mixture at a moderate heat to a small volume and then set it aside to crystallize. Compact, colorless, in part tabular crystals gradually separated out, which melted at 122° C. with a strong evolution of gas. These crystals were readily soluble in water, forming a neutral solution; ether dissolved them less readily. The aqueous solution caused the liberation of iodine from a solution of potassium iodide. Still greater quantities of iodine were formed after acidulating with hydrochloric acid. Sulphurous acid was immediately oxidized to sulphuric acid, with the reformation of scopoline. Upon adding gold chloride to a solution of this oxidation compound in dilute hydrochloric acid a voluminous yellow precipitate separated out, which, however, soon changed into the crystalline scopoline-gold chloride with the evolution of oxygen. When this voluminous precipitate was warmed with the mother liquor it readily dissolved with the copious evolution of oxygen and the separation of a small amount of metallic gold. Upon cooling, this solution yielded characteristic crystals of scopolinegold chloride. Hydrochloride. The hydrochloride of this scopoline oxidation product could be obtained by spontaneous evaporation of its aqueous solution in the form of long, acicular individual crystals, or as small needles in feather-like groups. These crystals turned red at 120° C.; at 132-135° C. they melted with copious evolution of gas. No loss of weight was sustained at 100° C. 0.1542 Gm. yielded 0.1044 Gm. AgCl. Found: HCl. 17.22 per cent. Calc. for CH13NO3.HCI: The above data show that by the action of hydrogen peroxide, scopoline is converted into an unstable oxide, as is also the case with tropine and other bases that have an alkyl group attached to the nitrogen. As indicated by the investigations of Wernicke and Wolffenstein concerning the action of hydrogen peroxide upon N-alkyl piperidine bases, the above conversion of scopoline into oxyscopoline is probably brought about by the mere change of the group >N.CH, into >N CH, BEHAVIOR OF SCOPOLINE TOWARD CHROMIC ACID. By oxidizing tropine with chromic acid, G. Merling † readily obtained the dibasic tropic acid. On account of the close relation which seems to exist between tropine and scopoline, it appeared of interest to study this reaction with the latter base. As a preliminary experiment 5 Gm. scopoline were dissolved in 20 Gm. water, this solution treated with a mixture of 12 Gm. chromic acid, 200 Gm. water and 20 Gm. sulphuric acid, and the liquid † Annal. d. Chem. 216, p. 348. * Ber. d. d. chem. Ges., 31, 1553. so obtained boiled for two hours under a reflux condenser, according to Merling's directions. The change in color of this mixture took place much more slowly than in the case of tropine, which for the sake of comparison was subjected to the same conditions. At the end of two hours a considerable amount of chromic acid remained unchanged, although an evolution of carbon dioxide was already apparent. It could further be shown by an examination of a small portion of the oxidation product, that the same still contained unchanged scopoline. A gold double salt prepared therefrom showed all the properties of scopoline-gold chloride. The rest of the oxidation product was therefore boiled for another hour and the chromic acid which then still remained unchanged finally reduced with sulphurous acid. While tropic acid could readily be obtained from the oxidation product of tropine by following the directions of Merling, it was found impossible to isolate either tropic acid or any related compound from the scopoline oxidation product by employing the same method. I therefore freed this oxidation product from chromium and sulphuric acid by the addition of baryta water, and then changed it into a gold double salt. Upon slow evaporation of the respective solutions and repeated recrystallization of the separated double salts, I finally succeeded in obtaining considerable quantities of two distinct compounds, of which the one (I) had the properties and composition of the gold salt of the unchanged scopoline, while the other (II) corresponded with the gold salt of scopoligenine (norscopoline). Gold Double Salt I consisted of small feather-like crystals, which upon remaining in their mother-liquor changed in a characteristic manner into compact, transparent, yellowish-red crystals. M. p. 220-223° C. 0.240 Gm. of the dried salt yielded 0.095 Gm. Au. Found: Au. 39.58 per cent. Calc. for CHNO3. HCI+AuCl2: 39.75 per cent. Gold Double Salt II appeared in bundles of prismatic crystals, or as fine needles grouped together like crystals of sal ammoniac. The m. p. for both forms was 232-233° C. 1. 0.2206 Gm. contained 0.0903 Gm. Au. 2. 0.2368 Gm. contained 0.0970 Gm. Au. 3. 0.2094 Gm. contained o.0860 Gm. Au. Upon recrystallizing the first portion of the double salt obtained from the above-mentioned oxidation product by fractional precipitation with gold chloride, there resulted a small quantity of a gold salt which differed essentially from scopoline-gold chloride and scopoligenine-gold chloride in appearance as well as in its solubility in water. To obtain somewhat larger quantities of this compound, I repeated the oxidation of scopoline, using 10 Gm. of this base. In this experiment, however, the heating was conducted on a water-bath, and was continued (about 15 hours) until the mixture had assumed a pure green color. Even under these conditions the evolution of a considerable quantity of carbon dioxide could be observed. After removing the chromium with baryta water, the solution was somewhat concentrated and then precipitated with gold chloride. From the first portions of this precipitate it was possible, by repeated recrystallizations, to isolate a gold salt which crystallized in fine, opaque, pale-yellow, and sometimes peculiarly twisted needles. These were only very slightly soluble in cold water; they melted at 220-222° C. 1. 0.164 Gm. contained 0.0736 Gm. Au. 2. 0.195 Gm. contained 0.0879 Gm. Au. 3. 0.274 Gm. contained 0.1232 Gm. Au. Found: Au. 43.78 per cent. 44.87 per cent. 44.97 per cent. In making the above determinations, the gold was first precipitated by hydrogen sulphide from the hot aqueous solutions of the double salts. When the filtrate from the the gold sulphide, after concentration, was again precipitated with gold chloride, there again resulted a difficultly soluble double salt with the same gold content, but otherwise of entirely different properties than the above-described. It crystallized in small, translucent, weakly lustrous needles, which formed stellate, feather-like groups. The m. p. of this salt was 248-250°. Upon analysis the following data were obtained: 1. 0.1434 Gm. contained 0.0645 Gm. Au., and yielded 0.190 Gm. AgCl. 2. 0.2316 Gm. contained 0.1036 Gm. Au. 3. 0.2300 Gm. contained 0.1034 Gm. Au. 4. 0.3074 Gm. contained 0.2390 Gm. Au. 5. 0.1644 Gm. yielded 0.0995 Gm. CO2 and 0.0296 Gm. H2O. 6. 0.1632 Gm. yielded 0.0998 Gm. CO, and 0.0280 Gm. H2O. Au. 44.97 per cent. Found: 44.72 per cent. 16.68 per cent. 41.95 per cent. 45.21 per cent. In the above gold determinations the gold was also precipitated as sulphide. The filtrate freed from hydrogen sulphide again yielded the same gold salt. When the oxidation of scopoline was repeated on the water-bath with 20 Gm. of scopoline, and the oxidation products treated as previously described, the above-mentioned gold double salt, melting at 248-250° C., was directly obtained. The double salt, melting at 220-222° C., which had first resulted when operating upon smaller quantities of scopoline (5 Gm.), did not appear. Platinum Double Salt. The platinum double salt, corresponding to the gold salt of m. p. 248-250° C., crystallized from fairly concentrated solutions in thin, lustrous, quadratic plates, which melted at 207-208° C. 0.1453 Gm. of the dried salt contained 0.0473 Gm. Pt. = 32.49 per cent. From the above analytical data the remarkable fact appears that upon oxidizing scopoline an oxygen-free base is formed, very rich in carbon. This indicates that the hydroxyl group in the molecule of scopoline is not attached at the same point as in the molecule of tropine, as reasoning from analogy had led us to assume. Considered with other investigations which have not been quite concluded, the formation of this oxygen-free base may also indicate the point at which the ether-like oxygen atom is fixed in the molecule. It is possible that the further study of this base, which unfortunately can only be produced in small quantities, may completely clear up the constitution of scopoline and of scopolamine. The product obtained by oxidizing scopoline upon the water-bath contained, besides the above-described oxygen-free base, a large amount of unchanged scopoline; evidently very little scopoligenine had been formed under these conditions. On the other hand, considerable quantities of carbon dioxide and methylamine were formed, which latter was identified by the preparation and analysis of its platinum and gold double salts. Further experiments, the results of which I hope to soon report, will show whether or not, besides carbon dioxide, other nitrogen-free compounds are formed in this oxidation of scopoline. On motion of Mr. Charles Caspari, Jr., the paper was received and referred for publication. Mr. Kremers next presented in abstract the following paper by Dr. E. Schaer, of Strassburg, Germany, prefacing his presentation by the remark that Prof. Schaer's residence in Switzerland for a number of years seemed to have made him, as it were, the successor of Schoenbein in his work : ON THE INFLUENCE OF ALKALINE SUBSTANCES ON BY ED. SCHAER, M. D. The influence exerted by certain alkaline reagents on manifold processes of oxidation has been known for a considerable time. "Oxidations in alkaline solutions" play a not unimportant role, not only in laboratories for organic chemistry, but also in technico-chemical workshops; in dyeworks and in other industries in which chemical methods are employed. In the course of recent years numerous observations and experiments have been made in the Pharmaceutical Institute, in part by myself, in part by my students, all of which lead to the same conclusions, viz., that alkaline substances stimulate oxidation. This fact is true not only of the "strong alkalies" such as potassium and sodium hydroxide and ammonia, but of the weaker alkalies as well. It has been observed even in connection with such substances which are almost or entirely indifferent toward the common indicators. The "activating" influence of certain substances may, therefore, be utilized as a very sensitive indication of their alkaline character. * Inasmuch as several articles bearing on this subject have been published in part in publications not commonly accessible, this communication may serve as a brief survey of the most important data, thus serving likewise as an introduction to others and also as a means of stimulating further observations. The stimulating effect (for which I should like to suggest the phrase "activating influence") manifests itself, according to my observations, in connection with three sets of reactions: 1. In connection with the oxidizing effect produced, certain metallic salts, more particularly by those of the heavy and noble metals. 2. In connection with those oxidation processes which in modern theoretical chemistry are designated "intra-molecular oxidation," also as "inner combustion." Substances of this class are characterized by the fact that the oxygen contained in them, which is but loosely bound, i. e., in *The most important of my contributions in which is treated the influence of alkaline substances on oxidation processes are the following: a. On the oxidizing influence of copper salts.-Archiv der Pharmacie, 239 (1901), 610. b. On the activating influence of reducing agents, colloidal noble metals, and basic substances on oxidizing agents.—Liebig's Annalen der Chemie, 323 (1902), 32. c. New observations on the biuret-reaction and on sugar reactions with cupric oxide in alkaline solutions.-Fresenius Zeitschrift f. analyt. Chemie, 42 (1903), I. d. On the influence of inorganic and organic alkaline substances on the capacity for oxidation of metallic salts.-Verhandlgn. der naturforschenden Ges. in Basel, xvi (1903), 70. e. On the increase in the oxidizing influence of certain metallic salts brought about by alkaline substances, more particularly by plant bases.-Archiv d. Pharm., 241 (1903), 401. f. On the phenomena of spontaneous and inner oxidation.-Verhandlgn. d. Schweizer. naturf. Ges. (Winterthur), 1904. g. On the influence of alkaline substances on processes of spontaneous oxidation.— Archiv der Pharm., 243 (1905), 198. Also: E. Fedler, on the influence of alkaloids on certain oxidation processes.-Archiv d. Pharm., 242 (1904), 680. Extract from inaugural dissertation, Strassburg, 1904, "Beiträge zur Kenntniss der Basicoität der Alkaloide, geprüft an ihren Wirkungen auf gewisse Oxidationsvorgänge." |