisoïl, OMe CH, CH: CHBr, is obtained; this crystallises from alcohol in scales, melts at 54.5°, is volatile with steam, and has an odour and taste resembling that of anise and fennel.

On treatment with an excess of bromine in chloroform solution, methylparacoumaric acid yields bromomethylparacoumaric acid dibromide, OMe CH,Br·CHBr·CHBr·COOH, which crystallises from ether or chloroform in needles, melts at 162°, and is decomposed by alcohol and water. When heated with 30 per cent. aqueous potash, it is converted into bromoparacetyleneanisoil, OMe C,H,BrC CH. compound crystallises from alcohol in scales, melts at 75°, is volatile with steam, and yields a greenish-yellow, feebly explosive precipitate with ammoniacal cuprous chloride solution. W. P. W.

Homo-orthophthalimide. By G. PULVERMACHER (Ber., 20, 2492 -2499; compare this vol., pp. 50, 725).-When a solution of homoorthophthalimide (1 mol.) and sodium (2 mols.) in alcohol is digested with ethyl iodide (2 mols.) at 100°, a-diethylhomo-orthophthalimide, C,H,Et,ÑO2, is obtained; this crystallises from alcohol in white scales, melts at 144°, and is soluble in alkalis. By the further action of ethyl iodide and alcoholic potash on this compound at 100°, triethylhomoorthophthalimide, C,H,Et,NO2, is formed; this is a glistening, white, crystalline mass, which melts at 50°, and is extremely soluble in all ordinary solvents, but is insoluble in alkalis.

.CH, CO.

Homo-orthophthalethylimide, CH. CONE>, is prepared by distilling a solution of homo-orthophthalic acid in ethylamine. It crystallises in yellowish needles, melts at 105°, and is readily soluble in all ordinary solvents and in alkalis. When ethylated, it yields triethylhomo-orthophthalimide, whose constitution therefore is proCEt2 CO. bably represented by the formula C,H<CO NEt>. Diazobenzene chloride and benzaldehyde react with the ethylimide, and form compounds analogous to those obtained by the action of these substances on homo-orthophthalimide (loc. cit.); homo-orthophthalethylimidazobenzene, CHINO N2Ph, crystallises from alcohol in yellow needles melting at 139°, and benzalhomo-orthophthalethylimide,

Ph CH: CH,NO2,

crystallises from acetic acid in stellate groups of yellow needles, melting at 97°.

a-Diethylhome-orthophthalic anhydride, C,H,Et,O,, is obtained when diethylhomo-orthophthalimide is heated with fuming hydrochloric acid at 230°. It crystallises in colourless scales, melts at 53°, and is sparingly soluble in ammonia, but soluble in warm aqueous alkalis. The barium salt, C,H,Et2O,Ba, crystallises in white, silky scales; the silver salt, C,H,Et2O,Ag2, was also prepared. When mixed with soda-lime and distilled over lime, the anhydride yields a red oil, from which diethyltoluene, CH, CHEt, (b. p. 178°), can be separated by fractionating between 170-180°. If the solution of the anhydride in aqueous potash is treated in the cold with hydrochloric acid, a-diethylhomo-orthophthalic acid, COOH CH, CEt COOH, separates as a crystalline precipitate, which after crystallisation from alcohol, melts at 148° and is converted into the anhydride.

=

a-Dibenzylhomo-orthophthalimide, C,H(Č,H,)2NO2, obtained by digesting homo-orthophthalimide with sodium and benzyl chloride in alcoholic solution, crystallises in yellow scales and melts at 174°. Unlike the diethylimide, it is insoluble in alkalis, and is only attacked by hydrochloric acid with difficulty even at 300°, when it yields a compound which seems to be the anhydride of a-dibenzylhomo-orthophthalic acid; this crystallises in yellow needles, melts at 191°, and is sparingly soluble in alkalis.

Homo-orthophthalbenzylimide, CH13NO2, obtained by distilling homoorthophthalimide with benzylamine, forms yellowish-green crystals which melt at 127°, and are soluble in alkalis. When heated with

benzyl chloride and an alkali, it yields a-dibenzylhomo-orthophthalbenzylimide (tribenzylhomo-orthophthalimide), C,H,(C,H,).NO,, identical with that prepared in a similar manner from dibenzylhomo-orthophthalimide; this crystallises in yellowish-white scales, and melts at 109°. W. P. W.

Homo-orthophthalimide and the Homologues of Isoquinoline. By S. GABRIEL (Ber., 20, 2499-2506).—Ethyl homo-orthophthalate, COOEt C&H, CH COOEt, is obtained either by treating the silver salt of the acid with ethyl iodide, or by saturating an alcoholic solution of the acid with hydrogen chloride. It is a thick oil with a faint, aromatic odour, boils at 291·5—292.5°, and is not acted on when treated with sodium in alcoholic solution and then digested with ethyl iodide.

a-Methylhomo-orthophthalonitrile, CN-CH, CHMe CN, is prepared by treating a lukewarm alcoholic solution of orthocyanobenzyl cyanide (5.7 grams) with methyl iodide (3 c.c.) and an alcoholic solution of potassium hydroxide (2.25 grams), cooling the mixture when necessary, and finally heating at 100° to complete the reaction; the residue left on distilling off the alcohol is then treated with water, extracted with ether, and the oil remaining after the evaporation of the ether is purified by distillation. It crystallises in large triclinic forms, a b c = 0·9449 : 1 : 1·0809; a = 97° 2′; ß = 103° 12′; 1= 87° 11'; melts at 36-37°, boils at 284-286°, is only slightly volatile with steam, and is readily soluble in the ordinary solvents, sparingly soluble in light petroleum. When the nitrile is dissolved in sulphuric acid, heated at 100° until the reaction is complete, and the product poured into water

CHMe CO

a-Methylhomo-orthophthalimide, C.H.<CONH>, is obtained; this crystallises in compact, glistening prisms, melts at 145°, distils without decomposition, and dissolves in alkalis. On digestion with methyl iodide and alcoholic potash, this compound is converted into trimethylhomo-orthophthalimide (this vol., p. 50). When the methylimide is heated with fuming hydrochloric acid at 190-200° for two hours, it yields a-methylhomo-orthophthalic acid; this is a crystalline powder, which melts at 146-147° and dissolves in ammonia and alkalis. The silver salt, CoH.Ag2O, was analysed.

CMe: CCI

Methyldichlorisoquinoline, CH<-CCI: N->, is prepared by heating a-methylhomo-orthophthalimide (5 grams) with phosphorus oxychloride (15 c.c.) at 190-200° for four hours, extracting the product with water, and heating the crystalline residue with very dilute aqueous soda; the insoluble methyldichlorisoquinoline is then purified by distillation and crystallised from alcohol. It crystallises in long, white needles, and melts at 101-102°. On treating the alkaline filtrate with an acid, it yields methylchloroxyisoquinoline, CMe: C(OH) CHMe CO. CH.CCIN

or C.H-CCI: N->, which crystallises from acetic acid in needles, and melts at 224° with frothing. Homo-orthophthalonitrile, when ethylated under conditions similar

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