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Homologues of Acetyl-acetone: Formation of Ketones of the Acetic Series. By A. COMBES (Compt. rend., 104, 920-921).Acetyl-acetone dissolves sodium with evolution of hydrogen and formation of a solid compound, CHNa(COMe)2, which is soluble in ether and is decomposed by water into acetone and sodium acetate. If this sodium-derivative is heated with ethyl iodide in sealed tubes at 130140°, it yields sodium iodide and monethyl-acetyl-acetone, CHEt(COMe)2, a colourless liquid which boils at 175°, and is only slightly soluble in water. It dissolves with development of heat in a solution of sodium hydrogen sulphite, but no crystallisation takes place until the solution is cooled to a low temperature.

This reaction constitutes a general method for the preparation of the homologues of acetyl-acetone. With amyl iodide, the sodiumderivative yields amyl-acetyl-acetone which boils at 225°.

The second atom of hydrogen in the group CH, can also be displaced by sodium, and the disodium-derivatives react with alkyl iodides. It is thus possible to obtain diketones of the two types,


CH(CnH2n+1)·(COMe), and (COMe), : C< CmH2m+1

All the homologues of acetyl-acetone are decomposed into an acetate and a ketone when treated with an alkali. Ethyl-acetyl-acetone yields the methyl propyl ketone discovered by Friedel, and amyl-acetylacetone yields a liquid which boils at 170°, and is identical with the methyl hexyl ketone described by Béhal. The decomposition of diketones homologous with acetyl-acetone furnishes a new method for the preparation of ketones of the type Me CO CnH2+1. All the stages in the operation give almost theoretical yields. C. H. B.

Fatty Acids occurring in Resin Oil. By J. LwOFF (Ber., 20, 1017-1023). The mixed sodium salts obtained by extracting resin oil with aqueous soda were treated with a concentrated solution of sodium chloride to precipitate such sodium salts as are insoluble in presence of salt; the supernatant liquid was poured off, treated with hydrochloric acid, and distilled. The acids were separated by conversion into amides. Valeric, oenanthylic, nonylic, and undecylic acids. were isolated. The amides of the last two acids melt respectively at 77-78° and 80-81°, and both crystallise in lustrous plates soluble in hot water containing ammonia. N. H. M.

Octyl Mono-, Di-, and Tri-chloracetates. By G. GEHRING (Compt. rend., 104, 1000-1001). The octyl alcohol was obtained by the action of potassium hydroxide on castor-oil, and is therefore the secondary alcohol described by Bouis.

The ethereal salts were obtained by passing hydrogen chloride into a mixture of the alcohol and acid, or, in the case of the dichloracetate, of the alcohol and the potassium salt.

Octyl monochloracetate is a colourless, neutral, very mobile oil with an ethereal odour and a burning taste. It boils at 234°, produces a permanent stain on paper, burns with a green flame, and is insoluble

in water but dissolves in alcohol and ether in all proportions; sp. gr. at 10° 0·9904.

The dichloracetate boils at 244°, and is a neutral, colourless, mobile liquid, lighter than water, and very similar in its properties to the monochloracetate, but its odour and taste are less marked. The trichloracetate boils at about 260°, and is a colourless oil with an ethereal odour. It is lighter than water, and closely resembles the two preceding compounds in its general properties. C. H. B.


Metallic Propionates. By A. RENARD (Compt. rend., 104, 913916).—Aluminium propionate cannot be isolated from its solution, which is decomposed on heating with almost complete precipitation of the basic compound (C,H,O2).OA12. Ammonium propionate, syrupy, noncrystallisable, soluble in water and alcohol. Barium propionate crystallises simultaneously from the same solution in two forms: (a) bulky, transparent prisms, (C2H2O2),Bа + H2O, which become anhydrous at 110°; and (b) brilliant, transparent needles, (C,H,O2), Ba + 6H2O, which lose 3H2O in dry air and become anhydrous at 110°, melt above 300°, and then decompose; insoluble in alcohol; 100 parts of water dissolve 541 of dry salt at 12° and 76 at 100°. cium propionate, (C,H,O2),Ca + H2O, brilliant flattened needles, which become anhydrous at 100° and melt above 300°; insoluble in alcohol; 100 parts of water dissolve 417 parts at 12° and 456 at 100°. Cadmium propionate, non-crystallisable syrup, soluble in all proportions in water and alcohol. Chromic propionate, obtained as the basic salt, (CHO),OCr2, a hard, deep-violet, amorphous mass, by concentrating a solution of chromic hydroxide in propionic acid. Cobalt propionate, (C3H5O2)2Co + 3H2O, forms wine-coloured crystalline crusts, which become anhydrous at 100°, melt at about 250° to an indigo liquid; very soluble in alcohol; 100 parts of water dissolve 35.5 parts at 11°; aqueous solution deep wine-red, becomes blue on heating. Copper propionate, (CH,O,)2Cu + H2O, emerald-green prisms which become anhydrous at 100° and decompose at 110°. The neutral solution, heated for some time at 100°, deposits the pale-blue basic salt, (C,H ̧O2)Сu,CuO + H2O. Ferrous propionate, greenish crystals which very rapidly oxidise. Ferric propionate forms a hard, friable, reddish-brown solid; its aqueous solution decomposes when heated, with precipitation of ferric hydroxide. Lithium propionate, CзН¿O2Li + н2O, forms deliquescent crystals, which become anhydrous in dry air; 100 parts of water dissolve 664 parts of dry salt at 14° and 88.8 parts at 100°; 100 parts of alcohol of 95° dissolve 51 parts at 14° and 63 at its boiling point. Magnesium propionate, (C‚Ĥ¿O2),Mg + H2O, a white powder which becomes anhydrous at 100°, and is very soluble in water and alcohol. Manganese propionate forms a pale rose-coloured, syrupy mass which gradually crystallises; very soluble in water and alcohol. Mercurous propionate, (C2H2O2)2Hg2, obtained by double decomposition, a white crystalline powder which melts at 225° and decomposes; 100 parts of cold water dissolve 14 parts of salt; boiling water decomposes the salt into mercury and mercuric propionate, but the decomposition is prevented by a few drops of propionic acid; the salt is also decomposed by

alcohol. Mercuric propionate, (C,H,O2),Hg, forms needles which melt at 110° to a colourless liquid, and decompose at about 180° with loss of propionic acid and formation of mercurous propionate; 100 parts of water at 15° dissolve 19.2 parts; decomposed by water and by alcohol with separation of mercuric oxide. Nickel propionate, (C,H,O2)2Ni + 2H2O, a pale-green syrup which slowly crystallises in dry air and becomes anhydrous at 100°. Lead propionate, (Č,H2O2)2Pb, forms a thick syrup which very gradually changes to a soft, crystalline mass melting below 100°, and soluble in water and alcohol. If its solution is boiled with lead monoxide and filtered, the filtrate deposits small needles of the basic salt (C,H,O2),Pb,PbO; 100 parts of water dissolve 88 parts of this basic salt at 20° and 6·3 parts at 85°. Potassium propionate, C,H2O2K + H2O, crystallises in soft deliquescent plates which become anhydrous at 120° and melt above 300°; 100 parts of water dissolve 178 parts of dry salt at 16° and 309 parts on boiling; 100 parts of alcohol of 95° dissolve 22.2 at 13° and 264 on boiling. Potassium hydrogen propionate forms deliquescent plates which do not lose propionic acid at 100°. Sodium propionate, C2H2O2Na + H2O, forms a soft, deliquescent, crystalline mass, which becomes anhydrous at 100°; 100 parts of water dissolve 991 parts of dry salt at 15° and 187 parts on boiling; 100 parts of alcohol of 95° dissolve 44 parts at 13° and 84 on boiling; no acid propionate is formed. Strontium propionate, (C3H5O2)Sr + 6H2O, crystallises in prismatic needles, which lose 3 mols. H2O in dry air and melt in their water of crystallisation and become anhydrous at 100°; 100 parts of water dissolve 27 parts of dry salt at 12°; it is insoluble in alcohol. Zinc propionate, (C2H2O2)2Zn + H2O, crystallises in needles which become anhydrous in dry air; 100 parts of water dissolve 32 parts of dry salt at 15°; 100 parts of alcohol dissolve 2·8 parts at 15° and 17-2 parts on boiling. C. H. B.

Chlorinated Derivatives of Crotonic Acid. By J. WISLICENUS (Ber., 20, 1008—1110).—a-ß-Dichlorobutyric acid, C.H.Cl2O2, is prepared by passing a strong current of chlorine through a solution of solid crotonic acid in carbon bisulphide. The solvent is evaporated, the residue freed by filtration from adhering oil, and crystallised several times from a small quantity of ether. It forms large, lustrous, colourless prisms which melt at 62.5-63°.

a-Chlorisocrotonic acid, C,H,CIO2, is formed when a-ß-dichlorobutyric acid is treated with an excess of aqueous soda. When the reaction takes place in a hot solution, a-chlorocrotonic acid is also formed; the two acids can be readily separated as potassium salts; the salt of the new acid being readily soluble in cold alcohol. It crystallises from water in needles melting at 662-66.5°. potassium salt crystallises from alcohol in needles of a slightly silky lustre.

a-Chlorocrotonic acid melts at 99-99.5° (not 97.5°).


When liquid isocrotonic acid is treated with chlorine, a liquid product is formed which contains, however, solid a-B-dichlorobutyric acid. When treated with excess of alkali, a-chlorocrotonic acid (m. p. 99-99.5°) and a-chlorisocrotonic acid are formed.

a-Chlorisopropylene, C,H,Cl, is obtained by heating an aqueous solution of the potassium salt of solid a-B-dichlorobutyric acid. It resembles its isomeride and boils at 33-2-33.5°. Propylaldehyde is formed in the reaction. Ordinary a-chloropropylene can be obtained in like manner from liquid a-B-dichlorobutyric acid. (Compare A. Michael and G. M. Browne (next Abstract.)).

N. H. M.

Isomerism in the Crotonic Acid Series. By A. MICHAEL and G. M. BROWNE (J. pr. Chem. [2], 35, 257-260).-The so-called 6-bromocinnamic acid is not identical with the additive product of hydrobromic acid and phenylpropiolic acid (Abstr., 1886, 702). The B-bromocrotonic acid prepared from a-ß-dibromobutyric acid is similarly not identical with the additive product prepared from tetrolic acid. Pure tetrolic acid when treated with hydrobromic acid at 0° deposits crystals which may be crystallised from light petroleum. It differs from its two isomerides in its melting point, 94.5-95°, and its solubility and crystalline form; the silver salt is amorphous and the barium salt crystallises with 1 mol. of water.

H. B.

Synthesis in the Paraffin Series by Means of Aluminium Chloride. By A. COMBES (Compt. rend., 104, 855-858).—If the compound C12H1O6,AlCl (this vol., p. 127) is added in small portions to well-cooled alcohol, an energetic reaction takes place with evolution of hydrogen chloride, and when the product is poured into water a reddish liquid separates, which is a mixture of ethyl acetate, ethyl acetoacetate, and a colourless liquid which has the composition CH12O4, and boils at 120-125°; vapour-density 5.90. This is ethyl acetoacetylacetate, CH,Ac-CO-CH, COOEt, and the formation of ethyl acetoacetate and ethyl acetate is due to the readiness with which it splits up in presence of alcohol and acetic acid. A solid product is also obtained, which is insoluble in water, but dissolves in warm alcohol, benzene, and light petroleum, and crystallises from these solvents in red prisms melting at 129-130°. It has the composition Al2(CHO), and is formed by the union of 6 mols. of ethyl acetoacetylacetate with 2 atoms of aluminium. It is very stable, and is not attacked by sulphuric or nitric acid in the cold, but its alcoholic solution is decomposed by alkalis with precipitation of the aluminium and formation of a crystalline compound.

When butyric chloride is treated in the same way as acetic chloride (loc. cit.), it yields a similar compound which boils at 216° under a pressure of 14 mm. and rapidly becomes solid. After recrystallisation it has the composition nC.H.O and melts at 107°. It does not volatilise without decomposition, but when its alcoholic solution is treated with alkalis it yields salts of the composition C12H19O,Na, and therefore its formula is C12H8O3. This compound is the anhydride of a diketonic acid, butyro-butyryl-butyric acid, the elimination of water from the molecule taking place in much the same way as in the formation of lactones. C. H. B.

Action of Bromine on Carbamide. By A. SMOLKA (Monatsh. Chem., 8,64-68).-The following experiments were undertaken in the

endeavour to obtain a bromine substitution product by the direct action of bromine on carbamide. When bromine is added drop by drop to a concentrated alcoholic solution of carbamide, the product consists almost entirely of ammonium bromide. Bromine and carbamide heated together in equivalent proportions yielded cyanuric acid, ammonium bromide, and free nitrogen; this forms a very convenient method for the preparation of the first named substance.

When bromine and carbamide are heated together in a sealed tube ammonium bromide and eyamelide are formed. G. H. M.

Antimony Tartrate. By GUNTZ (Compt. rend., 104, 850-852). -When an excess of antimony trioxide is boiled with an aqueous solution of tartaric acid, 1 mol. of the oxide is dissolved for every 5 mols. of acid present, no matter how long ebullition is continued, and this ratio is also independent of the concentration of the solution provided that it be not too dilute, in which case the solubility of antimony oxide in water affects the ratio. The free tartaric acid in the solution is determined by means of standard baryta with phenolphthaleïn as an indicator, and the antimony trioxide is determined by means of potassium permanganate. The solution is evaporated to a syrup, and on cooling deposits almost the whole of the antimony in the form of a crystalline acid tartrate, which is purified by washing with absolute alcohol. The original solution may also be evaporated to complete dryness and the excess of tartaric acid removed by treating the residue with alcohol, when the antimony tartrate is left in crystalline leaflets of the composition C,H,O,,SьО·Õн.

Its heat of formation was determined by dissolving it in hydrofluoric acid, and also dissolving in the same acid a mixture of tartaric acid and antimony oxide in the same proportions.

Sb2O, sol. 2C,H.O, sol. = 2C,H,O,SbOOH sol. + H2O sol. develops -0.5 Cal. × 2.

Sb2O, sol.+2C,H,O,KOH sol. = 2C,H,O,SbOOK sol. + H2O sol. develops -0.85 Cal. × 2.

It is evident that the substitution of antimony oxide for hydrogen. develops practically the same amount of heat whether the substitution takes place in tartaric acid or potassium hydrogen tartrate. Antimony hydrogen tartrate is decomposed by water but dissolves in a solution of tartaric acid. The heat of dissolution of antimony trioxide, Sb2O3, in tartaric acid (5 mols.) is +11.2 Cal.

Berthelot obtained +71 Cal. as the heat of formation of the antimony tartrate by dissolving antimony trichloride in tartaric acid. The author has likewise observed that the heat of formation seems to vary with the method of preparation, and further experiments are being made. C. H. B. Constitution of Pyrotritartaric Acid. By C. PAAL (Ber., 20, 1074-1077). According to Fittig, the constitution of pyrotritartaric acid is best represented by the formula <CH: CMeCOCH2 CH: CMCH COOH, that

is, as an unsaturated ketonic acid and a derivative of pentamethylene. 2 x


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