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formed by the pyrogenic decomposition of amyl alcohol, does not seem to be identical with erythrene bromide, since the former decomposes without volatilising, whilst the latter distils completely although with partial decomposition.

Erythrene from coal-gas combines with hypochlorous acid, forming a compound which is soluble in ether, alcohol, or water.

C. H. B.

Triethyl Carbinol. By S. BARATAEFF and A. SAYTZEFF (J. pr. Chem. [2], 34, 463-467).—Triethyl carbinol is obtained by bringing together diethyl ketone (1 mol.), ethylic iodide (3 mols.), and excess of zinc. At the end of a week, the mass is treated with water, the zinc oxide dissolved in sulphuric acid, and the liquid distilled. A colourless liquid of camphor-like odour boiling at 141-143° (uncorr.) is obtained. Sp. gr. at 20° 0·84016 (water at 20° = 1). The acetate is an oil boiling at 160-163°.

Triethyl carbinol when oxidised with chromic mixture gives diethyl ketone, heptylene, propionic and acetic acids, and carbonic anhydride. The triethyl carbinol obtained as above is identical with that obtained by Nachapetian from zinc ethyl and propionic chloride (this Journal, 1871, 1035).

H. K. T.

Dipropyl Carbinol. By D. USTINOFF and A. SAYTZEFF (J. pr. Chem. [2], 34, 468–472).-Butyrone, propyl iodide, and zinc are allowed to react as in the previous paper. On treating with water and distilling, dipropyl carbinol is obtained as a colourless liquid boiling at 154-155°. Sp. gr. at 20° 082003 (water at 20° = 1). The acetate boils at 170-172°. With chromic mixture, the dipropyl carbinol is oxidised first to butyrone, and then to propionic and butyric acids. H. K. T.

Action of Silver Acetate on Tetrabromodiallyl Carbinol Acetate. By W. DIEFF (J. pr. Chem. [2], 35, 17-21).—Saytzeff obtained (Annalen, 185, 138), by the action of silver acetate on the compound OH CAc(CH2 CHBr·CH,Br)2, a product which he took to be the acetate of an alcohol of the formula

OH CH[CH, CH(OH)·CH2OH]2.

The author repeated the experiment, and determined the number of acetyl-groups by heating the compound with alcoholic potash. The numbers obtained corresponded with the formula of a triacetyl-compound, CHO(OAc)3. This compound was also prepared by heating the alcohol (obtained by saponifying the acetate) with an excess of acetic anhydride at 145° for 12 hours. The sp. gr. of the triacetylcompound at 0° = 118013 (water at 0° 1). When saponified by means of baryta, it yields the compound C,H1O(OH). The latter is a viscous syrup, readily soluble in water and alcohol. It is identical with the compound which Saytzeff (loc. cit.) obtained by saponifying the ether with alcoholic solution of hydrogen chloride.

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N. H. M.

Erythrol. By A. COLSON (Compt. rend., 104, 113-115).-The heat of solution of erythrol at 18° is −5·2 cal., and at 9° −5·12 cal.

The heat of neutralisation is affected by the degree of dilution of the solution. The value obtained for the first equivalent of potash was +0.66 cal., and for the second equivalent +0.44 cal. The thermochemical results are not in accord with the generally accepted symmetrical constitution of erythrol.

When erythrol is treated with phosphoric bromide, it yields a bromhydrin, C.H.Br., which melts at 112°, dissolves in 10 parts of boiling ether, and is identical with the crotonylene tetrabromide described by Henninger. If heated with bromine in sealed tubes at 175°, it yields a mixture of a solid and a liquid product. The solid has the composition C,H,Bre, and crystallises in nacreous plates which melt at 167-169°, and dissolve readily in chloroform, but are only slightly soluble in alcohol or ether; sp. gr. about 3.4.

The liquid compound is an isomeride of the solid product. It dissolves easily in chloroform or ether, but is only slightly soluble in alcohol; sp. gr. about 2.9 at 15°. When heated with dilute potash in sealed tubes at 120-130° for several hours, it yields a potassium salt which resembles potassium hydrogen tartrate in appearance, but the angles of the crystals are different, and the crystals have no action on polarised light. Its solutions give no precipitate with salts of calcium or silver, but a precipitate is formed with salts of lead. This compound is in all probability the potassium salt of erythric acid, and this supposition is confirmed by the weight of lead salt obtained from a given weight of the potassium salt.

It would seem, therefore, that the liquid is the unsymmetrical CBr CHBr CHBr CH,Br, whilst the solid is the symmetrical

CHBr2 CHBr CHBr·CHBr2.

This result requires confirmation, but it is evident that the complete hydrolysis of the bromine-derivatives of crotonylene is possible, since the acid obtained was free from bromine. C. H. B.

Glucose and the Saccharification of Starch. By L. CUISINIER (Chem. Centr., 1886, 614).—The sugar found in the soluble part of barley- or maize-meal consists for the most part of dextrose. If this dextrose is formed by the action of diastase, then the ferment must exert a different action on raw starch from what it does on boiled starch. The dextrose may, on the other hand, be formed by another special ferment present in the living grain. This latter view of the case is, according to the author's experiments, the correct one. The ferment present in ungerminated grain converts starch slowly into dextrose. The dextrose so formed is readily crystallisable on concentrating the liquid, the crystals obtained consisting almost exclusively of fermentable sugar contaminated with not more than 1 to 2 per cent. of dextrin. J. P. L.

Action of Saliva on Starch. By E. BOURQUELOT (Compt. rend., 104, 71–74).—Potato-starch, free from glucose, was heated with water to a definite temperature, cooled down to the ordinary temperature, and then mixed with saliva. When fermentation was complete, the reducing power of the liquid was determined by means of Fehling's

solution. The saliva acts only on the starch which has undergone bydration, and it was found that the hydrating action of water begins at about 53°, and increases somewhat irregularly up to 74°, beyond which point an increased temperature exerts no sensible effect.

In a second series of experiments, the water and saliva were mixed together, heated up to a definite temperature, the starch added, the temperature maintained for about 3 hours, and the reducing power of the liquid was then determined. The results show that saliva acts on starch at a temperature below that at which water alone exerts any hydrating action. Feebly acid or alkaline liquids, or solutions of sodium chloride or phosphate have no action on amylose at temperatures below 53°, and saliva in which the ferment has been destroyed by boiling is scarcely more active. It follows that it is the diastase in the saliva which assists the hydrating action of the water.

At the temperature at which water alone begins to convert starch into a hydrate saccharifiable by saliva at the ordinary temperature, water mixed with saliva has a more energetic action than when water and saliva are allowed to act successively in the way described. The difference diminishes, however, as the temperature approaches 58°, at which point the two actions are equal. At higher temperatures, the action is greater if the water alone is heated, and the saliva is afterwards added to the cooled liquid, than when the saliva and water are heated together, since the high temperature destroys the diastase in the saliva. C. H. B.

Starch Granules. By E. BOURQUELOT (Compt. rend., 104, 177180).- Potato-starch was heated with saliva and water at different temperatures for different periods of time. At temperatures below 57°, the amount of reduction increases with the temperature and also with the time, but is not proportional to the latter. At temperatures above 57°, however, the action continues to increase with the temperature, but attains its maximum in about five hours, and proceeds very little further even if the experiment is prolonged to 30 hours.

The hydrating action of water alone increases with the temperature, and is practically complete after five hours, increasing but little if the experiment is continued for 30 hours. The hydrating action of the water is independent of the mass of the water.

It is a general rule that a reaction effected on a single carbon compound is proportional to, or in direct relation to, the time, especially if the action is of the nature of hydration. The divergence from this rule observed in the case of starch and water indicates that starch granules are composed of a complex mixture of carbohydrates, and not only of one or two compounds (granulose and amylose). Possibly these different compounds are polymerides of one original substance. This view is similar to that held by many physiologists concerning the different layers of cellulose which constitute cellwalls. C. H. B.

Inosite. By MAQUENNE (Compt. rend., 104, 225-227).—Walnut leaves are extracted methodically with about four times their weight of water, and the boiling solution is precipitated first with milk of

lime, then with lead acetate, and finally with basic lead acetate, which forms an insoluble compound with the inosite. The last precipitate is washed with water, decomposed by hydrogen sulphide, and the solution concentrated to a syrup. The boiling liquid is then mixed with 7 or 8 per cent. of concentrated nitric acid, which destroys nearly all the foreign matter without attacking the inosite, and, after cooling, a mixture of 4-5 vols. of alcohol with 1 vol. of ether is gradually added to the nearly colourless liquid. Inosite is thus separated as a colourless flocculent precipitate, which is recrystallised from dilute acetic acid, dissolved in water, again treated with nitric acid, and again precipitated with alcohol and ether. A small quantity of calcium sulphate, which always occurs in the product, is decomposed by adding barium hydroxide, and the barium is removed by means of ammonium carbonate, the product being finally recrystallised from water. The yield is about 2.94 grams per kilo. of leaves.

Anhydrous inosite has the composition C6H12O6, whilst the crystals have the composition C&H2O + 2H2O; they lose all their water at 110°. Inosite does not volatilise without decomposition, but its molecular weight can be determined by Raoult's cryoscopic method, that is, by determining the freezing point of its aqueous solution. The freezing point of a solution of 2.5 grams of inosite in 100 grams of water is 0-29°, whilst the calculated value for C,H12O6 is −0·27°. Inosite is only slightly soluble in cold, but very soluble in warm water. It is insoluble in alcohol, ether, and glacial acetic acid, but dissolves readily in dilute acetic acid, from which it can be easily crystallised. It melts at 217° without carbonisation, and boils with slight decomposition in a vacuum at 319°. When heated in the air, it burns readily. Solutions of inosite are optically inactive, both when freshly prepared and after they have been in contact with Penicillium glaucum for six weeks. Inosite is not attacked by boiling dilute acids or alkalis, does not reduce copper solutions, and is not acted on by ammoniacal silver nitrate alone, but in presence of sodium hydroxide it yields a mirror of metallic silver. It does not combine with sodium hydrogen sulphite, is not reduced by sodium amalgam, and is not sensibly affected by halogens in the cold. When heated with bromine and water at 100°, it yields brown products precipitable by salts of barium and similar to those obtained in Scherer's reaction. These compounds contain no bromine, and are oxidation-products which can be more readily prepared by the action of nitric acid.

No acid containing six carbon-atoms can be obtained from inosite, nor will it split up into oxy-acids of the acetic series. It is neither an aldehyde nor a ketone, and contains neither double bonds nor lateral chains; hence, it can only be a hexhydric hexa-secondary alcohol, with a constitution represented by the symbol

OH·CH<

он,

CH(OH).CH(OH)>CH.OH,
·CH(OH)·CH(OH)

which agrees with its optical inactivity.

C. H. B.

Preparation of Isobutylamines. By H. MALBOT (Compt. rend., 104, 63--65).—When isobutyl chloride is heated with an equivalent

quantity of ammonia dissolved in water or isobutyl alcohol, it yields the three isobutylamines, the tri-isobutylamine being formed in largest proportion. If aqueous ammonia is used, the composition of the product is monisobutylamine, 1 part; di-isobutylamine, 4 parts; tri-isobutylamine, 5 parts. This result differs from that obtained by Reimer (Ber., 3, 756) by acting on isobutyl bromide with ammonia dissolved in ordinary alcohol. C. H. B.

Separation of Mono- and Di-isobutylamines by Means of Ethyl Oxalate. By H. MALBOT (Compt. rend., 104, 228-231; see preceding Abstract).-In the first fraction, which is rich in monisobutylamine, it is necessary to produce the maximum quantity of diisobutyloxamide without neglecting to collect the two oxamates which are also formed. In the second fraction, rich in di-isobutylamine, the bases are converted into oxamates, which are then separated by a method more perfect than distillation.

The operations by which these changes are effected are: (1) Ethyl oxalate is added to the aqueous solution of the bases, and the primary bases are thus converted into oxamides; (2), the mixture of anhydrous bases, poor in primary bases, is poured into ethyl oxalate, and primary and secondary bases are thus converted into oxainates; (3), the tertiary bases are separated by distillation, and the oxamates are saponified by calcium hydroxide at a moderate temperature, the calcium oxamates being separated by crystallisation.

Di-isobutyloxamide forms short, acute lamellæ, which are almost insoluble in boiling water, but crystallise from boiling alcohol in long, brilliant, slender needles which melt at 167°, and sublime slowly at this temperature without decomposition.

Calcium isobutyloxamate is obtained by heating the anhydrous isobutylamine with ethyl oxalate, and then treating the product, which boils at 160°, with calcium hydroxide. It crystallises from alcohol in anhydrous needles.

Calcium di-isobutyloxamate, formed in a similar manner, is separated from the preceding compound by fractional crystallisation, since it is more soluble in alcohol, from which it crystallises in slender, flexible, silky needles.

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C. H. B.

Syntheses of Guanylcarbamide. By E. BAMBERGER (Ber., 20, 68-71).-Guanylcarbamide can be obtained by methods similar to those employed in the synthesis of carbamide, guanidine being substituted for ammonia. Thus, the base is formed when an intimate mixture of guanidine carbonate (1 part) and urethane (2 parts) is heated at 160° until alcohol ceases to distil over, NH, COOEt + (NH2),C:NH NH, CO NH·C(NH)NH2+ EtOH. At the same time, sparingly soluble decomposition products of guanidine, showing properties similar to those of ammeline, ammelide, and melanurenic acid, are formed, with evolution of ammonia; the guanylcarbamide can be separated from these by extracting the melt with water, and converting the base into the copper-derivative. Another synthesis, which for its success depends on the observance of several minute precautions, can be effected by heating at about 180° an intimate mixture of potassium

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