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residue filtered from the photosantonic acid which separates on cooling. A further quantity of photosantonic acid is precipitated by adding water. The solution is then nearly free from photosantonic acid and still contains almost the whole of the isomeride. It is treated with sodium carbonate (which dissolves the photosantonic acid alone) and extracted with ether. It separates from its alcoholic solution in thick, triclinic crystals, rather soluble in ether, and sparingly in water. When heated at 100°, it is converted into the lactone, C15H2004. It is dextrorotatory, [a] = +124° 17'. Photosantonic acid has nearly the same specific rotatory power, but is lævorotatory. Isophotosantonic acid dissolves in alkalis and in warm solutions of alkaline carbonates; the solutions are orange-red. The barium salt, (C15H2105) 2Ba + H2O, is an amorphous powder, readily soluble in alcohol and in water. The monacetyl-compound crystallises from alcohol in transparent needles which melt at 183°; it is dextrorotatory, [a] = +58° 16'. The diacetyl-compound is very sparingly soluble; it melts at 163-166°. It is very unstable, and when often recrystallised changes to the monacetyl-derivative.

The results above described point to the following constitutional formulæ for the lactones of isophotosantonic and photosantonic acids respectively :

[blocks in formation]

Cinchol. By O. HESSE (Annalen, 234, 375-379).—A further comparison of the properties of cinchol and Liebermann's oxyquinoterpene or cholestole (Abstr., 1885, 1075) confirms the author's previously expressed opinion (Abstr., 1885, 1076) that these two substances are identical. They both melt at 115°, and are identical in crystalline form. The acetates melt at 124°, and also exhibit identical crystalline forms.

W. C. W.

Alkaloids. By O. DE CONINCK (Compt. rend., 103, 640-641.)— Piperidine methiodide gives no colour reaction with potassium hydroxide (Abstr., 1886, 897), and this difference furnishes a means of distinguishing between a pyridic base and its hexhydride.

Cicutine methiodide also gives no colour reaction, but the solution acquires an amber tint. The reaction is always obtained with collidines, and therefore will most probably be given by conyrine, the collidine of which cicutine is the hexhydride.

No similar colour reaction is obtained with the methiodides of aniline, orthotoluidine, or metaxylidine. When methiodides of pyridic bases are mixed with a fragment of solid potassium hydroxide

and sufficient water to form a paste, and then heated, a peculiar odour is developed owing to the formation of pyridic dihydrides.

No similar reaction is given by methiodides of pyridic hexhydrides, nor by the methiodides of aniline and its homologues. C. H. B.

Extraction of Pyrroline from Animal Oil. By G. L. CIAMICIAN and M. DENNSTEDT (Gazzetta, 16, 336).—Pyrroline may be extracted as the potassium-derivative by using caustic potash instead of the metal as heretofore practised. The reaction is probably C1H ̧NH + KOH = CH,NK + H2O; the excess of potash serving as a dehydrating agent. The fraction of the oil, freed previously from nitriles, which passes over at 125-140°, is heated in an oil-bath with an excess of fused potash, using a reflux apparatus. At the conclusion of the reaction, the liquid separates into three layers, the heaviest of which is the excess of potash, the next the potassium compound, and the lightest the unaltered hydrocarbons. On cooling, the potassium compound solidifies, and is washed with anhydrous ether. The substance thus obtained, distilled in a current of steam, yields pyrroline of boiling point 130-138°; with chloroform, it yields chloropyridine (Abstr., 1881, 820). V. H. V.

Pyridine Bases. By A. LADENBURG (Compt. rend., 103, 692695; see also Abstr., 1884 and 1885).-a-Methylpyridine (picoline), CNH, is obtained in the form of hydriodide by heating pyridine methiodide at 300°. The base boils at 128-129°, and is miscible with alcohol and water; sp. gr. at 0° 0.9656. It forms a characteristic mercuriochloride, C,NH,,HC1, HgCl2, by means of which it can be isolated in a state of purity; this compound is very soluble in hot water, but only slightly soluble in cold water. B-Methylpyridine is best prepared by Zanoni's method of heating glycerol and acetamide with phosphoric anhydride. It boils at 142°; sp. gr. at 0° = 0.9771. The platinochloride crystallises with 1 mol. H2O and melts at 214°; the aurochloride is anhydrous and melts at 183°; the mercuriochloride is also anhydrous, melts at 143°, and forms slender needles which can be crystallised from water. -Methylpyridine is formed only in small. quantity by the action of heat on pyridine methiodide; it boils at 144-145°; sp. gr. at 0° = 0·9708. The platinochloride is anhydrous, melts at 225°, and is only slightly soluble in water. aa-Dimethylpyridine is isolated from the fraction of animal oil boiling at 138145° by means of the mercuriochloride, C,NH,,HCl,HgCl2, which can be crystallised from water, and melts at 183°. When decomposed, it yields lutidine boiling at 142-143°; sp. gr. at 0° 09424. The aurochloride forms yellow needles which melt at 124°; the platinochloride crystallises in large monoclinic crystals isomorphous with B-picoline platinochloride, although the former is anhydrous, whilst the latter contains 1 mol. H2O. The picrate is only slightly soluble in water and melts at 159°. When the base is oxidised, it yields a bibasic acid, C,NH,(COOH)2, crystallising in beautiful needles which melt at 226°, and at the same time decompose into pyridine and carbonic anbydride. --Dimethylpyridine exists in large quantity in Dippel's

oil, and can be isolated from the fraction which boils at 155-160° by acidifying with hydrochloric acid and adding mercuric chloride. The precipitated mercuriochloride, 2(C,NH,,HCI,2HgCl2) + H2O, is repeatedly recrystallised, and forms beautiful needles which melt at 129°. When decomposed, it yields the base; this boils at 157°, and is only slightly soluble in cold water, still less soluble in hot water. The platinochloride is somewhat soluble, crystallises readily, and melts at 219-220°. The aurochloride, C,H,N,HAuCl, is less soluble and does not crystallise so well. The picrate melts at 180°. This lutidine is identical with the lutidine prepared synthetically by Hantzsch. When oxidised, it yields lutidinic acid, which crystallises in plates which melt at 235°.

a-Ethylpyridine is the principal product of the action of a high temperature on pyridine ethiodide; it boils at 150°, is miscible with alcohol, but is only slightly soluble in water. The platinochloride is somewhat soluble in water, and melts at 168-170°; the aurochloride melts at 120° and crystallises readily from hot water; the picrate melts at 110°. When the base is oxidised, it yields picolinic acid only. -Ethylpyridine is also formed in smaller quantity by the action of heat on pyridine ethiodide, and is separated from its isomeride by taking advantage of the comparative insolubility of its salts, especially the platinochloride or ferrocyanide. The base boils at 165°; sp. gr. at 0° = 0·9522. The platinochloride melts at 208°, the picrate at 163°, the aurochloride at 138°. The ferrocyanide is precipitated even from very dilute solutions. When the base is oxidised, it yields isonicotinic acid. a-y-Diethylpyridine is also obtained in small quantity by the action of heat on pyridine ethiodide; it boils at 187-188°, has a disagreeable odour, and is only slightly soluble in water. When carefully oxidised, it yields lutidinic acid which melts at 235°.

a-Isopropylpyridine, obtained by heating pyridine with propyl or isopropyl iodide at 300°, boils at 158-159°, is slightly soluble in water, and has a very disagreeable odour; sp. gr. at 0° 0·9342. The platinochloride, (CHN)2, H2PtCle, is somewhat soluble and melts at 168°; the aurochloride crystallises from dilute solutions in yellow plates which melt at 91° and are only slightly soluble in water; the picrate forms yellow needles which melt at 116°. When the base is oxidised by potassium permanganate, it yields picolinic acid. -Isopropylpyridine is obtained in smaller quantity by the same reaction, and is separated by means of the platinochloride, which is only slightly soluble in water, and melts at 203°. The base boils at 177-178°; sp. gr. at 0° = 0.9439. When oxidised, it yields isonicotinic acid.

C. H. B.

Quinoline. By A. CLAUS and F. COLLISCHONN (Ber., 19, 2502— 2508). The authors describe a number of halogen additive products of the propio-haloïd compounds of quinoline. Quinoline propiobromide is easily formed when its constituents are heated alone, or better, with alcohol, at 90-100°. It is easily soluble in alcohol and water, and crystallises from water in colourless plates containing 2 mols. H2O, and melting at 66°; from absolute alcohol, it separates in anhydrous crystals melting at 148°. It is easily soluble in chloroform, and from this solution crystallises with 1 mol. CHCl, in quadratic

prisms which gradually lose chloroform and become opaque, soften at 65°, and melt with evolution of chloroform at 128-129°. Quinoline propiodide forms yellow anhydrous crystals melting at 145°, and becoming rapidly discoloured in the light. This also crystallises with 1 mol. CHCI, in quadratic prisms which begin to evolve chloroform at 92°. Quinoline propiochloride cannot be easily prepared directly from its constituents, but is best obtained by acting on the corresponding bromide with silver chloride. It is very soluble in water, and crystallises in colourless prisms or plates containing 1 mol. H2O and melting at 95°. The hygroscopic anhydrous salt melts at 135°; it also crystallises with 1 mol. CHCl, in quadratic prisms melting at 79°. The additive products were obtained by treating a chloroform solution of the propiohaloïd salt with the halogen.

Quinoline propiobromide dibromide, C,NH, PrBrs, forms glistening, red, triclinic crystals melting at 93°. The di-iodide forms brown metallic needles melting at 60°. The dichloride forms yellow scales melting at 60°. The tetriodide, C,H,N.PrBrI, yields small, almost black needles having a green fluorescence and melting at 49°.

Quinoline propiodide dibromide forms orange triclinic crystals melting at 77°. The di-iodide forms thin, bronze-coloured scales melting at 62°. The dichloride forms yellow needles melting at 87°. The tetrabromide, C,NH, PrIBr, is a very unstable orange-red powder which evolves bromine at the ordinary temperature, and gave no constant melting point (48-58°). The tetriodide forms iodine-coloured plates melting at 50°. The tetrachloride crystallises in needles which show the high melting point 144-145°. It is also formed when quinoline propiochloride is treated with iodine trichloride, and may therefore really be quinoline propiochloride iodide trichloride. When boiled with water, it is gradually decomposed into quinoline propiochloride. Similar migration of the halogen-atoms may also very likely take place in others of the mixed haloïd compounds.

Quinoline propiochloride dibromide forms orange crystals melting at 84-85°. The di-iodide melts at 61-62°. The dichloride is very unstable and could not be obtained in a pure state. A tetriodide is easily formed, but could not be obtained in a pure state.

All these additive compounds decompose when heated at 150-200°, propyl haloïd salts, quinoline haloïd salts, and halogenised and alkylated quinolines being amongst the products of decomposition. These decompositions are being studied. All the above temperatures are uncorrected. L. T. T.

Isoquinoline and its Derivatives. By S. GABRIEL (Ber., 19, 2354-2363; compare Abstr., 1886, 812).-Dichlorisoquinoline,

CH: CCI
C.H. CCI: N.

is prepared by heating homo-orthophthalimide (8 grams) with phosphorus oxychloride (24 grams) for three hours at 150-170°. The product is poured into alcohol (5 vols.), the mass of crystals so obtained treated with soda until alkaline, filtered, and recrystallised from alcohol. It is readily soluble in hot alcohol, cold chloroform,

ether, and benzene; it boils at 305-307°. The alkaline motherliquor obtained in the preparation of this compound, when treated .CH, CO. with hydrochloric acid, yielded the chloro-derivative C.H<CCI:N> or C.H.CCI:N CH: C(OH); this crystallises from boiling alcohol in long needles melting at 195-197° with evolution of gas. It is rather soluble in hot alcohol, sparingly in hot benzene and in chloroform; it dissolves in alcohol, but not in ammonia. The methyl-compound, C,H,MeCINO, is obtained by dissolving half a gram of the substance in methyl alcohol (10 c.c.), adding methyl iodide (2 grams), and heating at 100°. It forms slender, white crystals, readily soluble in alcohol, ether, benzene, &c., insoluble in alkali. It melts at 66-67°, and has an odour of fruit.

CH: CCI.

Chlorisoquinoline, C.H.<CH:N->, is obtained by reducing the dichloro-compound with phosphorus and hydriodic acid at 150170°, or with tin and hydrochloric acid. It melts at 47-48°, and boils at 280-281° under 753 mm. pressure, and is readily soluble. CCI: CPh

Methoxyphenylchlorisoquinoline, CHCOMe): N>, is formed when phenyldichlorisoquinoline (1 gram) and sodium methoxide are heated for three hours at 100°. It crystallises from alcohol in needles melting at 76°, readily soluble in ether, benzene, &c. It dissolves also in strong hydrochloric acid, but is precipitated by water. When heated with fuming hydrochloric acid at 100°, it is converted, with evolution of methyl chloride, into the compound C16H10OCINO, probably chlorisobenzal phthalimidine, CH,CCCP. It crystallises from alcohol in slender, lustrous needles, melting at 211-212°, moderately soluble in ether and cold alcohol, readily in glacial acetic acid, benzne, &c. The formation of this compound is analogous to that of isobenzalphthalimidine from phenylethoxyisoquinoline (Abstr., 1886,

631).

CC1:CPh

CH-CCI

Ethoxychlorisoquinoline, CHC(OEt): N, is prepared by heating dichloroisoquinoline with alcoholic soda at 100°. It forms readily soluble needles melting at 37-37.5°.

The methoxy-derivative, CH,NOCI, is prepared in a similar manner. It melts at 73-74°, and is isomeric with the methyl-compound obtained from chloroxyquinoline. When heated at 150° in a current of dry hydrogen chloride, it is converted into oxychlorisoquinoline, CH: CCI CH<CONHThis crystallises from dilute alcohol in slender needles melting at 218-220°; it dissolves rather readily in ether, easily in alcohol and chloroform; it is also readily soluble in dilute CH: CCI aqueous soda. The methyl-derivative, CH<CO-NMe>, crystallises in long, broad needles which melt at 111-112°; it is readily soluble. Oxychlorisoquinoline is formed in small quantities in the preparation of ethoxychlorisoquinoline.

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