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1024 JAPP AND MELDRUM: CVII1.--Homologues of Anhydracetonebenxil. By FRANCIS R. JAPP, F.R.S., and ANDREW N. MELDRUI, B.Sc. ANHYDRACETONEBENZIL, one of the products of the condensation of benzil with acetone under the influence of potassium hydroxide, was shown by Japp and Lander (Trans., 1897, 71, 123) to be a diphenyk cyclopentenolone of the formula By the condensation of benzil with homologues of acetone of the general formulte CH,R’*CO*CH, and CH,R*CO*CH2R’, Japp and Burton (Trans., 1887, 51,431) prepared various homologues of anhydr- acetonebenzil. The constitution of those members of this class which are formed from symmetrical homologues of acetone follows, as a matter of course, from that of anhydracetonebenzil itself; thus the condensation prodnct of benzil with diethyl ketone (loc.cit., p. 432) is C,H,*C=== CH . b(OH) mc,2>C0. 6 5HOMOLOGUES OF ANHYDRACETONEBENZIL. 1025 150'), if we distinguish the CH group in the pentacarhon ring of anhydracetonebenzil as the U-, and the CH, group as the /3-position (compare Trans,, 1899, 75, 1019). But in the case of the compounds obtained from unsymmetrical homologues of acetone, there are two possibilities; thus, from benzil and methyl ethyl ketone both the a- and the P-methyl derivative may be obtained : C,H *C===-CH 5 1 >CO C,H5*7 =C(CH,) C,H,* C( OH)*CH, and C,H,*C(OH)* CH( CH,) a-Methylanh ydracetonebenzil B-Met11 ylanhydracetonebenzil Japp and Lander (Zoc. cit., p. 129) found that a-derivatives are more stable towards permanganate in the cold than P-derivatives, and iu this way arrived at the conclusion that the monoalkyl derivatives of anhydracetonebenzil obtained by Japp and Burton belonged to the @class.* This conclusion was confirmed by Japp and Findlay, who found that these compounds did not interact with benzaldehyde to yield benzylidene derivatives, whereas anhydracetonebenzil compounds containing the methylene group readily do so.We have now repeated and largely extended Japp and Burton's work. Their method of preparing these compounds (loc. cit., p. 431) con- sisted in warmiqg a mixture of the ketone in question-thus methyl ethyl ketone-and benzil with aqueous potassium hydroxide for some days a t a temperature of 20-25'. This procedure left unchanged a considerable amount of benzil, which had to be removed by washing the product with ether.We find that in this way a soluble isomeride mas removed along with the benzil, and overlooked. By using a slight excess of the ketone and heating to a somewhat higher temperature, me ensure the total conversion of the benzil. The separation of the two isomerides then presents no difficulty. I n the foregoing mode of preparation, the sparingly soluble isomeride generally predominates; but we find that, by allowing the condensa- tion of the ketone with benzil to take place a t the ordinary tempera- ture in a 0.5 per cent. solution 'of potassium hydroxide in absolute alcohol, the more soluble isomeride is generally formed in greater quantity. (m. p. 118"). (m. p. 180'5"). * Although this conclusion happened to be correct, we have since convinced ourselves that, except in the case of acid deriv:itives of anhgdracetonebeuzil, which may be dissolved in a solution of sodium carbonate before applying the periiianganate test, the difference i n the ratc of oxidation is not suficicntly marked to serve as a means of distinguishing with certainty between the two classes. The open-chain condensation compounds of benzil with ketones may, however, be distinguished from anhydracetonebenzil derivatives by the inuch greater ease with which they are attackcd by permanganate.1026 JAYP AND MELDRUM: I n the case of the monoalkyl anhydracetonebenzils, the a-compounds are more soluble, and melt lower, than tho corresponding @corn- pounds.I n the condensation of b e n d with methyl ethyl ketone, there is formed, in addition to a-methylanhydracetonebenzil (m.p. 118') and P-methylanhydracetonebenzil (m. p. 1S0.5'), a third isomeride melting at 157'. Its formation was only once observed in the original conden- sation, but it can be prepared from the P-compound by leaving the latter for a month in contact with cold alcoholic 0.5 per cent. potassium hydroxide, or by boiling it with glacial acetic acid. I n both cases, the transformation is only partial, and, moreover, the resulting cornpound is partially retransformed into P-methylanhydracetonebenzil by allowing it to stand with alcoholic potassium hydroxide in the cold, bo that there is evidently an equilibrium. By heating alone a t 330°, it is totally converted into P-methylanhydracetonebenzil. We regard this compound as desylene-methyl ethyl ketorrze-probably the fumaroid Q6H, qO*CH2*CH3 form, C==Q .In its transformation into P-methyl- anhydracetonebenzil, it would first pass into the maleoid form, which would then undergo internal aldol condensation : I C6H5*C0 H 7sH5 7 >GO C H *C--CH C==C: I p --f C6H,*C(OH)*CH( CH,) 5 1 I C,H,*bO CH,- CH, Maleoid form. 8-Methylanhydracetonebenzil That this compound is not a stereoisomeride of P-methylanhydracet- onebenzil is, we consider, proved by the fact that it is so much more readily attacked by permanganate than the latter compound. The substance is, however, difficult to obtain in quantity, so that we have not been able t o make a detailed study of its reactions, and we there- fore put forward the above formula with reserve. A similar open-chain isomeride of up-dimethylanhydracetonebenzil is described later on.By boiling either a- or P-methylanhydracetonebenzil for a few minutes with fuming hydriodic acid, methyldiphenglcyclopentenone, (m. p. 180"). C,H,*fi*CH( CH3) phenylhydrazone. >CO (m. p. 77-78'), was obtained. It yields a The same migration of the double bonds occurs C,H,* C- CH2 during the reduction as in the formation of diphenylcyclopentenone, C,H,*S*CH, C,H,*C*CH, >CO, from anhydracetonebenzil. The symmetrical con-HOMOLOGUES OF ANHYDRACETONEBENZIL. 1027 stitution of the latter cyclopentenone was proved by Japp and Lander (Trans., 1897, 71, 132) by oxidising it to diphenylmaleic acid. By boiling a-methylanhydracetonebenzil for 5 hours with hydriodic acid and red phosphorus, it mas completely reduced to 1-methyl-2 : 3- C,H5*$2H*CH(CH,) C,H,*CH-CH, >CH2 (m.p. 6 2- 6 3"), already diphenylcyclopentane, obtained by Japp and 1Sluiaray (Trans., -1897, 71, 152), by the reduc- tion of a-anhydracetonebenzillavulic acid, the carboxyl group of the acid being eliminated in the latter case. a-Methylanhydrscetonebenzil, like anhydracetonebenzil itself, readily interacts with benzaldehyde under the influence of alcoholic potassium hydroxide in the cold, yielding a benzylidene derivative. Benxylidene- a-~r~eth~lc~~czzh~drucetonebenxil (m. p. 225") has the constitution C,H,* y: c (CH3 >> co C,H,* C(0H)-C=CH* U,H,' The other a-alkylanhydracetonebenzils yield similar benzylidene derivatives. When P-methylanhydracetonebenzil, on the other hand, is allowed to stand with benzaldehyde and alcoholic potassium hydroxide, there is, at first, apparently no action.After the mixture has stood for a month, however, it is found that a portion of the P-methylanhydr- acetonebenzil has been converted into the open-chain compound desylene-methyl ethyl ketone" (m. p. 157") already referred to, whilst a very small quantity of the benzylidene derivative of a-methylanhydr- acetonebenzil has been formed. This means that, in presence of the potassium hydroxide, a portion of the P-methylanhydracetonebenzil is hydrolysed to benzil and methyl ethyl ketone (the formation of the open-chain compound being an intermediate stage), and that these products of hydrolysis again interact, yielding, in part at least, a-methylanhydracetonebenzil, which then undergoes condensation with the benzaldehyde.a-Methylanhydracetonebenzil and benzil interact, in presence of alcoholic potassium hydroxide, to form a-metl~ylan~~~drucetoned~~enx~C32H2604 (dirnorphous ; silky needles, m. p. 1S5O ; and warty crystals, m. p. 194*), C18H1602 + C14H1002 = C32H26043 which is obtained in the form of the complex potassiun8 salt, C,2H,,04K,~,2H2604,4C~H5~OH. From this salt, the free substance is obtained by treating it with acetic acid. U- RiIetliylanhydracetouedi- * We a t first took this substance for an aldol condensation compound of benz- aldehyde with ~-metl~y~aiihgclmcetonebenzil (see Trans., 1899, 76, 1020, footnote). The difference in percentage composition is but small,1028 JAPP AND MELDRUM: b e n d may be more simply prepared by the action of an alcoholic solution of sodium ethoxide on a mixture of benzil (2 mols.) with methyl ethyl ketone (1 mol.) : C,H5*F0 2c6H5* Go + CH3*CO*C2H5 = C,,H,,O, + H20, the substance being thus obtained in the form of its sodium salt.When a-methplan hydracetonedibenzil is boiled with alcohol containing a few drops of sulphuric acid, it is esterified, yielding the compound C32H25(OC2H5)03 (m. p. 250O). I n yielding salts with caustic alkalis, and in being esterified under the foregoing conditions, a-methylanhydr- acetonedibenzil resembles ethyl anhydrodibenzilacetoacetate (Japp and Lander, Trans., 1896, 69, 736), and differs entirely from the corre- sponding compound from acetone and bend-anhydracetonedibenzil, C3,H2,04-of which it might otherwise appear to be the next higher homologue.By boiling a-metbylanhy dracetonebenzil with sulphuric acid some- what diluted with water, or with glacial acetic acid, a dehydration product, C,6H2s02 (m. p. 230°, with evolution of gas), is formed accord- ing to the equation The molecular weight of the resulting compoundis doubled in order to bring it into line with the corresponding compound, C24H2402, from anhydracetonebenzil (Japp and Lander, Trans., 1897, 71, 131). /3-Methylanhydracetonebenzil is converted into the same dehydration product, C36H2802, by heating it in a sealed tube with anhydrous formic acid ; whereas glacial acetic acid, as already mentioned, transforms it into desylene-methyl ethyl ketone. 2C,,H,,02 - 2H,O = C8sH2s02. EXPERIMENTAL. Condensation of Benail witTi Methyl Ethyl Ketone.>GO, C6H5*F=C(CH3) C,H,*C(OH) *CH2 Preparation of a-Ueth y lanh ydraceionebenxi I , C H *C---CH C,H,*C(OH) CH(CH,) and P-Met~ylanhydracetone6enxil, ' I >GO. -These compounds are formed by the condensation of benzil with methyl ethyl ketone under the influence of potassium hydroxide. With alcoholic potassium hydroxide, the a-compound is almost the sole product ; with aqueous potassium hydroxide, the P-compound slightly predominates. In the preparation of the a-compound, 10 grams of finely powdered benzil, 7 grams of methyl ethyl ketone, and 100 C.C. of alcoholic 0.5HOMOLOGUES O F ANHYDRACETONEBENZIL. 1029 per cent. potassium hydroxide (4 grams KOH to 1 litre of absolute alcohol *) were introduced into a flask which was then corked and, after dissolving the benzil by shaking, allowed to stand.The experiment was so arranged that the liquid nearly filled the flask and that the quantity of alcohol was just sufficient to dissolve the benzil. After standing a t the ordinary temperature for 17 days, the liquid, from which nothing had been deposited, was poured into alarge bulk of water ; this occasioned the separation of an oil, which speedily solidified to a mass of almost white crystals of the a-compound. After a single crystallisation from hot alcohol, the substance was pure. It formed large, flat, lozenge-shaped crystals melting a t 1 1 8 O . It is readily soluble both in alcohol and in ether. Analysis of a-met?~~Zanl~?ldrcccetoneb~n~~Z gave figures agreeing with the formula CI8Hl6O2 : 0,1585 gave 0.4734 CO, and 0-0866 H,O.C = 81.47 ; H = 6.07. 0.1402 ,, 0.4187 CO, ,, 0.0781 H20. C ~ 8 1 . 4 5 ; H=6.19. C,,H,,O, requires C = 81.82 ; H = 6.06 per cent. The yield from the above quantities was 8 grams, and the alcoholic mother liquor gave a small amount-considerably less than a gram- of the isomeric P-methglanhydracetonebenzil already obtained by Japp and Burton, I n order t o prepare p-methylanhydracetonebenzil in quantity, the method employed by Japp and Burton (loc. c k ) was, with slight modi- fications, adopted. Forty grams of benzil, 25 grams of methyl ethyl ketone, and 30 C.C. of aqueous potassium hydroxide of 33.3 per cent. strength were introduced into ti conical flask fitted with a condensing tube, the whole being placed on a metal plate over a water-bath and heated for 9 hours, shaking from time to time. The mixture, which had become brown, was poured into excess of hot water. The soljdi- fied substance was ground, washed with water, and well extracted with cold ether.The residue was dissolved in boiling alcohol; on cooling, prismatic crystals of P-met?~~Zanhydracetoneben~~Z mere deposited, which, after two or three recrystallisations, melted constantly a t is00 (179O, Japp and Burton). The alcoholic mother liquor gave n small quantity of octahedral crystals melting a t 157", of a substance rvhich is isomeric with the two foregoing, and which we regard as desylene- methyl ethyl ketone (u. infra). The ethereal extract gave a consider- able quantity of a-methylanhydracetonebenzil (m.p. 1 18O). I n the foregoing experiment, the quantity of a-compound obtained * Absolute alcohol should be used in these condecsations. I r Methylated spirit 1' (alcohol " denatured " with crude wood spirit ; compare Trans., 1897, 71, 297, footnote) must be avoided, as it contains acetone, which yields condensation cmn- pounds of its own with benzil. VOL. LXXIX. 4 A1030 JAPP AND MELDRUM: was 86 grams, and of j3-compound, 11 grams. Longer heating dimin- ished the proportion of the P-compound, and in addition, the resinous bye-products rendered the substances more difficult to purify. P-Methylanhydracetonebenzil has already been analysed by Japp and Burton. MoZecuZccr Weights of a- and P-MethyZanhydi*acetonebenzil.-The molecular weights of the two compounds were determined by Walker and Lumsden's modification of Landsberger's, ebullioscopic method, using alcohol (constant = 1560) as a solvent.a-Met?$anhydracetonebenzi!. SnBstance. Elevation. Volume. Mol. wt. 0.90s 0.32' 16% C.C. 267. 9 9 0-24 22-4 )) 263. C1,H,,O2 = 264. P- Methy ZanhydracetonebenxiZ. O*S96 0-292O 15.6 C.C. 308. 9 9 0.210 22.2 ,) 300. C1,H160, = 264. The two substances are therefore isomeric. -Five grams of a-methylanhydracetonebenzil, 2.5 grams of benzalde- hyde, and 65 C.C. of alcoholic potassium hydroxide (0.5 per cent.) were mixed, shaken until all had dissolved, and allowed to stand. Over- night, tufts of needle-shaped crystals had formed ; after 4 days they were separated and recrystallised from hot glacial acetic acid, from which the substance was deposited in colourless, slender, rectangular prisms melting a t 2 2 5 O .(Yield 3.6 grams.) 0.1608 gave 0.5018 CO, and 0.0839 H20. C,,H,,O, requires C = 85.23 ; H = 5.68 per cent. /I-Methylanhydracetonebenzil, when subjected to the above treatment Its behaviour on long standing Conversion of P-Methy ZanThydracet one benxi I into Desy Zene-methyl Ethy l C=85*11; H=5*80. for the same time, is quite unchanged. with the mixture is mentioned in the introduction. Ketone, '' ' *ciCH*c0*C2H5,-T~e I best mode of effecting this trans- C,H,* CO formation- is- by boiling P-methylanhydracetonebenzil with four times its weight of glacial acetic acid for 4 hours. The solution, on cooling, deposits needles or prisms of unchanged substance; and from theHOMOLOGUES OF ANHYDRACETONEBENZIL.1031 mother liquor, octahedral crystals of the open-chain compound, melt - ing a t 157', may be obtained. The same compound is also slowly formed when finely powdered P-methylanhydracetonebenzil is allowed to stand for a month or more with alcoholic potassium hydroxide (0.5 KOH per cent.) insufficient to dissolve it. The transformation is incomplete, as the reaction is reversible (see introduction). The formation of the same compound was also observed in the pre- paration of P-methylanhydracetonebenzil (v. supra). Analysis of the octahedral crystals (m. p. 157') showed that the substance, which we regard as desylene-methyl ethyZ ketone, is isomeric with a- and P-methylanhydracetonebenzil. 0.1485 gave 0.4431 CO, and 0,0798 H,O.C = 81.36 ; H = 5.97. 0.1629 ,, 0.4862 CO, ,, 0.0903 H,O. C=81*39 ; H=6*16. C18Hl,0, requires C = 81.82 ; H = 6.06 per cent. The reason for regarding this compound as structurally different from the methylanhydracetonebenzils is that it is much more readily attacked by permanganate. A small quantity of the compound was heated in an exhausted tube for a short time at 330'. There was no sign of decomposition, and the melted substance began to distil and collect in the cooler part of the tube. On crystallising the product from alcohol, it was found that i t had been re-converted into P-methylanhydracetonebenzil (m. p. 180'). a-Methylanhydracetonebenzil is quite unchanged by contact with alcoholic potassium hydroxide of the above strength. Boiling with glacial acetic acid dehydrates it, yielding the compound, C.1602802, melt- ing a t 230' (v.infrcc). Action of Dehydrating Agents on a- and P-Met~yl~nhydracetone- bend.-One gram of a-methylanhydracetonebenzil was boiled for half- an-hour with 5 C.C. of sulphuric acid diluted with 10 C.C. of water, employing a reflux condenser. From the product, which was very dark coloured, crystals melting a t 230' were obtained. The following method yields the substance in a purer state. One gram of a-methylanhydracetonebenzil was boiled with 4 grams of glacial acetic acid for 4 hours. On cooling, the liquid deposited a crystalline compound which proved to be identical with that obtained by the action of hot dilute sulphuric acid. Recrystallised, first from glacial acetic acid and afterwards from amyl alcohol, it formed minute, very lustrous, oblique prisms or plates, melting, when rapidly heated, a t 230°, with evolution of gas-doubtless carbon monoxide, to judge from the analogy of the corresponding compound, C,,H,,O,, obtained from nnhydracetonebenzil (Japp and Burton, Trans., 1887, 51, 426).It is sparingly soluble in solvents of low boiling point, 4 A 21032 JAPP AND MELDRUM: Analysis gave figures agreeing with those required for the Formula 0.1321 gave 0.4240 CO, and 0.0734 H,O. P-Methylanhydracetonebenzil is not altered by boiling with sulphuric acid of the foregoing strength, whilst a stronger acid chars it. Boil- ing it with acetic acid, and even heating with the acid in a sealed tube at 130°, gave only desylene-methyl ethyl ketone, Heating with formic acid, however, converts it into the compound C3,H2,0,. Four grams of P-methglanhydracetonebenzil and 16 grams of concentrated formic acid were heated in a sealed tube a t 130' for 4 hours.The products were a pasty solid and a violet coloured liquid. The solid was dissolved in benzene, and light petroleum was added, which precipitated resinous matter. The filtrate yielded lustrous crystals of the compound C3,H,,02, which, after recrystallisation from acetic acid, melted at 230' with evolution of gas. a- and P-Methylanhydracetonebenzil thus yield the same compound, C36H2802, by elimination of the elements of water. The reason for doubling the formula of this substance is given in the introduction. Reduction of a- and ~-Me~hytanhyd~acetone6enxiZ with Hydriodic Acid : C36H2802D C = 87-54 ; H = 6.18.C36H2802 requires C = 87.82 ; H = 5.69 per cent. Formation of Methyldiphen y Zc yclopen tenone, C6H5*~*CH(GH3)>co, C6H,*-CH2 1-Methyl-2 : 3-diphenylcyclopentane, C6H5* 9H*cH(cH3)>CH2.-Ten grams of a-methylanhydracetonebenzil were boiled with excess of fuming C,H,*CH-CH, hydriodic acid (sp. gr. 1.9) for 5 minutes. Excess of water was added, and the solid substance, separated by filtration, was dissolved in ether. The ethereal solution was shake3 with dilute sulphurous acid, then with a solution of sodium carbonate, and dried with calcium chloride. On spontaneous evaporation, it gave crystals which, after repeated recrystal- lisation from light petroleum, were obtained in the form of faint yellow, oblique, flat prisms or plates melting constantIy at 77-78O.In another experiment, the residue which remained after expelling the ether was distilled under reduced pressure. The crude product passed over a t about 200' under a pressure of 12 mm. This procedure considerably facilitated the purification of the substance, but was attended with loss. The compound was finally crystallised from light petroleum. Analysis gave figures agreeing with those required for a rnethyldi- phenytc yclopentenone, C18H160. 0.1936 gave 0.6179 CO, and 0.1146 H,O. It melted, as above, at 77-78". C=87.04; H=6.58. 0.1730 ,, 0.5524 CO, ,, 0.1013 H,O. C = 87.08 ; H = 6-50. C,,H1,O requires C = S7*10 ; H = 6.45 per cent,HOMOLOGUES OF ANHYDRACETONEBEJSZIL. 1033 /3-Metbylanhydracetonebenzil was then reduced in precisely the same way with hydriodic acid.It yielded the same methyldiphenyl- cyclopentenone melting a t 77-78'. A supersaturated solution of the compound thus prepared inst,antly crystallised on adding a little of the crystalline compound obtained from a-methylanhydracetonebenzil. Met h yldipheny lcy clopen t enone forms a pheny Zhydraxone, I n preparing this compound) 1 gram of rnethyldiphenylcyclopentenone was heated with 1 gram of phenylhydrazine and about 6 C.C. of alcohol in a sealed tube for 5 hours at looo. Addition of dilute acetic acid and, subsequently, of water, caused the separation of an oil; this was dissolved in warm alcohol. The solution deposited clusters of minute, yellow prisms melting with decomposition a t from 145' to 152'accord- ing to the rate of heating.It decomposes on recrystallisation. Analysis gave figures agreeing with those required for the foregoing phert ylh ydraxone. 0-1181 gave 8.5 C.C. moist nitrogen at 13.5Oand 757 mm. N=8*46. C,,H,,N2 requires N = 8.28 per cent. In order to carry the reduction further than the formation of methyldiphenylcyclopentenone, and to obtain, if possible, the corre- sponding cyclopentane derivative, 10 grams of a-methylanhydracetone- benzil were boiled with 150 grams of hydriodic acid (sp. gr. 1.7) and 20 grams of red phosphorus for 5 hours. The product was worked up as described in the foregoing reduction experiments, removing iodine and then distilling under reduced pressure. A large fraction passed over between 160' and 200' under 20 mm.pressure ; on standing, it solidified. On dissolving it in ether and adding methyl alcohol, tufts of colourless, slender needles separated ; after recrystallising twice from the same solvents, they melted constantly at 62-63O. The sub- stance was identical with the 1 methyl-2 : 3-dip~enylcyclopenta~ ob- tained by Japp and Murray (Trans., 1897, 71, 153) by the reduction of a-anhyclrobenzill~vulic acid. A specimen prepared in the latter way a t once started the crystallisation of a supersaturated solution of the present compound. 0.1791 gave 05990 CO, and 0.1380 H,O. Condensation of u-Metl~ylanl~yd~cccetonebenxiZ with Bend ; Formation of a-MethyZan~~ydracetonedibenxiE, C,,HZ6O,.-The fact that anhydr- acetonebenzil interacts with b e n d in presence of dilute alcoholic potassium hydroxide to form an aldol condensation compound, anhydr- C=91*20 ; H=8.56, C1,H,, requires C = 91.52 ; H = 8.48 per cent.1034 JAPP AND MELDRUM : acetonedibenzil (Japp and Findlay, Trans., 1899, 75, l025), led us to try whether a-methylanhydracetonebenzil would exhibit an analogous behaviour.In our first experiment, we used the very dilute alcoholic potassium hydroxide which had proved efficacious in the previous condensations. The reaction took place ; but as the product proved to be a potassium salt, and as there was not sufficient potassium hydroxide present to form this salt with the whole of the other interacting substances, we repeated the experiment, using a stronger solution of the hydroxide, and obtained a much better result.3.3 grams of a-methylanhydracetonebenzil and 2.5 grams of b e n d were dissolved in 32 C.C. of alcoholic potassium hydroxide (2 grams of KOH to 100 C.C. of absolute alcohol). The solution was filtered into a small flask, which was corked up and the whole allowed to stand. (As the potassium salt cannot be recrystallised without decomposing it, it is necessary to obtain it pure at once.) After 4 days, there was a deposit of large, well-developed crystals ; these were separated, washed with cold alcohol, and air-dried by brief exposure on filter-paper. They effloresce on standing. The compound is a potassium salt of a-methyhnhydvacetonedibenzil, C3,H2,0,, and has the complex formula C3,H,50,K,C32H,,04,4C2H5* OH. Like the sodium salt of ethyl anhydrodibenzilacetoacetate (Japp and Lander, Trans., 1896, 69, 736), i t is readily soluble in benzene and is totally decomposed by boiling with alcohol. The potassium was determined in the ordinary way as sulphate ; the a-methylanhydracetonedibenzil by shaking a benzene solution of the salt with dilute hydrochloric acid, washing with water, and afterwards freeing from moisture and benzene, a process which could give only an approximate result ; and the alcohol of crystallisation by leaving the substance in a vacuum desiccator over sulphuric acid for 6 weeks, heating being inadmissible, The potassium determinations were made with different preparations.0-5784 gave 0.0414 K,SO,. K= 3.21. 0.7854 ,, 0.0566 K,SO,. K = 3.23. 2.0983 ,, 1.737 C32K2604. C3,H2,O,= 82-97. 1.3482 lost, on drying, 0.2070, C,H,* O H = 15.35.C3,H2,0,K,C,,~,,0,,4~2~G0 requires K = 3.33 ; C,,H,,O, = 81.02 ; C,H,O = 15.72 per cent. The sodium salt, which was not annlysed, was obtained direct from benzil and methyl ethyl ketone. Ten grams of benzil and 6.8 grams of methyl ethyl ketone were added to 200 C.C. of absolute alcohol in which 4.4 grams of sodium had previously been dissolved. There was a slight rise of temperature and the benzil went into solution. AfterHOMOLOGUES OF ANEYDRACETONEBENZIL. 1035 standing overnight in a corked flask, the liquid had deposited a large quantity of needle-shaped crystals. The substance was worked up for a-methylanhydracetonedibenzil after standing for 3 days. It mas identical with a sodium salt which we obtained by condensing a-methyl- anhydracetonebenzil with benzil by means of an alcoholic solution of sodium ethoxide.In order to obtain free a-methylanhydracetonedibenzil, either the potassium or the sodium salt, prepared as already described, is washed with cold alcohol and dissolved in benzene in the cold. By adding glacial acetic acid until the solution has an acid reaction and then shaking with water, the alkali metal is removed. The a-methyl- anhydracetonedibenzil soon begins to separate in a crystalline f orm from the benzene solution ; it is purified by recrystallisation from boil- ing alcohol. Two kinds of crystals are obtained : from the hot alcoholic solution, small? hard warty crystals melting a t 194O; from the cold solution, silky needles melting a t 185'. The two forms may be readily changed one into the other, and neither contains solvent of crystallisa- tion.The same two forms are deposited from a benzene solution. On analysis, the substance gave figures agreeing with those required for the formula of a-met?~~k~i.L?~ydi.aceto~aedibenzil, C,,H,,O,. Analysis I was made with the needles ; analysis I1 with the warty crystals. 0.1433 gave 0,4396 CO, and 0,0748 H,O. C = 80.57 ; H = 5.58. 0.1472 ), 0.4352 CO, ,? 0.0750 H,O. C=S0*63 ; H=5*66. C,2H,604 requires C = 81.01 ; H = 5.48 per cent. Like its analogue, ethyl anhydrodibenzilacetoacetate, it is difficult to burn. As the composition of the potassium salt of a-methylanhydracetone- dibenzil might be taken as pointing to a molecular weight twice as great as that represented by the formula C32H2604, an ebullioscopic determination of the molecular weight was made by the method already referred to, using alcohol (constant = 1560) as a solvent.a-Metl~ybnhydrc~ceto.lzedibenxil. Subs tinice. Elevation. Voliuiie. 3101. wt. 0-613 0.13" 17.5 C.C. 420 ?) 0.10 22.5 425 C,,H2,04 = 474. This result decides in favour of the lower molecular weight. Ethylcction of a-Met~ykanh?/d.rwacetonediben;zil.--The fact that a hydro- gen atom in ethyl anhydrodibenzilacetoacetate may be replaced by ethyl by boiling the compound with alcohol containing a few drops of1036 JAPP AND MELDRUM: sulphuric acid (Japp and Lander, Trans., 1896, 69, '738) led us to try the same experiment with a-methylanhydracetonedibenzil. Five grams of a-methylan hydracetonedibenzil, 100 C.C.of absolute alcohol, and 5 drops of concentrated sulphuric acid mere boiled, using a reflux condenser, At first everything dissolved; but in a short time a separation of small crystals commenced, the amount of which gradu- ally increased, After 3 hours, the operation was interupted; the crystals were separated and washed with alcohol. They formed very sparingly soluble, colourless, short needles, melting a t 250'. Analysis showed that an ethyl derivative, C,2H,,(OC2HB)0,, had been formed. 0.1643 gave 0.4883 CO, and 0.0895 H,@. C = 81-09 ; H = 6.05. CsaH3,0, requires C = S1.27 ; N = 5.98 per cent, Condensation of Bend with othev Ketones. The condensations remaining to be described were all carried out by the methods already given for the preparation of a- and P-methyl- anhydracetonebenzil, the condensing agent being either alcoholic 0.5 per cent.potassium hydroxide (4 grams KOH to 1 litre of absolute alcohol) in the cold, or aqueous 33.3 per cent, potassium hydroxide a t a temperature somewhat under 100' (see preparation Gf P-methyl- anhydracetonebenzil). Where two isomeric condensation compounds are formed, the former method generally gives, as already mentioned, the better yield of the compound of lower melting point. The aepara- tion of the two isomerides was effected by fractional crystallisation from alcohol, occasionally preceded by extraction of the more soluble isomeride with ether. C,H,*y: C(CH,) CO- C,H, a-Besylene-ethyl Ethyl hTetone, .co , aitd aP-Di- 0 5 C(CH3)>C0.-In the ex- C,H,*Y- C,H,*C(OH)*CH( CH,) meth?/l~nhydracetone6en~~l, periment in which alcoholic potassium hydroxido was used, the pro- portions mere : benzil, 10 grams ; diethyl ketone, 7.5 grams j alcoholic potassium hydroxide (0.5 per cent.), 100 c.c., the whole being allowed to stand for a month. Crystals of up-dimethylanhydracetonebenzil separated, but a great part remained in the mother liquor along with the more soluble a-desylene-ethyl ethyl ketone. The product was pre- cipitated with water, and the crystalline precipitate resolved into its two constituents as already described in the precipitation of a-methyl- anh y dracetonebenzil.In the experiment with aqueous potassium hydroxide, the following proportions were used : benzil, 40 grams ; diethyl ketone, 30 grams ;HOMOLOGUES OF ANHYDRACETONEBENZIL.1037 aqueous potassium hydroxide (33.3 per cent,), 30 C.C. Time of heating 24 hours. (For mode of heating and of working up, see preparation of P-methylanhydracetonebenzil.) The products were the same as in the previous experiment, but the proportion of ap-dimethylanhydr- acetonebenzil was greater. The yield of this compound was 27 grams. aP-Dimetl~?/kLnh?/clrncetonebenziZ crystallises from alcohol in colour- less, rhomboidal plates or prisms, melting a t 150°, as described by Japp and Burton jloc. cit.), by whom it was prepared and analysed. a-Desylene-ethyl ethyl ketone is deposited from alcohol in large, oblique, four-sided prisms melting a t 128". Analysis showed that it was isomeric with the preceding compound. 0,1649 gave 0.4943 CO, and 0.0967 H,O.c! = 81.75 ; H = 6.52. 0,1670 ,, 0.5012 CO, ,, 0.0988 H,O. C=81.85 ; H=6*57. U,,H,,O, requires C = S2.01 ; H = 6-48 per cent. a-Desylene-ethyl ethyl ketone is much more readily attacked by per- manganate than a/?-dimethylanhydracetonebenzil, indicating that it is structurally different from, not merely stereoisomeric with, the latter compound. It is probably fumaroid u-desylene-ethyl ethyl ketone, as the maleoid form might be expected to undergo internal aldol conden- sation to up-dimethylanh ydracetonebenzil under the influence of potass- ium hydroxide. This change, however, takes place under the influence of heat. A small quantity of a-desylene-ethyl ethyl ketone was heated in an atmosphere of carbon dioxide at 300-320' for 10 minutes. The fused mass, which had turned light brown, was dissolved in alcohol; on seeding the solution with a trace of up-dimethylanhydracetonebenzil, it began to crystallise and deposited the characteristic rhomboidal plates of that substance, melting a t 149' (m.p. 150'). The trans- formation occurs as follows : C,H,.$X C(CH,)* CO* CH,*CH, - C6H5*Y= C(CH,)>CO C,H,*CO C,H,* C( OH)*CH(CH,) a-Desylene-ethyl ethyl ketone a~-Diniethylanhpdrace tonebenzil (m. p. 128"). (m. p. 150"). The former compound t,hus corresponds with desylene-methyl ethyl ketone, which under the influence of heat is converted into P-methyl- anhydracetonebenzil (u. supm). It may be noted that the transformation of a-desylene-ethyl ethyl ketone into up-dimethylanhydracetonebenzil does not take place when the substance is heated in a vacuum, as under these circumstances it distils without.change. the method with alcoholic potassium hydroxide mas employed. The1038 JAPP AND MELDRUM : proportions mere : b e n d , 10 grams ; methyl isopropyl ketone, 7.5 grams; alcoholic potassium hydroxide (0.5 per cent.), 125 C.C. The reaction was allowed to go on a t the ordinary temperature, Crystals of the new compound separated within a day. After standing for three days, the product was worked up in the usual may. I t crystallised from alcohol in clusters of prisms, with pyramidal ends, or in plates, melting at 181". Only this one substance was formed in the reaction. Analysis gave figures agreeing with the formula of PP-dinzetlqZ- ccnhydracetonebenxil. 0.1789 gave 0.5358 CO, and 0.1059 H,O.C = Sl.6S ; H = 6.58. 0.1326 ,, 0.3968 CO, ,, O*OSlO H,O. C=81*62; H=6*SO. C,,H,,O, requires C = 82.01 ; H = 6.48 per cent. That the compound is not an open-chain diketone follows from its That it is PP-dimethylanhydracetonebenzil is This will be high melting point." shown by the product which it yields on oxidation. described in a subsequent paper. C,Hb*Y=C(C H ) C,H,-C(0H) CH, a-EtjL?llunhyd.r.ucetonebenxiZ, >CO, and P-Ethyl- - ~~Ayd~acetone bend, CtiH,-~ C H > ~ ~ . - Forty grams of C,H5*C( OH)*CH( C,H,) b e n d , 30 grams of methyl n-propyl ketone, and 30 C.C. of aqueous 33.3 per cent. potassium hydroxide were heated for 16 hours in the way already described. The product, precipitated with water, mashed with ether, and recrystallised from alcohol, formed minute needles melting at 156", and was iden tical with the /3-etl.yEccnhydracetonebenxiZ pre- pared and analysed by Japp and Burton (Zoc. cit.).The ethereal extract gave a more soluble substance which crystallised from alcohol in large prisms, sometimes obliquely truncated, sometimes with pyramidal ends, melting at 114". This proved to be a-ethylanhydr- acetonebenxi 1. I n a second experiment, 10 grams of benzil, 7.5 grams of methyl m-propyl ketone, and 125 C.C. of alcoholic potassium hydroxide (0.5 per cent.) were mixed and allowed to stand at the ordinary temperature for a month, although a shorter time would doubtless have sufficed. The solution had turned brown. The same products were obtained as in the previous experiment, but the yield of the a-compound was better.Analysis of a-ethglanhydracetonebenzil (m. p. 114') gave figures agreeing with those required for the formula C,,H,,O,. C,H,*C:CH*CO*C(CH,), * Thus a-beuzoyl-P-trimethacetylstyrene, , from b e n d C,H;&O and niethyl tcrt. bntyl ketone (to be described in a later communication), melts as low as 115".HOMOLOGWES OB ANHYDRACETONEBENZIL. 1039 0.1756 gave 0.5276 CO, and 0.1036 H,O. C = 81.93 ; H = 6.55. 0.1644 ,, 0,4934 GO, ,, 0,0974 H,O. C=81°S5 ; H=6*58. C,,H,,O, requires C = 52.01 ; H = 6.48 per cent. -One gram of a-ethylanhydracetonebenzil (m. p. 1 la0), 0.5 gramof benz- aldehyde, and 12 C.C. of alcoholic potassium hydroxide (0.5 per cent.) were allowed to stand in a corked test-tube. As after 5 days nothing had separated, crystallisation was started by rubbing with a glass rod.The substance formed colourless needles, On heating, it showed signs of melting at 162-166', but did not entirely melt until 17s' was reached. 0.1748 gave 0.5437 CO, and 0-0961 H,O. C= S4.84 ; H= 6.10. CZ6H2,O2 requires C = 85.24 ; H = 6.01 per cent. P-Ethylanhydracetonebenzil, treated in the same manner, showed no sign of interacting with benzaldehyde. - C,H,* F=- -y(CH3)>C0.-The CcH, * C( OH) C (CHJ, a/3/3- Trimethylanhgdracetone benzil, condensation of benzil with ethyl isopropyl ketone did not take place readily. The best result, although far from a satisfactory one, was obtained by employing as a condensing agent a solution of sodium ethoxide in absolute alcohol. Ten grams of benzil, 6 grams of ethyl isopropyl ketone, and 100 c.c of absolute alcohol, in which 1.6 grams of sodium had previously been dissolved, were mixed and allowed to stand in a corked flask a t the ordinary temperature for 2 months.A shorter time would probably have sufficed. The liquid turned dark, and there was a slight separa- tion of crystals. Water was added, the precipitated substance was washed with ether to remove benzil, and the residue was recrystallised from alcohol. From hot solutions it was deposited in colourless, prismatic needles, by spontaneous evaporation in prisms, melting at 131'. The yield was less than a gram. Analysis gave figures agreeing with the formula C,,H,,02. 0.1566 gave 0.4721 CO, and 0-0993 H,O. C=82.21 ; H=7*04. 0.1721 ,, 0,5171 CO, ,, 0.1091 H,O. C=Sl.94 ; H=7*04. C,,H,,O, requires C = 82.19 ; H = 6.85 per cent.The relatively low melting point might suggest that this is an open- chain compound. We therefore heated the substance for 10 minutes at 300-320' in an atmosphere of carbon dioxide, but, beyond vola- tilising and condensing again in slender needles, it underwent no change. We must therefore assume that it is, as above formulated,1040 JAPP AND MELDRUM: aPP-frimet~yZani~yd1.cccetonebenx~1, since all the open-chain compounds formed in these condensations are converted on heating into the isomeric closed chain derivatives. The question could be finally settled only by a study of the reactions of the compound, but the dificulty of obtaining the necessary ethyl isopropyl ketone, and the smallness of the yield of the condensation product, make this for the present impossible.C6H5*FC(C H ) a-n-Propy~~niLydrucetone b e n d , ' >GO, and P-n-Pro- C,H,*C(OH)*CH, ~. PyZc~nrTLydr~ceto~~e~enziZ, C6H5*y CH>CO.-In the first experiment, 40 grams of benzil, 34 grams of methyl n-butyl ketone, c6H5* C(OH) *CH(C,H7) and 30 C.C. of 33.3 per cent. aqueous potassium hydroxide were heated for 34 hours. The process was carried out as in the preparation of P-methylanhydracetonebenzil. I n working up the product, the ethereal extract gave a substance which was deposited from ether in large, flat, obliquely truncated prisms, and from alcohol in six-sided plates, melt- ing a t 89'. This proved to be a-n-~opylanrTLydl.acetonebenzil. The sparingly soluble residue, recrystallised from alcohol, was deposited in clusters of slender prisms melting at 152O.This was P-n-propyZanhydr- acetonebenxil. It formed the chieF product. The yield of purified P-compound was 12.5 grams, In a second experiment, a mixture of 10 grams of benzil, 8.5 grams of methyl n-butyl ketone, and 125 C.C. of alcoholic potassium hydr- oxide (0.5 per cent.) was allowed to stand in a corked flask a t the ordinary temperature for a month. The products were the same as in the former case, but the yield of a-n-propylanhydracetonebenzil was better. Analysis of a-n-propylanhydracetonebenzil (m. p. 89') : 0.1783 gave 0.5372 CO, and 0.1077 H,O. C = 82-19 ; H= 6.73. 0.1813 ,, 0.5440 CO, ,, 0.1162 H,O. C = 81-83 ; H = 7.12. C,,H,,O, requires C = 82.19 ; H = 6-85 per cent. Analysis of P-n-propylanhydracetonebenzil (m.p. 152') : 0.1836 gave 0.5530 CO, and 0.1121 H,O. C = S2.13 ; H= 6.78. 0.1850 ,, 0.5570 CO, ,, 0.1151 H,O. C=S2.12; H=6.90. C,,H,,O, requires C = 88.19 ; H = 6.85 per cent. Benx y Zidene- a-n-pop ylarh ydracet onehenxi I, C6H50~:C(C3H?)>C0 C,H5* c( OH) -c=c13[*C6H5 -The condensation of u-n-propylanhydracetonebenzil with benzaldehyde was carried out as in the case of the other a-compounds, the reaction taking place in this case also in the cold. The benzylidene derivative was deposited from its hot alcoholic solution in clusters of small laminae melting at 166O.HOMOLOGUES OF ANHYDRACETONEBENZIL. 1041 0.1591 gave 0.4970 CO, and 0.0930 H,O. C,7H,,0, requires C = 85.26 j H = 6-32 per cent. P-n-Propylanhydracetonebenzil did not interact with benzaldehyde.C= 85.19 ; H= 6.49. C,H,*C=-C(C H ) a~-DiethyZccnh~/clrcccetonebenziZ, C,H,. &OH). CH(C ) >CO.-When 2 5 benzil and dipropyl ketone were heated with aqueous potassium hydr- oxide, no condensation took place. The action of alcoholic potassium hydroxide in the cold, however, gave the desired result. A mixture of 10 grams of benzil, 10 grams of dipropyl ketone, and 125 C.C. of alcoholic potassium hydroxide (0.5 per cent.) was allowed to stand in a corked flask a t the ordinary temperature for a month. On pouring the product into water, an oil separated which speedily became crystalline. By recrystallisation from alcohol, only one pro- duct could be obtained : plates of rhombic outline, striated parallel to the shorter diagonal, melting at 113-114'.It was not changed by heating for 10 minutes at 300--320' in an atmosphere of carbon dioxide, thus showing that it is not an open-chain compound. Analysis gave figures agreeing with those required for the formula of diethylanhyd~acetonebenzil. 0.1453 gave 0,4379 CO, and 0.0943 H,O. C = 82.19 ; H = 7.21. 0.2047 ,, 0,6180 CO, ,, 0.1328 H,O, C=82.33 ; H=7*20. C21H2202 requires C = 82.35 ; H = 7.19 per cent. C H *C-C(C5H11) a-n-ArnytccnhydrucetonebensiZ, C6H6*C(OH)* I- CH, >CO, and P-n-anzyl- . C,H,*Y--- -- anhydracetonebenxi~, C,H,*C(OH)*CH(C,H,,) CH>CO.-Forty grams of benzil, 44 grams of methyl n-hexyl ketone, and 30 C.C. of 33.3 per cent. aqueous potassium hydroxide were heated for 15 hours as described under the preparation of P-methylanhydracetonebenzil, the Product being afterwards worked up in the usual way. Only P-umylanhydracetone- benxiZ-slender, silky needles melting a t 150*5O, described and analysed by Japp and Burton-was obtained. In a second experiment, a mixture of 10 grams of benzil, 11 grams of methyl n-hexyl ketone, and 125 C.C. of alcoholic potassium hydr- oxide (0.5 per cent.) was allowed to stand in a corked flask for a month. On pouring into water, the product which separated was partly crvstalline, partly oily. The solid portion, after crystallisation from alcohol, yielded needles of P-amylanhydracetonebenzil melting at 150.5'. The oil, on long standing, also gave crystals-large, six-sided plates-which after recrystallising twice from light petroleum melted constantly at 57O, and proved to be the isomeric a-amykanhydvacetone- benzil. The yield of the latter compound is fairly good.1042 BONE AND JERDAN: THE DIRECT UNION OF Analysis of a-amylanhydracetonebenzil (m. p. 57O) : 0.1763 gave 0,5338 CO, and 0.1210 H,O. C = 82.56 ; H = 7.63. 0.1678 ,, 0.5067 CO, ,, 0.1142 H,O. C = S2.35 ; H = 7.56. C,,H,,O, requires C = 82.50 ; H = 7.50 per cent. Benxyliclene-a-amy Zan~?ldracetonebenz~l, %H,* ~:C(C5HlJ>CO C,H,* C(0H)-C=CH*C,H,' -This compound was prepared like the other benzylidene derivatives of a-compounds. It is deposited from its solution in boiling alcohol in colourless needles melting at 1 5 6 O . 0.1595 gave 0.4985 CO, and 0*1011 H,O. C,9H2s0, requires C = 85.29 ; H = 6.86 per cent. P-Amylanhydracetonebenzil does not interact with benzaldehyde. One of us is a t present engaged, conjointly with Mr. Arthur C. Michie, in studying the products of the oxidation of the various methyl homologues of anhydracetonebenzil. C=85*21 ; H=7*04. The foregoing two papers form a continuation of a general investi- gation of the reactions of ketonic compounds (compare Trans., 1897, 71, 123), and the expenses incident,al to the work have for some years past been in part defrayed by various allotments from the Government Grant Fund of the Royal Society. CHEMICAL DEPARTMENT, UNIVERSITY OF ABERDEEN.

ISSN:0368-1645    

DOI:10.1039/CT9017901024

出版商:RSC    

年代:1901

数据来源: RSC

摘要:

1042 BONE AND JERDAN: THE DIRECT UNION OF CIX.-The Direct Union of Carbon and Hydrogen. Part 11. By WILLIAM A. BONE and DAVID S. JERDAN. IN a previous paper on the subject (Trans., 71, 1897, 41) we showed that carbon. and hydrogen combine a t 1200' forming a saturated hydro- carbon; and further, that when the electric arc is passed between carbon terminals in an atmosphere of hydrogen, a saturated hydro- carbon is produced in addition to acetylene, the formation of each con- tinuing until a definite equilibrium bet ween the hydrocarbons, hydro- gen, and carbon vapour is established. It mas also shown that the same condition of equilibrium is attained when the arc is passed for some time in an atmosphere of either acetylene or methane under similar conditions. We had not, however, separated the saturated hydrocarbon, orCARBON AND HYDROGEN. PART 11.1043 hydrocarbons, formed a t 1200°, or in the arc, from the large excess of hydrogen always present in the gases obtained in the various experi- ments, consequently we were unable to produce any experimental evidence as to either the number or character of the saturated hydro- carbons formed in either case. I n absence of any such evidence, we provisionally assumed that the gases under examination contained no saturated hydrocarbon other than methane, and interpreted our analy- tical results accordingly. We felt a t the time that, so long as this question remained unsettled, the investigation of the subject could not be considered complete ; circumstances, however, €or a long time prevented our continuing the research, but during the past three years we have been continuously working on this and other points arising out of the earlier experiments. The present communication contains an account of a series of experi- ments which complete that part of our inquiry which refers to the character of the saturated hydrocarbons produced by the direct com- bination of their elements at l2OO0, and in the arc, and the successful solution of this problem has proved a very tedious and difficult matter.I n order to avoid undue repetition of experimental details, we must refer the reader to the account given in our previous paper of the methods employed for the puri6cation of the carbon and hydrogen required for the research, and also to the diagrams and explanations contained therein of the apparatus used both for the tube experiments a t 1200O and for the arc experiments.Practically the same arrange- ments, with certain minor improvements which further experience suggested, were adopted for the experiments recorded in this paper. The gas obtained by the interaction of carbon and hydrogen a t 1200°, or in the arc, contained, in addition to small amounts of hydro- carbon, a relatively very large volume of hydrogen, as well as a small percentage of nitrogen. The latter was unavoidably introduced with t,he original hydrogen employed, and to some extent also during the course of the experiment. Obviously, therefore, the only feasible method of identifying the saturated hydrocarbon, or hydrocarbons, in such a mixture, was to remove first of all any unsaturated hydro- carbon present (for example, acetylene in the case of the arc gases), and afterwards the free hydrogen by means of palladium. There would then remain a mixture of the saturated hydrocarbon, or hydro- carbons, and nitrogen ; an analysis of this mixture by explosion with excess of oxygen mould reveal whether it contained one hydrocarbon only, or a mixture of hydrocarbons.If the evidence so obtained pointed to the former alternative, as it was found to do in the case of the gas from the experiments at 1200°, the analytical results would alsoindicate the nature of the hydrocarbon. If, on the other hand,1044 BONE AND JERDAN: THE DIRECT UNION OF as in the case of the arc gases, the latter alternative were indicated, further investigation would be necessary.After submitting the gases under investigation to the series of operations indicated in the preceding paragraph, we were able to show that methane is the only hydrocarbon formed from its elements at 1200°, and that the saturated hydrocarbons produced in the arc con- sist of a mixture of methane with another (or possibly others) of its homologues. The methods employed for the identification of this other saturated hydrocarbon mill be fully explained later, a t present it will be suficient if we state that it ultimately proved to be ethane, A. Examination of the Gas obtained by the action of Hydrogen on Solid Carbon in tlie Tube Expriments at 1200'. Analyses published in the previous paper (pp. 49-51) had shown that the gases from the tube experiments contained no unsaturated hydrocarbon, It was therefore only necessary in this case to remove the diluting hydrogen in order to obtain the saturated hydrocarbon mixed with nitrogen only, This was accomplished by means of palladium black.Three different experiments were performed in which hydrogen, free from hydrocarbons, was passed over pure carbon heated to 1200' in the jacketed porcelain tube described in the previous paper (pp. 46-51) ; a current of pure hydrogen was maintained through the jaeket throughout each experiment. About 3 litres of the issuing gas were collected in each case in a glass holder over strong sulphuric acid. The holder, A , was attached to the palladium absorption apparatus as shown in Fig. 1 (p. 1045).The central portion of the apparatus consisted of a series of three glass bulbs, B, each of about 50 C.C. capacity, con- taining some 10 grams of freshly reduced palladium black, previously heated to redness in a vacuum. The tube leading from the bulbs was at one end twice bent at right angles, and sealed to a glass capillary tap, c6, on the other side of which was a T joint, 6, the latter serving to connect the bulbs through its vertical branch with the gas holder, A , and through its horizontal branch with the laboratory vessel, C', stand- ing over mercury in a wooden trough, D. The tube leading from the other end of the bulbs after being bent a t right angles was sealed to the glass capillary tap, c, through which a connection was made by means of a glass capillary tube with a manometer, E, standing over mercury in the same glass reservoir as the barometer, F, and also with the Sprengel pump, H, by means of which any gas in B could be diawn off and collected in tubes over mercury in the trough, K.The absorp- tion bulbs, B, were immersed in a rectangular tin trough, I;, containing water, so that they could be maintained at any temperature betweenCARBON AND HYDROGEN. PART 11. 1045 that of the room and looo, as circumstances required, There were only two rubber joints in the whole apparatus, namely, those connecting the holder, A, and the laboratory vessel, C, with the branches of the T piece leading to the tap, A, of the absorption apparatus. These two joints were made of stout pump tubing firmly wired at either end to the glass tubes which they served to connsct. A t the outset of an experiment, the taps, a and c, of the absorption bulbs and e, of the laboratory vessel, C, were opened and the whole apparatus, with the exception of the holder, A, was thoroughly ex FIG.1. The palladium absorption apparatus. hausted by means of the Sprengel pump, H. The tap e was then closed, the pump stopped, and by opening tap d of the gas holder, A, a quantity of the gas under examination was drawn over into B, until the level of the mercury in the manometer, E, had fallen within a few mm. of that in the vessel, G. The taps d and a were then closed, and the progress of the absorption of the hydrogen by the palladium in B could be followed by observing from time to time the mercury level in E.I n about 20 minutes, the absorption had ceased, and the residual gas was drawn off by the Sprengel pump into tubes standing over mercury in the trough, K. VOL. LXXIX. 4 B1046 BONE AND JERDAN: THE DIRECT UNION OF The water in the bath, L, was now heated to the boiling point, when much of the gas absorbed by the palladium during the previous opera- tion was liberated and drawn off through the pump, Finally, the bulba were exhausted at 100’ and cooled to the ordinary temperature t o he ready for the next absorption. These processes were repeated until the whole of the gas in A, usually about 3 litres, had been paased through the absorption bulbs and reduced to about 400-500 C.C. (first residue). This firat residue was then introduced in three or four p r - tions into the laboratory vessel, C, and subjected to a second concentra- tion in the same manner as before, when its volume was usually reduced to about 120-150 C.C.(second residue). This gas still contained hydrogen, and, indeed, i t is impossible to eliminate all the hydrogen from such a mixture of gases by a process of absorption with palladium, as the hydrogen in palladium hydride has an appreciable vapour pres- sure, even at the ordinary temperature. The last traces must be oxidised and removed as water by contact with ‘‘ oxidised ” palladium. After this second concentration, therefore, the absorption bulbs were detached from the apparatus, the palladium black taken out and heated to dull redness in a hard glass tube attached to a Sprengel pump until as much as possible of the occluded hydrogen had been removed.The pump was then detached, and the palladium maintained at a red heat in a gentle current of sir until i t had acquired the characteristic dark blue oxidation tint. The I ‘ oxidised ” palladium, after being cooled, was transferred again to the absorption bulbs, which were then sealed on to the apparatus, and the whole exhausted as before. The residual gas from the second concentration was intro- duced into C, and drawn over into the bulbs by momentarily opening taps e and a. The water in the bath, I;, was heated to the boiling point, and the gas allowed to remain in the bulbs at this temperature for 20 minutes or half an hour, after which the bulbs were allowed to cool, and the residual gas was drawn off through the pump into tubes standing over mercury and each containing a small piece of solid caustic potash.The residual gas so obtained from each of the three different experiments was analysed by exploding a measured volume of it with excess of oxygen, in some cases diluted with air free from carbon dioxide, and determining (1) the ‘ contraction ’ (C) on explosion ; (2) the ‘ absorption ’ (A) which occurred when the products of explosion were treated with potassium hydroxide, and (3) the oxygen (X) used up in the explosion.* * All gas analyses involved in this research were carried out by means of an im- proved form of McLeod apparatus designed by one of us, and described at a former meeting of the Society (Proc., 1898, 14, 154) ; we have found that this apparatus is especially adapted to the accurate analysis of hydrocarbon mixtures.The ‘ volumes ’ quoted in the text are deduced from the tensions of the moist gases in mm. ofCARBON AND HYDROGEN. PART 11. 1047 The results are tabulated as follows : Experiment. Volume of gas taken ..................... ,, oxygen added ............... ,, air added ..................... ,, treatment with KOH.. , , treatment with alkaline Contraction (C) ........................... Absorption (A) ........................... Oxygen (X) .............................. Volume aftor explosion ............... pyrogallol .............................. Ratio, CIA ........................... Ratio, C/X ........................... A. 65 '3 154.3 nil 152'0 119'3 67.3 32'7 - - 2.07 - (i) 40.3 66 '4 150.8 133-1 102.2 35.6 17 -7 35.5 - 2.01 1.0 B.(ii) 136'0 389.0 nil 406.8 346.0 178.0 118.2 60.8 121-0 1-94 0 *98 C. (i> 100.0 249'75 196.65 388.2 355.4 - 60.2 30.8 - 1-96 - - (ii) 121.5 175.2 232.1 431.5 383.6 97.3 47.9 97.05 2 *03 1 *o - - There can be no doubt that the hydrocarbon in these mixtures was in each case methane and methane only, for Methane requires C/A 2.0 and C/X 1.00. Propane ,, 1-00 ,) 0-60. Ethane ,, 1.25 ), o m . B. Examination of the Gae obtained in the Arc Expscl.imcnte. Our earlier experiments had shown that, in addition to acetylene, saturated hydrocarbons are formed by the direct union of carbon and hydrogen at the temperature of the electric arc. It wag necessary to ensure the complete removal of this acetylene and any other unsatur- ated hydrocarbons, as well as of the hydrogen, before attempting to identify the residual saturated hydrocarbon.As a fairly large volume of this residual gas was ultimately required, and as it was desirable to determine whether the character and compo- sition of the saturated hydrocarbon in any way depended upon the time during which the arc was maintained, the gas obtained in five different experiments was investigated. Each experiment was carried out in the arc apparatus as described in our previous paper (pp. 62-57), except that no samples of gas were collected during the time the arc was being passed, which varied from 10 minutes to an hour in the different experiments, As soon as the arc apparatus, 8, had cooled, the products were drawn off by means of the Sprengel pump, B (see Fig.2, p. 1048), and sent mercury when brought to a certain constant volume, at a constant temperature, in the meaauring vessel of the instrument, the vacuum ' in the barometer being always kept saturated with water vapour. 4 ~ 21048 BONE AND JERDAN: THE DIRECT UNION OF forward by means of a special device under a pressure of 2-3 mm. of mercury into the glass gas holder, C, previously filled with an ammoniacal solution of cuprous chloride. The solution so displaced was allowed to run away through the glass tap, D, into a large Winchester quart bottle. The device for drawing off the gas from A through the pump and sending it forward under pressure to C, consisted in immersing the delivery tube of the Sprengel in a large test-tube, E, three-quarters full of mercury, to which a side tube, F, had been fused.Over this delivery tube was fixed the funnel-shaped end of a vertical glass tube, G, the other end of which was attached to the tube leading into the holder, C. The mercury flowing over from the pump ran off through the side tube, P, into the bottle, El. The capacity of the gm holder, C, FIU, 2. was about halE as large again as that of the globe of the arc apparatus, so that after the products had been all collected in C, it still remained about one-third full of the ammoniacal cuprous chloride solution. The gas was allowed to remain in C for a t least two days, to ensure the complete absorption of acetylene and any trace of carbon monoxide, and was then transferred to another similar gas holder, previously filled with strong sulphuric acid, over vhich it was allowed to stand for other three or four days.The gas could now only consist of hydrogen, saturated hydrocarbons, and any nitrogen originally contained in the hydrogen. The gas holder was therefore attached to the palladium absorption apparatus for the removal of hydrogen, and treated as was the gas from the tube experiment (see p. 1044).CARBON AND HYDROGEN. PART 11. 1049 The residual mixture of hydrocarbons and nitrogen was anslysed by mixing a measured volume of it with excess of oxygen, diluted in some cases with air free from carbon dioxide and measuring (1) the contraction, C, on explosion ; (2) the absorption, A, which occurred when the products were treated with caustic potash.In certain cases, the oxygen used in the combustion of the hydrocarbons was also determined. (1) Blank Expriment.-In order to test the purity of the hydrogen used in these experiments and the validity of the method employed, a blank experiment was performed in which hydrogen prepared and purified as described in our previous paper (p. 45) was passed into the arc apparatus, and without the arc having been formed, was then transferred by means of the Sprengel pump, B (Fig. 2), to the holder containing the ammoniacal cuprous chloride solution. From thence it mas passed into a holder containing strong sulphuric acid, and after- wards subjected to the action of palladium in the absorption bulbs. The only differences between this blank and a real arc experiment were as follows.(I) A small quantity of nitrogen waa allowed to mix with the hydrogen be€ore it passed into the arc apparatus, in order that there might be a measurable residue for analysis after hydrogen had been removed in the final stages. (2) The arc was not formed, and (3) the final treatment of the gas with “oxidised” palladium at 100’ was omitted. As nearly as possible 2 litres of hydrogen were passed into the globe of the arc apparatus; after two “concentrations” in the palladium absorption apparatus it was reduced to about 80 C.C. This residue was exploded in the gas analysis apparatus with measured volumes of pure hydrogen prepared by the electroIysis of water, and subsequently purified by means of palladium, and of air free from carbon dioxide.The products of explosion were afterwards treated with caustic potash, when a very slight absorption occurred. The details of the analysis are as follows : Volume of residual gas taken ........................ 84.9 ,, hydrogen added ........................... 57.1 ,, air ,, ........................... 205.1 ,, after explosion .............................. 262.6 ,, after treatment with KOH ............... 262.3 Contraction, C = 86.7. Absorption, A = 0.3. Assuming that this small absorption was due to carbon dioxide formed by the combustion of methane originally present in the 2 litres of hydrogen used, it follows that this impurity did not exceed 0.015 per cent. by volume. We may therefore assume that the hydrogen used for the experiments recorded in this paper -was practically free from1050 BONE AND JERDAN: THE DIRECT UNION OF Time during which arc was main- tained .................................... Volume of residual gas after removal of acetylene and hydrogen .........Volunie of residual gas after de- ducting nitrogen ....................... hydrocarbon impurity. Further, since the observed contraction is very little more than the sum of the contraction required by the hydrogen added (85.7) and the methane (0.6) present, this blank experiment indicates that practically the whole of the original hydrogen used had been removed by the palladium black. It was, however, deemed advisable not to omit the final treatment with 6' oxidised " palladium in the actual experiments. (2) Actual Expcriments.-The arc apparatus was in each case about two-thirds filled with hydrogen (about 2 litres), and the arc (voltage = 160) maintained for a period varying from 10 minutes to an hour in the different experiments, After removal of acetylene and hydrogen in the manner already described, the residual gas was analysed by explosion with excesq of oxygen in the usual manner.The details of each experiment, and the analytical results are given in the following table : 10 mins. 30 mins 40 C.C. - 35 c. c. - Experiment. 1 I. 1 11. 1 hour I hour 1-1- 50 C.C. Volume of gas taken. .................... ,, oxygen added ............... Volume after explosion ................. ,, treatment with KOH.. Contraction (C) ........................... Absorption (A) ........................... 46 C.C. 60'9 510.9 456-2 382.9 115-6 73'3 62.7 528'4 476'6 405.2 114'5 71'4 36 '1 330'0 315.1 284-2 61.0 30'9 74-2 482'2 462.2 4029 94'2 59.5 Ratio, C/A ............................. ....I 1-58 1 1-65 111.30 mina, 60 C.C. 54 C.C. 55.7 4433 388.0 318-0 111'0 70'0 1.58 i- 1-62 I 1'58 I * The large amount of nitrogen in this reeidual gas was due to an accidental in- leakage of air during the final absorptiou of hydrogen by means of oxidised palladium, These experiments prove beyond all possible doubt that hydrocarbons of the methane series are produced when the electric arc is made between carbon terminals in an atmosphere of hydrogen, The actual quantity of these saturated hydrocarbons so formed is to some extent dependent upon the time during which the arc is maintained, attaining a maximum, as our earlier experiments showed, after about half an hour, and after- wards remaining fairly constant (see also previous paper, pp.57-68}. Further, it is a remarkable fact that the ratio C/A found on exploding the residual saturated hydrocarbons with excess of oxygen is practically constant (1.6) and independent of the time during which the arc isCARBON AND HYDROGEN. PART XI. 1051 maintained. It may therefore be concluded that whatever may be the number and composition of the saturated hydrocarbons obtained in a given experiment they are formed simultaneously, and at equal rates throughout, The experiments indicate, moreover, that methane is one of the saturated hydrocarbons as the ratio C/A= 1.6 could only be given by a mixture of saturated hydrocarbons containing methane (p.1047). The analytical numbers, however, afford no clue as to either the character or the number of the other saturated hydrocarbons. For example, the results obtained in the case of the residual gas from ex- periment I would be given by any one of the following mixtures : CH, ...... 62.5 CH, ... 69.5 CH, ... 75.1 per cent. C,H, ... 34.0 C,H8 ... 16.9 C,H,, ... 11.3 ,, *N, ...... 13.5 N, ...... 13.6 N, ...... 13.6 ,, (1). (2). (3). - - 100*0 100*0 100.0 or, indeed, by an unlimited number of other mixtures of nitrogen methane, and one or more other saturated hydrocarbons. Further, since the densities of all such possible mixtures are identical, it was not possible to distinguish between the various interpretations of the chemical analysis by means of a density determination, With the view, however, simply of checking the chemical analysis, the density of the residual gas obtained in experiment 11, referred to hydrogen, was determined ;, it was found to be 11 *7 inatead of 11 *4 as calculated from the analysis.0. Difukon Expavirncnts with the Residual Gas fiom the Arc Exprimcnts. It waa now necessary to obtain some evidence as to the character of the saturated hydrocarbons other than methane formed in the arc ex- periments. It seemed probable that one or other, if not both, of two methods would enable us to settle the question. The first method consisted in subjecting some of the residual gas from the arc experi- ments to a slow process of diffusion through porous clay tubes many times repeated, and comparing its behaviour with that of artificial mixtures of methane and nitrogen with otrher saturated hydrocarbons (ethane, propane, $c.) giving the same analytical results. The other method, which the kindness of Professor Ramsay enabled us to carry out, consisted in liquefying the hydrocarbons in the residual gas from * Results for nitrogen given in this paper are all calculated ' by difference.1052 BONE AND JERDAN: THE DIRECT UNION OF the arc experiments, and subsequently fractionally distilling the liquid.For the purpose of the diffusion experiments, we mixed together 30 C.C. of residual gas from experiment I. 45 $ 9 ,, 111. 45 9 , 9 9 IV. -- Total 120 C.C. The percentage composition of this mixture, according to analysis, is shown below, supposing that there are only two saturated hydrocarbons present, and that the second is (1) ethane, (2) propane, and (3) butane.CH, ...... 54.3 CH, ... 70.7 CH, ... 76.2 per cent. C,H, ... 32% C,H8 ... 16.4 C,HIo ... 10.9 .. N, ...... 32.9 N, ...... 12.9 N, ...... 12.9 .. (1). (2). (3). The relative ratio at which the constituents of such mixtures would diffuse through a porous plug can, OF course, be calculated from their densities and partial pressures; taking the rate for the methane in each case as unit, the rates for the other constituents are as follows : (1 )* (2). (3). Ethane - - ............ 0.441 - 0.139 - Butane ............ - - 0.074 Nitrogen ............ 0.18 0.133 0-128 Propane ............ Di$usion Apparatus (see Fig. 3, p. 1053).-This consisted of four glass gas wash-bottles, A , B, C, D, arranged in series, as shown in the dia- gram.The central wide glass tube, which fitted into the neck of each bottle by a ground glass joint, was drawn out in the blow-pipe flame and then cut off about an inch below the joint. To it was attached a piece of clay pipe stem about 3-4 inches long, closed at the bottom in the oxyhydrogen flame. The four bottles were connected by fused glass joints, and between each pair was inserted a glass T joint ter- minating in a glass stopcock (b, c, d). The bottle, A, was connected by means of fused glass joints through a similar T piece with the laboratory vessel, E, standing in a wooden trough over mercury. The fourth bottle, D, was connected also by means of fused glass joints with a T piece leading through its vertical branch to the manometer, M, and through its horizontal branch to the Sprengel pump, G.H is a barometer standing in the same mercury reservoir, K, and attached t o the same millimetre scale as the manometer, M. The vertical branches of the T pieces between the bottles, and be-CARBON AND HYDROGEN. PART 11. 1053 tween A and E, were continued downwards beyond the stopcocks, a, 6, c, d, through joints made of stout india-rubber pump tubing" to a horizontal glass tube, PP, which led to a second Sprengel pump (not shown in the diagram), with its barometer and manometer. This second Sprengel pump served to exhaust the apparatus at the outset of a diffusion experiment,, and at the finish to collect the last fraction. All other fractions mere drawn off through the first Sprengel, G, and collected in tubes, L, standing in the trough, N.At the outset of an experiment, the whole apparatus was exhausted by opening all the stop-cocks, a, 6, c, d, e, and leading to the two pumps. As soon as the laboratory vessel, B, was full of mercury, the stopcock, e, was shut. Finally, when the exhaustion was complete, The difwion apparatus. stopcocks, a, b, c, and d, leading to the second pump, were closed. The apparatus was now allowed to stand for 24 hours, to see whether the ground glass joints at the top of the four diffusion bottles, A, B, C, and D, were quite air-tight. It was found possible to make them so by pouring melted paraffin wax over the outer surface of each joint when the apparatus was exhausted.The gas to be diffused was introduced into the laboratory vessel, 3, and then by opening the stopcock, e, it was drawn over into the first diffusion bottle, A. The diffusion process a t once began, and the various it With the exception of these four joints, which were shut off from the bottles throughout the diffusion operations, and the four ground glass joints of the bottles, all other joints in the apparatus were of fused glass.1054 BONE AND JERDAN: THE DIRECT UKION OF fractions, excepting only the final fraction, were collected through the first Sprengel pump, G. Finally, the stopcocks a, 6, c, d were opened, and the residual gas, that is, the last fraction, was drawn off through the second Sprengel pump. It will therefore be clear that in each diffusion operation the gas passed through four porous plugs.The amount of gas taken for each ‘‘ fractionation ” varied within very wide limits, Usually, it amounted to between 25 and 120 c.c., and the time required for each operation varied from 9-18 hours, being shorter the larger the amount of gas involved, Difwion of a Mixture of equal Volumes of Methane and Oxygen in th Apparatus.-To obtain some idea of tho efficiency of the apparatus, 100 C.C. of a mixture of equal volumes of methane and oxygen (oxygen has nearly the same density as ethane, which is, next to methane, the lightest saturated hydrocarbon) were slowly fractionated. Four nearly equal fraction8 were collected, and the oxygen in each deter- mined. Oxygen in original gas ..................60.0 per cent. ,, fraction I ..................... 42.5 ,, ), fraction 11.. .................. 52.0 ,, ,, fraction I11 .................. 5 8 5 ,, ,, fraction I V .................. 69.0 ,, Twenty C.C. of fraction I mere rediffused, and the first 6 C.C. col- lected and analysed. Scheme of Dzfusion Experiments with Arc Gases.-One hundred and twenty C.C. of the arc gases were introduced into the diffusion apparatus as already described, allowed to diffuse, and collected in four fractions, as follows : It contained 30 per cent. of oxygen. Fraction A = 30 C.C. Fraction C = 40 C.C. ,, B = 30 ?, D = 20 Prccction C was then rediffused, tho first 5 C.C. collected were added to A, the next 13 C.C. to B, and the residual gas collected separately. (Fraction C’.) The first 15 c.c, were added to A, the next 14 C.C.to C’, and the residue to D. Fraction B was then rediffused. At this stage, therefore, we had Fraction A = 50 C.C. Fraction C’ = 36 C.C. Fraction D = 34 C.C. Praction A was diffused, and collected in two fractions. Fraction A’ = 25 C.C. Fraction A“ = 25 C.C. Fraction A’ was finally diffused and collected in three approxi- mately equal fractions, a, 6, and c.CARBON AND HYDROGEN. PART If. 1055 Fraction a. (1 1 (2) CH, = 72'0 CH, = 80.6 C,H, = 16.8 C,H, = 8.4 N, = 11.2 N, = 11.0 Fruction D was diffused, and collected in two fractions. Fraction D' = 10 C.C. Fraction D" = 24 C.C. Fraction x. OH, = 36.6 CH, = 59.3 C,H, = 45.3 C,H8 = 22.6 N, = 18.1 N, = 18.1 (1) (2) Methane - Methane - - - 4.29. - - 9.6. Ethane Propane Methane - Methane = 2.624. - - 0.1108.Ethane Propane The ratios of the two hydrocarbons are important in view of the re- sult of the two following experiments, in which artificial mixtures were diffused. Dafwion of a Mixtuoa of Hethane, &?ham, and Nitrogm-A mix- ture of methane, ethane, and nitrogen was prepared as nearly as possible of the same composition as that of the residual gas from the arc experiments, assuming that the second hydrocarbon was ethane. The methane" employed was prepared by the action of a mercury- aluminium couple on a mixture of methyl iodide and methyl alcohol, and in order to remove any traces of hydrogen it might contain, the gas was passed over oxidised palladium sponge heated a t looo. The ethane" used was prepared by decomposing zinc ethyl with * The purity of both the methane and ethane (as well as of the propane used in the next experiment) was in each case proved by a careful analysis (explosion method), the details of which it is not necessary to record.The ratio C/A for the methane was found to be 2.0, and for the ethane 1-254.1056 BONE AND JERDAN: THE DIRECT UNION OF water, and the nitrogen by passing a slow current of air over red-hot copper turnings until the whole of the oxygen had been removed. The gases were then mixed in a small graduat.ed holder over mer- cury. On analysis, the mixture was found t o have the following per- centage composition : Methane = 51-77 ; ethane = 33-15 ; nitrogen (by difference) = 15.18, with ratio C/A = 19575. One hundred and twenty C.C. of this mixture were subjected to a precisely similar series of fractional diffusions as have been described in the case of the residual gas from the arc experiments, and finally the fractions a and x so obtained were analysed, with the following results : Fraction a.Fraction z. Volume of gas taken .......................... 49.2 45.0 ,, oxygen added ..................... 483.95 440.0 Volume after explosion ........................ 445.4 40'7.2 ?) treatment with KOK ......... 395.9 354-3 Contraction (C) ................................. 87-75 77.8 Absorption (A) ................................ 49.5 52.9 Ratio C/A ....................................... 1-77 1-47 The behaviour of the mixture of methane, ethane, and nitrogen when subjected to the process of fractional diffusion was similar to that of the residual gas from the arc experiment.The percentage composition of the two fractions a and z were therefore : a. 2. Methane .............................. 70.1 34.7 Ethane ................................. 15.2 415 Nitrogen (by difference) ............ 14.7 25.8 Ratio ____ Ethane ..................... 4.62 0.835 Bi$.usim of a Mixture of Hethane, Propcine, and Nitrogen.-The propane used in this experiment was prepared by the action of sodium amalgam on a solution of isopropyl iodide in ethyl alcohol; analysis showed it to be pure (ratio C/A= 0.997). The three gases were mixed in a graduated holder over mercury; on analysis, the mixture was found to have the following percentage composition : Methane = 65.5 ; propane= 17.65 ; nitrogen (by difference) = 16.85, with ratio C/A = 1.55, which is nearly that of the residual arc gases, assuming for the moment that the second hydrocarbon was propane.The mixture was subjected to a process of diffusion precisely similar to that carried out with the residual arc gases, and with the mixture of methane, ethane, and nitrogen. This mixture seemed to behave differently during the diffusion MethaneCARBON ARD HYDROGEN. PART IJ. 1057 Fraction. a 19-75 2.10 operations from either the arc gases or the mixture of methane, ethane, and nitrogen. The ' heavier ' fractions passed through the apparatus much more slowly, and the final fractions were only pumped out with great difficulty; last traces of propane obstinately clung to the plugs, and were probably never removed.The fractions ct and x were finalIy analysed, with the following results : (1.) If ethane (2) If propane is present. is present. Fraction. Fraction. z a z n z 4.29 0.808 1 9-6 2'624 Fraction a. 42.1 Volume of gas taken ........................... ,, oxygen added ..................... 388.9 Volume after explosion ........................ 357-85 9 9 treatment with KOH ......... 318*70 Contraction (C) ................................. 73.15 Absorption (A) ................................. 39-15 Ratio C/A ...................................... 1-86 Fraction z. 55.3 494.3 466.7 408.0 8 2-9 58.7 1 *41 The percentage composition of these fractions would therefore be : Methane ........................... 80.80 43.8 Propane .............................. 4-09 20.8 Nitrogen ...........................15.11 35.4 a. x. are 19.75 and 2-10 respectively. methane and the ratios ~ propane The results of these diffusion experiments are most easily under- stood if the ratio for the lightest and heaviest fractions obtained by the diffusion of the two mixtures of known composition be compared with the same ratio for the corresponding fractions obtained when the arc gases are subjected to tlie same process. other hydrocarbon Fraction. a z Methane Other hydrocarbon = 4'62 0'836 - 4 '62 --= 5-53 R, R, 0.836 - Arc gases. Mixture, -- 19-75 - 9.4 -I 4-29 - 5.3 9*6 - 3.6 2'10 1 0.808 12.624- The similarity between the results obtained with the artificial1058 BONE ANT) JERDAN: THE DIRECT UNION OF mixture containing ethane and the residual gas from the arc experiment is so great that very little doubt can remain as to the presence of ethane in the arc gases.The similarity is especially brought out by comparison of the ratio R,/RZ. I n the two cases quoted, the ratios are almost identical, namely, 5-53 and 5.3, whereas if we assume the second hydrocarbon in the arc gases to be propane, we find Ra/R, = 3.6, whilst for the artificial mixture containing propane the value 9.4 is obtained. The evidence afforded by the diffusion experiments is therefore much more in favour of the supposition that the second hydrocarbon in the arc gases was ethane than that i t was propane. On the other hand, it does not exclude t h e possibility of the gases having con- tained some small amount of propane in addition to methane and ethane.The idea of separating the hydrocarbons contained in the arc gases by a process of liquefaction and subsequent fractional distillation occurred to us a t :an early stage of our work, indeed before the dif- fusion experiments were seriously contemplated. We, however, had no means of carrying out the idea until Professor Ramsay, hearing of our difficulty, kindly offered to help us, and we desire to express our best thanks to him for his goodness in enabling us to bring our investi- gation to a satiBfactory conclusion. The following table of boiling points, expressed in degrees absolute, shows that there is a greater difference between the boiling points of methane and ethane than between those of benzene and the xylenes, and as a difference of so many degrees at so low a temperature means relatively much more than a similar difference at higher temperatures, the prospect of almost completely separating methane and ethane seemed good : Boiling points.Boiling points. Diff. Diff. ....... Benzene., .......... 353.4O>29 *cJ Nitrogen.. 90>3 40 Propane ......... 228 >48 - Toluene 383.3 >31,7 Methane ......... 113 ............ Ethane ......... 180 >67 Xylenes ... 411 to 415 Butane ......... 274 61 *6 About 100 C.C. of various fractions of the arc gases left over from the diffusion experiments were thoroughly mixed in a small holder over mercury; a portion of the mixture was analysed with the follow- ing results :CARBON AND HYDROGEN. PART 11. 1059 Volume of gas taken ........................... 38.5 ,, oxygen added ........................344.3 Volume after explosion ........................ 312.25 ,, treatment with KOH ......... 268.25 Contraction (C) = 70.55. Absorption (A) = 44.00. Ratio C/A = 1.60. The gas would therefore have the following percentage composition, assuming (1) that the second hydrocarbon is ethane, (2) that i t is propane : (1) (2) Methane ............ 54.0 Methane ............ 69.0 Ethane ............ 30.0 Propane ............ 15.0 Nitrogen ............ 16.0 Nitrogen ............ 16.0 It will further be noticed that this was practically the composition of the original arc gases before diffusion. About 70 C.C. of this mixture were sealed up in an exhausted bulb, and forwarded to Professor Ramsay, who carried out the fractionation for u s in the laboratory of the University College, London, as follows.The gas was passed into a small gas bulb immersed in boiling liquid air ; a large portion of i t solidified as white, snow-like crystals on the inner surface of the bulb, whilst another portion either liquefied or formed a vitreous, glassy solid. A third constituent, namely the nitrogen, which was only liquefied under pressure, was allowed to pass off uncondensed. The contents of the bulb were slowly volatilised and collected over mercury in three as nearly as possible equal frac- tions, A, B, and C, of about 20 C.C. each. The crystalline solid (the methane) disappeared during the early stages of the process, and the liquid or vitreous solid was entirely converted into gas at a very low temperature, certainly much below the boiling point of butane, and probably that of propane also, After the third fraction had been collected, there remained no residuum of gas in the apparatus.From the behaviour of the gas during the process, Professor Ramsay con- cluded that it certainiy contained no butane, and that the second hydrocarbon was more probably ethane than propane. F-action A was found, on analysis, to consist of methane with some 15 per cent, of nitrogen, as the following figures indicate : Volume of gas taken ........................... 49.80 ,, oxygen added ........................ 124.90 ,, air added (oxygen = 76.37) ...... 364.35 Volume after explosion ........................ 455.0 9 ) treatment with KOH 412.9 ......... 9 , treatment with alkaline pyro-1 296,1 gallol........................... Oxygen used (124.9 + 76-37 - 116.8) ......... 84.471060 BONE AND JERDAN: THE DIRECT UNION OF Contraction (C) = 84.05. Absorption (A) = 42.10. Ratio CIA = 2. The gas therefore had the percentage composition Methane = 84.5. Nitrogen = 15-5. Fraction B on analysis gave the following numbers : Volume of gas taken ............................. 38.0 ,, oxygen added ........................ 99.8 ,, air added (oxygen = 77.7) ......... 370.5 Volume after explosion ........................... 432.5 treatment with KOH ............ 390.9 99 9 9 treatment with alkaline pyro-] 295.5 gallol ........................... Oxygen used (99.8 x 0*988+77.7-95a4)...... 80.9 Contraction (C) = 75% Absorption (A) = 41.6.Ratio CIA = 1.82. The gas evidently therefore contained a large quantity of methane with some ethane or propane and also nitrogen. Its percentage corn- position would be as follows, assuming (1) that the second hydrocarbon was ethane, (2) that it was propane : (1) (2) Methane ......... 83.53 Methane ......... 90-0 Ethane ........... 12-97 Propane .......... 6.5 Nitrogen.. ....... 3.50 Nitrogen ......... 3.5 The amount of oxygen actually used in the explosion agrees very closely with the 80.73 vols. required by 38 vols of either of the fore- going mixtures, if we allow for the fact that the oxygen added was found on analysis to contain 1.2 per cent. of nitrogen. Fruction C, on analysis, yielded numbers agreeing very closely with those required on the supposition that it consisted of nearly pure ethane : Volume of gas taken .............................32.7 ?, oxygen added ........................ 483.0 Volume after explosion ......................... 435.0 ,? treatment with KOH .......... 372.0 Contraction (C) = 80 7. Absorption (A) = 63-0. Ratio C/A = 1.28. It is evident therefore that this fraction either consisted of ethane with a small quantity of methane, or that it contained nearly equal volumes of methane and Now pure ethane requires C/A = 1-25.CARBON AND HYDROGEN. PART 11. 1061 propane. figures indicate : Methane = 2.6 ('7.92 per cent.) Methane = 17.7 (54.0 per cent.) Ethane =30*2(92.07 ,, ) Propane =15*1 (46.0 ,, ) There was evidently no nitrogen present, as the following -- -- 32.8 32.8 The percentage composition of the tiwee fractions mould be as follows, (1 ) on the supposition that the second hydrocarbon was ethane, (2) that it was propane : A.B. C. (1) Methane ............ 84.5 83.53 7.92 Ethane ............... nil 12.97 92.07 Nitrogen ............ 15.5 3.50 nil (2) Methane ............ 84.5 90.0 54.0 Propane ............... nil 6.5 46.0 Nitrogen ............ 15.5 3.5 nil The composition of the middle fraction, B, almost excludes the supposition that the second hydrocarbon was propane, for if it were so, the second series of figures would indicate that whereas we had completely separated nitrogen and methane whose boiling points differ by only 34O, we had not effected a separation of two hydrocarbons whose boiling points differ by as much as 115'. To further test the matter, however, 10 C.C.of the fraction C were subjected to a process of diffusion in the apparatus we have described, which in one operation effected a considerable separation in a mixture of equal volumes of methane and oxygen (see page 1054). I f fraction C consisted of nearly equal volumes of methane and propane, we should expect to get a very considerable separation on difhsion; on the other hand, if the gas was nearly pure ethane, on analysis very little difference should be found between the ratio C/A for the heaviest portion and 1.28, the ratio for the original gas diffused. The 10 C.C. of gas were accordingly very slowly diffused through the apparatus, the operation extending altogether over 12 hours, The first 6.5 C.C. collected were rejected, and the last 3.5 C.C.wereanalysed, with the following results : Volume of gas taken. .......................... 27-95 ,, oxygen added ..................... 488.35 Volume after explosion.. ...................... 450.9 ,, treatment with KOH ...... 398.5 Absorption (A) = 52.4. Contraction (0) = 65.4. Ratio CIA= 1.25. VOL. LXXIX. 4 c1062 THE DIRECT UNION OF CARBON AND HYDROGEN. PART IT. The result is, we are inclined to think, quite decisive. The evidence is overwhelmingly in favour of the view that the second saturated hydrocarbon formed when the electric aro is maintained between carbon terminals in an atmosphere of hydrogen is ethane, Discussim of Results. Our experiments prove that methane, the simplest of all hydrocar- bons, is the first to be formed by the direct combination of its elements, for it alone is produced at the lower temperature of 1200O when the velocity of combination is just measurable. At Some temperature, a t present unknown, between 1200O and 3600O the temperature of the arc, acetylene, and ethane begin to be formed; in the arc the formation of all these hydrocarbons continues until a certain equi- librium between them and carbon vapour and hydrogen is established.Calculating from the results of our earlier experiments, interpreted in the light of our later work, we find that the proportions between the three hydrocarbons and hydrogen when this equilibrium is attained are somewhat as follows : Hydrogen ........................... 90-91 per cent. Acetylene ........................... 7- 8 ,, Methane............................. 1-25 ,, Ethane .............................. 0.75 ,, It is, of course, open to discussion whether acetylene and ethane are formed in the arc directly from their elements, or indirectly by the decomposition of methane. At first sight it may seem probable that methane is the first product of the combination of carbon vapour with hydrogen in the arc, a13 it undoubtedly is of the action of hydrogen upon solid carbon a t 1200O. The fact, however, that methane and ethane are produced simultaneously, and a t rates which bear a con- stant ratio to each other during the whole time the arc is maintained, indicates, we think, that ethane is formed directly from its elements, and not indirectly by the decomposition of either methane or acetylene. With regard to the acetylene, a study of the results recorded in our previous paper, particularly those of the arc experiments I1 and 111, shows that its rate of formation bears a nearly constant ratio to the rates of formation of the other two hydrocarbons, and, further, that the quantity of it present at any given moment throughout an experi- ment is always far in excess of the proportions of the other two hydro- carbons, even when these are considerably below the 'equilibrium limite.' These considerations, we think, point to the conclusion that acetylene also is formed directly from its elements. It is, however, difficult to draw any hard and fast conclusiom as to the character and sequence of the chemical changes which occur in the arc experiments,COLLIE : DECOMPOSITION OF CARBON DIOXIDE. 1063 Our results aIso open up the question of the stability of hydro- carbons at high temperatures. The recent publication of preliminary notices of work on the decomposition of varioue organic compounds, including aome hydrocarbons, by W. Ipatieff (Bur., 1901, 34, 596) and also by W. Lob (Ber., 1901, 34, 915) make it desirable that we should now indicate the lines upon which we have been working on this subject for some months, in order that unnecessary overlapping may be prevented. If, as we have shown, methane is the only hydro- carbon to be formed a t 1200' from its element, it is probable that it alone can permanently exist at this temperature ; we are, therefore, investigating the decomposition of methane, ethane, ethylene, acetylene, and certain aromatic hydrocarbons at 1200' or t.hereabouts, and hope shortly to communicate some results to the Society. We have much pleasure in expressing our indebtedness to Professor Dixon for valuable criticisms at various times during the course of the research, to Professor Ramsay for so kindly helping us in the separa- tion of the saturated hydrocarbons obtained in the arc experiments, to Messrs. Johnson and Matthey for the loan of palladium required for the hydrogen absorptions, and finally to the Government Grant Committee of the Royal Society for repeated grants which have enabled ug to purchase the special apparatus required for the research, including that used for the gas analyses involved. THE OWENS COLLEGE, MANCHEGTER.

ISSN:0368-1645    

DOI:10.1039/CT9017901042

出版商:RSC    

年代:1901

数据来源: RSC

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COLLIE : DECOMPOSITION OF CARBON DIOXIDE. 1063 CX.-On the Decomposition of Carbon Dzoxide when submitted to Electric Discharge at Low Pressures. By J. NORMAN COLLIE, Ph.D., F.R.S. 'DURING some experiments which were being made on the relative resist- ance of gases at low pressures in vacuum tubes to the passage of the electric spark, carbon dioxide was found to exhibit peculiarities. As these pointed t o decomposition of the gas, the literature bearing on the subject was consulted, and as the evidence was conflicting, an inquiry into what occurred seemed necessary. So far back as 1860, H. Buff and A. W. Hofmann (this Journal, 12, 282) noticed that at the ordinary pressure carbon dioxide under- went imperfect decomposition when subjected to the sparks from an induction coil.They say, '' the spark traverses the gas with a violet light, In the commencement of the experiment, the expansion is very 4 c 21064 COLLIE : THE DECOMPOSITION OF CARBON DIOXIDE WHEN appreciable; 7; C.C. of carbonic acid, after a few minutes, became 8$ C.C. ; but further decomposition proceeded with extreme slowness, until, after the lapse of half an hour, the accumulated carbonic oxide exploded with the liberated oxygen, when the original volume of the carbonic acid was restored, again to undergo asimilar set of changes.” But in opposition to this, in a very comprehensive paper on the spectra of carbon compounds, Prof. A. Smithells (Phil. Mag., 1901, [vi], 1, 476) brings forward arguments for the stability of carbon dioxide when submitted to the electric discharge at the low pressure of a vacuum tube, although a t the same time he points out that this idea is in opposition to the views which he takes with regard to the Swan spectrum being that of carbon monoxide.As it did not seem difficult to obtain the gases from the interior of a vacuum tube in sufficient quantity for analysip, the following investi- gatiori was made. The form of apparatus used was as follows : The carbon dioxide could be introduced by means of the tap C, the gas entering into the space between the taps A and D. The pressure was read off on the gauge. The distance between the two electrodes, which were of stout aluminium, was 25 inches ; the capillary tube join- ing the two ends of the vacuum tube was of 1 mm. bore. Pure carbon dioxide, made by heating sodium hydrogen carbonate, was introduced into the tube in the ordinary manner and dried by passing over a layer of phosphoric oxide.Connected with the vacuum tube was a mercury gauge to measure the pressure of the gas. On the vacuum tube were two glass stopcocks, one at each end, so that during the sparking of the gas only that portion confined in the tube should be submitted to the discharge. Any gas, therefore, introduced into the vacuum tube after sparking could be directly pumped out by means of a T6pler pump and analysed.SUBMITTED TO ELECTRIC DISCHAROE AT LOW PRESSURES. 1065 A Newton-App coil and a couple of accumulators were used for the production of the electric discharge. I n the first set of preliminary experiments some of the pure carbon dioxide was sparked during a period of from 1 to 10 minutes under a pressure of 5 mm.It was found that the residual gas, when pumped out, was largely insoluble in caustic soda, and that the carbon dioxide, in amounts varying from 60-70 per cent., had been decomposed. This residual gas, when submitted to an electric spark under the ordinary pressure, exploded, and then was soluble (all except a small bubble) in caustic soda. Large quantities were therefore experimented with in order to obtain 8 greater volume of the residual gas. This was effected by mixing the products from several experiments. As a result, it was found that, after being filled four times a t 3 mm. pressure, and the contents sparked for 3 minutes, the tube yielded 2.2 C.C. of gas. 1.7 C.C.were left after treatment with caustic soda ; 0.5 c.c., therefore, of undecom- posed carbon dioxide had been absorbed. On exploding the 1.7 c.c., it became almost entirely soluble in caustic soda. By calculation, the original volume of the carbon dioxide must have been 1.633 c.c., and of this 1.133 C.C. had been decomposed, which is equivalent to 69 per cent. Several other experiments were made, and always with the same result, the amount of decomposition varying from 65-70 per cent. I n two of the above experiments, during the decomposition of the gas, the vacuum tube was in open connection with the mercury gauge, and the increase in pressure could be noticed even after the tube had been allowed to cool. To test whether the aluminium electrodes were in any way instru- mental in effecting the decomposition of the carbon dioxide, stout platinum ones were substituted for them, and at first very contradic- tory numbers were obtained.The gas was introduced at pressures varying from 24 to 6 mm., and the sparking continued for 5 minutes in each case. The amount of carbon dioxide decomposed varied from 33 to 57 per cent. During the passage of the current, however, it was noticed that flickerings occurred in the tube when the negative electrode became hot, and that the glow on the hot negative electrode changed from the livid blue exhibited by the mixture of decomposed gases to the purple colour which was characteristic when the gas was first subjected to the electric discharge, this seeming to indicate that recombination was taking place.Accordingly, the tube was again filled at 5 mm, pressure and sparked for 1 minute. On pumping out the gas, it was found that 65 per cent. had been decomposed into carbon monoxide and oxygen. The tube was again filled a t the same pressure, and subjected for1066 COLLIE: THE DECOMPOSITION OF CARBON DIOXIDE WHEN 5 minutes to the same spark. A more powerful current was turned on till the platinum negative electrode became red hot ; the flickerings were again noticed, and the colour of the incandescent gas at the hot platinum electrode changed as before to a purple colour. The current was stopped, and the gases analysed. Only 22 per cent, had been decomposed. An electrodeless tube was next tried, and when it was filled at 5-6 mm. pressure and a strong current employed for 1 minute, it was found that no less than 50 per cent.of the carbon dioxide under- went decomposition into carbon monoxide and oxygen. I n another experiment, which wa8 carried on for 5 minutes, 62 per cent. of the gas was decomposed. These rssults show that carbon dioxide gas is undoubtedly decomposed to a large extent by the current, irrespective of the electrode employed, Many more experiments were made with another tube in which one electrode was stout aluminium and the other a coiled piece of thin platinum wire. In every case, when the stout aluminium wire was the negative electrode and the tube was filled a t pressures varying from 1-12 mm., 70 per cent. of the carbon dioxide was found to be decomposed after 1 to 2 minutes’ sparking.The following experiment, however, is worth recording i n detail. The residual gas from several experiments, after all the carbon dioxide had been removed, was analysed. Part of it was found, on explosion, to yield nothing but carbon dioxide. Also, another part was reduced exactly one-third in volume by treatment with an alkaline solution of pyrogallol, and the remaining two-thirds was absorbed entirely by an ammoniacal solution of cuprous chloride. It wag therefore a mixture of two volumes of carbon monoxide and one volume of oxygen. Some of this gas was introduced in portions a t 10 mm. pressure into the vacuum tube and sparked for 2 minutes, the aluminium being the negative electrode. After pumping out finally, 9.3 C.C. of residual gas were obtained, This volume was reduced to 7-6 C.C.when trested with caustic soda, showing that carbon dioxide had been formed, and that the mixture of carbon dioxide, carbon mon- oxide, and oxygen was in the same amount as if 74 per cent. of carbon dioxide had been decomposed. The residual 7.6 C.C. of carbon monoxide and oxygen were next intro- duced into the tube in the same manner, but a t a lower pressure, namely, 2 mm., in order that when the platinum electrode was made the pega,tive pole it might be heated by the current. After pumping out, the 7.6 C.C. had decreased to 5.2 C.C. On treatment with caustic soda, only 0.6 C.C. remained, which proved to be pure carbon monoxide. Thus, by merely varying the conditions of the experiment, carbonSUBMITTED TO ELECTRIC DISCHARGE AT LOW PRESSURES.1067 dioxide had been first decomposed, to the extent of 70 per cent., into carbon monoxide and oxygen. Next, the carbon monoxide and oxygen alone, by the same treatment, partly recombined, forming carbon dioxide, but when a hot platinum electrode and increased current were employed, the carbon monoxide and oxygen combined almost coxn- pletely to form carbon dioxide, in fact they would have probably done so entirely if, in the splashing of the platinum on to the side of the tube, a small amount of oxygen, 0.3 c.c., had not been occluded by the metal. Carbon dioxide which had been dried in the pump for about 50 hours decomposed just as w i l y as undried gas passed straight into the tube, for some gas thus freed from aqueous vapour when sparked under 5 mm.pressure for one minute was found, on analysis, to have been decom- posed to the extent of 65 per cent. The following results show that the decomposition was fairly rapid. Carbon dioxide sparked under 10 mm., 3 mm., and 1 mm. pressure for only 10 seconds decomposed to the extent of 32, 55, and 63 per cent. respectively. Carbon monoxide, however, seems to be far more stable. When sub- jected to the same treatment with an ordinarily powerful spark, the current may be left on for half an hour with no appreciable result ; moreover, the gas gives no turbidity with baryta water. If, however, the current is sufficiently strong to make the negative electrode red hot, a very small amount of carbon dioxide is produced, too little to measure, but sufficiently great to cause a white precipitate with baryta water, and small specks of something black, presumably carbon, collect on the positive electrode.Several experiments were made with mixtures of hydrogen and carbon dioxide in the hope that perhaps the carbon monoxide a t the moment of its liberation from the carbon dioxide mould unite with the hydrogen to produce formaldehyde ; the presence of formaldehyde, how- ever, could not be detected, but the decomposition in a mixture of nearly equal quantities of carbon dioxide and hydrogen was considerably retarded. The residual gas was treated with caustic soda, ammoniacal cuprous chloride, and finally spongy palladium, There remained a very small quantity of gas. It could not have been ethylene for it was not altered by fuming sulphuric acid, but when mixed with oxygen it exploded feebly, and left a small quantity of gas soluble in caustic soda.Probably the gas was methane, but owing to the great difficulty in producing enough of it for analysis in a proper manner, the matter was left for the present. Moreover, the observation that carbon monoxide and hydrogen can be made to yield methane is not new, as Sir B. C. Brodie (Proc. Roy. Xoc., 1872, 21, 245) obtained 6 per cent. of this1068 COLLIE : DECOMPOSITION OF CARBON DIOXIDE. gas by sparking a mixture of carbon monoxide and hydrogen in a Siemens’ induction tube. The fact, however, that carbon dioxide is capable of being decom- posed to the extent OF 65 per cent. in the space of 10 seconds, when it is subjected a t low pressures to the electrical discharge from an ordinary induction coil, is of considerable interest, especially as it seems probable that the absorption of carbon dioxide by plants, and the subsequent liberation of oxygen when the plant is exposed to sunlight, may be due to this excessive instability of carbon dioxide when subjected to electrical strain.Tbat heat vibrations have much to do with the de- composition seems improbable, and the severance of the oxygen in carbon dioxide from the compound both in a vacuum tube by electrical energy, and in the plant by agency of light, may possibly be due to the same cause. It would be interesting to know whether the amount of oxygen evolved by growing plants in sunlight is equivalent to about two-thirds of the carbon dioxide absorbed, as this seems to be the point of equilibrium reached in the vacuum tube during either the decomposition of carbon dioxide into carbon monoxide or the union of carbon monoxide and oxygen, There has just appeared an interesting paper by Ciamician and Silber (Ber., 1901, 34, 1530), in which they show how light may play an im- portant part in chemical action, especially in the case when coloured substances, such as quinone, are allowed to react with easily dehydro- genised compounds such as alcohol, The reaction of quinone with alcohol is as follows : C2H60 = C,H,(OH), Many other carbonyl compounds were experimented with, and the same result obtained.The general reaction can be expressed thus : :CO + *OH = iC*OH + :O. Between this reaction and the assimilation of carbon dioxide in living plants which contain the coloured chlorophyll a close parallel can be drawn. The carbon dioxide, in presence of sunlight and the strongly coloured chlorophyll, breaks down into carbon monoxide (a free carb- onyl group) and oxygen. This carbon monoxide then reacts with the water in an exactly similar manner to that given in the equation above, :CO + H*OH = H*CHO + :O. and formaldehyde or formic acid is produced-or perhaps combination of carbon with carbon may take place, as is the case, according to Ciamician and Silber, when acetophenone is mixed with alcohol and exposed to sunlight. 2COMePh + C,H,O = CMePh(OH)*CMePh*OH + C,H,O.METAL-AMMONIA COMPOUNDS IN AQUEOUS SOLUTION. 1069 Carbon monoxide would first yield formaldehyde, H,CO, which, in presence of water, chlorophyll, and sunlight, might yield glycolalde- hyde, 2:>co + H,O = E>C(OH)*CHO + H,O, and by polymeric condensation the glycolaldehyde would yield sugars. RESEARCH LABORATORY OF THE PHARMACEUTICAL SOCIETY OF GREAT BRITAIN.

ISSN:0368-1645    

DOI:10.1039/CT9017901063

出版商:RSC    

年代:1901

数据来源: RSC

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METAL-AMMONIA COMPOUNDS IN AQUEOUS SOLUTION. 1069 CXI. -Metal-Ammonia Compounds in Aqueous Solu- tion. Part III. Salts ofthe Alkaline Earth Metals. By H. M. DAWSON and J. MCCRAE. DRY calcium chloride forms with ammonia a complex salt, but we have no direct evidence that this complex is capable of existence in solution. Raoult (Ann. Chinz. Phys., 1874, [v], 1, 263) has shown that the solubility of ammonia in concentrated calcium nitrate solution is greater than in pure water, and Konowaloff (J. RUM. Phys. Chem. Soc., 1899, 31, 985; CAem. Centr., 1900, i, 938) has found that the partial pressure of ammonia over an ammoniacal solution of calcium chloride is less than that over a pure aqueous solution of the same concentra- tion. Konowaloff's observation has been confirmed by Gaus (Zeit.anmg. Chem., 1900, 25, 236). There is in these results an indication that the dissolved calcium salt (the calcium ion) is capable of fixing ammonia. We have extended our experiments on the distribution of ammonia between aqueous salt solutions and chloroform to solutions containing salts of the alkaline earth metals, I n our first communication (Trans,, 1900, 77, I250), we have given results with calcium chloride, but these are to be regarded as preliminary experiments. The method of experimentation has already been sufficiently described (this vol., 495). The experiments were carried out at 20°, and the results given on p. 1070 have been obtained : If these results are compared with those obtained for the salts of the alkalis on the one hand, and with the salts of copper, zinc, cadmium, and nickel on the other, it will be observed that, speaking generally, the salts of the alkaline earth metals occupy a position between these two groups.In general, the absorptive power of solu- tions of the alkali metal salts for ammonia is less than that of pure1070 DAWSON AND MCCRAE : METAL-AMMONIA COMPOUNDS IN strength of aqueous solution. Concentra- tionof NH,ii the aqueous litre. grams part, per I I Calciuiii chloride : 1-0 1.0 1 '0 1 '0 0 -8 0 '4 0-2 0.2 1'0 1 *o 8-340 6.739 5 -045 8'525 8.574 8.534 8.516 8.523 11 '790 14-970 0.297 0.241 Strontium nitrate : 4.959 8-287 Barium bromide : Barium chloride : 1.0 0 -8 0-4 0.8 0.8 0.8 0.4 8 '284 8 *305 8.307 3.290 4'882 9'871 13.303 Concentra- tion of NH, in the CHCI,, gram per litre.c2. 0.3031 0.3090 0 '31 52 0.3175 0.3177 0-4201 0'5443 0.31 72 0.2535 0'1892 0.1894 0.3204 0.3293 0.3279 0.3263 0.1290 0'1912 0'3971 0'5298 Coefficient, C2 k'. - cl. 28.13 27'74 27.97 26.82 26.82 28-05 27.51 26.29 26'59 26-67 26-18 25.86 25.15 25.33 25.46 25-51 26-14 24.85 25.11 2oeScient foi pure water when concen tration of NH, in CHCI, is c2. k. 26.24 26.23 26'22 26 *22 26 '22 25 -96 25.65 26 *22 28-26 26.30 26 *30 26.21 26'19 26.19 26.19 26-33 26.29 26 *03 25-73 k-k' -. n - 1-89 -1.89 - 2'12 - 3-00 - 3 '00 - 2-09 - 2.02 - 0.07 - 0.31 - 0.37 + 0.40 1 '45 + 1 '06 1 -07 1 *82 1 -02 1'45 1.47 1'42 water, and we have already shown that thia diminution of absorptive power is approximately proportional to the concentration of the dis- solved salt, The influence of these salts waB found to be greatest for potassium salts, and least for lithium salts, the order of magnitude being potassium, sodium, ammonium, lithium.The experimental data represmt the superposed influences of physical action and the forma- tion of chemical complexes, and from the negative values obtained forAQUEOUS SOLUTION. PART 111. 1071 - k' with some of the lithium salts we conclude that in these cases the fixation of ammonia in the form of chemical complexes more than counterbalances the lowering of the absorptive power which would result from the purely physical action of the dissolved salt, The alkaline earth metals approximate in their behaviour to the alkali metals. For the barium salts investigated, the physical action preponderates, whereas in the case of the calcium salt, this physical action is more than counterbalanced by the formation of complex calcium-ammonia ions.These two opposed actions are of approxi- mately equal magnitude for the strontium salt investigated, and in consequence, the value of the distribution coefficient differs but little from that for pure water and chloroform. The arrangement of the alkaline earth metals in the series barium, strontium, calcium, corresponds with that of the series given above for the alkali metals. The tendency to form complex ammonia ions on the part of calcium is greater than that observed in the case of any of the alkali metals, but it is still very small in comparison with that found for the metals copper, zinc, cadmium, and nickel, k' was found to be constant for the The value of the expression - alkali salt solutions when both the salt and the ammonia concentra- tions varied.This constancy is in harmony with the conception that the preponderating action of the dissolved salt is of a physical nature. When the formation of ammonia complexes is very considerable, as with copper, zinc, cadmium, and nickel salts, then this expression is by no means constant. Examination of the previous table shows that - k' is not nearly so constant as in the case of the majority of the alkali salt solutions investigated, and this is probably explainable by the greater tendency towards the formation of ammonia complexes exhibited by the calcium, strontium, and barium salts. Finally, we may compare our results with those arrived a t by Konowaloff (Zoc.cit.) and by Gaus (Zoc. cit.). Konowaloff's results were obtained by determining the partial pressure of normal ammonia solution containing 1 gram-equivalent of salt per litre at 60°, and those of Gaus by determining the same at 25' with solutions which were normal with respect to ammonia and 0.4 normal with respect to salt. The following table contains the values of P, - P, P, being the ammonia pressure over pure water, and P that over the salt solution. For the comparison we make use of an approximate value of ____ which is a mewure of the total action. In k - n n k - k' n1072 DAWSON AND MCCRAE : METAL-AMMONIA COMPOUNDS IN BaCl,. SrCl,. Sr(N03),. CaCI,. 2 2 2 2 Konowaloff., ............. P l - P +1.05 -1.1 -1.2 -3.6 Gaus .................... P, - P - 0.02 -0.29 - -0.77 Distribution method ... - + 1.3 - -0.3 - 2.0 k - k ' n The agreement between the three series is as close as might be ex- pected, the only anomaly being that Gaus finds for barium chloride a negative value, whilst the experiments of Konowaloff and ourselves give a positive value. THE YORKSHIBE COLLEUB, LEEDS.

ISSN:0368-1645    

DOI:10.1039/CT9017901069

出版商:RSC    

年代:1901

数据来源: RSC

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1072 DAWSON AND MCCRAE : METAL-AMMONIA COMPOUNDS IN CXI1.-Metal-Ammonia Compounds in Aqueous Solu- tion. Part IV. The influence of Temperature on the Dissociation of Copper-Ammonaa Sulphate. By H. M. DAWSON and J. MCCRAE. IT has already been shown (this vol., p. 496) that the distribution of ammonia between water and chloroform at 20° is not quite independent of the concentration, and the variation is exhibited by the distribution coefficient curve on p. 497. In our first communication (Trans., 1900, "7, 1239), we have shown that a complex compound, probably Cu4NH,*S04, is formed when excess of ammonia is added to a solution of copper sulphate ; this complex compound is dissociable, and only when there is a large excess of ammoriia in the solution does the number of fixed ammonia molecules per atom of copper approximate to four.We have been able to follow the extent of this dissociation a t constant temperature with decreasing total ammonia concentration, and now we have endeavoured to ascertain the influence of temperature on the dissociation. On account of the method which we employ, it was impossible to use a temperature much above the ordinary, and we have not deemed it advisable to work above 30°, which is our upper limit. For lower temperatures, we are only limited by the freezing point of the solution, but the lowest temperature at which we found it convenient to work was 109 This gives us a range of ZOO, and it was expected that the extent of dissociation at the lower and higher temperatures would be sufficiently different to indicate the temperature influence.AQUEOUS SOLUTION.PART IV. 1073 Diatribution of Ammonia between Water and Chloroform at varying Temperatures. The method of experimentation was exactly as has been described in our previous communications (Zoc. cit.). I n order to ascertain the amount of ammonia fixed by the salt in solution from the distribution coefficient determined with this solution, i t is necessary to know the dis- tribution ratio between pure water and chloroform, and since this varies very considerably with the temperature, determinations of the latter had to be carried out at different temperatures. The temperatures chosen were 10' and 30°, and the following results were obtained : Concentration of NH, in aqueous part. Grams per litre. Temperature 10" : 5'211 6'974 8.123 8-701 12'835 17'370 17'428 Temperature 30" : * 6 '092 6.658 8.497 10 -203 11 '660 13.601 16.660 Concentration of NH, in the chloroform. Gram per litre.0-1686 0.2261 0'2633 0'2847 0.4253 0,5864 0.5862 0.2250 0.2949 0,3761 0'4558 0'5232 0'6133 0.7575 Distribution coefficient, - C1. c1 k. 30.91 30'84 30 734 30'57 30 *I 8 29'67 29.73 22'63 22.57 22.65 22-39 22 29 22.18 22-00 * In a previous publication (Trans., 1900, 77, 1243), we have given the co- efficient at 30" as 23'2, but we prefer to take the numbers given above for the reason pointed out on p. 496. These figures show exactly the same relationships as those previously obtained for the distribution coefficient at 20° (this vol., p. 496), namely, for solutions less than 0*5 normal with respect to ammonia the distri- bution coefficient remains practically constant at constant temperature, but with more concentrated solutions this ratio diminishes with increas- ing concentration of tbe ammonia.The variation of the distribution coefficient within the same limits of ammonia concentration is very nearly the same at the three temperatures, consequently the curve1074 DAWSON AND McCRAE : METAL-AMMONIA COMPOCNDS IN given on p. 497 may be used to express the results obtained at 10' and 30' if we add to the ordinate 4.54, or subtract from it 3.66. I n other words, the three curves representing the dependence of the dis- tribution coefficient on the ammonia concentration at the different temperatures are almost parallel. It is evident that the distribution coefficient at constant ammonia concentration is not a linear function of the temperature, for the difference in the coefficient €or loo (from 20° to 30°) is in one case 3.66 units, whilst in the other case, for loo (from 10' to 20°), it is 4.54. The results obtained have been plotted as curves (not reproduced here), and from these the values at any concentration of ammonia can be read off.Experiments at 10' and 30° with Copper Sulphate Solutions. A t 10Oand 30°, experiments were made with 0.1 normal copper sul- phate solutions, and at 10' with 0.05 normal solutions. The results so obtained are recorded below, and they may be compared with those which we have previously found at 20°. In the table on p. 1075 we give the various data, the molecules of ammonia fixed per molecule of salt (or per atom of copper) being cal- c , - h 2 culated from the formula, 17,07? 2 in which k is the distribution coefficient for pure water at the same concentration of ammonia in the chloroform, c1 and c2 the observed ammonia concentrations in the aqueous and chloroform layers, and n the normality of the salt solu- tion.We are unable to take account of the physical action of the dissolved material, but, as already stated (p. 511), we believe this to be, in the case of coppermdts, very small. When the distribution coefficient attains a high value, correspond- ing to a small amount of free ammonia in the salt solution, the error in the determination of the fixed ammonia may be relatively large on account of the small quantity of acid used in the titra- tion of the chloroform.Further, if the coefficient is not much greater than that for pure water, the accuracy is not great, since the calculation involves the difference between these two values. The most accurate values are those obtained when the concentration of ammonia in the aqueous phase is between 6 and 9 grams per litre. As no extreme accuracy can be claimed for the individual figures, we have drawn smoothed curves representing the molecular amount of ammonia fixed per atom of copper in 0.1 N solution at loo, 20", and 30" with varying ammonia concentration. The numbers for 20' have been recalculated in accordance with the later determina-AQUEOUS SOLUTION. PART IV. Concentration of NH, in aqueous layer. Grams per litre.C1' 1075 Concentration of NH, in CHCI,. Gram per litre. c2' Temperature 10". 0.1 N copper sulphate : 5-427 6.688 7'171 8-931 10.675 13.130 8-322 0.0765 0.1153 0.1317 0.1679 0.1872 0.2446 0.3273 0-05 N copper sulphnte : 3.580 5.347 7.095 9'800 0.0666 0.1224 0*1786 0,2679 Temperature 30: 0.1 N copper sulphate : 5.347 7.062 8'650 10.310 11.960 13-720 0.1072 0.1790 0.2441 0.3170 0 '391 5 0'4699 Distribution coefficient. k'. 70.92 58.01 E4.45 49 *56 47.71 43.65 40.12 53.76 43'68 39.73 36-58 49 *86 39-45 35.44 32.55 30.55 29-21 Coefficient corresponding to c2 for water. k. 30'94 30.91 30.89 30'88 30.87 30.82 30.57 30.94 30.90 30.87 30.75 22'W 22.64 22.62 22-60 22.52 22-39 Molecular ratio fixed NH,. 17-01 n of cuso,: e, -kc, 2,- 1 : 3.52 3 '66 3'64 3'69 3.67 3 '66 3'68 3 '56 3 '66 3 '70 3.66 3 '42 3'53 3'66 3-68 3.68 3-76 tions of the distribution coefficient between pure water and chloro- form at this temperature.Instead of reproducing these curves, me have constructed the table given on p. 1076 indicating points on the curves. As would be expected, the figures indicate that, at constant ammonia concentration, the extent of dissociation increases as the temperature rises, and it may be stated that if a comparison be made between the numbers obtained with 0.05 Ncopper sulphate solutions at loo and 20°, the same concluaion is evident. The differences between the numbers obtained at the different temperatures are, however, too small to admit of any quantitative statement as to the influence of1076 MELDOLA AND EYRE: 6 grams per litre ............ 7 , , , , ............ a , , , , ............ 9 , , , , ............ Table showing the number of molecules of ammonia Fxed per atom of copper in 0.1 N solution. 3.55 3'63 3'67 3.70 Concentration of NH, in the aqueous phase. 10". 20". 3 '46 3.55 3 '61 3.67 1 30". -I 3'42 3 *51 3 '58 3-62 temperature on the dissociation of the complex copper ammonia sulphate. THE YORKSHIRE COLLEGE, LEEDS.

ISSN:0368-1645    

DOI:10.1039/CT9017901072

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年代:1901

数据来源: RSC

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1076 MELDOLA AND EYRE: CXII1.-Additional Notes on Dinitloo-o-anisidine. A Chemical Reaction in which one of the Products continues the same Reaction. By RAPHAEL MELDOLA, F.R.S., and JOHN VARGAS EYRE. THE dinitroanisidine described last year by one of the authors and Elkan Wechsler (Trans,, 1900,77,1172) has been since shown to have the constitution 4 : 5-dinitro-2-aminoanisole (Proc., 1901, 1’7, 131 ; also Freyss, Bull. SOC. had. Mulhouse, 1901,70, 375). Further evidence of this constitution is given in the following paper as well as some experiments which throw light on the remarkable action of nitrous acid on the compound. The Diphenyhxines from the Triaminomisole and its Acstyl Dsrivatives. Dinitroacetnnisidide (m. p. 1 62-163O) was reduced in glacial acetic acid solution with zinc dust and a few drops of hydrochloric acid to start the reaction. The solution containing tbe acetyltriaminoanisole was mixed with an acetic acid solution containing the calculated quantity of benzil, and the mixed solutions heated for some hours on a water- bath.The azine is thrown out on dilution with water, and neutralisa- tion with ammonia as an ochreous powder which dissolves in boiling alcohol with a brownish colour. The solution is slightly fluorescentADDITIONAL NOTES ON DINITRO-0-ANISIDINE. 1077 when cold, awl the azine separates in the form of ochreous needles melting at 823-224". 0.1 163 gave 11.8 C.C. moist nitrogen a t 20.5"and 764 mm. N = 11.62. 0.1186 ,, 11.75 ,, ,, 19.5O ,, 752.4 mm. N = 11-33. C,,H,,O,N, requires N = 11.39 per cent. The dinitroanisidine on siiiiilar ti eatment gave an azine cryst allising from alcohol in brown needles with serrated edges, and from benzene, in which i t is very soluble, in minute, p,de, ochreous needles.The melting point is 194-195". 0.1092 gave 12.2 C.C. moist nitrogen at 18.5Oand 755.S mm. N = 12-78. 0.0903 ,, 10 $ 9 9 , 20.5" ,, 770.5 mm. N = 12.80. C2,HI7ON, requires N = 12*S4 per cent. The dilute alcoholic solution of the azine has a distinct green A UoreFcence which disappears on heating, and reappears on cooling. The compound is basic and dissolves in strong hydrochloric acid with a claret red colour, which disappears on dilution with water, owing to the dissociation of the salt. The constitution of these compounds is shown by the formulae : NH A~()N : ~ c , H , NH,<)N : ~ c , H , C€I,*O\/N :C*C,H;* C! Li3*O\/N:C*C,H,* The mine ring may of course be represented in the usual way with a cross linking between the nitrogen atoms : or the left- hand benzene ring may be written on the quadrivalent (quinonoid) type : :N*E*C,H, :N*C*C,H; *r *g*C,H, *N.C*C,€I,' Quctnlhtive Diaxotiscdion of L)initi*o-o-anisidine.It has been proved in former p p e r s that this compound loses a nitro-group on diazotisation, and we have shown in our last note (Proc., 1901, 17, 131) that the nitro-group thus eliminated i s the one occupying the para-position with respect t o the amino-group, the resulting compound being a diazoxide. I n the note referred to, we suggested that the nitro-group might be eliminated in the form of nitrous acid according to the scheme : N02*C,H,((>CH,)< N;O NO, H -+ N02-C,H2(OCH,)<f? - .If this view were correct, me should have the somewhat remarkable case of a chemical reaction in which one of the products (nitrous acid) V O I . L X X J X . 4 D1078 MELDOLA AND EYRE. is the same a s the reagent added, and is thus capable of carrying on the diaaotisation. ID order to submit this to the test of experiment, a method had to be devised for measuring quantitatively the amount of diazotising work done by a known quantity of nitrous acid. Pre- liminary experiments with a standardised solution of sodium nitrite, and fiolutions of known strength of dinitroanisidine in glacial acetic acid, showed that the ordinary method of ascertaining the end of diazotisation by the liberation of free nitrous acid was quite inapplic- able in the present case.Free nitrous acid, as shown by the potassium iodide and starch test, shows itself from the very first addition of the nitrite solution, and does not cease to be present until after some days. I n other words, the diazotising process has no time limit sharp enough to be fixed by any colour test. 'Under these circumstances, we were led to use the gravimetric method formerly applied with success in the case of the quantitative resolution of the diazoamido-coinpounds (Meldola and Streatfeild, Trans., 1887, 51, 438 ; 1888, 53, 675). The method as applied to the present reaction depends upon the following conditions : I f sodium nitrite solution is added to an acetic acid solution of dinitroanisidine, keeping the latter in excess, there are present after a certain interval (1) diazoxide, (2) unaltered dinitroanisidine, and (3) nitrous acid.After a sufficiently long interval (about 3 days), free nitrous acid is no longer detectable, but even if free nitrous acid is present this does not interfere with the results. On adding such a solution to an alkaline solution of P-naphthol, the diazoxide combines at once to form the azo-compound, N02*C6H2( OCH,) (OH) *N2* ~loH6*oH.* On making strongly acid with hydrochloric acid, the free azo-compound is precipitated, whilst the unaltered dinitroanisidine remains in solu- tion if a sufficient volume of water is present. The azo-compound, being practically insoluble in water (even when hot), can be collected on a tared filter, washed with dilute acid, and finally with hot water, until free from all soluble compounds, and then dried and weighed.The weight of azo-compound gives the weight of diazoxide formed. Two sets of experiments mere made, using the following quantities : A.-First Set.-Twenty-five C.C. of a 1 per cent. solution of dinitru- anisidine in acetic acid. Sodium nitrite solution 1 C.C. = 0.0029 gram NaNO,. Nitrite solu- tion 1 C.C. = 0*00906 gram NaNO,. B.--Xecond 8et.-Same quantities of dinitroanisidine. * The formula of this compound given in the preliminary note (Trans,, 1900, 77, 1173) does not represent it as containing a hydroxy- as well as B methoxy-group, because the nature of the reaction had not been a t that time fully made out. The percentage of nitrogen does not differ considerably in the two cases.ADDITIONAL NOTES ON DINITKO-O-ANISIDINE.1079 The quantity of dinitroanisidine was the same throughout, 0.25 gram, and the same quantity of nitrite, 0.0202 gram, was added in each case, namely, 6.98 C.C. in set A, and 2-23 C.C. in set B. This quantity of nitrite is onefourth the calculated quantity required on the assump- tion that one molecule of dinitroanisidiiie requires o m molecule of nitrite. The results are given below : Dinitro- anisidine. Weight of 1 Weight of 1 Nitrite' 1 &naphthol. azo-compound. * f I ... 0.25 I 4 d R V S I 0'0202 ' 0.3498 028C7 1 0.3195 9 2 1 0'3bO6 v ... I 9 1: ~ 0.3694 9 , I I 9 2 ... I r: I The P-naphthol is slightly in excess of that required by theory, namely, 0.2 instead of 0.17 gram, but this excess is completely re- moved during the treatment.The quactity of azo-compound thcoreti- cnlly producible by the weight of nitrite taken (0.0202 gram) is 0.0992 gram, The weight of azo-compound theoretically producible on the assumption that all the dinitroanisidine is converted into diazoxide is 0.3968 gram. Thus che results show t h a t whilst the theo- retical limit of diazotisation is not reached in five days, the actual amount of diazoxide formed is greatly in excess of that capable of being produced by the weight of nitrite added. The nitro-gyoup eliminated t Jt,us continues the diaxotisation. The method, although not claiming to give results within very close limits of accuracy, is sufficiently exact to bring out this main conclu- sim in a very striking manner. The only sources of error that can be foreseen are the solubility of the azo-compound in water leading to a deficiency and the possible retention of dinitroanisidine leading to an excess in weight. The first of these errors we believe to be quite negligible. The second was provided against by washing the azo- compound (after being collected) off the filter, redissolving in hot dilute sodium hydroxide, reprecipita ting by acid, and collecting and washing again before drying and weighing. The azo-compound in each experi- ment was thus twice precipitated from a large volume of dilute acid, and although a slight loss may have been incurred by this treatment, the final product was pure azo-compound as shown by analysis. 0.1174 of No. I1 gave 12.85 C.C. moist nitrogen a t 21° and 757.4 mm. N = 12.40. C,7H1,0,N3 requires N = 12.39 per cent. FINSBURY TECHNICAL COLLEGE. 4 ~ 2

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DOI:10.1039/CT9017901076

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年代:1901

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1080 GORDAN AND LIMPACH : RELATIONS BETWEEN PHYSICAL CXIV .-Some relations between Physical Constants nnd Constitution in Benxenoid Amines, Paint 11. BY PAUL GORDAN and LEONHARD LIMPACH. THIS paper is a continuation of the discussion of the relationship between " Melting Puints and Constitution i n some Amines " on which a preliminary note wag published in 1893 by W. R. E. Hodgkinson and L. Limpach (Proc., 9, 41). By replacing the benzenic hydrogen in formoanilide and acetanilide by methyl, 38 compounds can be obtained. If the number of intro- duced methyl groups be p, then the values 0 : 1 : 2 : 3 : 4 : 5 * represent the number, p, of the anilide, toluidides, xylidides, and amino-tri- methyl, -tetramethyl, and -pentamethyl derivatives respectively. The melting points of 36 of these 40 compounds have been actually determined, and are given in Table 1.This series, R, comprises 1 : 3 : 6 : 6 : 3 : 1 compounds. TABLE 1. ~~ ~ ~~ ~ Formyl conipouiids. Formnnilide [O] .......... 46" Formotoluidides. 1 ................................ 2 , ................................ 3 ................................ Fo: tilosylididcs. 1 : 2 ............................. 2 : 3 ............................. 1 : 5 ............................. 1 : 3 ............................. 2 : 4 ............................. 1 : 4 ............................. 58" liquid 52" 103'5" 68 164 113.5 76.5 116.5 Acetyl compounds. Acetnnilide [O] ............... 114" Acetotoluidides. 1 ............................... 107" 2 ................................. 65.5 3 ................................. 147 Act:toxyliclides.1 : 2 ............................ 134O 2 : 3 ............................ 99 1 : 5 ........................... 177 1 : 3 ............................. 129 2 : 4 ............................. 142'5 1 : 4 ............................ 138.5 * As a matter of couvenience, the positions in formanilide are numbered thus : NH*CHO so that positions 1 and 5 are relatively ortho to the formyl or acetyl groups respectively.CONSTANTS AND CONSTITUTION IN BENZENOIL) AMINES. 1081 TABLE 1 (continued). Formyl compounds. Forrnanilicle [0] .. . ... ... .. . 46" Formylaminot rimethylbenzenes. 1 : 3 : 5 ........................ 2 : 3 : 5 ..... ................. 120'5 1 : 2 : 4 ..................... $8 1 : 4 : 5 ........................ 1 : 2 : 3 m .. . . . . . . . . . . . . . . . . . . . . . 2 : 3 : P ............... ......... 176" 98.5 Formylan~inotetrainethylbenzenes. 1 : 2 : 3 : 4 ............... .,.... 1 : 2 : 4 : 5 ..................... 164 143.5" i : 2 : 3 : 5 ..................... 183 Formylaminopentamethylbenzene. 1 : 2 : 3 : 4 : 5 ...,........... 216.5" Acetyl compounds. Acetanilide [O] ... ,. . . . , . . . . . , 114" Acetylami no trime th yl benzenes. 1 : 3 : 5 ....................... 216'5" 2 : 3 : 5 ......... ..,........,.. 164 1 : 2 : 4 ........................ 126 1 : 4 : 5 ........................ 1 : 2 : 3 ................ * ....... 2 : 3 : 4 ........................ 164.5 ~~ Acetylaminotetrame thylbenzenes. 1 : 2 : 3 : 4 ..................... 1 : 2 : 3 : 5 ......,............. 215'5 1 : 2 : 4 : 5 .. ... .. .... ... ... ... 169" 192 Acetylaminopeiitamethy lbenzene. 1 : 2 : 3 : 4 : 5 ........,....... 215.5" The first step in the investigation was to obtain such an arrangement of these 36 melting point values that certain regularities should appear. Averages D, and D, were found for the series R. The values D, of series R are obtained by adding all the melting point values of the compounds and dividing by the number of com- pounds. The values D, by adding the highest and lowest melting points and dividing by 2. It will be observed from Table 2, firstly, TABLE 2, Compounds. I'ormxnilide . . . . . . . . . . . . . . . . . . . . . . . . . , , Formotoluidides . . . , . , . I . . . . . . . . . . . . . . . . . Formoxylidides . . .. . . . . . . . . . . . . . . . . . . . . . . Formylaniinotrimethylbenzenes . . . . . Formylaminotetramethylbenzenes . . Formylaminopentamethyl benzenes . Acetanilide.. . . . . ... . . . . . . ... .. . . . . . . . . . . . . Acetotoluidides . . . . . . . . . . . . . . . . , , , . . . . . . Acetoxylitlides . . . . . . . . . . . . . . . , . . . . . . . . . . Acetylaminotrimethylbenzenes . . .. Acctylaminotetramethylbellzenes .. Acetylaminopeiitamethylbenzenes . . 54'4 81 -6 108-8 136 163-2 190'4 47'6 81 '6 115% 149'6 183 -6 217'6 81% 108.8 136 163'2 190'4 217% 115% 136 156.5 176.8 197-2 217'6 46 107 163.7 216'5 114 106-5 136.7 192 215.5 D,. 46 116 163'2 216.5 114 106.2 138 171.2 192-2 215.51082 that the differences between D, and D, are small, and secondly, that they differ but, little from certain values, N, and N,, which are given and defined by the formulae : GORDAN AND LlMPhCH : RELATIONS BETWEEN PHYSICAL 4.6'8(p + 2) for formyl compounds.6'8(5p + 7) for formyl compounds. N,= { 4.6'S(p + 3) for acetyl N2= { 6'8(3p + 7) for acetyl ,, ,, The values of N,, N,, D,, D,, are shown in Table 2, and the differ- ences N, - N,, D, - N,, D, - N2, D, - D,, in Table 3. TABLE 3, Compounds. ~~ Formanilide.. ............................. Formotoluidides ........................ Formoxylidides ......................... Formylaminotrimethy1benze11es ..... Formylaminotetmmetliylbenzenes . Formylaminopen tamethy lbenzenes . Acetanilid e.. .............................. Acetotolnidides ........................ A cetoxylidides ..........................Acetylaminotrimethylbenxenes ..... Acetylaminotetramethylbenzenes .. Acetylaniinopentamethylbenzenes.. N2 - ivl* - 6.8 0 6'8 13 '6 20'4 27'2 34 27 '2 20'4 13'6 6-8 0 D1- NI. - 8'4 - 1.8 0.5 26 *1 - - -_ ._ 32 '4 0 -7 1.6 - 2'1 - 2'3 B1- A$. - ~ . - 1.6 - 7.9 - 19.9 - 1.1 -~ __ - 1.6 - 29.5 - 19.7 - 4.8 - 2'1 0 9 - 0.5 0 0 - 0'3 1 '3 0'2 0 The melting points of the 36 ccmpounds can be arranged in three primary classes (Table a), and the third class again can be divided into 2 sub-classes. The first class contains 6 formyl and 9 acetyl derivatives, the melt- ing points of which fall between the values N, and N,, or differ, a t most, about 2' from them. The second class comprises 2 formyl and 4 acetyl compounds, the melting points of which are more than 2 O higher than the values in N, and N,. The first of these compounds is p-acetotoluidide and all the others contain methyl groups substituted in the 1 : 5 positions.In the third class are 10 formyl and 5 acetyl compounds: their melting points are more than 2 O lower than indicated under N, and N,. Of these 15 compounds, 9 belong to the second sub-class, they contain methyl groups substituted in the 2 : 3 or 2 : 4 positions. The melting points of formyl derivatives differ more amongst them- selves than do the melting points of acetyl derivatives.CONSTANTS AND CONSTITUTIOK IN BENZENOID AMINES. 1083 Four compounds have very high melting points not differing more than 1' from 216'. TABLE 4. 1st Class. Formyl derivcbtives. [O] = 46' j [ 1 : 31 = 1 1 3.5" ; [ 1 : 41 = 1 1 6.5' ; [ 1 : 2 : 3 : 51 - 183' ; [l : 2 : 4 : 51 = 164O; [l : 2 : 3 : 4 : 51 = 216.5'.A cet y I derivatives. [O] = 114'; [I] = 107'; [1 : 21 = 134'; [l :4] = 138.5'; [2 :4] = 142.5O; [I1 : 2 : 3 : 4 : 51 = 215.5'. [Z : 3 : 51 = 164'; [2 :3: 41 = 164.5' ; [l : 2 : 4 : 51 = 192' 2nd Class. Formy! derivatives. [l : 51 = 164'; [l : 3 : 51 = 176'. 3rd Class. 1st Sub-class. liormyl derivatives. [l] = 5s' ; [2] = fluid ; [ 31 = 52' ; [l : 21 = 103.5". A cety l devivatives. [2]=65*5'; [I :3]= 129". 2nd Sub-class. Fomn yl der,ivatives. [2 : 31 = 68" ; [2 : 41 = 76.5"; [l : 2 : 41 = 9s"; [2 : 3 : 41 = 98.5'; [2 :3:5] = 120.5'; 11 : 2 : 3 :4] = 143.5'. Acetyl derivatives, [2:3]-99'; [I :2:4]=126'; [1:2:3:4]=169', As previously mentioned, 36 only of the 40 possible compounds of this class have had their melting points determined.Both the formyl- and acetyl-amino-1 : 4 : 5- and 1 : 2 : 3-trimethylbenzenes are missing.1084 PHYSICAL CONSTANTS OF BENZENOID AMINES. The melting points of these substances can be approximately calcu- lated. The differences, D, - N,, given in Table 3 are but small (with the exceptions of aniline and aminopentamethylbenzene, which give small differences D, - NJ. It may, therefore, be pretty safely assumed that for the two missing substances these numbers would also be small. On this assumption, we may take the average of D, as 136" for formylaniinotrimethyl- benzenes, and 170" for the corresponding scetyl compounds. For the formglaminotrimethylbenzenes, the average of D, may be taken as 5" higher than D,, so that D, may be about 141".I n Table 1, the lowest melting point of formylaminotrimethylbenzene is 98". The 1 : 4 : 5-modification contains the 1 : 5-arrangement, and has, probably, the highest melting point ; we have [I : 4 : 51 4- 9s" = D, = 141" and [I : 4 : 51 = 1 8 4 O . 2 The mean value of D, for the formylaminotrimethylbenzenes is 136", we have therefore : [ 1 : 3 : 5 ] + [ 2 : 3 : 5 ] + [ 1 : 2 : 4 ] + [ 1 : 4 : 5 ] + [ 1 : 2 : 3 ] + [ 2 : 3 : 4 ] = D, = 136'. Introducing the values from Table 1, 176" + 120.5" + 98" + 184" + [l : 2 : 31 + 98.5" = 1360, 6 from which we calculate for the 1 : 2 : 3-derivative the melting point 135". With the acetyl derivatives, the case is somewhat different : the one of constitution [l : 3 : 51 has the highest melting point of all, 216.5", and the 1 : 2 : 4-derivative the lowest, namely, 126".D, does not affect the melting points of the 1 : 4 : 5- and the 1 : 2 : 3-derivatives. Of these melting points, that of the 1 : 4 : 5-corn- pound is no doubt the higher, and the difference between them may be about 30". [l : 4 : 51 - [I : 2 : 31 = 30". By the formula [ 1 : 3 : 5 ] + [ 2 : 3 : 5 1 + [ 1 : 2 : 4 ] + [I : 4 : 5 ] + [ 1 : 2 : 3 ] + [ 2 : 3 : 4 ] - -- 6 D, = 170". Introducing the values from Table 1, 216~5"+164"+126"+[1 : 4 : 5 ] + [ 1 :2:3]+164*5" 6 = 170". -~ [l : 4 : 51 = 190". therefore [l : 4 : 51 + [l : 2 : 31 = 350" [1 : : 31 = 1600,ACTION OF DIASTASE AND YEAST ON STARCH-GRANULES. 1085 It will be seen from Table 1 that the melting points of the acetyl derivatives are higher than those of the correspondiug formyl com- pounds. This is more clearly shown in Table 5. TABLE 5. Constitn- tion. Aniline .......................... Tolnidine ........... ...........I 1 , , ...................... ,) ..................... Sylidine ........................ ,, ........................ ,, ........................ ,, ........................ ,, ..................... , , ...................... l i ~ ~ i i n o t ~ i ~ i i e t t ~ y l ~ ~ ~ ~ ~ ~ ~ i ~ e ... 9, ,, $ 1 , 1 Y , ,, 9 2 Y 9 9 , , 9 ... ... ... ... ... Aiiiiiiotetraiiiethylbcnze~ie 2 9 2 9 9 ) 7 ) Aminopen tnnicthyll)ei~zene 2 3 1 : 2 2 : 3 1 : 5 1 : 3 2 : 4 1 : 4 1 : 3 : 5 2 : 3 : 5 1 : 2 : 4 1 : 4 : 5 1 : 2 : 3 2 : 3 : 4 1 : 2 : 3 : 4 1 : 2 : 3 : 5 1 : 2 : 4 : 5 1 : 2 : 3 : 4 : 5 Formyl com- pound. 4 6" 58 liquid 52 103.5 68 164 113.5 76.5 116.5 176 120.5 98 184 135 98-5 143.5 183 164 216.5 Acetyl com- pound. 11 3-1 14" 107 147 134 99 177 129 142'5 138-5 216'5 164 126 190 160 164-5 169 215.5 192 215.5 65.5 67" 49 95 30 -5 31 1 3 13-5 66 22 40.5 43-5 28 6 25 66 25 -5 32.5 28 -I ERLAKGEN.

ISSN:0368-1645    

DOI:10.1039/CT9017901080

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年代:1901

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ACTION OF DIASTASE AND YEAST ON STARCH-GRANULES. 1085 CXV.-The combined Action o f Diastase and Yeast on Starch-grctnules. By GEORGE HARRIS MORRIS, Ph.D., B.Sc. IT has long been known that when starch conversions, containing high type malto-dextrins or the so-called stable dextrin, are acted on by yeast in the presence of diastase, the action is very greatly in excess of that produced by either yeast or diastase acting separately; in fact, the so-called stable dextrin, which is not acted on either by yeast or by diastase under ordinary conditions, may be completely fermented by yeast in the presence of active diastase. Some experiments described a few years ago by J. Vuylsteke (BUZZ. Acccd. roy. Belgipue, 1892, [iii], 24, 577), in which he showed that certain starches, in the solid state, might be ferment,ed by j e a s t in the presence of malt extract, led me to examine the question whether, in1086 MORRIS: THE COMBINED ACTION OF this case also, the combined action of yeast and diastase exceeded that of either when acting alone.To this end, 100 grams of barley-starch were digested with 50 C.C. of normal cold water malt extract and 250 C.C. of water, with constant agitation in a Dunstan’s laboratory shaking machine. Side by side with this, the same quantities of starch, malt-extract, and water were digested with the addition of 10 grams of washed and pressed yeast, the gas evolved being passed through a small wash-bottle. A t the end of 72 hours the two experiments were stopped, in the first the residual starch was filtered off, and the specific gravity, the optical rotation, and the cupric reducing power of the filtrate determined in the usual way ; in the second, the residual starch and yeast were also removed by filtration, the alcohol in the filtrate determined by distillation, and the specific gravity, the optical rotation, and the cupric reducing power determined in the residue after making up t o the original volume.The results obtained were* : (a) Barley-starch with malt-extract alone. Specific gravity ...................................... 102 1 -6. Optical activity in 100 mm. tube .................. 20.7 divisions. Cupric reducing power on 100 C.C. ............... 6.198 grams CuO. (b) Barley-starch with malt-extract and yeast. Alcohol per 100 C.C. ...............................7-95 grams. Specific gravity of residue Optical activity in 100 mm. tube .................. 2-4 divisions. Cupria reducing power on 100 C.C. .............. 0.8624 gram CuO. Control experiments were made in each case with malt-extract alone, and the above numbers are corrected for the results so obtained. When the excess specific gravity of the filtrate in (a) is divided by 3.934, the divisor for maltose a t this density, it is found that the solid matter in solution per 100 C.C. is 5-490 grams; calculated from the optical activity, the quantity per 100 C.C. is 5.201 grams, and from the cupric reducing power, 4.608 grams per 100 C.C. These numbers are su5ciently close to allow of the conclusion that the substance in solution is maltose, and on the basis of the specific gravity, we find that 16.470 grams have gone into solution in the 92 hours.This corresponds to the dissolution of 15.6 per cent. of the starch employed. I n the second experiment (b) in which diastase (malt-extract) and * For a description of the methods used, see ‘‘ Experimental methods employed in the examination of the products of Starch-hydrolysis by Diastase ” (Brown, Morris, and Millar, Trans., 1897, 71, 72-108). ........................ 1007.27.DIASTASE AND YEAST ON STARCH-GRANULES. 1087 yeast were allowed to act conjointly, the amount of alcohol formed by the fermentation corresponds to 15.437 grams of maltose fermented per 100 c.c., and the cupric reducing power of the residue to a further 0.624 gram of maltose per 109 c.c.; the optical activity required by this amount of maltose is 2-48 divisions, against 2.4 obPerved.The specific gravity of the residue indicates the presence of 1 *85 grams of solid matter per 100 c.c., but as this includes the non-volatile products of fermentation i t does not correctly represent the soluble products directly derived from the starch. The soluble products in this case may therefore be taken as 15,437 + 0.624 = 16.061 grams per 100 c.c., or 48.183 grams in all. This means that 45.6 per cent. of the starch had been decomposed. There W H S therefore a greatly increased action of the diastase in the presence of yeast, the quantity of starch which went into solution being nearly three times the amount dissolved by tho diastase alone. It appeared possible that this increased action might be due to the removal by fermentation of the soluble starch-products first formed by the action of the diastase on the starch-granules, thus allowing the enzyme t o act more freely on the remaining granules.Opposed t o this, however, mas the consideration that the alcohol formed during fermentation would probably exercise as great a retarding influence on the diastase as would the soluble starch-products. I n order t o examine this possibility, 10 grams of barley-starch were shaken with 25 C.C. of cold water malt-extract and 100 C.C. of water, side by side with similar quantities of starch and malt-extract, but with the addition of 100 C.C. of a solution of starch-products in place of the water. After 24 hours, both mixtures were filtered and ex- amined as described above. It was found that there was only a difference of 0.24 gram per 100 C.C.in the quantity of starch dissolved in the two experiments. This point was further tested by taking 20 grams of barley-starch, mixing i t with 50 C.C. of cold water malt- extract and 200 C.C. of water, and solidifying the whole with 3 per cent. of gelatin. The mixture was divided into two portions, one being allowed t o stand for 24 hours, and the other placed in a dialys- ing tube, surrounded with distilled water, for 24 hours. At the end of that time, the two experiments were examined as before, and it was found t h a t the amount of substance dissolved in the first experiment was exactly the same as the sum of the soluble products remaining in the dialysing tube plus the maltose which had diffused into the water surrounding it.In the first, the density of the solution, after making all due corrections, was 1010.0, in the second, 1010.1 (water = 1000). It then appeared desirable to ascertain (a) whether the presence of yeabt, under conditions which prevented the exercise of its fer- mentative power, had a n effect similar t o that which i t exerted when1088 MORRlS: THE COMBINED ACTION OF able t o ferment the soluble products formed by the diastase, and (6) whether any increased activity was conferred on the diastase of the malt-extract by the vital activity of the yeast during fermentation. With this end in view, a series of three experiments was made. In (1) 10 grams of barley-starch were digested with 25 C.C.of malt- extract, 100 C.C. of water, and 2 grams of washed and pressed yeast for 24 hours; in (2) the same quantities of starch, malt-extract, yeast, and water were digested in the shaking machine for 24 hours in the presence of a small quantity of chloroform, in order to check the fermentative activity of the yeast ; and in (3) 25 C.C. of malt-extract were mixed with 100 C.C. of water and 2 grams of yeast and allowed to stand until the fermentation was complete. The liquid was then filtered, and the clear filtrate digested with 10 grams of starch in the shaking machine for 24 hours. After each experiment had proceeded for 24 hours, the residual starch was filtered off, and the filtrates examined as described above. In (1) and (3) the ‘‘ original gravities” * were determined and com- pared with the specific gravity of the solution in (2).The results were as follows : (1) ‘‘ Original gravity ” ......... 1010.34 (2) Specific gravity ............... 1005.29 (3) “ Origiual gravity ” ......... 1006.50 These experiments show that neither the presence of non-fermentative yenst-cells nor the influence of fermentation on the diastase of the malt-extract had the effect of bringing about the dissolution of the Same amount of starch as had the combined action of malt-extract and active yeast. I n all these experiments, the matter in solution, or remaining in solution unfermented, had an optical activity and cupric reducing power corresponding to the presence of maltose only. A furthur experiment wm made to determine whether agitation alone had any influence on the action of diastase on starch-conversion products.For this purpose, a solution of transformation products of high rotatory power was made by converting a starch paste with malt-extract in the usual way. After boiling and filtering the solution, it was divided into two portions, to each of which 5 C.C. of cold water malt-extract per 100 C.C. were added. One portion was shaken for 24 hours, the second was allowed to stand without agitation for the same period. The solutions were then analysed, and found t o be identical * I t is more convenient to express the matter dissolved in this way, since the alcohol, &c., produced by the fermentation of the malt-extract itself can be more easily corrected forDIASTASE AND YEAST ON STARCH-GRANULES.1089 in composition. Agitation, therefore, is without any influence on the action of diastase. Finally, the action of precipitated diastase was compared with that of malt-extract. The experiments were carried out precisely as those first described, with the exception that 50 C.C. of a solution of diastase (containing 0.1 gram of precipitated diastase) mere used in place of cold water malt- extract. I n the experiment with diastase alone, the quantity of matter which went into solution in 24 hours was comparatively small, amounting only to 0,402 gram per 100 c.c., but when the diastase and yeast acted together, the quantity dis5olved was 2.37 grams per 100 c.c., and of this 1.59 grams were fermented. There is therefore a still more marked difference between the action of precipitated diastase alone and that of diastase plus yeast, than in the corre- sponding experiments *where cold water malt-extract mas employed, although in neither instance is the action so considerable or so rapid.The analysis of the matter which went into solution under the action of diastase and of that which remained unfermented points t o it being a mixture of maltose and dextrin, and not maltose only, as is the case when malt-extract is employed. Only those starches, the granules of which are attacked by diastase in the cold, undergo fermentation in the presence of diastase and active yeast; thus potato starch, the granules of which are not attacked or dissolved by malt-extract alone, remains absolutely un- touched by malt-extract and yeast when acting together, The foregoing results are especially interesting in view of the attention which has of late been given to instances of so-called sym- biotic action between moulds and yeasts, the chief action of the former being apparently to secrete diastase and degrade the starch or starch-products to fermentable sugars which can then be attacked by the yeast. It would appear, however, that there exists an action closely analogous to symbiosis between an unorganised and an organised ferment, and i t may be doubted whether the fermentations in which moulds and yeasts are concerned are really instances of true symbiosis, since the former can be replaced by an enzyme with the production of the same result.

ISSN:0368-1645    

DOI:10.1039/CT9017901085

出版商:RSC    

年代:1901

数据来源: RSC

摘要:

1090 HEWITT AND TERVET: ACTION OF BROMINE ON THE CXV1.-Action of Byornine on the mree Tolueneazo- phenols. By J. T. HEWITT and JOHN N. TERVET. THE action of substituting agents on oxyazo-compounds has been studied somewhat extensively by one of the authors of this communi- cation and his co-workers. It has been generally found that towards diliite nitric acid and bromine (in presence of sodium acetate) these sub- stances behave as true hydroxyl derivatives of azo-substances and not as the tautomeric quinonehydrazones. Whilst, however, the behaviour towards warm dilute nitric acid has been examined, not only in the case of benzeneazophenol itself (Trans., 1900, 77, 223), but also fur three tolueneazophenols (Trans., 1901, 7Q, 155) and beuzeneazosalicylic acid (Trans., 1901, 79, 49), no other p-hydroxynzo-compound has been studied with regard to its action on bromine.* It seemed, therefore, of some interest to examine other p-hydroxyazo-compounds, and for this purpose, the three tolueneazophenols were chosen, since their nitration had already been studied with the result that m-tolueneazo- phenol had been found to nitrate far less smoothly than its two isomerides, and, moreover, when m-tolueneazo-o-nitrophenol had been obtained, no means were devised of obtaining its acetyl and benzoyl derivatives, although ethyl might easily be introduced in place of hydro- gen.We found, however, that m-tolueneazodibromophenol not only furnished an ethyl ether but also was acetylated and benzoylated quite normally. o- Tolueneccxodibromopheno 1.Ten grams of o-tolueneazophenol and 20 grams of fused sodium acetate were made into a paste with glacial acetic acid. The mixture was cooled to 10' and 16 grams of bromine, diluted with 40 grams of glacial acetic acid, were slowly added. The dibromo-derivative separated in a crystalline condition, and after a further recrystallisation from boiling glacial acetic acid, i t formed yellow needles melting at 121' (corr.). 0.1530 gave 0.2351 CO, and 0.0391 H20, CI,H,,ON,Br, requires C = 42.16 ; H = 2-72 per cent. The substance is very soluble in acetone; fairly so in aniline, benz- ene, nitrobenzene, ethyl acetate, or ethyl ether ; sparingly so in carbon disulphide and chloroform, and nearly insoluble in light petroleum. C = 41.90 ; H = 2.84. * Benzeneazo-p-cresol (Hewitt and Phillips, Trans., 1901, 79, 160) belongs of course to the ortho-series.'THREE TOLUENEAZOPHENOLS.1091 The two bromine atoms enter the phenol nucleus, since on reduction with tin and hydrochloric acid, o-toluidine is obtained. The presence of the latter was rendered certain by making the reduction product alka- line, blowing steam through the liquid, and shaking the distillate with sodium hydroxide and benzoyl chloride. The benzoyl derivative which separated melted at 139' (uncorr.) after recrystallisation from benzene. Ethyl i%ther.-A solution of O-Z.grain of sodium in 10 C.C. of absolute alcohol was heated with 3 grams of the dibromoazophenol and 1.2 grams of ethyl bromide for 4 hours at 140'. The product was isolated in the usual manner and.recrystallised from spirit ; i t melted at 95'.0.0719 gave 0.0681 AgEr. C15H140N2Br2 requires Br = 40.15 per cent. The substance, which forms orange plates, is very soluble in benzene, carbon disulphide, ether, or ethyl acetate; fairly so in chloroform or light petroleum, and sparingly so in cold alcohol o r acetic acid. Acetyl Derivative.-Prepared by heating with a n equal weight of fused sodium acetate and five times the weight of acetic anhydride. Acetylation is complete after one hour at 100'. When recrystallised from glacial acetic acid, the substance forms orange needles melting at 153'. Br= 40.30. 0.0992 gave 0.0896 AgBr. C,,H,,O,N,Br, requires Br = 38.79 per cent. It is very soluble in carbon disulphide or chloroform, fairly so in aniline, nitrobenzene, acetone, ethyl acetate, or ether, sparingly so in benzene, and nearly insoluble in light petroleum, cold alcohol, or cold acetic acid.Benzoyl Derivative.-Obtained by boiling with three times it's weight of benzoyl chloride for 2h hours in a reflux apparatus. By pouring into excess of cold spirit, the Substance is obtained crystalline, and when once recrystallised from boiling spirit, in which i t is very spar- ingly soluble, small, orange prisms, melting at 168*5O, are obtained. It is fairly soluble in benzene, aniline, nitrobenzene, carbon disulphide, or chloroform. Br = 38.43. 0.1754 gave 0.1399 AgEr. Br = 33-94. C,,H,,O,N,Br, requires Br = 33.73 per cent, m- To Zwneaxodi6romopheno 1. In the preparation of this substance, considerable care is necessary. If m-tolueneazophenol is merely ground u p with fused sodium acetate and acetic acid and then brominated, the mixture becomes warm, con- siderable destruction of the azo-compound takes place, and bromine1092 ACTION OF BROMINE ON THE THREE TOLUENEAZOPHEMOLS.derivatives of phenol are formed in considerable quantity. The desired dibromo-derivative may, however, be obtained in nearly quantitative yield, by dissolving 5 grams of m-tolueneazophenol in 150 C.C. of glacial acetic acid to which 10 grams of fused sodium acetate have been added. The solution is then carefully cooled to 0' and 8 grams of bromine diluted with 25 grams of glacial acetic acid added drop by drop, the mixture being vigorously stirred, since the bromination product crys- tnllises out nearly completely during the process.Collected and recrystallised from glacial acetic acid, the product is obtained in yellow needles melting a t 129'. 0.1417 gave 0.1442 AgBr. Br = 43.00. C,,H,,ON,Br, requires Br = 43.1 9 per cent. The solubilities resemble those of the ortho-compound, but are some- what greater. The constitution of the substance was determined by reduction ; the product, after being rendered alkaline, was distilled with steam, and the m-toluidine in the distillate detected by benzoyl- ation. The benzoyl derivative was free from halogen and melted a t 119O (121-122' corr.). The ethyl ether, prepared in the usual manner and recrystnllised from spirit, forms yellow leaflets melting a t 85'. The solubilities of the substance resemble those of the ortho-isomeride.The acetyl derivative, when recrystallised from glacial acetic acid, forms orange needles of considerable brilliancy and melts a t 118'. 0.1650 gave 10.3 C.C. moist nitrogen at 23' and 760 mm. N= 7.04. C,,H,,O,N,Br, requires N = 6.81 per cent. It is very soluble in ethyl acetate, benzene, carbon disulphide, or chloroform; fairly so in ether, and nearly insoluble in cold acetic acid. The benzoyl derivative separates from hot spirit, in which it is very sparingly soluble, as very small, pale yellow needles melting at 141'. N = 6.17. 0.1866 gave 10.1 C.C. moist nitrogen at 22' and 752 mm. C20H1,0,N,Br, requires N = 5 9 0 per cent. The solubilities of the substance generally resemble those of the isomeric or t ho-compound. p-Tolueneaxodibromophenol. This substance was prepared in exactly the same manner as the corresponding derivative of o-tolueneazophenol.When recrgstallised from glacial acetic acid, i t forms dark yellow, shining needles melting at 137'.DIVERS AND HAGA : NITRILOSULPHATES. 1093 0.1744 gave 11.7 C.C. moist nitrogen a t 16' and 748 mm. N = 7-67. C,,Hlo02N2Br, requires N = 7-58 per cent. The solubility of the substance in the usual organic solvents is somewhat greater than that of the corresponding o-tolueneazodibromo- phenol. Complete reduction of the compound gave p-toluidine as one of the products. After the reduction mixture had been rendered alkaline, steam carried over a volatile base which had a melting point of 45", and gave the usual tests €or ptoluidine. The ethyl etheg- separates from spirit in shining, brownish-yellow needles melting at 954 0.0984 gave 0.0927 AgBr. Br = 40.09. C,,H,,0N2Br, requires N = 40.15. The substance dissolves readily or fairly easily in most organic sol- vents, but like its isomerides is sparingly soluble in cold alcohol or acetic acid. The acetyl derivative crptallises from acetic acid in orange needles melting at 148O. 0.1020 gave 0.0942 AgBr. Br = 39.31. The solubilities of the substance resemble those of the ortho-com- The 6emoyZ derivative separates from boiling spirit, in which i t 0.0996 gave 0.0790 AgBr. Br = 33.75. C,,H1202N,Br, requires Br = 38.79. pound. dissolves only sparingly, as orange-yellow prisms melting a t 114'. C,oHl,02N2Br2 requires Br = 33.73. Again, the solubilities were found to agree closely mith those of the isomeric ortho-compound. EAST LONDON TECHNICAL COLLEGE.

ISSN:0368-1645    

DOI:10.1039/CT9017901090

出版商:RSC    

年代:1901

数据来源: RSC

摘要:

DIVERS AND HAGA : NITRILOSULPHATES. 1093 By EDWARD DIVERS and TAMEMASA HAGA. NITRILOSULPHATES were discovered in 1845 by Fremy, who named them sulphammonates. Their sulphonic constitution was made evident by Claus and Koch in 1869, and their nitrilic constitution by Berglund in 1875, when they received the name of nitrilosulphonates. Finally, Raschig rendered the constitution of these salts still more VOL. LXXIX. 4 E1094 DIVERS AND HAGA : NITRILOSULPHATES. certain in 1587. These chemists, it should be mentioned, added nothing to the experimental facts concerning the nitrilosulphates which Fremy had made known, but Claus and Koch determined the nature of the ‘ sulphazidstes,’ salts derived from Fremy’s ‘ neutral sulphazotates ’ by hydrolysis ; Raschig proved the constitution of the last-named salts, which by sulphonation become the sulphammonates, and Berglund established the constitution of the sulphamidates ’ into which the sulphammonates are transformed by hydrolysis, all the experimental inter-connections of these salts, here relied on, having been ascertained by Fremy himself.The recognition of the constitution of the nitrilosulphates by Fremy was a moral impossibility, for their dis- covery had come, so to say, much before its time. Name.-The reason for the substitution of the name nitrilosulphates for that of nitrilosulphonates, chosen for these substances by Berglund, has been stated on a former occasion (Trans., 1896, 69, 1634). As nitriles they are sulphates-nitrilosulphates therefore. Suitable alternative names are nminetrisulphonates and trisulphamates.Pyeparatiolz.-Ammonium nitrilosulphate, 4NH,,3S03, cannot be obtained by the union of ammonia with sulphur trioxide, for that results in the production of the imidosulphates, which are not resolvable by heat into nitrilosulphate and ammonia, since the less ammoniated &normal salt, instead of breaking tip in this way, boils freely at about 355’ under reduced pressure, with very little decomposition and no production of nitrilosulphate (Trans., 1892,61,947). Nitrilosulphates are only t o be prepared by sulphonation of hydroximidosulphates. Fremy made known two mays i u which this can be accomplished, of which, however, only one admits of general application. This is to treat the hydroximidosulphate with sulphur dioxide in presence of a base, a process which resolves itself in practice into treating the corresponding nitrite in this way, since the hydroximidosulphate has itself to be prepared by a similar sulphonation of the nitrite.The other way of preparing nitrilosulphstes by sulphonation is to add a nitrite to an excess of solution of a pyrosulphite, when in the case of the potassium salt, the nearly insoluble nitrilosulphate soon separates. Other nitrilosulphates, being more soluble, can hardly be obtained directly in this way, but, as Premy has shown, a solution of the am- monium salt thus prepared, very impure though i t will be, can be made to yield potassium nitrilosulphate by double decomposition. Antmonium Salt. Nothing has been done concerning this interesting salt, K(S03NH,),,2H,0, since Fremy described it, but as its existence has been ignored since the time of the publication of its discovery untilDIVERS AND HAGA : NITRILOSULPHATES. 1095 now, we hold i t important to again introduce some account of it derived from Fremy’s memoir (Ann.Chirn. Plqs., 1845, [iii], 15, 408) into chemical literature. In presence of a large excess of ammonia, a concentrated solution of ammonium nitrite is submitted t o the action of a current of sulphur dioxide until abundant precipitation of crystals has occurred in the solution kept sufficiently cool. The washed and dried salt gave Fremy the following numbers on analysis, indicating the presence of one niolecular proportion of water of crystallisation : N4H14S3010 ’ 29.45 17.18 4.29 Found .. . . . . . . . 30-2 15.7 4.5 Sulphur. Nitrogen. Hydrogen. Since the potassium nitrilosulphate contains 2 mols. of water, it is probable that the ammonium salt contains the same, and that when Fremy determined the sulphur the salt had, like the sodium salt, lost some of its water during its stay in the desiccator. W e write, there- fore, the formula of the salt, N(SO,NH,),,ZH,O. Ammonium nitrilosulphate separates in minute crystals which have only a slight taste, and are somewhat sparingly soluble in water, but so much more so than the potassium salt t h a t Fremy suggested that its solution might be used as a qualitative reagent for potassium salts. It is not volatilised by heat, but is decomposed into sulphate. I t is a very unstable salt, being liable in the solid state to decompose (hydro- lyse) suddenly with a hissing sound, charring paper in contact with it. We have already announced (Trans., 1900, 7’7, 689) our success in converting ammonium nitrite into hydroximidosulphate by a method of sulphonation which, carried farther, gave Fremy the nitrilosulphate.Ammonium nitrilosulphate has the interest attached to it of being one more compound of ammonia with sulphur trioxide to be added to those recognised. There are six such compcjunds : (1) NH32S0, = HN(SO3H) 2 (3) 4NH33S0, = N(SO,NH,), (4) 3NH32S03 = HN(SO3NH4)2 (3) NH, SO, = H,N SO,H ( 5 ) 4NH32S03 = (NH4)N(S0,NH4)2 (6) ZNH, SO, = H,N SO,NH, Of these, the second is amidosulphuric acid, and the sixth its ammon - ium salt (Trans., 1896, 69, 1634); the first is imidosulphuric acid, known only in unstable solution (Trans., 1802, 61, 945) ; the fourth is its $-normal ammonium salt (parasulphatammon of Rose) ; and the fifth, polymeric wit8h the sixth, is its normal ammonium salt (sul- phatalnmon of Rose ; Trans., 1892, 61, 946); and the third is ammon- ium nitrilosulphate here described.These six compounds can all be1096 DIVERS AND HAGA : NITRILOSULPHATBS. derived the one from the other, backwards as well as forwards, except the nitrilosulphate, which cannot be reformed from the others although itself the most convenient source of them. Nitrilosulphuric acid would be the seventh of these compounds, heading the column as NH3,3S0,, if it couldexist in the free state. Potussizcm Xu&. The potassium salt, N(S03K),,2H,0, is familiar to those who have occupied themselves with the study of Fremy’s sulphazotised salts, being one of the most insoluble of potassium salts, even more so than the percblorste (Fremy).It forms slender needles of pearly lustre, which in crystallising fill its mother liquor. The work of later investigators has added nothing to the account of it given by Fremy, except that the crystals are rhombic (Raschig and Fock).” His analyses gave results which agree well with those calculated for the true composition of the salt, though not with his own formula for it. By preference, he pre- pared it by passing sulphur dioxide into a solution, not too concen- trated, of the nitrite and the hydroxide. With the neglect of details characteristic of his celebrated memoir, he fails, however, to mention the essential potassium hydroxide.Probably, on account of this, later workers have only made use of‘ his other process, which consists in mixing solutions of the nitrite and pyrosulphite. Sodium Salt, N(S03Na)3,5H,0. A strong solution of sodium pyrosulphite poured upon solid sodium nitrite furnished Raschig (Annulen, 1887, 241,180, 229) with a useful solution of the nitrilosulpbate, although it contained much hydr- oximidosulphate, sulphite, and unchanged nitrite ; sodium hydroxide he represented also to be present, but that could not have been the case (Trans., 1900, ’77, 675). We have found that instead of 3 mols. of pyro- sulphite, which was the quantity used by Raschig, to 2 mols. of nitrite, at least 4 mols. must be taken if most of the hydroximidosulphate is to be su1phonated.l- By preparing from the carbonate (using this in hydrated crystals, along with only half its weight of water, and satur- ating with sulphur dioxide) a fresh and pure solution of pyrosulphite as concentrated as possible, pouring this solution upon the nitrite dis- * Misled by the faulty translation in the Annulen (1845, 56, 342) of Fremy’s papey, CIaus and Koch supposed that he had said that red fumes were evolved when the salt is heated.Fremy’s statement is that the salt does not evolve red fumes, which is correct. j. Claus and Koch found it best to take still more pyrosulphite when working with the potassium salts (Annulen, 1869, 152, 336), and they were right, for in the case of that insoluble nitrilosulphate, great excess of sulphite did not matter ; here it does.l-)TVERS AND HAGA : NITRILOSULPHATES.1097 solved in its own weight of mater, 1 mol. of nitrite to every 2 mols. of carbonate taken, and shaking the flask in cold water for a short time t o moderate the rise of temperature, a solution is obtained which will in a n hour or two deposit a small quantity of sparkling crystals of the nitrilosulphate, and give a further amount when i t is evaporated over sulphuric acid. The eqiirttion NaNO, + 2Na2S20, = N(S03Na)3 + Na,SO, represents the change, but this would take many days t o become complete, long before which time the nitrilosulphate would have all decomposed, I n the mixed solubion only a few hours old, some hydroximidosulphate, as well as nitrite, is still present.The only satisfactory method of preparing sodium nitrilosulphate is a slightly modified form of that employed by us to get the imido- sulphate (Trans., 1892, 61, 954). I n that process, which is, after all, only a development of Frerny’s method of preparing the ammonium salt, the nitrilosulphate is prepared and at once allowed to hydrolyse into imidosulphate, whereas in the present case its hydrolysis is t o he prevented, There, a moderately concentrated solution met the end in view, whilst here the greatest possible concentration is wanted, because evaporation of the solution afterwards, although sometimes successful, is a very uncertain operation, in consequence of the short existence which can be assured to the nitrilosulphate. h solution therefore i s prepared of 2 mols.of nitrite to 3 mols. of carbonate, so concen- trated that the water is scarcely more than twice the weight of the anhydrous carbonate (for example, 10 grams of nitrite, 8.5 grams of hot water, and 62.2 grams of carbonate crystals). Sulphur dioxide is passed rapidly into the solution in a flask continuously shaken. When, after a time, the solution grows hot, the flask is immersed in cold water, and when i t thicken$, through temporary separation of acid carbonate, vigorous shaking of the flask is to be maintained without intermission. A s the quantity of the acid carbonate suspended in the warm solution (50-60’) lessens, the rate of current of the sulphur dioxide should be reduced and the action of the solution upon litmus paper closely watched. At the moment the solution reddens the litmus, the entrance of more sulphur dioxide must be stopped, for should acidity to lacmoid paper also be reached, through the addition of much more sulphur dioxide, the nitrilosulphate will a t once hydrolyse into the imidosulphate.During the final slow sulphonatioa, the solution will generally grow cold enough t o begin t o deposit small crystals of the nitrilosulphate, recognisable by their brilliant lustre ; these will increase largely in quantity at the temperature of the air. Without waiting too long, it is safer to add two or three drops of concentrated solution of sodium hydroxide, sufficient to render the solution faintly alkaline to litmus. It is possible t o get more of the salt by evaporating the mother liquor over sulphuric acid.1098 DIVERS AND HAGA : NITRILOSULPHATES.That the reaction proceeds sharply in accordance with the following equation, is known from the quantity of imidosulphate which such a solution can be made to furnish : 2NaN0, + 3Naf,C0, + SSO, = ~N(SO,NR)~ + Na,S,O, + 3C0,. I n consequence, however, of the great solubility of this nitrilosulphate, the crystals obtained amount to barely more than one-fifth of the total quantity; still, even that is 120 per cent. of the weight of nitrite taken. The crystals hold 21.8 per cent. of water, or 5H,O. Of this quantity, it has twice been possible to remove 15.5 per cent. by expos- ing the salt in a vacuum over sulphuric acid, after which the salt has hydrolysed, and thereby fixed the rest of the water.The production of the unused pyrosulphite, shown in the above equation, is necessary for the safe and prompt sulphonation of all the hydroximidosulphate. Sodium nitrilosulphate crystallises in short, thick prisms which melt when heated and decompose in their water of crystallisation into sulphates. The crystals cannot be long preserved under any circum- stances, soon suffering decomposition and becoming op'iqiie and acid, even in their own mother liquor after it has been made alkaline. That is, the sodium salt is more unstable than the potassium salt. It is neutral to litmus, and must be soluble in about its own weight of water, t o judge from the amount of it left in the mother liquor in its preparation, although here, no doubt, the pyrosulphite also in solution will affect its degree of solubility.For analysis, it was drained on the tile after washing with n little strong ammonia-water, in which it is less soluble than in water. Partial water determinations have already been referred to. Sulphnr. Sodium. Nitrogen. N(S03Nit),,5H20 ......... 23.24 16-71 3.39 - Found ..................... 23-05 16-54 ,, ..................... 22-96 - 3.64 ,, ..................... 23.25 16.68 ,, ..................... 23.17 - 3-45 - 16-55 - - ,, ..................... Double Salts. Potassium Sodium Nitriloszclphate, N(SO,),K,Na. -Raschig obtained this salt by adding a solution of potassium chloride gradually to a crude solution of sodium nitrilosulphate (p. 1096). We have obtained the same salt, which is like the sodium salt in appearance and like the potassium salt in being nearly insoluble. According to Raschig, i t is anhydrous, and occurs either as a sparkling sand or in hard crystals the size of pinheads and of adamantine lustre.AMMONIUM BED OTHER IMIDOSULPHITES. 1099 Bc6rium Salts.-By dissolving the sodium salt in a strong solution of barium chloride rendered faintly alkaline with ammonia, a flocculent precipitate is obtained which becomes dense and crystalline on stand- ing. It probably contains sodium, but we have not analysed it. Fremy obtained barium ammonium and barium potassium salts, which he could only analyse imperfectly because of their instability. They resembled the barium sodium salt, and from the results of his analyses appear to have been two-thirds barium and one-third ammonium or potassium salt, with water of crystallisation. Lead Salts.- According to Fremy, very unstable lead salts containing potassium or ammonium are obtainable. It is sparingly soluble in water and very unstable.

ISSN:0368-1645    

DOI:10.1039/CT9017901093

出版商:RSC    

年代:1901

数据来源: RSC