with slight decomposition. It is readily soluble. The hydrochloride forms slender, matted needles which decompose in contact with water. N. H. M.

Naphthaphenazine. By P. BRUNNER and O. N. WITT (Ber., 20, 2660-2663). Naphthaphenazinesulphonic acid is obtained when naphthaphenazine is heated with 10 times its weight of 35 per cent. fuming sulphuric acid at 100° for 12 hours. It crystallises in orangered needles, melts above 290°, and is soluble in water and alcohol. In concentrated sulphuric acid it dissolves with a deep orange-brown colour, which becomes orange-yellow on dilution. The sodium salt, CH,N, SO,Na + 2H,O, was prepared. On fusion with potassium hydroxide, a eurhodol is obtained which differs from that previously described (Abstr., 1887, 153), since it dissolves in hydrochloric acid with a red colour, and in concentrated sulphuric acid with a darkgreen colour changing to red on dilution. A similar compound has been prepared by diazotising the eurhodine formed by the reduction of nitronaphthaphenazine.

Cyanonaphthaphenazine, CH,N, CN, is obtained when sodium naphthaphenazinesulphonate is distilled with potassium cyanide or dry potassium ferricyanide. Crystallised from cumene, it melts at 236-237°, and dissolves in concentrated sulphuric acid with a cherryred colour, which changes through orange to yellow on dilution. If heated with hydrochloric acid under pressure, it is decomposed into naphthaphenazine and formic acid, but when heated with alcoholic potash at 220-230° it is partially converted into naphthaphenazinecarboxylic acid. This is sparingly soluble in the ordinary solvents, melts above 360°, and dissolves in concentrated sulphuric acid with a deep-red colour, changing to yellow on dilution. The potassium salt crystallises in white needles and is sparingly soluble in water.

W. P. W. Naphtholcarboxylic Acids. By R. SCHMITT and E. BURKARD (Ber., 20, 2699-2704).-a-Naphtholcarboxylic acid (m. p. 187°) can be prepared by heating sodium a-naphthol with liquid carbonic anhydride in an autoclave at 130°, and is a comparatively stable compound (compare Abstr., 1887, 732), since it is only partially decomposed by prolonged boiling with water, in which it is very sparingly soluble. The aqueous solution is coloured greenish-blue by ferric chloride. The sodium salt, with 3 mols. H2O, crystallises in large, thin, nacreous scales; the ammonium salt forms long needles; the calcium and barium salts crystallise in long needles. The methyl salt, OH CoH COOMe, melts at 78°, the ethyl salt at 49°, and the phenyl salt at 96°. The acetyl-derivative, OAC CH COOH, melts at 158°; the bromo-derivative, OH CH,Br-COOH, melts at 238°; the nitro-derivative,

OH CH(NO) COOH,

melts at 202°, and yields ẞ-nitro-a-naphthol when heated with lime; the amido-derivative melts above 200°, and its acetyl-compound at COO. Metadiazonaphtholcarboxylic acid, OH·C1H<>, and CoHN:N>, parazobenzenesulphonic acid-a-naphtholcarboxylic acid,

185°.

SO2H·CH, N2 C10H5(OH)·COOH,

were also obtained, and the latter on reduction with zinc and hydrochloric acid yields an amido-a-naphtholcarboxylic acid which crystallises in colourless, prismatic needles, is very sparingly soluble in water, and melts above 200°, but differs from the amido-derivative just described since its acetyl-compound melts at 195°.

When sodium B-naphthol is similarly heated with liquid carbonic anhydride in an autoclave at 130°, B-naphtholcarboxylic acid is obtained, and is separated by treating the product with ammonium carbonate and precipitating with hydrochloric acid. This acid readily decomposes on heating, and shows all the properties of Kauffmann's acid (Abstr., 1882, 1068). Ferric chloride colours its aqueous solution a pure blue. The ammonium salt crystallises in yellow needles, whilst the barium, calcium, and silver salts resemble the corresponding salts of the a-acid. The methyl salt melts at 76°, and the ethyl salt at 55°.

When sodium B-naphthol is heated at 280-290° in a current of carbonic anhydride, absorption of the gas rapidly takes place, and a product is obtained consisting of B-naphthol, undecomposed sodium B-naphthol, and B-naphtholcarboxylic acid. This acid is extremely stable, and crystallises from water in lustrous, rhombic, yellow scales, which melt at 216° without decomposition, and are readily soluble in alcohol and ether, soluble in toluene, benzene, and chloroform, and sparingly soluble in hot water. Ferric chloride colours the aqueous

solution blue.

W. P. W.

Terpenes. Part VI. By O. WALLACH (Annalen, 241, 315-328). -The compound which the author (Abstr., 1887, 967) recently described as terpene nitrite is terpinene nitrosite. It forms monoclinic crystals; a b c = 1·0103: 1:066978; ß = 80° 31'.

Terpinene nitrolethylamine, NHEt C10H15 NOH, is obtained by boiling for a short time an alcoholic solution of the nitrosite with a strong aqueous solution of ethylamine. The crude product is poured into water, the precipitate dissolved in hydrochloric acid, and the base reprecipitated by ammonia. The base melts at 130-131°, and dissolves in boiling alcohol, ether, chloroform, and in warm dilute solutions of alkalis. The hydrochloride, C12HN,O,HCl, is crystalline, and dissolves freely in water and alcohol. The nitroso-compound melts at 132-133°. It is decomposed by boiling with an excess of hydrochloric acid, yielding hydroxylamine.

Terpinene nitroldiethylamine, NEt C10H15: NOH, melts at 117-118°. Terpinene nitrolmethylamine, NHMe C10H18: NOH, crystallises in prisms and melts at 141°. The dimethylamine, NMe C10H15: NOH, melts at 160-161°. It dissolves in chloroform.

The amylamine-compound is less soluble in alcohol and ether than the preceding substances. It melts at 118-119°. The piperidine, C10H16NO,NC5H10, melts at 153-154°. It is insoluble in alkalis, but its salts are freely soluble in water. The hydrochloride is obtained as an oil on passing dry hydrogen chloride into an ethereal solution of

the base.

Terpinene nitrolamine is formed by adding ammonia to a hot

alcoholic solution of terpinene nitrosite. After recrystallisation from hot water it melts at 116-118°.

By adding a mixture of nitric acid and amyl nitrite to carvene or citronene saturated with dry hydrogen chloride, Maissen (Gazzetta, 13, 99) obtained a crystalline compound meiting with decomposition at 114-115°. The author has obtained the same or similar derivatives from cinnamene and dipentene. They melt at 109° and 110111° respectively, and act on organic amines, yielding crystalline bases. W. C. W.

Constitution of some Pyrroline-derivatives. By G. CIAMICIAN and P. SILBER (Ber., 20, 2594-2607; compare Abstr., 1887, 597). -Dibromodiacetylpyrroline, C,NHAc,Pr2, is prepared by the action of bromine vapour on a warm solution of 2 grams of pyrrylenedimethyldiketone in 700 c.c. of water. It crystallises from alcohol in white needles melting at 171-172°, insoluble in water, soluble in alcohol, ether, and in alkaline carbonates. Nitric acid oxidises it readily at the ordinary temperature to dibromomaleïmide; the constitution of the base is therefore [Br2: Ac2 = 3: 4:2:5].

Nitrodibromacetylpyrroline, C,NHBr2Ac-NO2 [Br2 Ac: NO2 = 3:42:5], is formed when dibromodiacetylpyrroline (8 grams) is dissolved in fuming nitric acid (80 grams), and crystallises from alcohol in long, white needles melting at 206°. It is soluble in alcohol, ether, ethyl acetate, hot glacial acetic acid, and benzene, very sparingly soluble in water, insoluble in light petroleum. Alkaline carbonates dissolve it readily with intense yellow colour.

Dinitrodibromopyrroline, C,NHBr2(NO2)2 [= 3:4:25], is obtained by the action of a well-cooled mixture of sulphuric and fuming nitric acids on the mononitro-compound. It crystallises from water in large, yellow plates (with 1 mol. H2O), which melt at about 169° with decomposition; it is readily soluble in ether, alcohol, hot water, and hot benzene, and dissolves in alkaline carbonates with evolution of carbonic anhydride. If the mixed acids are allowed to act on the mononitro-compound at the ordinary temperature, dibromomaleamide, melting at 227°, is formed. The latter is also formed when dinitrodibromopyrroline is heated at 165°; nitric oxide is evolved.

When dinitrodibromopyrroline is heated with sulphuric acid (20 parts) it is converted quantitatively into dibromomaleic acid. It is probable that the imide of dibromomaleïc acid, and, therefore, maleïc acid also, are symmetrically rather than unsymmetrically constituted: CBrCO、 CBr2 CO (Compare Anschütz,

CBrco>NH, rather than <; CỎ NH>

Abstr., 1887, 916).

:

=

Dibromopyrrolinedicarboxylic acid behaves towards fuming nitric acid in a manner similar to dibromodiacetylpyrroline; dinitrodibromopyrroline [NO, NO, Br: Br 2: 5:34] is formed identical with that obtained from dibromodiacetylpyrroline. reaction shows that the two carboxyl-groups in pyrrolinedicarboxylic acid have the positions 2: 5.

The

Methyl dibromopyrrolinedicarboxylate, C,NHBr,(COOMe), is ob

tained by dissolving methyl pyrrolinedicarboxylate (3 grams) in water (1 litre), and saturating the lukewarm solution with bromine vapour. The yield is 45 grams of pure product. It crystallises from alcohol in long, white needles, melting at 222°, soluble in ether, almost insoluble in water. When 2 grams of the salt is added to 40 grams of fuming nitric acid at -18°, and the whole poured into 400 c.c. of ice-water, and treated with potash (30 grams), the compound C,H,BrNO, is obtained. It is a crystalline compound, melting at 168-171° with decomposition, soluble in ether, alcohol, and hot benzene, rather sparingly soluble in water, and insoluble in light petroleum. It dissolves in alkaline carbonates with evolution of carbonic anhydride. The constitutional formula CBrO C(NOH).COOMe is suggested for it.

Methyl dibromacetylcarbopyrrolate, CNHBr2Ac-COOMe, is prepared in a manner similar to the methyl salt of the bromodicarboxylic acid, which it completely resembles in its behaviour towards fuming nitric acid.

Dibromacetylmethylpyrroline, C,H,Br2NO, is prepared by treating a solution of 2 grams of acetylmethylpyrroline, melting at 85-86° (Abstr., 1886, 719), with an excess of bromine. It crystallises from dilute alcohol in long, white needles, of a silky lustre, melts at 161— 162°, dissolves in ether, carbon bisulphide, and chloroform, and is sparingly soluble in boiling water. When the finely-powdered compound is warmed with fuming nitric acid, dibromomaleïmide (m. p. 227°) is formed. The constitution of acetylmethylpyrroline is therefore [Ac: Me = 2:5].

In order to obtain further evidence as to the constitution of pyruvyl methyl ketone and Schwanert's carbopyrrolic acid, tribromacetylpyrroline and methyl tribromocarbopyrrolate were converted into dibromomaleimide by the action of nitric acid.

Dibromonitracetylpyrroline, C.NHBr2Ac NO, [Br: Br: Ac: NO, = 23:54], is prepared by the action of bromine on nitracetylpyrroline, melting at 197° (Abstr., 1885, 810 and 992). It crystallises from alcohol in needles melting at 175°, soluble in ether, warm alcohol, and glacial acetic acid, sparingly soluble in warm water, insoluble in light petroleum. The non-identity of this compound with the dibromo-derivative described above, and the probability that in the nitracetyl-compound (m. p. 197°) the acetyl-group has the a-position, make it probable that the nitracetyl-compound has the constitution [NO, : Ac = 3 or 4 : 2 or 5].

A table of all pyrroline-derivatives (halogen-derivatives and ethers excepted) of known constitution is given. N. H. M.

Synthesis of Pyridine and Piperidine-derivatives. By C. PAAL and C. STRASSER (Ber., 20, 2756-2766).-Diphenacylacetic acid (Abstr., 1887, 261) when treated with alcoholic ammonia yields the ammonium salt of ax'-diphenyldihydropyridine-y-carboxylic acid, C.NH,Ph,COONH. This salt is soluble in water and concentrated hydrochloric acid; on acidification with sulphuric acid, the corresponding acid separates, but is quickly decomposed. On dry distillation, ammonia is given off, and aa'-diphenylpyridinecarboxylic acid,

C2NH2Ph2 COOH, is produced, which after purification crystallises in delicate, white needles or prisms, melting at 275°, soluble in alcohol, sparingly soluble in chloroform. The acid is not altered by nitrous acid, acetic chloride, or oxidising agents. Its ammonium salt does not exist in the free state; the silver salt is a heavy, white precipitate; the chromate a dark-red, amorphous precipitate; the aurochloride is crystalline.

aa-Diphenylpiperidine-y-carboxylic acid, C,NH,Ph2 COOH, obtained together with the above acid, and separated from it by its greater solubility, forms crystalline crusts; it melts at 339°, and sublimes without decomposition, its alkaline salts are very soluble, the barium and silver salts are white precipitates. Its nitroso-derivative crystallises in pale-yellow, glistening needles melting at 159°, and is soluble in ether and alcohol.

ax-Diphenylpyridine, C,NH,Ph, obtained by the distillation of the calcium salt of the carboxylic acid with lime, crystallises in long, glistening needles melting at 81-82°; its platinochloride forms yellow needles, and the aurochloride a crystalline precipitate; the methiodide crystallises in needles melting at 203°.

aa-Diphenylpiperidine, C,NH,Ph2, obtained by the hydrogenation of the above base, is a thick, pale-yellow oil; its hydrochloride crystallises in white needles; the platinochloride and the aurochloride and the nitroso-derivative crystallise with difficulty. V. H. V.

3-Methylpyridine and 3-Methylpiperidine. By C. STOEHR (Ber., 20, 2727-2733). The picoline obtained by distilling strychnine with lime (Abstr., 1887, 604) proves on further examination to be B-picoline, since nicotinic acid is found to be the sole product on oxidation with 2 per cent. permanganate solution. Some quantity of the base was prepared to enable an examination of its properties to be made, and the results are compared with those of previous observers. B-Picoline thus obtained boils at 145-159° after two fractionations; by conversion of this product into the mercurochloride and regeneration of the base, it gives a product which mostly passes over between 148° and 149° (compare Hesekiel, Abstr., 1885, 812). The platinochloride, (C.H,N)2,H2PtCl + HO, has the properties of the salt described by Baeyer (Annalen, 155, 285), melts when dry at 195, loses 1 mol. H2O when allowed to remain in a desiccator, and when heated at 120° loses in addition 1 mol. HCl, the compound thus obtained, (C,H,N)2,HCl, PtCl, melting at 211-212°. The aurochloride melts at 182-183°. The mercurochloride, C,H,N,HC1,2HgCl2 (compare Hesekiel, Abstr., 1886, 256), crystallises from hot water in slender, ramifying needles, from dilute hydrochloric acid in indented scales, or long, compact needles, and from concentrated hydrochloric acid, in which it is very soluble, in small, well-formed prismatic crystals melting at 139-140°. The picrate crystallises in six-sided scales melting at 142-143°.

3-Methylpiperidine, obtained by reduction of the B-picoline in alcoholic solution with sodium, is readily soluble in water, and yields a hydrochloride, crystallising in dazzling, white needles.

W. P. W.