ORGANIC CHEMISTRY-ALIPHATIC DIVISION,ALTHOUGH it cannot be said that, during the past year, any verystriking or exceptional discovery has been made in the chemistry ofthe aliphatic compoiinds, yet a vast amount of important work hasbeen done in this department, and the rosclts obtained certainlymark a steady advance in nearly every direction.From the nature o€ the subject it will be readily understood that;a report dealing with experiments which cover so wide an area mustnecessarily take the form of a series of separate, and oftBen isolated,accounts; any attempt at a continuous method of treatment is, ofcourse, out of the question.The subjects have been considered as far as possible in the usualorder of the various organic families or types, but a strict classifica-tion under these heads is, in many instances, undesirable.Hydrocarbons and Combustion.A new octane, namely, hexamethylethane, (CH,),C*C(CH,),, has beenobtained by Henry1 as a by-product in the preparation of pinacolylalcohol by Grignard's reaction, and also from bromopentamethyl-ethane by the action of magnesium methyl bromide (see page 82).It is a crystalline solid which melts at 103O.Clarke and Shreve found that, during the reduction of methyliso-butylpinacone with hydrogen iodide a small quantity of a hydro-carbon is formed which proves to be a new dodecane, namely, dimethyldi-isobutylethane, (CH,),CH*CH,~CH(CH,)*CH(CH,)~CH;CH(CH,),.It has been shown by Lebeau3 that hydrocarbons of the aliphaticseries may be obtained from their halogen derivatives by means ofthe metalammoniums ; methane, for example, is produced from methylchloride and sodammonium.Chablay has extended these observa-tions, and shows that ethylene may similarly be obtained fromethylene dichloride ; propylene, $-butylene, isobutylene, andtrimethylene result in the same way from their respective bromides.The dichlorides of methylene, ethylidene, and propylidene, on the otherhand, yield the paraffins, methane, ethane, and propane respectively. TheCornpt. rzizd., 1906, 142, 1075.3 Compt. I W L ~ . , 1005, 140, 1042." Anzer. Chenz. J., 1906, 35, 513.Loc. cit., 1906, 142, 937 2 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.same author finds that unsaturated primary alcohols of the aliphaticseries react with metalammoniums to give corresponding unsaturatedhydrocarbons, propylene, for example, being obtained, in quantitativeyield, from ally1 alcohol.A method of preparing olefines is suggested by Mailhe2 whichconsists in decomposing the monohalogen-substituted ptraffins by meansof reduced nickel, cobalt, or copper.The products, halogen-acid andolefine, are afterwards separated by means of caustic alkali. Drychlorides of bivalent metals behave similarly as catalytic agents inbringing about this decomposition ; chlorides of univalent metalsappear to be inactive. From these results the author assumes the forma-tion of intermediate compounds, C,H,,:( MCI)CI, in the former case.The simple hexatriene, CH,:CH*CH:CH*CH:CH,, was obtained byvan Romburgh an? Dxssen (1905) by the action of heat on the di-formslte of s-divinylglycol. Smedley 3 has lately carried out a seriesof investigations with the object of preparing hexstrienes fromaa-dichloropropylene and its homologues ; it is found that when thelatter compound is heated with metallic sodium in petroleum at about80' a small quantity of diallyl is produced, whereas it had been statedby previous observers that these two substances do not interact.Therois produced also a small quantity of a liquid which boils at 80' whichis probably identical with the hexatriene above mentioned.It was shown by Walker in 1893 that sodium o-ethylcamphorate, on electrolysis, yields the ester of an unsaturated acid,subsequently proved to b? an ap-compound (isolauronolic acid).Campboric acid being a derivative of glutaric acid, it follows thatduring electrolysis of the abwe-named salt a methyl group movesfrom one carbon atom and becomes attached to an adjacent one.Potassium glutarate also on electrolysis yields, not trimethylene, butpropylene, the result indicating that here again the migration of anatom of hydrogen must have occur.red.4 It became, therefore, amatter of interest to ascertain the behaviour of P/3-.dimethylglutaricacid since, in this case, such a transference of the hydrogen atom isimpossible, and if an open chain hydrocarbon is produced it must resultfrom the transference of a hydrocarbon group as a whole.Walkerand Wood find that the result in this case is unsymmetrical methyl-et hy let hylene :CH2* C0,Na 7%- FH,*CH,CH, *Y.CH, -+ CH,*Y*CH, -+ E*CH, .CH,*CO,Na CH2- CH2Compt.rend., 1906, 143, 123. Chem. Zeit., 1906, 30, 37.:* Proc., 1906, 22, 158.4 Vanzetti, Atli. R. Accnd. Lineti, 1904 [v], 13, ii, 112.Trnns., 1906, 89, 598ORGANIC CHEMISTRP-ALIPHATIC DIVISION. 73There is therefore a fundamental rearrangement of the carbonnucleus, a four-carbon chain resulting from one of three carbon atoms.H. Jackson and D. Northall-Laurie have studied the change whichtakes place when acetylene is subjected to electrical discharges of highfrequency. It is found that a semi-solid brown substance is producedwhich sets to a hard and very insoluble solid on exposure to air. Ifcare is taken to avoid secondary reactions the composition of theproduct is the same as that of acetylene.This substance, which isapparently a polymeride of acetylene, readily absorbs oxygen up toabout 8 per cent. When heated out of contact with air it yields avolatile oil together with a sinall quantity of methane and hydrogen.The same authors2 have also studied the behaviour of methyl alcoholand of acetaldehyde when their vapours are subjected to high-frequency discharges. They find that, with discharges of very shortduration, methyl alcohol yields carbon monoxide and hydrogen, whilstacetaldehyde gives methane and carbon monoxide together with someacetylene and water. Both these changes are reversible, the lattermore readily than the former. The authors have continued theexperiments, which were initiated by one of them some time ago, on anumber of saturated and unsaturated compounds, and they concludethat in the case of paraffiin derivatives :he general tendency is forunsaturated compounds to give polymeric varieties under the influenceof the discharges, whilst saturated compounds under similar con-ditions yield substances of simpler structure.Experiments on the direct union of carbon and hydrogen have hithertobeen carried out either at temperatures of 1100-1300" or at thetemperature of the electric arc between carbon electrodes in hydrogen.Pring and Hutton 3 have recently made a series of observations on thecourse of the reaction at temperatures from 10003 up to about 2800'.Their results indicate that the proportion of methane formed is muchsmaller than was t o be expected from the results of some formerobservers and that the yield is still lower if the carbon rods have beenpreviously purified by heating to a high temperature in chlorine.Theformation of acetylene is just perceptible at 1700O asd becomes pro-gressively greater with increase of temperature up to about 2500'.Bone and Drugman4 have made extensive experiments on thepropagation of a flame, under ordinary conditions, through mixtures oftypical hydrocarbons with amounts of oxygen insufficient for com-plete combustion; from their results they infer that there is noessential difference between the mechanism of combustion above andbelow the ignition point, both phenomena involving the initial forma-tion of hydroxylated molecules.These conclusions are based chieflyProc., 1906, 22, 155.Tram., 1906, 89, 1591,LOG. cit., 156.LOC. cit., 66074 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,on the fact that there is a remarkable contrast between thebehaviour of olefines and paraffins when exploded with a proportion ofoxygen represented by the relation C,H,+x/20,, and also on thephenomena associated with the inflammation of a mixture of an olefinewith much less oxygen than is represented in this expression. TheBame authors and Andrew have further investigated the behaviourof mixtures of oxygen with ethane and with ethylene, in the propor-tions C,H,+O, and 3C2H,+20,, in such a manner that some dis-crimination could be made between the various products of combustionaccording as they arise at an earlier or later stage in the flame.Theresults indicate that there is probably no essential difference between‘‘ detonation ” and ‘‘ inflammation ” so far as the result of the initialencounters between individual molecules of hydrocarbon and oxygen isconcerned.The same authors2 have made experiments with the object ofascertaining whether the presence of water vapour has an influence onthe combustion of a hydrocarbon which is at all comparable with thatexerted in the cases of carbon monoxide and of hydrogen. Ethyleneand acetylene were selected for experiment, since it had been previouslyshown that no steam is produced in the initial stages of their slowcombustion. The results were compared when the dried and the un-dried hydrocarbons were heated, under similar conditions, with oxygen,and the authors conclude that the rigid exclusion of moisture, bymeans of the best known methods of desiccation, has little if anyinfluence on the rate of oxidation of a hydrocarbon.Action of Ozone.Drugman3 has made a further study on the oxidation of hydro-carbons by ozone a t low temperatures, and his results show that thereis a radical difference between the behaviour of saturated and un-saturated hydrocarbons. I n the case of saturated hydrocarbons,gradual hydroxylation of one carbon atom takes place ; the alcohol isfirst formed and is then quickly oxidised to the relatively stablealdehyde and more slowly to the acid.Unsaturated hydrocarbons givefirst an ozonide or peroxide, which readily decomposes, yieldingproducts containing a less number of carbon atoms.Ethylene reactsso violently with ozone, even a t very low temperatures, that the initialproduct could not be isolated; in the moist state, the products of thereaction were formaldehyde, formic acid, and hydrogen dioxide. Thechanges are probably t o be represented as follows :Trans., 1906, 89, 1614. L‘ LOC. cit., 652.Loc. cit., 939ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 75C2H,03 + H,O = 2H*CHO + H202.An extensive series of investigations has been carried out duringthe last few years by Harries and his colleagues on the bchaviour ofozone towards various organic compounds, and a valuable summary ofthe work has recently been published by the auth0r.l I n conductingthese experiments the substance t o be examined is usually dissolved indry chloroform and a current of ozoniaed oxygen, mixed with carbondioxide, is passed into the solution at a low temperature.Under theseconditions the danger of explosion is lessened and volatile products areremoved in the current of gases. Amongst the many interestingresults which have been obtained, the behaviour of unsaturated com-pounds is perhaps the most important. Unsaturated hydrocarbons oralcohols which contain an ethylene linking combine with one moleculeof ozone to give ozonides, which are usualiy thick oils or syrups andare often explosive. They behave like peroxides in their power ofliberating iodine from potassium iodide and in bleaching potassiumpermanganate or indigo.By the action of water they are decomposedwith production of aldehydes, ketones, peroxides of these, or hydrogendioxide, disruption of the carbon chain occurring a t the position of theoriginal double linking. The author represents these ozonides as con-taining quadrivalent oxygen, although it is perhaps doubtful whetherthere is here any advantage in making this assumption. On this viewthe typical decomposition may be represented asone of tlie -resulting aldehydes or ketones appearing as a peroxidewhich may yield hydrogen dioxide by action of water. Unsaturatedcompounds containing a carbonyl group, such as ketones, aldehydes, ormonobasic acids, when acted on by ozone in the way above mentioned,are found to combine with four atoms of oxygen instead of three ; inthe resulting '' ozonide-peroxides " the additional atom of oxygen isattached to the carbonyl group.On decomposition by water, the latteroxygen appearj as hydrogen dioxide, the ozonide grouping splitting upin the manner above indicated. As examples of these typical decomposi-tions one may refer in the first case to ozonides of the typewhich by the action OF water give the ketone peroxide andAxlzalen, 1905, 343, 31176 ANNUAL REPOnTS ON THE PROGRESS OF CHERiIS'ITtY.the aldehyde R*CHO, and secondly to the ozonide of mesityl oxide,lwhich yields acetone peroxide, methylglpoxnl, and hydrogen dioxide.The latter decomposition should, in accordance with the author's laterview, be represented as follows :0 C( CH,),OQ&~H-C(CH~):O:O +H20 = (CH,),C<Z + CHO*CO*CH, + H,O,.These typical actions of ozonides not only afford simple methods ofobtaining various aldehydes, ketones, &c., which have hitherto beenunknown or difficult to prepare, but the results may also be applied, inmany cases, to the determination of constitution.I n the light of theevidence obtained from these researches, the author discusses, forexample, the constitution of dialiyl, crotonic and isocrotonic acids,oleic and elaidic acids, benzene, naphthalene, and many othercompounds.The behaviour of Para-caoutchouc towards ozone has already beenreferred to in the last Report (p. 80) ; the diozonide, C,,H,,O,, whichis formed is decomposed by water with prodnction of *lsvulinaldehydeand its peroxide and lawulic acid.Similar experiments have sincebeen made by Harries2 with the hydrocarbon C,,,H,, from guttapercha; the results obtained are quite analogous, except that theozonide gives, on decomposition, a greater proportion of laevulic acid andless aldehyde. The results indicate that the parent hydrocarbons arethe same but that the ozonides are different. This difference, theauthor considers, may be due to stereoisomerism. Representing thehydrocarbon as 1 : 5-dimethylcyclooctadiene the diozonides will havethe constitutionV-?(CH,)*CH,*CH,*$JH-O"0-CH- CH2--CH2--C( CH,)-O ' >o,in which the ozonide or methyl groups can be situated in the cis- ortrans-position with respect to the plane of the ring. I n order t oaccount for the different bebaviour on decomposition, the splitting olone pair of oxygen double linkings in each of the two ozonide group-ings may be supposed to occur either in the adjacent or in the oppositepairs.It has already been shown by the author that oleic acid in chloroformsolution, whenacted on by ozone, combines with four atoms of oxygen,behaving therefore in the normal manner of a n unsaturated compoundcontaining the carbonyl group.This product has been further studiedby Harries and Thieme.3 When washed with water and sodium hydro-gen carbonate it yields the normal ozonide and t'he aqueous solutionCompare Ann. Report, 1905, 74. Ber., 1905, 38, 3985,LOG. cit., 1906, 39, 2844ORGANIC CHEMISTRY-ALIPHATIC DIVISION.77shows strongly marked reactions of hydrogen dioxide.duct is therefore oleic acid ozonide peroxide,The initial pro-CH3*[CH,]7*CH*CH*[CH2]7*C0,H.\/0 3The normal ozonide may also be obtained by ozonising oleic acid in aceticacid solution, diluting with water, and neutralising with sodium hydro-gen carbonate. Both these products on decomposition with wateryield azelaic acid or its semialdehyde and nonylic acid or aldehyde;hydrogen dioxide is produced in both cases, but in much larger propor-tion from the ozonide peroxide.Molinari and Soncini obtain the normal ozonide by action of ozoneon oleic acid itself, without use of a solvent, and also when an aceticacid solution is employed. Under the conditions of their experiments,therefore, only three atoms of oxygen would appear to be taken up byone molecule of the acid.A question of priority also a.rises here, sincethe last-named authors claim to have commenced the study of theaction of ozone on various oils in 1903. Weyl, however,2 points outthat in 1898 he applied for a patent for obtaining disinfecting substanceswhich were prepared by the action of ozone on acids of the oleic series.A study of the decomposition products of oleic acid ozonide has beenmade by Molinari and Soncini with the object of establishing the con-stitution of oleic acid. They show that by the action of alkalis four acidsare obtained, in addition to a neutral substance which was not identified.These four acids prove to be : (1) azelaic acid, CH,(*[CH,],*CO,H), ; (2)normal nonylic acid, CH,*[CH,],*CO,H; (3) a monobasic acid, C,,H,,O,,CH3*[CH217\C/OH and (*) ft which appears to have the constitutionCH,*[CHJ7/ \CO,H’ ~~ O*SH*[CH,]7*C0,HO*CH-[CH,]7*C0,H* dibasic acid, I 1The formation and decomposition of this normal ozonide leaves nodoubt, in the authors’ opinion, that the double linking in oleic acid isbetween the atoms C, and Clo.An interesting general method of obtaining the dihalogen derivativesof paraffins is afforded by the reaction discovered by Braun,4 whichconsists in the action of phosphorus pentachloride or pentabromide oncyclic imino-compounds.Benzoylpiperidine, for example, when actedon by phosphorus pentachloride, yields aedichloropentane and benzo-nitrile, the latter being easily removed by steam distillation, Braunand Beschke have recently shown that pyrrolidine behaves similarly.1 Ber., 1906, 39, 2735.LOC. eit., 3347. Loc. cit.Ann. Keport, 1904, 71. Ber., 1906, 39, 411978 ANNUdL REPORTS ON THE PROGRESS OF CHEMISTRY.When benzoylpyrrolidine is beated with phosphorus pentachloride, thechanges which take place depend somewhat on the conditions, the pro-ducts being either benzo-6-chlorobutylamide, or dichlorobutane andbenzonitrile : [CH,];N*CO*C,H, -+ [CH,],*N*CCi,*C,H, and[CH,~,*N*CCL,*C,H, = CH2Cl[ CH,],*NH*CO *C,H, orCH,Cl[CH,],*Cl+ NC*C,H,By the same type of reaction Braun and Schmitz have obtained di-chloro- and dibromo- octanes from coniine. Benzoylconiine, when heatedwith phosphorus pentachloride, gives in the first instance the ‘ amide-chloride,’ C,H,,*N(Cl,)C,H,, and this, when quickly distilled, breaks upinto dichloro-octane and benzonitrile, as in the previous example,Nef, in 1897, came to the conclusion that certain halogen-substitutionproducts of the hydrocarbon C2H2 must be regarded, not as acetylenecompounds, but as derivatives of acetylidene, H2C: C, containing bi-valent carbon.At first it appeared probable that compounds of bothtypes might exist, such as the mono- and di-substituted acetylenes,RCiCH, RCiCR,and the isomeric acetylidenes, RHCZC, R2C:C. But thisappears not to be the case, since all the known halogen-substituted hydro-carbons corresponding with these formule, such as Behrend’s di-iodo-acetylene, Sabankeff’s monobromoacetylene, and Wallach‘s monochloro-acetylene, are t o be regarded, according to Nef, as acetylidene deriv-atives, The so-called iodoacetylene of Baeyer is stated to be, in reality,di-iodoacetylidene. The monohalogen-derivatives of alk ylated andarylated acetylenes, however, such as CH,*CiCI and C,H,*CiCX, can beisolated ; they prove to be sweet-smelling and ‘ harmless,’ whereas theacetylidene compounds are highly poisonous, sometimes spontaneouslycombustible, and have a disagreeable odour.Lemoult, in 1903, by the action of alcoholic potash on tribromo-ethylene, obtained a compound which he regarded as dibromoacetylene,but which is probably also an acetylidene compound.It is now shownby Lawrie 2 that the latter substance unites with hydrogen iodide togive an addition compound, C,Br,,HI, which is obtained as a heavyoil.When this product isoxidised by nitric acid it yields dibromo-acetic acid and iodine, and when treated with alcoholic sodium phenoxideit gives unsymmetrical phenyl dibromovinyl ether, Br2C:CH*O*C,H,.That the two bromine atoms are here united to the same carbon atomis shown by the fact that nitric acid converts the compound almostquantitatively into isomeric dinitrophenyl dibromoacetates,CHBr,*CO,*C,H,(NO,),,and these by the action of ammonia yield the isomeric dinitrophenolsand dibromoacetamide.From these and other observations the author concludes that the1 Ber., 1906, 39, 4365. Amer. Chem. J., 1906, 36, 487ORGANIC CHEMISTRY-ALIPHATIC DIVISION.79mono- and di-halogen substituted acetylenes are unknown and that itis extremely improbable that such compounds will be isolated.AZcol~oZs, Aldehydes, and Ketones.Henry * proposes to distinguish tertiary from primary and secondaryalcohols by the actions of acetyl chloride ; this reagent converts primaryand secondary alcohols quantitatively into acetic esters, whilst tertiaryalcohols yield the corresponding chlorides. With fuming hydrochloricacid again, tertiary alcohols, except those of high molecular weight, areat once converted into chlorides even in the cold, whereas primary andsecondary alcohols are not esterified unless the mixture is heated. Theauthor is of opinion that tertiary alcohols are to be regarded asalcohols par exceEZence and that in them the true alcoholic function ismost simply represented, since, in their behaviour, they most nearly re-semble metallic hydroxides. The latter react with ncetyl chloride, forexample, to give a metallic chloride and acetic acid, and the difficulty ofpreparing the sodium derivative of trimethylcarbinol is compared tothe inertness of sodium hydroxide to metallic sodium.According to the French patent (360,180) of Jouas and others, thepreparation of ethyl alcohol from acetylene is effected by passingthe gas into a mercuric salt, which causes the precipitation of mercuryacetylide.On boiling the resulting mixture, acetaldehyde is producedand the mercuric salt regenerated. The aldehyde is afterwards reducedto alcohol by sodium amalgam, or it may be used for the preparationof acetic acid by oxidation.prepare pure methyl or ethyl alcohol by actingon a solution of potassium methyl or ethyl sulphate with rather morethan the calculated quantity of pure sulphuric acid, concentratingthe distillate by fractionation and by means of potash, and finallyremoving the last traces of water with filings of metallic calcium.The alcohols so prepared are quite odourless, and are not colouredwhen heated on a water-bath with an equal volume of sulphuric acid.As examples of some of the recent applications of Grignard'sreaction to the preparation of alcohols, the following may be men-tioned, Reif,4 by acting with magnesium ethyl bromide on croton-aldehyde, obtains the unsaturated alcohol AB-hexene-8-01,and, with magnesium prop91 bromide, in a similar way, As-heptene-Klason and NorlinCHa*CH: C EI*CH(OH)*CH,*CH,,8-01, CaH,*CH(OH)* CgHpBull.Acnd. roy. Bely., 1906, 261.a LOC. cit., 537, and Cbmpt. rend., 1906, 142, 129.:; AT-kiz?. Kena. Min. Geol., 1906, 2, No. 24, 1. Btr,, 1906, 39, 160380 ANNUAL REPORTS ON THE PROGRESS OF CHEMlSTBY'.From ethyl chloroacetate and magnesium ethyl bromide Susskindprepares chloromethyldiethylcarbinol, CH,Cl*C(C,H,),*OH, and Paaland Weidenkaff,2 by the action of magnesium phenyl bromide onethyl glycollate, obtain diphenylethylene glycol,(C,H,),*C(OH) CH,*OH.Fournier ?I states that in preparing alkyl bromides by the action ofhydrogen bromide on primary or secondary saturated alcohols, it isnot necessary, as was supposed, to heat the mixture under pressure.The author prepares a regular current of hydrogen bromide bydropping bromine into toluene in contact with iron wire.The gas ispassed into the heated alcohol at a suitably regulated temperature,the excess of hydrogen bromide is afterwards expelled, and theresulting alkyl bromide distilled off. Operating in that way, a yieldof 70 per cent. is obtained.Wohl and Schweitzer have shown that aliphatic dialdehydes, inthe form of their acetals, may be obtained by the electrolytic method,the changes being quite comparable with those which take place inKolbe's well-known synthesis of hydrocarbons. The double acetal ofsuccinic dialdehyde, for example, results from the electrolysis ofpotassium P-di-ethoxypropionate :Potassium diethoxybutyrate similarly yields the double acetal ofadipic dialdehyde, acraldehyde acetal being also produced.Thedialdehydes themselves are obtained by hydrolysis of the acetals withdilute sulphuric acid. Adipic dialdehyde is in ordinary circum-stances very stable, but when heated with water for five hoiirs at1 1 Oo with continued agitation, it yields cyclopentenealdehyde,CH,-YH,CHO*QQQH-CH,.The latter compound was obtained in 1898 by Baeyer and Liebigwhen attempting the preparation of adipic dialdehyde by the actionof lead peroxide on dihydroxysuberic acid.Haehn5 describes a method of preparing ketones by the action ofcalcium carbide on monobasic fatty acids.The dry acids react in thecold with calcium carbide t o produce acetylene; but a t a highertemperature the ketones are obtained :2R*CO,H = R0CO.R + CO, + H,O.Ber., 1906, 39, 225. Loc. cit., 2062.Ber., 1906, 39, 890. 3 Bull. SOC. chim., 1906, [iii], 35, 621.6 LOC. c i t . , 1702ORGANIC CHEMISTRY-ALl PHATIC DIVISION. 81The water produced then reacts with calcium carbide to produceacetylene and calcium hydroxide or oxide. It might, of course, bethought that the change consists simply in the usual decompositionof the calcium salt, but the author considers that such is notthe case, since the products are not necessarily the same. Calciumisovalerate, for example, on heating yields principally valeraldehyde,whereas isovaleric acid and calcium carbide give principally valerone,with only little valeraldehyde.I n a later communication 1 the author suggests that, in the above-rrientionecl change, the acid anhydride is first produced, and is thencatalytically decomposed by fresh calcium carbide into the ketone andcarbon dioxide.It is shown, for example, that acetic anhydride whenheated with the carbide yields acetone, Ketones are produced in thisreaction of acids with calcium carbide a t a much lower temperaturethan by the dry distillation of calcium salts.With the object of ascertaining whether acetone can behave towardscertain reagents as isopropenyl alcohol, CH,*C(OH):CH,, Taylor hasstudied the action of sodium and of magnesium methyl iodide onacetone. It is shown by the author that the so-called eodium-acetoneis a mixture of caustic soda with R small proportion of isopropyloxide ; this result indicates that acetone does not contain any hydrogendirectly replaceable by sodium under the conditions employed. By theaction of Grignard's reagent, a t the ordinary temperature and up to 1 40°,no methane was liberated.I n these cases therefore acetone shows noindications of the behaviour above suggested.The question is discussed by Rothmund3 whether the compoundswhich acetone forms with alkali sulphites, or bisulphites can existin aqueous solution. It has been shown that in alkaline photo-graphic development by quinol or pyrogallol, a mixture of acetone anda sulphite may replace the alkali; also if a solution of a sulphite,made neutral towards phenolphthalein by addition of an acid, is mixedwith acetone, it becomes alkaline towards that indicator.Theseresults indicate that the change should be represented as (CH,),CO+SO, + H,O = C,H60*HS0, + OH, sulphurous acid being approximatelydibasic towards phenolphthalein, acetone-sulphurous acid monobasic andthe latter being a stronger acid. Electric conductivity and cryoscopicmeasurements favour this view.It has been shown by Couturier and Meunier (1905) that acetonereacts with magnesium amalgam to give a compound which probably-- - -has the constitution Mg< 0*(?(CH3)2, and that this is decomposed by0. C(CHJ2Arch. Pharm., 1906, 244, 234. PTOC., 1906, 22, 173.3 Monntsh., 1905, 26, 3545.VOL. 111. 82 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.water with formation of pinacone hydrate.As a method of preparingpinacone, Holleman 1 modifies this process by acting with magnesiumwire on a solution of mercuric chloride in acetone ; the yield is about35 per cent. of the acetone employed.Henry 2 finds that pinacolin reacts with magnesium methyl bromideand yields pentamethylethanol, CMe3*CMe,*OH, which Butlerofforiginally obtained in 1875 by the action of zinc methide on trimethyl-acetyl chloride. This reaction, and the formation of /3-cyano-yy-dimethylbutan-/3-01, CMe,*CMe(OH).CN, by the action of hydrogencyanide on pinacolin, are brought forward as further proofs of theketonic nature of pinacolin.The same author 3 shows that succinic pinacone,OH*CMe,*CH,*CH2*UMe,*OH,is produced by the action of magnesium methyl bromide on ethyl 1m.u-late, COMe*CH,*CH,*CO,Et.Zelinsky in 1902 obtained a compound,which is doubtless identical with this, by action of magnesium methylbromide on acetonylacetone, COMe*CH,*CH,*COMe; the melting pointsgiven by these two authors differ, however, considerably. Thebehaviour of succinic pinacone as a tertiary alcohol is illustrated byits behaviour towards fuming hydrochloric acid or acetyl chloride ;these reagents convert it into the corresponding dichlorodimethyl-hexane, CMe,Cl*CH,*CH,*CMe,Cl.Bouveault and Locquin4 have published a summary of their in-teresting work on the action of sodium on esters of the aliphatic seriesand several new results have also been added.It was shown byBouveault and Blanc in 1903 that esters may be reduced to thealcohol corresponding to ths acid from which the ester is derived byaction of sodium in alcoholic solution. Amy1 acetate, for example,yields ethyl alcohol, methyl butyrate, m-butyl alcohol, and methyloctoate gives m-octyl alcohol. The action may even be applied toesters of unsaturated acids, oleyl alcohol, for instance, being obtainedfrom ethyl oleate.When the dry ester is added slowly to metallic sodium in dry ether,the sodium becomes, after a time, converted into a yellow powder, andthis product when decomposed by water yields a ketone-alcohol of thetype R*CO*CH(OH)*R ; for these compounds the authors suggest thegeneral name “acyloins.” The changes are considered by the authorsto take place as follows :R(ONa)C:C(ONa)R + 2EtONa + 4H,O =ZR*CO,Et + 4Na = R(ONa)C:C(ONa)R + 2EtONa and4NaOH + 2EtOH + R(OH)C:C(OH)R,Bcc.trccz.. chim., 1906, 143, 20.Bull. SOC. cJii)n., 1906, [iii], 35, 629, 636, 637, 641, 643, G46.Compt. m i d . , 1906, 143, 20.8 L O C . c i f . , 496ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 83the latter compound then irnniediately undergoing tautomeric changet o R*CO*CH(OH)*R. A large number of these acyloins have beenprepared and examined by the authors; the formation of the firstmember -methylacetol-has been proved to take place in this generalreaction, but the method is not suitedfor its preparation, owing to thesolubility in water and instability of the substance. When theacyloins are reduced, by means of sodium and alcohol, the productconsists of a mixture of two stereoisomeric modifications of a sym-metric disecondary glycol, R(OH)CH*CH(OH)R, and a secondaryalcohol, CH,R*CRH( OH).These products are readily converted intoketones, R*CO-CH,R, by heating with dilute sulphuric acid and byoxidation respectively, so that a general method is afforded of con-verting acyloins almost quantitatively into ketones of this type.On oxidation the acyloins yield a-diketones ; the usual oxidisingagents are not, however, suitable for this purpose, but the authorsfind 1 that the catalytic method of Sabatier and Seriderens gives goodresults.Diphenylketene, (C6H,),C:C0, was obtained by Staudinger in 1905by the action of zinc on diphenylchloroacetyl chloride.The sameauthor and Klever have now prepared the corresponding dimethylderivative, (CH,),C:CO, by acting with zinc on bromoisobutyrylbromide in ether or ethyl acetate solution. The pure substance is amobile liquid, which is stable a t - ZOO, but readily polymerises at t b eordinary temperature, giving a white substance which appears t o bethe diketone, [(CH,),C:C0I2. With water it gives isobutyric acid,and with aniline and phenylhydrazine it produces the anilide andphenylhydrazide respectively of isobutyric acid, Oxygen converts itinto a white explosive powder, which is perhaps a peroxide,Synthesis and Condensation of Fovnaucklehyde.The much-disputed question as t o the reduction of carbonic acid,directly or indirectly, t o formaldehyde is still receiving much atten-tion.With the object of throwing further light on this question and onthe nature of carbon dioxide assimilation, MT.Lob 4 has made an ex-tensive study of the behavionr of various g;rseous mixtures when theseare submitted to the influence of the silent discharge.5Amongst the many interesting results which were obtained, the fol-lowing may be mentioned.B d l , Xoc. chim., 1906, [iii], 35, 650.Lzer., 1906, 39, 968.Zeit. Elckti*oc?ie?n., 1905, 11, 745, mid 1906, 12, 282.C o i n p ~ c Collie, Aiiii. IL’cpo~l, 1905, 71.a A m . fiepoyt, 1905, 7084 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.It is shown that a mixture of carbon dioxide and water-vapour can,under the influence of the silent discharge, yield formaldehyde, thechanges probably being :(1) 2C0, = 2CO + 0,, (2) CO + H,O =CO, + H,, and (3) CO + H, = H*CHO.The author regards this as the first experimental proof which hasbeen given of the production of formaldehyde as a direct reactionproduct of carbon dioxide.The yield of formaldehyde is increased ifthe oxygen is removed from the sphere of action by means o€ reducingsubstances such as salicylaldehyde, pyrogallol, or chlorophyll. Muchlarger quantities of formaldehyde were obtained when a mixture ofmoist carbon monoxide and hydrogen was employed, and in this casethe author was able to make the important additional observation thatglycollaldehyde is formed as well. It is possible that the glycoll-aldehyde results from the condensation of formaldehyde.' But on thewhole it appears more probable that the initial product is an unstablereactive compound, H,CO, which may perhaps be a tautomeric labi,leform of formaldehyde, such as H-+-OH.It is further shown that methane results, in small quantity, when amixture of carbon monoxide and excess of hydrogen is similarlytreated. Losanitsch and Jovitschitsch have already observed that,under siinilar conditions, a mixture of methane and carbon monoxidegives rise to acetaldehyde, aud although the direct hydrogenisation ofacetaldehyde to ethyl alcohol, under the influence of the silent dis-charge, has not yet been accomplished, the change may fairly beassumed as a step in the natural assimilation process, Finally, it isshown that a mixture of ethyl alcohol, water, and carbon dioxide,when subjected to the action of the discharge, gives, after evapora-tion, a sugar which, from the character of its osazone, appears tobe p-acrose. The latter arises, doubtless, from the condensation ofglycollaldehyde.It will be observed t h a t the final change hererepresent's the converse of that in alcoholic fermentation,BC,H,*OH + 2C0, = C6HI2O6.Glycollaldehyde is obtained when carbon monoxide is substituted forthe dioxide, and also from a mixture of. acetaldehyde and carbonmonoxide. From a general consideration of the results obtained, theauthor is of opinion that the natural synthesis of sugars from carbondioxide may arise in two different directions. The initial unstableproduct above referred to results from the change CO,+H,O=H,CO + 0,.This product may on the one hand undergo polymerisa-Coiiipare Yechmann, Ber., 1897, 30, 2459. LOC. cit., 135ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 55tion into glycollaldehyde and higher sugars; if the velocity of con-densation is great as compared with the tautomeric change toformaldehyde, the latter may not actually be formed at all. On theother hand, the initial product may break up in various directions,giving rise to carbon monoxide, hydrogen, methane, &c., and. from theseacetaldehyde and ethyl alcohol, and finally sugars, may result in tliemanner above indicated.For the qualitative recognition of formaldehyde in the experimentshere described the author employs the reaction of Pilhashy, whichdepends on the yellowish-green colour which is given on addition ofa few drops of phenylhydrazine, a drop of concentrated sulphuric acid,and heating.Glycollaldehyde was identified by its phenylosazone,oxidation to glycollic acid, condensation to tetrose and hexose, andalso by the nitropheny1osazone.lRuss 2 shows that carbon monoxide and hydrogen are produced whenformaldehyde vapour is subjected to the action of the silent dischargeat 150'.Bach, it will be remembered, in 1893 stated that by passing a streamof carbon dioxide through solutions of uranyl acetate which wereexposed to direct sunlight he obtained a violet precipitate which whenexposed became yellow, and was transformed into a mixture of uranousand uranic hydroxides, together with a trace of ft brownish substancewhich he considered t o be uranium peroxide.He proposed to explainthis result by assuming that formaldehyde and percarbonic acid arefirst formed, and that the uranium percarbonate which results thenundergoes decomposition into uranium peroxide and carbon dioxide.I n a later experiment he substituted a salt of dimethylaniline for theuranium acet .tte, and considered that the production of formaldehydewas confirmed by the formation of tetramethyldiaminophenylmethane(Trillat's test). Euler in 1904 repeated these experiments, and statedthat a similar precipitate is obtained from the uranyl acetate solutionwhen a current of hydrogen or nitrogen is substituted for carbondioxide, and also that in the experiment with dimethylaniline noreaction is obtained if the reagent is carefully purified.The currentof gas, in the experiments with uranium,"appears only to be instru-mental i n removing oxygen.state that they have confirmed Bach's (earlier)results, but that the decomposition is extremely small even after threeweeks' exposure. They also made similar experiments with liquefiedcarbon dioxide and uranium acetate solution in sealed tubes. I n thiscase they obtained formic acid and a violet precipitate apparently con-Bach3 has since confirmed this view,Usher and Priestley1 Wohl and Neuberg, Rw., 1900, 33, 3107.2 Zeit. Elektrochewi., 1906, 12, 412.4 Proc. Aoy. SOC., 1906, 77, 369, and 78, 318.Be?.., 1906, 39, 167286 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.taining uranium peroxide, but no formaldehyde.Since there areobvious objections to using an organic substance as sensitiser, theyrepeated the experiments, substituting uranyl sulphate for the acetate.The results obtained in this case were similar ; no formaldehyde wasdetected, but after evaporation of the solution and separation of theformic acid a brown syrup was obtained, which had a bitter taste andreduced Fehling’s solution. A similar product was obtained by allowinga solution of formaldehyde to stand for some time in presence of uranichydroxide. The authors consider that this product resembles Butleroff’smethylenitan ; it does not, however, react with pheny1hydrazine.lFrom these results, and from other observations, the authors con-clude that formaldehyde is produced as a transitory intermediate pro-duct.The action of chlorophyll as serisitiser was also investigated :glass plates which had bean coated with gelatine and painted with asolution of chlorophyll in light petroleum, or other solvent, were placedin a bell-jar containing moist carbon dioxide, and exposed to light. Thechlorophyll became bleached, and the gelatin aft,erwards gave a pinkcolour with Schiff’s reagent. An aqueous solution of this exposedgelatin gave, on distillation, indications of formaldehyde by the testsmentioned below. The remaining observations deal principally withthe problem of carbon assimilation i n green plants, and will be con-sidered elsewhere.With reference to the disputed question as to theactual detection of free formaldehyde in the living plant, the authorsconsider that it is useless to look for the aldehyde in healthy assimi-lating leaves, since it there undergoes immediate condensation underthe influence OF protoplasm. Bat after killing the protoplasm, anddestroying enzymes, by immersion in boiling water, leaves which wereexposed to sunlight in water saturated with carbon dioxide gave, whensubjected to steam distillation, a solution containing formaldehyde.For the identification of formaldehyde in these experiments theauthors rely principally on the methylene-aniline test, and also on theformation of hexamethylenetetramine, which they identify by treat-ment with bromine,z but details of this are not given.I n connexion with the foregoing statements it would be well torefer to the criticisms of Euler 3 on the very similar experiments ofPolacci, who in 1899 stated that he obtained a distillate containingformaldehyde from leaves which had been exposed to sunlight andextracted with water.H.and A. Euler have continued their studies on the behaviourof formaldehyde towards various bases.* As previously stated,5Compare Loew, J. pr. Chem., 1888, 37, 205 ; and Fischer, Be?.., 1886, 21, 991.Legler, Bcr., 1885, 18, 3343, and Horton, ibid., 1888, 21, 1999.Ber., 1904, 37, 3412.Aim. Report, 1905, 74.LOC. cit., 1906, 39, 36 and 39ORGANIC CHEMISTRY-ALlPHATIC DIVMION 57the action takes place in two directions, the condensation tosugars and the production of formates and methyl alcohoI.It wasshown that the power of different bases in bringing about the con-densation does not stand in any simple relation to the rate a t whichformates are produced. Sugar condensation does not appear to beginuntil a part of the aldehyde has been changed to formate and methylalcohol ; on the other hand, the concentration at which sugar formationcommences is not influenced by the amount of formate present.Reasons are given for considering that the production of formate ispreceded by the formation of a metallic “salt ” of formaldehyde,or ‘‘ formolate ” as the authors term it. From cryoscopic determina-tions with mixtures of soda and formaldehyde it is calculated that thedissociation constant of formaldehyde, behaving as an acid, isI n making estimates of the nature and quantity of the sugars pro-duced by condensation it is evident, as the authors point out, thatstrong alkalis are objectionable as condensing agents, since they tend todestroy or modify the products in question.Advantage is thereforetaken of the observation that the condensation of formaldehyde may bebrought about by means of calcium carbonate; although the action ofthis reagent is slow, it has the advantage that the change is effected inpractically a neutral solution, and the formate production appears totake place to a less extent.By heating a litre of 2 per cent. formaldehyde with 10 grams ofcalcium carbonate for several hours, precipitating the calcium salts withalcohol and ether and distilling the remaining solution, a syrup was leftfrom which, by the action of phenylhydrazine acetate, a yield of osazonew t ~ s obtained corresponding to 60-80 per cent. of the formaldehydeemployed.The crude mixture of osazones so obtained yielded, afterpurification with benzene, a definite yellow crystalline product whichmelted at 166O and had the composition of a pentosuxone. The existenceof a, pentose in the crude condensation product from formaldehyde wasindicated in one of the analyses given by Fischer in 1888. Neubergalso, in 1902, obtained a phenyl methyl osazone from crude formosewhich melted a t 1 3’i0 and corresponded in composition to a pentosazone ;this was considered by the author to be derived from a keto-pentose.The pentose obtained in the present case might be either arabinose orribose ; the latter appears, however, to be excluded by the fact that onreduction of the original syrup with sodium amalgam no adonite couldbe obtained.By oxidation of the syrup with bromine, or nitric a.cid, aconsiderable quantity of trihydroxybutyric acid was produced ; fromthese results, anci from the behaviour of the syrup with resorcinol andwith phenylmethylhydrazine, the authors conclude that the principalcondensation product of formaldehyde, under the above-mentioned con-1.4 x 10-1488 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ditions, is i-arabinoketose. From the part of the crude osazone whichis more soluble in benzene a Aexosazone melting at 140-142O wasobtained.If the condensation is interrupted when about half the formaldehydehas disappeared, and the unaltered formaldehyde is then removed bymeans of pdihydrazinodipheny1,l the remaining solution gives, withphenylhydruzine acetate, a resinous oil from which, by treatment witha mixture of pyridine and light petroleum, a crystalline osazone melt-ing at lSOo was obtained.This product corresponds in compositionand properties to the osazone of glycollaldehyde. I n the process of puri-fying this osazone by means of pyridine and light petroleum, a sub-stance was deposited from the solution, after some weeks, in the form ofcolourless scales melting at about 162'; the composition of this pro-duct corresponds with that of the hitherto unknown glycollaldehydehydrazone.I n addition to the above-named substances, the presence ofdihydroxyacetone was indicated by means of phenylmethylhydrazine ;glyceraldehyde appeared t o be absent.I n reference to the experiments which are here described,Loew points out that in 1888 he succeeded in bringing about the con-densation of formaldehyde by means of metallic tin containing somelead, SO that the change here occurred in a wholly neutral solution.Heconsiders that tho result obtained by Euler with calcium carbonate wasdue to the initial production of some calcium formate, since he hasalready shown that the acetates of calcium, lead, or magnesium can act,although slowly, as condensing agents in this way.That formaldehyde may arise as a degradation-product of sugar isconfirmed by the recent experiments of Trillat.3 When sucrose isheated to loo", or higher temperatures, formaldehyde is produced, thequantities obtained varying from 0.2 to 5.7 per cent.The larger amountsare obtained if the sugar is heated in contact with copper foil, Thepresence of air is not necessary, although the yield is smaller when airis excluded. Benzaldehyde, acetone, methyl alcohol, acetic acid, acet-aldehyde, and phenol derivatives are also produced. Formaldehyde isfound not only in the evolved gases, but also in the residual caramel, afact which perhaps accounts for the antiseptic properties of caramel. Itwould appear that a portion of the formaldehyde polymerises and formsprodiicts analogous t o methylenitan, and caramel itself may perhaps bethe result of such changes.The caramel-like properties of the productsobtained by heating formaldehyde with alkalis are well known.Neuberg, Ber., 1899, 32, 1961. Loa. cit., 1906, 39, 1592.3 Zcit. Vcr. Iliibcnozck-lnd., 1906, 95 ; and Compt. rend., 1906, 142, 454ORGANIC CHEMISTRY-ALIPHATLC DIVISION. 89Carbohydrates.Apiose is the name given by Vongerichten (1900) to a new pentosewhich is contained, as a disaccharide with a-glucose, in the glucosideapiin found in parsley seeds. The same author and Mullerl now showthat the sugar exists also in the green parts of parsley as well as in theseeds. This pentose, when oxidised with bromine or nitric acid, yieldsthe monobasic apionic acid, and, when further oxidised with nitric acida dibasic acid is produced which is isomeric with trihydroxyglu taricacid ; the relationships of the latter indicate that it is hydroxymethyl-tartaric acid :[ CH,OH] , : C (OH) CH (OH) C HO-+[ C H,OH] : C: ( 0 H) C H( 0 H) C0,HJVith phenyl benzyl hydrazine apiose yields a colourless crystallinehydrazone, from which the sugar may be recovered unchanged by meansof formaldehyde.Rhodeose is a methylpentose discovered by Votocek in 1900, and isobtained by hydrolysirig convolvulin with dilute sulphuric acid ; theglucose which is also present can be removed by fermentation, sincerhodeose is non-fermentable.This sugar has been further studied byVotoEek and Bulir.2 It is shown that on reduction by means of sodiumamalgam it yields a corresponding polyhydric alcohol-rhodeitol-which was obtained in white crystalline plates.This substance is notoxidised by the sorbose bacterium, and it therefore follows thatits configuration must be represented by the formulaOH B OH*CH2- $I - F-[CH*OH],*CH,,H OHor its image.3 A similar configuration must apply to rhodeose. Whenrhodeose and its optical antipode fucose are mixed in equal proportionsand reduced by sodium amalgam the racemic form of the polyhydricalcohol (1.-rhodeitol or T-f ucitol) is obtained.The trisaccharide melezitose, or melezitriose, has hitherto beenregarded as containing three dextrose residues, yielding, it was thought,three molecules of this sugar on hydrolysis. Tanret4 now shows thatwhen heated with 20 per cent.acetic acid melezitose yields a mixture ofdextrose and turanose; C12Hz20,,. The latter can be obtained, afterremoval of the dextrose by fermentation, in the form of hygroscopic,non-crystalline granules containing alcohol, which may be purified byBw., 1906, 39, 235. Zeit. Zzsckerind. Bohm, 1906, 30, 333.3 Compare Bertrand, A m . Report, 1904, 64. Compt. rend., 1906, 142, 142490 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.heating to 100’. Turanose is readily hydrolysed by mineral acids, andyields a mixture of equal parts of dextrose and lmwlose.According to Ofner,] phenylethylhydrazine reacts with glucose inneutral solution to give the hydrazone, but iu acetic acid solution ityields the corresponding osazone ; the change takes place more readilythan with phenylmethylhydrazine, and the yield is about 60 per cent.Fructose gives about the same yield.This behaviour of glucose affordsa further proof that unsymmetrica 1 secondary hydrazines are able togive rise to osazones with aldoses as well as with ketoses.2Blaquenne found that reducing sugars, when treated in a uniform waywith phenylhydrazine, showed considerable differences both in the yieldof osazone and in the time required for precipitation; upon thesedifferences nlulliken has since based a scheme for the identification ofcertain pure sugars. Sherman and Williams have now made furtherexperiments in this direction, especially with regard to the influence ofdilution and of the presence of other sugar$.I n the case of glucoseand fructose the time required for precipitation varies with the con-centration, and is nearly constant for a given dilution, but withfructose the time is about one-third of that required with glucose.Prom invert sugnr the osazone is precipitated almost as quickly as fromfructose. I n solutions containing about 0.1 per cent. of glucose theprecipitation is considerably accelerated by the presence of 1 per cent.,or more, of sucrose, but only slightly by 5 per cent. of raffinose. Thepresence of maltose or of lactose exerts a retarding influence on theprecipitation of glucosazone.It would appear that no direct method has hitherto been devised forthe addition of hydrocarbon residues to the carbon chain in pentoses orhexoses, and with this object in view Paal and Hornstein 4 havestudied the behaviour of Grignard’s reagent towards derivatives ofglucose such as the penta-acetate and the bromoacetyl derivatives.Thelatter compounds, however, show but little tendency to react, probablybecause the aldehydic oxygen of the original glucose is now (‘ ether-linked.” But it appeared that the desired result might be attained byemploying the lactones of the corresponding monobasic acids producedby oxidation of the aldose sugars ; Houben (1904) has, in fact, alreadyshown that tertiary alcohols are obtained by action of Grignard’sreagent on lactones. The lnctone of d-gluconic acid is not itself suitablefor this purpose, since it is not soluble in ether or other solvent appro-priate to Grignard’s reaction, but by acting on d-gluconic acid withacetic anhydride a product is obtained which dissolves easily in amixture of ether and benzene.This product, probably a tetra-aceto-lactone, was not isolated in a pure condition, but was acted on byMonntsh., 1906, 27, 75. Coniliare Ann. &port, 1904, 65.Ber., 1906, 39, 1361. 3 J. Amer. Chcni. SOC., 1906, 28, 630ORGANlC CHEMISTRY-ALIPHATIC DIVISION. 91magnesium phenyl bromide in excess. After decomposition of theresulting products with dilute sulphuric acid the authors obtained, inaddition to diphenylmethylcarbinol, a substance which crystallised inwhite needles ; this product is shown to be a hexahydroxydiphenyl-hexane or diphenylhexitol. From the mode of formation it wouldappear that the configuration of the latter substance is to be repre-sented by the formula,OH H OH OHI I I IOH*CPh,*C -I: -C-C* CH,*OH,I I I I H O H H Hassuming, of course, as is probable, that no steric rearrangement hasoccurred in the above-rn-entioned changes.The new compound is there-fore to be regarded as 1 : 1-diphenyl-d-sorbitol.I n a later communication1 the authors state that they have isolatedthe lactone of tetra-acetyl-d-gluconic acid as a gummy mass. Theyhare also somewhat modified the details in the preparation of diphenyl-d-sorbitol so as to improve the yield.Paal and Weidenkaff have since made a similar synthesis from thelactone of tetra-acetylgalactonic acid, and have obtained in this wayanother diphenylhexitol. Since the steric configuration of this pro-duct is somewhat uncertain, the authors provisionally name it1 : 1 - diphenyl-d-gdactohexitol.LIditol,H OH H OHI I I I OH*CH,*C--C-C--C*CH,*OH,I I I I OH H OH Hwas obtained as a syrup by Fischer and Fay in 1895 from xylose bytreatment with hydrocyanic acid and reduction of the resultingI-idonic acid or its lactone with sodium amalgam.Bertrand andLanzenberg 3 have now succeeded, by a modification of this method, inobtaining the pure substance in a crystalline state.A paper of considerable interest has been published by Schade4 inwhich an acl,ount is given of a series of investigations on the behaviourof sugar solutions towards alkalis. From the results obtained theauthor was led to believe that it was possible, in a purely chemicalway, and without the use of enzymes, to transform dextrose orlzevulose quantitatively into ethyl alcohol and carbon dioxide.It hasbeen previously shown by Framm, in 1896, that the yellow or browncolouring which is usually observed during the action of alkalis on-I Zeit. ph.ysika1. Chem., 1906, 57, 1,Ber., 1906, 39, 2823. LOC. cit., 2827.8 Compt. rend., 1906, 143, 29192 ANNUAL REPORTS ON THE PROGRESS O F CHEMISlRY.sugar solutions may be prevented altogether if a current of air ispassed through the mixture. Schade finds that a similar result maybe obtained by operating under reduced pressure or by the addition ofhydrogen dioxide. The final products obtained when the first methodsare employed appeared t o be formic acid and acetaldehyde, the latterbeing indicated in the distillate. When hydrogen dioxide was addedthe products were formic acid and acetic acid. The yellow or browncolouring appeared therefore t o be due to aldehyde-resin, resulting fromthe decomposition of acetaldehyde; if the latter was removed, asvapour or by oxidation, the solution remained clear.This view seemedto be supported by the observation that the colouring could alsobe prevented by the addition of substances which combine with acet-aldehyde, such as ammonia, bisulphites, or cyanides. Estimation of theformic acid and acetaldehyde (the latter as acetic acid in the hydrogendioxide experiment) appeared to indicate that the reaction of alkalison dextrose or lsvulose is to be represented quantitatively by therelationC,H,,06 = 2H*CO,H + 2CH,*CHO.The question then suggested itself whether i t might not be possible tobring about a further reaction betweer, these products in such amanner as to transform them into ethyl alcohol and carbon dioxide.Deville and Debray in 1874 showed that formic acid under thecatalytic influence of rhodium-black is resolved into carbon dioxide andhydrogen ; the latter then, ‘‘ in the nascent state,” might react withacetaldehyde, converting it into ethyl alcohol.This idea was successfullycarried into effect by the author. A 5 per cent. solution of sodiumformate, made faintly acid with acetic acid, was warmed to 60° in con-tact with a small quantity of rhodium-black (colloidal rhodium, pre-pared by Bredig’s method, was found to be ineffective), and thecalculated quantity of acetaldehyde, in the form of vapour, was passedgradually into the mixture; in this way a yield of 60-70 per cent.ofethyl alcohol was obtained after three hours. From these results t.heauthor concluded that the resolution of sugar into alcohol and carbondioxide is a spontaneous process which is accelerated by catalysts. Manyanalogies are pointed out between these purely chemical operations andordinary fermentation. The final products are reached in the one caseby the agency of two different catnlysts, namely, hydroxyl ions andrhodium ; in the other case by zymase. I n both cases the reactionvelocity is proportional to the mass of the catalyst or of the enzyme;the changes take place in absence of oxygen and are influenced by thepresence of minute traces of foreign substances, by concentration ofthe solution and by the accumulation of the reaction-products.As inyeast fermentation there appears to be, in the purely chemical processORGANIC CHEMISTRY-ALIPHATIC DIVISION. 98an '' optimum " temperature which, in the latter case, lies between40° and 80'.It is disappointing to learn from a subsequent communication byBuchner, Meisenheimer and Schade 1 t h a t , on repeating certain ofSchade's experiments, they have obtained entirely different results, andthat the conclusions arrived at by this author can no longer be main-tained. The volatile aldehydic substance which was regarded as acet-aldehyde appears to have been furfuraldehyde, and is only produced insmall quantity.The yield of formic acid is greater than that abovestated, and, in addition, there is formed trihydroxybutyric acid, glpcollicacid, and probably a mixture of hexonic acids, &c. The authors considerthat formic acid is not a primary product in this decomposition, but thatglyceraldehyde is first formed; this under normal conditions would betransformed into methylglyoxal and so into lactic acid; but in thepresent case it might split up into three molecules of formaldehyde,which would then be oxidised by the hydrogen dioxide as shown byBlank and Finkenbeiner.2 The yellow or brown colouring abovereferred to is caused, the authors consider, by some non-volatile andeasily oxidisable hydroxyaldehyde, possibly glyceraldehyde.Purdie and Young3 find that when methylrhamnoside is completelymethylated by means of silver oxide and methyl iodide it yieldstrimethylrhamnoside, which, on hydrolysis, gives trime thylrhamnose.Dimethylrhamnose is similarly obtained from acetonerhamnoside.Yimethyl- and trimethyl-rhamnose display the ordinary properties ofreducing sugars and give crystalline phenylhydrazones.Trimethyl arabinose is obtained in a similar way from Fischer'sa-meth~larabinoside.~Irvine and Moody 5 shorn that when solutions of the equilibriummixture of tetramethyl glucose in ordinary organic solvents are cooledfrom + 20' to - 20°, the specific rotations undergo very little alteration,and, on again heating to the initial temperature, the original valuesare exactly obtained.When, however, an alkyl iodide is used assolvent the specific rotation at first slightly increases and then rapidlydiminishes, as the solution is cooled: On reheating to 20° distinctdownward mutarotation mas observed before the initial value wasreached. The same regularities were shown by solutions of molecularproportions of the sugar and alkyl halide or hydrogen chloride in carbontetrachloride. The authors consider that these results point to theformation of oxonium compounds of the sugar with alkyl halides, andthe a-form of the aldose appears t o be more reactive than the/3-isomeride. Tetramethyl a-methylglucoside also behaves abnormallyBer., 1906, 39, 4217.Truns., 1906, 89, 1194.LOG.cit.,1898, 31, 2979.Purdie and Rose, loc. cit., 1204.LOC. cit., 157894 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.when cooled in ethyl iodide solution, but the P-isomeride shows noindication oE combining with the solvent.Amongst other papers which have been published in connexion withthe chemistry of sugars, attention should be drawn to the work ofGaldwell1 on the siicroclastic action of acids, in which the author dis-cusses the important question of '' weight-normal ') versus '' volume-normal " solutions ; also a paper by Rosaxioff,2 which contains acriticism of Fisaher's d and l classification of stereoisomerides andsuggests a revised nomenclature which will include also the poly-hexor?es, These papers will be more appropriately referred to in thesections on physical chemistry and stereochemistry.The highest product of the acetylation of cellulose was a t one timeconsidered t o be a tetra-acetate, C,H,O(OAc),.The existence of sucha derivative would not be in accord with the constitutional formulaproposed- by A. G. Green, which in other respects gives a very completeindication of the chemical relationships of cellulose.3 This authorand A. G. Perkin have reinvestigated this supposed tetra-acetate,and have determined the acetyl groups by three different methods,and -they come to the conclusion that the compound in question isbeyond doubt a triacetyl derivative. They admit that higher acetylatedproducts may be obtained if condensing agents such as zinc chlorideor sulphuric acid axe present, but these, they consider, are derivativesof the hydration products of cellulose and not of cellulose itself.Withregard to Green's constitutional formula, it is pointed out that it isonly intended to represent cellulose in its simplest o r unpolymerisedform, in which, for instance, it may be present in a n ammoniacalcupric solution. The cellulose of fibres may be regarded either as aphysical aggregate of these simple molecules or as a chemical polymeridemade up of a number of C, complexes, of the structure suggested,united together by means of their oxygen atoms.Cross and Bevan, as pointed out in the Annual Report of last year(page S9), regard the matter from a different standpoint, and theirviews are expressed a t length in their recently published 12esearclbe.s onCellulose, II., 1900-1905.Thesolnble acetates were prepared by various different methods, such asthose of Cross and Bevan, Lederer and Bayer, and in all cases thesame product was obtained, namely, the triacetate, C,H70,(0Ac),.The author considers, however, that it is questionable whether atriacetate of normal cellulose exists, and that the products obtainedare rather to be regarded as acetates of a series of hydrocelluloses ofJ.A m r . Chein. Soc., 1906, 28, 114.Trans., 1906, 89, 811.The cellulose acetates have also been examined by H. Ost.5Proe. Eoy. Soc., 1906, 78, 272.See Anii. Xeport, 1904, 69.Zczt. mcyeiti. C'hem., 1906, 19, 99ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 95various degrees of degradation.He estimates the acetyl groups inthese compounds by hydrolysis with dilute sulphuric acid and distilla-tion of the resulting acetic acid with steam, and considers that thesupposed existence of the tetra-acetate is accounted for by the highresults obtained when the saponification is effected by alcoholic potash,a process which may give rise to the production of acids a t the expenseof part of the cellulose.Glucosides.I n order to establish the structural formulze of glucosides, it hasbeen the custom in the majority of cases to rely only upon a studyof the products obtained on hydrolysis ; in comparatively few instanceshas the evidence obtained in this way been supplemented by a directsynthetical preparation of the glucoside itself.I n order to obtainevidence bearing upon the linking of the sugar residue, Irvine andRose show that it is necessary to prepare derivatives of the glucosideand to study the hydrolysis of the compounds so obtained. Alkylatedglucosides are well adapted for such work owing to the stability ofthe alkyloxy-groups, the occurrence of secondary changes duringhydrolysis being in this way largely precluded. It has previously beenshown by Purdie and Irvine (1903) that when the crystalline tetra-methyl glucose, prepared from either the a- or P-tetramethyl gluco-side, is oxidised, it is converted into tetramethylgluconolactone, thisresult indicating that the parent glucosides possess the y-oxidic link-ing.Similar reactions have now been applied with the object ofestablishing the complete structural formula of a natural glucoside,salicin being selected as a typical example. Previous investigationshave proved salicin to be saligenin /3-glucoside, and its syntheticalformation from helicin proves that the two parts of the molecule areunited through the phenolic hydroxyl group. The authors have nowobtained a pentamethyl salicin by the usual method of alkylation withmethyl iodide and silver oxide; it is a colourless crystalline compound,practically insoluble in water, but readily soluble in organic solvents.The hydrolysis of this compound presented, however, considerabledifficulty, and the following synthetical method was therefore devisedit1 order to prove the y-oxidic linking.Saligenin and tetramethylglucose mere condensed t o saligenin tetramethyl glucoside by heatingwith hydrochloric acid in benzene. The remaining hydroxyl groupwas now alkylated by the silver oxide method, and a compound wasthus obtained, which proved to be identical in every way with thepentamethyl salicin prepared, as described above, from the naturalg 1 11c osi cl e .Trans., 1906, 89, 81496 ANNUAL REFORTS ON THE PROGRESS OF CHEMISTRP.Neilson 1 finds that the hydrolysis of salicin and amygdalin can bebrought about by the catalytic influence of platinum black. I n thecase of salicin, the hydrolysis could be conducted under conditionsexactly comparable with those of enzyme action, but with amygdalinit was necessary to use open flasks since the hydrocyanic acid producedin the reaction had a strong inhibitive influence on the catalysis.According t o Loew and AsbY2 platinum black has the power of con-verting maleic acid into fumaric acid ; and Neilson states that starchniay be hydrolysed by platinum black.A substance is contained in the cell sap of the leaf epidermis ofvarious plants which gives a blue colour with iodine.The colour dis-appears on warming, but returns on cooling, as in the case of starch ;it is not, however, confined to well-marked grains, but extends m i -formly throughout the cell as a fine blue precipitate. The substancewhich gives this reaction, often called '' soluble starch " by botanists,has now been isolated by Barger,4 and proves to be a glucoside.Itcrystallises in microscopic needles, has the composition C21H2t012,2H20,and is optically active. The name saponarin is adopted for this newglucoside in reference to the source (5'aponaria o$icinc&s) from whichit was prepared, leaving open the question of its probable identity withthe " soluble starch " of other plants.When hydrolysed with acids it gives rise to glucose and vitexin, acolouring matter which was obtained by A. G. Perkin (1898) from aNew Zealand dye-wood.Auother colouring matter is produced at the same time, which appearsto be isomeric with, or closely related to, vitexin; for this the authorsuggests the name saponaretin.[It may be mentioned here that the mych-disputed question as tothe nature of the blue substance produced from starch and iodine hasbeen attacked by Padoa and Savark in a new way.They investigatethe changes in electric conductivity of a solution of iodine in potassiumiodide which are caused by addition of given quantities of starch, andthey conclude that the blue substance is a n additive compound ofiodine, starch, and potassium (or hydrogen) iodide, the starch andiodine being present in the ratio 4C,H,,O, : I.]Further studies of the occurreuce of cyanogenetic glycosides havebeen made by Dunstan, Henry, and AuldYG Guignard,7 H6bert,8 andBert~-and.~Amer. J. Physiol., 1905, 15, 148.Amer. J. Physiol., 1906, 15, 412.Gazxetta, 1906, 36, i, 313.Bull. Coll. Agr. Tckyd, 1906, 1.Trans., 1906, 89, 1210.ti Proc. Eoy.Soe., 1906, 78, 145, 152.7 Compt. rend., 1906, 142, 545 ; 143, 451.1ti Bull. Xoe. ehim., 1906, 35, 919. Conzpt ?.end., 1906, 143, 832ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 97Acids.Thorpe and Higson 1 describe a new method of obtaining succinicacid and its alkyl derivatives which is based upon the condensation ofethyl sodiocyanoacetate with the cyanohydrin of either an aldehyde ora ketone, and subsequent hydrolysis of the resulting ethyl ester. Thegeneral reaction is indicated by the following changes :CO,Et*C(CN)NaH + HO*C(CN)R -+ CO,Et*C(CN)Na*C<CN)R + H20and CO,Et*CH(CN)*CR,(CN) -+ C02Et*CH2*CR2*C02Et.R RFormaldehydecyanohydrin and ethyl sodiocyanoacetate, for example,yield succinic acid, and benzaldehydecyanohydrin, in a similar way,gives phenylsuccinic acid.When, however, the condensation of formaldehydecyanohydrin andthe cyanoacetate is brought about in hot solution, the product is ethyla$-dicyanoglutarate, and from this product glutaric acid is obtained onhydrolysis.The condensation-product CO,Et*CNa(CN)*C(CN)R, which is firstformed in the above reaction is stable in presence of cold water, sothat it is not affected by the small quantity of water produced in thechange. I f this product is then directly acted on by alkyl iodides, thehigher alkyl derivatives of succinic acid can be obtained :CN*CNa(CO,Et)*C(CN)R, + RI -+ CN*CR(CO,Et)*C(CN)R, +NaI -+ C02H*CHR*CR2*C02H.I n this way, for example, acetonecyanohydrin, when condensed withethyl sodiocyanoacetate, gave a product from which, by the action ofmethyl iodide, trimethylsuccinic acid was prepared.It.Meyer and Bock2 have sought for an improved method ofobtaining isosuccinic acid, since the directions usually given for themalonic ester synthesis did not yield a pure product, and thepreparation from a-bromopropionic acid and potassium cyanide wasfound to be unsatisfactory. An attempt to attain the desiredobject by means of Crignard’s reaction-that is .by acting withmagnesium on a-bromopropionic ester in order to obtain the compoundCH,*CH(MgBr)*CO,Et and treating this product with carbon dioxide-gave a negative result. Finally, the authors consider that the bestmethod of preparation consists in first obtaining pure isosuccinamide(from the impure ester) and hydrolysing this by means of sodiumhydroxide.The properties of isosuccinic acid and its salts, cptc., havebeen further studied and its heat of combustion re-determined.Trans., 1906, 89, 1456.VOL. 111.Annalen, 1906, 347, 93.98 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Resnlts of considerable importance have been obtained by Lossenand his colleagues1 in a series of investigations on the halogenderivatives of aliphatic acids. It will only be possible, in the limitedspace here available, to give a brief indication of some of these resultswhich are of more general interest.Chloro- and bromo-acetic acids when boiled with bases yield not onlyglycollic acid but also diglycollic acid, the results depending on thenature and proportion of base. Trichloro- and tribromo-acetic acidswhen similarly treated give chloroform and carbon dioxide, or, underother conditions, a formate, chloride or bromide, and carbonate.a-Bromopropionic acid yields both lactic and acrylic acids, whereas/3-bromopropionic acid gives hydracrylic and acrylic acids ; in the lattercase the proportion of acrylic acid is larger and the change takes placemore rapidly, contrary to what would be expected from Wislicenus’stheory.aa-Dibromopropionic acid gives pyruvic and a- bromoacry lic acidsand the so-called ‘‘ acryl colloid.” The latter, which appears to havethe composition (C3H40&, is probably a polymeride of pyruvicacid.ap-Dibromopropionic acid decomposes more rapidly than the aa-acid,and yields glyceric acid with a-bromohydracrylic acid and a smallquantity of pyruvic acid; according to theory, the aa-acid shoulddecompose more rapidly.Tribromosuccinic acid has hitherto been but little studied ; it wasobtained originally by Petri by the action of bromine on bromomaleicacid.His method of preparation presented, however, certain difficulties,especially as the solution obtained was evaporated at the ordinary tem-perature, an operation which may take some weeks. The authors haveconsiderably improved this method, and find that the acid may beprecipitated by passing hydrogen chloride into the solution. Whenboiled with caustic potash it yields dibromomaleic acid, and a similarresult is obtained when a benzene solution of the acid is heatedfor two hours, the yield then being almost quantitative.This resultagain is opposed to theory, since the formation of dibromofumaric acidwas to be expected :HCO,H*$l*Br CO,H*gaBr - HBr = Br C*CO,H Br C CO,H*BrDibromomaleic acid is also produced when dry ammonia acts on tri-bromosuccinic acid in absolute alcoholic solution ; but if aqueousAnnalen, 1905, 342, 112, 157 ; 1906, 348, 261ORGAKIC CHEMlSTRS-ALIPHATIC DIVISION. 99ammonia is gradually added to an aqueous solution of the acid, theammonium salt of bromofumaric acid results :3C4H30,Br3 + 14NH3 = 3C,H0,Br(NH4), + 6NH4Br + N,.By the action of chlorine water on the normal sodium salt offulnaric or maleic acid, the authors have obtained chloromalic acid,CO,H*CHCl*CH(OH).CO,H; i t was also obtained by the action ofsodium hypochlorite on the acid salt or of hypochlorous acid on thefree acids.Chloromalic acid when subjected to dry distillation, or when heatedwith concentrated hydrochloric acid, yields chloromaleic acid ; onreduction by means of zinc it gives malic acid.When an aqueoussolution of the acid is boiled, aldehyde and tartaric acid are produced :C,H,O,Cl+ H,O = C,H406 + HC1 and C4H,0,C1 = C,H,O + 2C0, + HC1.Bromomnlic acid was similarly prepared, and its behaviour is inalmost every respect analogous to that of the chloro-derivative.An acid of considerable interest is obtained by the action of alkalison chloro- or bromo-malic acid; when either of these acids is treated,a t the ordinary temperature, with caustic soda, the mixture allowed tostand, acidiged and extracted with ether and ethyl acetate, a crystallineproduct is obtained which melts at 203’ and has the compositionC4H405.Analysis of its salts, esters, chlorides, and arnide shows theacid to be dibasic. The absence of alcoholic hydroxyl is shown by thefact that both acetyl chloride and phenylcarbimide are without actionon the dimethyl ester. The authors therefore assign to this acid theconstitution O< CH*CozH I and name it fumarylglycidic acid. ItsCH*CO,H’formation from chloromalic acid is represented thus :C4H505Cl + 3KOH = C,H,O,K, + KCl + 3H,O.An aqueous solution of furnarylglycidic acid, when boiled, givesrise to racemic and i-tartaric acids, aldehyde and carbon dioxide.The authors have also studied the decomposition of bromomaleic andbromofumaric acids, and the preparation and reactions of acetylene-dicarboxylic acid.Experiments bearing on the constitution of fulminic acid by Wohlerand Theodorovits were referred to in the previous Bepoyt (pp. 98-99),from which it appeared t h a t fulminic acid is not formed from mono-carbon compounds by action of nitric acid and mercuric nitrate.Theseresults appeared to speak in favour of the double formula for fulminicacid, but Wohler’s measurements of the molecular weight and equiva-lent conductivities of sodium fulminate pointed to the single formulaHCNO.H 100 ANNUAL REPORTS ON THE PROGRESS O F CEIEMIS'I'RT.Nef, it will be remembered, regards fulminic acid as C:NOH orcarbonyl oxime.Jowitschitsch 1 bas again attacked this question, andconsiders that this formula is improbable for several reasons ; bearing inmind, for example, the reactivity of nitric acid with unsaturated carboncompounds, one would not expect an unsaturated mono-carbon com-pound to be produced, almost quantitatively, by the action of nitric acidon a saturated two-carbon compound. The author is inclined rather to7H:N.OI , which was proposed CH:N*O prefer the glyoxime peroxide formula,by Scholl,, and has therefore synthetically prepared a compound cor-responding to this constitution in order to compare its properties withfulminic acid.Y(C0,Et):N.b I wasC( C0,Et) :N* 0' The peroxide of diisonitrososuccinic ester,first prepared (from the nitrolic acid of ethyl acetoacetate), and this, bythe action of sodium hydroxide under stated conditions, gave rise to 'thesodium salt of glyoxime peroxide, from which the silver salts wereprepared.The di-silver salt closely resembles silver fulminate ; it isexplosive, and yields h) droxylamine by the action of hydrochloric acid,but differs from silver fulminate in being easily soluble in nitric acid andless explosive. By the action of hydrochloric acid on a nitric acidsolution of the silver salt, the free glyoxime peroxide was obtained insmall quantity as a yellow, acid liquid.Esters.Ethyl nitrogentricarboxylate, N( CO,Et),, was prepared by Diels in1903 by heating a mixture of ethyl chlorocarbonate and ethylcarbamate with sodium. Attempts to saponify this ester with alkaliswere not successful, since under these conditions i t splits up into ethylalcohol, carbon dioxide, and ethyl iminodicarboxy late, NH( CO,Et),.I n this case, therefore, both carbethoxy-groups remain attached tonitrogen, It is now shown by this author and Wolf 3 that a differentdecomposition occurs when the ester is acted on by dry ferric chloride,the products then being ethyl carbonate and ethyl carbimide-carboxyla t e :N(CO,Et), = CO(OEt), + O:C:N*CO,Et.Since the separation of these two substances is dificult, the authorssought a method of decomposition which would yield the latter freefrom inconvenient by-products, and they found that this object couldbe attained by heating the txicarboxylic ester with phosphoric oxide.LOG.cit., 1906, 39, 1686.1 ZL7L?LLLleIL, 1906, 347, 233. L'w., 1890, 23, 3505ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 101I n this case the by-products are ethylene, carbon dioxide, andwater :N(CO,Et), = 2C2H4 + CO, + H20 + 0:C: N*CO,Et.The foregoing observation led the authors to investigate the action ofphosphoric oxide on other esters with the view of ascertaining whetherreactions of a similar type could be effected, and with malonic esterthey have obtained results of considerable interest.lEthyl malonate was slowly distilled, at a pressure of 12 mm., over alarge excess of phosphoric oxide, distributed in glass wool and heatedto ahout 300O; the evolved gases were passed first through a well-cooled tube to remove any unaltered ester, and then into a vesselsurrounded by liquid air.The products obtained were ethylene, alittle carbon dioxide, and a substance having a very pungent odour,which proves to be a colourless liquid boiling at 7". By allowing themixture to boil at the ordinary temperature, the ethylene and carbondioxide are removed, and the new product is then vaporised and collectedin a tube cooled to - 60'. It is a very mobile, refractive liquidhaving an odour resembling that of acraldehyde or mustard oil. It burnswith a smoky blue flame. When treated with cold water it yields malonicacid, and with dry hydrogen chloride, ammonia, and aniline it givesrise to malonyl chloride, malonamide, and malonanilide respectively ;it behaves, therefore, as an anhydride of malonic acid.Analysis bycombustion with copper oxide and by explosion with oxygen, andmolecular weight determination by Hofmann's vapour-density method,show that the compound has the formula C,02. The authors considerthat its formation is represented by the change :CH,(CO,Et), = 2C,H4 + 2H,O + C,O,.The name carbon suboxide is proposed, and the constitution is repre-sented as 0:C:C:C:O.The liquid oxide slowly decomposes at the ordinary temperature,being converted after a time into a dark red solid which dissolves inwater giving an eosin-red solution ; the composition of this product isapproximately the same as that of the original liquid. The decom-position is very rapid at 37" and is instantaneous at looo, and underthese conditions carbon monoxide escapes ; the solid product whichthen remains contains less oxygen and is partly soluble in water, givinga brown solution.Berthelot 2 takes exception to the name carbon suboxide, since thereappear to be a t least three oxides, previously known, to which thename is appropriate.(1) Brodie's oxide, C,O,, obtained by subjectingcarbon monoxide to prolonged electric discharges ; this might beregarded as an anhydride of tartaric acid. (2) Berthelot's oxide,Ber., 1906, 39, 689. Ann. Chim. Phys., 1906, 8, 173102 ANNUAL REPOlI'1'8 ON THE PROGRESS OF CHEMISTRY.C,O,, which is formed by heating Brodie's oxide to 300--4OOO; informula this would correspond t o an anhydride of dihydroxyphthalicacid. (3) An oxide richer in carbon which results from the action ofheat on (2).Berthelot also mentions that in 1891 he gave reasons forsuspecting the existence of a volatile lower oxide of carbon, but thatowing to the inefficiency of the methods of refrigeration known at thattime it was not possible to condense the product.Michael considers that the constitution assigned to this new oxideby Diels and Wolf is improbable, since in parallel cases the changeusually follows an unsymmetric course .when the elimination of wateroccurs with possibility of ring formation, Acetonylacetone, forexample, yields not an acetylene derivative, but dimethylfuran.For this and other reasons he suggests that the compound should beregarded as the lactone of j3-hydroxypropiolic acid, and explains itsformation thus :C*OEt CH2C<C02Et C0,Et -+ -+ c<>o.co coAnhydrides of diethylmalonic acid have been obtained by Einhornand von Diesbach,3 but they prove to be multimolecular. By treatingdiethylmalonyl chloride with a dilute aqueous solution of pyridine, ayellow amorphous powder is obtained which is dissolved by potassiumhydroxide in the cold,:giving the salt of diethylmalonic acid.Ammoniaconverts it into diethylmalonic acid, diethylmalonamide, and diethyl-malonamic acid. Analysis and molecular weight determination by thecryoscopic method (in ethylene dibromide) show the formula to be[C(C,H,),<~~>O] . When this compound is heated in some in-12 -different solvent, such as benzene, it decomposes, giving carbondioxide, diethylacetic anhydride, and a crystalline malonic anhydridewhich behaves towards reagents in the same manner as the originalcompound, but which has the molecular formula (C7Hlo03)4.The methyl ester of dicarboxyaconitic acid,C(CO,Rle),:C(CO,Me)* CH(CO,Me),,which was first isolated by Anschutz in 1903, has been further studiedby this author and Deachauer.3 It is shown that this ester, whenreduced by means of zinc and acetic acid, gives a quantitative yield ofmethyl dicarboxytricarballyate,CH(C02Me)2* CH(C02Me)*CH(C02Me),.The sodium derivative of dicarboxyaconitic methyl ester reacts withmethyl iodide, giving the corresponding methyl derivative ; this, whenAnnalen, 1906, 347, 1.Ber., 1906, 39, 1915.LOC. cit., 1222ORGANIC CHEMISTRY-ALIPHATIC DIVISION.103reduced ascarbsllylich ydrolysedbefore, yields the methyl ester of dicarboxymethyltri-acid, CH(C02Me)2*CH(C02Me)*CMe(C02Me)2, and whenwith sodium hydroxide, methylaconitic acid,C02H* CH: C( C0,H) * CHMe*CO,H.Considerable discussion has taken place with regard to the view putforward by Lewkowitsch in 1900 that the saponification of fats takesplace in stages. Balbiano, for example, in 1902-1903 opposed thishypothesis, and considered the change to be of the type C,H,(OR),+3MOH = C,H,(OH), + 3MR. I n support of this opinion he stated thatif the saponification of glyceryl tribenzoate is interrupted before theaction is complete, the products are only glycerol, benzoic acid, andunaltered tribonzoin, no mono- or di-benzoin being found.Fanto 1expressed a similar opinion, and was unable to detect the presence oflower glycerides; the reaction, that is, appeared practically to bequadrimolecular. Marcusson also 2 comes to similar conclusions, andconsiders that the high acetyl numbers which Lewkowitsch found, andwhich he himself observes only under certain conditions, are to beexplained by the changes experienced by the fatty acids, such asoxydation or anhydride formation. Lewkowitsch, h ~ w e v e r , ~ effectivelyreplies to these criticisms.Kremann has thrown important light upon this question by makingmeasurements of the reaction velocity in the saponification of glyceryltriacetate and glycoldiacetate. According to Balbiano’s view, thefirst-named reaction should be quadrimoleculsr and the secondtermolecular.The values which he obtained, however, were approxi-mately constant when calculated f o r a bimolecular reaction ; if theyare calculated on the assumption that the reaction is ter- or quadri-molecular, the numbers increase as the action proceeds. These resultsappear, therefore, to favour the hypothesis that the change takes placein stages. The rates of saponification of the different acetyl groupsdiffer so little, in the author’s opinion, that the effect is analogous tothe saponification of the ester of a monohydric alcohol by an equivalentquantity of alkali.Abel,4 reasoning from a kinetic standpoint, proposes to explain thefact that the changes mentioned appear to be reactions of the secondorder by assuming that the rates of saponification of glyceryl mono-, di-,and tri-acetates are in the ratio of 3 : 2 : 1, and those of glycol mono-and di-acetates in the ratio 2 : 1.The hydrolysis of esters under the influence of lipase has alreadyMonnlsh., 1904, 25, 919.LOC.eit., 4095.Ber., 1906, 39, 3466.4 Zeit. Elektrochem., 1906, 12, 681 ; and Zeit. physikal, Chem., 1906, 56, 558104 AMNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.been the subject of considerable investigation by Kastle and Loeven-hart, Armstrong, Nicloux, and others. The enzyme undoubtedlydisplays a selective power in promoting by preference the hydrolysisof esters of the higher fatty acids, such as those present in the nrturalfats. The first-named authors (1900) succeeded in effecting the hydro-lysis even of the lowest members, but they concluded that the higherthe molecular weight of the acid, the more readily is its ethyi esterhydrolysed by lipase.Armstrong and Ormsrod 1 have made a furtherinquiry into the nature of the change, with the object of throwinglight on this selective action. Their results lead them to the pro-visional hypothesis that the hydrolysis oE the ester by lipase involvesthe direct association of the enzyme with the carboxyl centre, and thatsuch association may be prevented by the hydration of this centre.Esters, therefore, which are more attractive of water will be lessreadily hydrolysed, and this view is in accordance with the fact thatthe solubilities of ethyl ester3 diminish as the series is ascended.Theinfluence of hydroxyl replacement is well illustrated by the authors’results obtained with the ethyl esters of siiccinic, malic, and tartaricacids, the amounts of hydrolysis after twenty-four hours being in theratio of 20.4 : 15 : 1.8 respectively.Kastle 2 states that the alkyl groups-methyl, ethyl, butyl, isobutyl,allyl, and benzyl-have almost the same effect on the hydrolysis ofester6 by (liver) lipase, but that the presence of acyl groups in thehomologous series has considerable influence. I n the case of methylpropionate the introduction of iodine, in the @position, tends rather toaccelerate than to retard the action, and cyanogen (for example, incyanoacetic ester) has a retarding influence.The hydrolysis of nitric esters of glycerol and of cellulose is alwaysa complicated process, owing to the fact that the nitric acid becomesreduced and the alcohol oxidised.Further studies on this subject havebeen made by Silberrad and and they show that the hydrolysisof ‘ nitrocellulose ’ gives rise to nitric and nitrous acids, ethyl nitrate,ethyl nitrite, alcohol, ammonia, and the following acids : formic, aceticbutyric, dihydroxybutyric, oxalic, tartaric, isosaccharinic, andhydroxypyruvic. Carbohydrates and other compounds are alsoproduced. The abnormality of the hydrolysis both of ‘ nitrocelluloses ’and of ‘ nitroglycerine ’ is also confirmed by the fact that the amount ofalkali consumed on saponification is . much higher than that requiredby theory for the normal change, and further that the velocity ofsaponification, instead of decreasing norm:tllg with the progress of thechange, continues to have about the same value until a large proportionJ Proc, Roy.Soc., 1906, 78, 376. Chem. Cetttr., 1906, i, 1536,Trans,, 1906, 89, 1182 and 1759ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 105of the alkali is used up. Intermediate products are probably formed,and these are gradually acted on by the alkali, so that the saponifica-tion measured during the later stages is not that of the ‘ nitrocellulose ’alone, but is in part a hydrolysis of decomposition products. Nocellulose, or glycerol, is regenerated during these hydrolytic operatioqalthough it can be shown that these substances can resist the action ofnitric acid of the concentration present in the experiments.A moreactive condition of the nitric acid at the moment of its liberation istherefore suggested.I n order to explain the formation of nitrite on the saponification ofnitric esters, Nef (1899) assumed that, in addition to the normal reaction,dissociation takes place in the alkyl group with formation of anethylene and an ethylidene grouping, and that the latter is oxidised t oaldehyde by the nitric acid, nitrous acid resulting. Vignon andMaquenne (1891), on the other hand, assumed the formation of anisomeric nitrate, R-CH(OH)O*NO. Klason and Carlson 1 now con-sider that a more probable explanation is afforded by assuming theperoxide formula for the alkyl nitrate, OR*O*NO; the changes onsaponification might then be represented as OR*O*NO + KOH =KO*O*NO + ROH and OR*O*NO + KOH = KO*NO + OR*OH. Theformation of an alkyl peroxide in this way appears probable from theauthors’ experiments, in which nitric esters were saponified in presenceof phenyl hydrosulphide, in which cases it is shown that a certainamount of phenyl disulphide is formed.Hydrogen dioxide and otherperoxides are known to react with phenyl hydrosulphide with formationof phenyl disulphide, and the authors suggest that the change atpresent under consideration may take place in the following way:RO-O*NO + KOH = RO*OH + KOoNO and RO-OH + BR-SH = ROH +R’,S, + H20. ‘ Nitroglycerine,’ ‘ nitrocellulose,’ and ethyl nitrate,when saponified under these conditions, all gave rise to some phenyl di-aulphide.According to Twitchell,2 sulphophenyl- and sulphonaphthyl-stearicacids may act as catalysts in the hydrolysis of fats, A 1 per cent,solution of the latter acid, for example, effects a nearly completeseparation of the glycerol from a fzit in the course of eight or tenhours.shows that when ‘ nitrocelluloses ’ are boiled with a1 kalis inpresence of hydrogen dioxide, the whole of the nitrogen is obtained asnitrate and nitrite.On acidification the nitrite is oxidised by thehydrogen dioxide to nitrate, and the total nitrogen can then beestimated in this state by the “ nitron ” reagent.BuschBer,, 1906, 39, 2752. J. Amer. Chertb. Soc., 1906, 28, 196,a .Be?-., 1906, 39, 1401106 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.van Romburgh,l by acting on glycerol with excess of anhydrousoxalic acid, obtains a product containing 90 per cent.of triformin;diformin yields a similar result when acted on by anhydrous formicacid. When this product is cooled sufficiently, crystals of triforminseparate. The pure substance crystallises in needles which melt at18'. It is slowly hydrolysed by cold water and more rapidly by warmwater.flitrogen Compounds,Metallic copper, as is well known, is not dissolved by aqueousammonia alone; in presence of oxygen, however, the metal is rapidlyoxidised and dissolved. A t the same time, as shown by Schonbeinand by Tuttle, a considerable portion of the ammonia is oxidised tonitrous acid. Extending this observation to organic bases in place ofammonia, Traube and Schonewald2 have found that ethylamine isoxidised to acetaldehyde and methylamine t o formaldehyde.I n thesecases the copper is converted t o hydroxide, but the ammonia is notoxidised. It is probable that the aldehydes are primarily obtained asaldehyde-ammonias, since the latter do not appear to be acted on byoxygen in presence of metallic copper. When the sodium derivativeof glycine is similarly treated the products are nitrous acid andprobably glyoxylic acid.Burmann 3 describes a convenient method of preparing methylamine.Commercial methyl sulphate is acted on by 10 per cent. aqueousammonia and the mixture is afterwards distilled with 30 per cent.caustic soda ; the ammonia and methylamine are collected in hydro-chloric acid and the resulting hydrochlorides separated by fractionalcrystal lisation.The preparation of acetamide by the usual method of distillingammonium acetate gives a comparatively poor yield, since, according toFrangois,* the initial products are ammonia and ammonium hydrogenacetate, the latter then breaking up into acetamide, water, and aceticacid.By starting with ammonium hydrogen acetate, a yield of 45per cent. of acetamide may be obtained.For the preparation of amides from esters H. Meyer recommendsdigestion of the ester with concentrated aqueous ammonia as the bestmethod, since the action of gaseous or liquefied ammonia may lead tothe formation of mixed products. The action of alcoholic ammoniaon esters is a reversible process, and if excess of alcohol is present theformation of ester may be the principal reaction even at temperaturesbelow 100'.1 Proc.K. Akad. Wetensch. Amsterdam, 1906, 9, 109.4 J. Pharm. Chim., 1906, [vi], 23, 230.Ber., 1906, 39, 178. Bull SOC. chim., 1906, [iii], 35, 801.Monatsh., 1906, 27, 31ORGANIC CHERIISTRY-ALIPHBTIC DIVISION. 10'7The methyl esters are much more quickly and completely convertedinto amides by the action of aqueous ammonia than the higherhomologues. On the other hand, the change takes place more readilyas the acidic radicle is stronger ; trichloroacetic ester, for example,readily givas the amide in this way, whereas trimethylacetic esterdoes not.Attention was called in the previous Report (1905, 75) to the form-ation, by Windaus and Knoop, of methylglyoxaline, or methyliminazole,CH3'8g$WH, from dextrose by the action of ammonia in presenceof zinc hydroxide.It was assumed that glyceraldehyde is first formedand that this then passes into methylglyoxal, which in its turn isacted on by ammonia and formaldehyde to give methylglyoxaline.This view is favoured by the fact that a better yield is obtained iEformaldehyde is added to the dextrose and zinc hydroxide-ammonia.Since methylglyoxaline occurs in some natural alkaloids it is evident thatthe synthesis here described may have an important bearing in plantphysio1ogy.l Windaus has now extended these observations by thesubstitution of acetaldehyde for formaldehyde i n the above-mentionedsynthesis and has in this way obtained 1 : 4-dimetbyliminazole.Thechange is probably represented as follows :>C*CH, + 3H,O. CH,-$*NHCHON NH3 + OCEPCH, =CH,*YOCHO NH,I n absence of acetaldehyde only the mono-methyl base is produced ;this appears to indicate that under the conditions here employedacetaldehyde is not formed by the action of hydroxyl ions on dextrosein presence of ammonia.3I n order t o establish the constitution of this base advantage wastaken of Wallach's observation that the substitued iminazoles inwhich the replacing radicle is attached to nitrogen are transformed,when led through a red-hot tube, into the l-substituted compounds.Thus 5-methylglyoxaline yields the l-methyl compound under theseconditions. Now the 1 : 4(or 5)-dimethylglyoxaline has alreadybeen obtained by Jowett and Potter.* By passing this through astrongly heated glass tube and purifying the resulting compound bymeans of its silver salt, the author obtained a product identical inevery way with the 1 : 4-dimethyliminazole prepared from dextroseand acetaldehyde.The preparation and synthesis of amino-acids is still receiving con-siderable attention owing to the importance of these compounds from aCompare Meldola, Trans., 1906, 89, 764.Compare Schade, p.91, this volume.Bar., 1906, 39, 3886.Trans., 1903, 8108 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.biological standpoint. A complete summary of this subject, bringingthe results up t o the end of last year, will be found in an addressgiven by Fischer to the German Chemical Society.1Of all the known general methods of preparing amino-acids, thesimplest appears to consist in the treatment of the a-halogen fatty acidwith ammonia.For the purpose of obtaining these halogen derivatives,Fischer and Schmitz2 recommend the bromination of t h e alkylinalonic acids. This method gives a yield of the bromomalonic acidderivative, which is almost qiiantitative, and the latter on heatingreadily breaks up into the required bromo-fatty acid and carbon dioxide,especially under diminished pressure. I n this way the authors prepareda-bromoisohexoic acid from isobutylmalonic acid and y-phenyl-a-bromo-butyric acid from y-phenylethylmalonic acid.The preparation of amino-acids, through the amino-nitriles, fromaldehydes or ketones, may be carried out, as first pointed out byLjiibavin in 1882, by the direct action of ammonium cyanide instead ofby the successive treatment with ammonia and hydrogen cyanide ; inthis way Gulewitsch (1900) obtained a large yield of a-aminoisobutyricacid from acetone.The same author and Wasmus 3 make a furtherstudy of the most favourable conditions and show that the reaction isof general application for all ketones of the series :The method has the advantage that iminonitriles and oxynitriles arenot produced. Whereas the aminonitriles hitherto described areunstable oils which cannot be distilled, many of those obtained bythe present authors could be distilled unchanged, under reducedpressure, and were stable when kept.Zelinsky and Stadnikoff,4 for this preparation, prefer to act on thealdehyde or ketone with potassium cyanide and ammonium chloride, inequal molecular proportion, in aqueous or aqueous -alcoholic solution.They represent the change as taking place in the following way :(1) KCN + H20 Z KOH + HCN, (2) R*CHO -t HCN = R*CH(OK).CN,(3) NH4C1 + KOH = KCl + H,O + NH,, and (4) R.CH(OH).CN +NH, = R*cH(NH,).CN + H20.For the preparation of amino-acids, the resulting aminonitriles arehydrolysed by means of hydrochloric acid.Paal and Weidenkaff 5 have continued their investigations, whichwere referred to in the previous Report (p.69), on the behaviour ofGrignard's reagent towards amino-acids ; the investigation was under-taken with the object of obtaining products which might serve for thecharacterisation of these acids, glycine being first studied. TheCnH,,, 1'CO*CnH,n+ 1.1 Bcr,, 1906, 39, 552.2, LOG. cit., 351. 3 LOG. cit., 1181.LOC. cit., 1722. LOC. ciL, 810ORGAN 1 C C HEM ISTRY - ALI PH ATIC DIVISIOK. 109authors now show that the ethyl ester of diethylaminoacetic acid withmagnesium ethyl iodide gives rise to diethylaminomethyldiethyl-carbinol, OH*C(C2H5),*CH2*N(C2H5)2. This compound, like the productpreviously described, dissolves easily in Trganic solvents, but issparingly soluble in water.is similarly obtained from ethyldiethylaminoacetate and magnesiumphenyl bromide.Extending these observations to aminodicarboxylic acids, the sameauthors 1 find that the ethyl ester of inactive aspartic acid reacts withmagnesium phenyl bromide to give r-/3-amino-aa66-tetraphenyl-butane-as-diol :C02Et*CH(NH,)*CH2*C02Et --+0H*C(C6H5)2*CH(NH2)*CH,*C(C,H,)2*OH.It is a crystalline substance and is very sparingly soluble in water, butdissolves easily in alcohol, ether, benzene, &c.Siegfried, in 1905, found that on mixing solutions of glycine andbarium hydroxide in equivalent quantities and passing carbon dioxideinto the mixture, no precipitation of barium carbonate takes place andthe clear solution only begins to cloud after standing for some time.Other amino-acids, such as alanine, leucine, aspartic acid, andglutaminic acid, behave in a similar way, and it is shown that thesolutions obtained contain salts of corresponding substituted carbamicacids, CO,H*R'*N H*C02H.Glycine, for example, forms '( carbamino-CH2*NH*7Oacetic acid," the calcium salt of which has the formula I CO-OCa-0It would appear that other amphoteric substances, such as peptonesand albumoses, can, in presence of bases, form loose compounds withcarbon dioxide which are probably of analogous constitution. Even inabsence of bases these amino-compounds are capable, to a certainextent, of fixing carbon dioxide.Leuchs2 has now prepared the anhydride, and salts, of carbamino-acetic acid (glycinecarboxylic acid) in an entirely different manner, asfollows : carbethoxyglycine is readily converted into its correspondingacid chloride by means of thionyl chloride; on warming this acidchloride for some time a t 80" ethyl chloride splits off, leaving theThe corresponding compound,OH*C(C,H,)2'CH2*N(C2H,)27anhydride, TH-">O.A better yield is obtained if the carbo- CH,*COmethoxyglycyl chloride is employed. This anhydride dissolves, givingan acid solution in ice-cold water, but at about 15' carbon dioxide isevolved and pure glycine is left in solution. If the ice-cold aqueoussolution of the anhydride is mixed with the calculated quantity ofBer., 1906, 39, 4344. LOG. cit., 857110 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.baryta-water, a crystalline barium salt is obtained which is found tobe identical with the product prepared by Siegfried’s method abovementioned.When the anhydride is rubbed with twice its weight of water a t theordinary temperature it evolves carbon dioxide and is converted into awhite, nearly insoluble powder, which appears to be a glycine anhydride(C2H30N),.This product differs from diketopiperazine and isprobably identical with the substance previously obtained by Balbianoand Trasciatti in 1900 by heating glycine with glycerol, and by Curtiusfrom the ‘‘ biuret base.”has extended this observation to a study of thebehaviour of malonic ester chloride under similar treatment. Whenthis compound was heated a t 125-130’for an hour, hydrogen chloridewas evolved, but ethyl chloride was not produced ; on continuing thereaction, a brownish, horny substance separated, which, after purificationby ether, yielded a citron-yellow, crystalline compound having theformula C,,H,,O,.The author considers that the change which takesplace consists in the condensation of three molecules of the ester-chloride, with elimination of hydrogen chloride, to phloroglucinol-tricarboxylic ester, and this, by loss of alcohol, yields the compound inquestion, which may beThe same authorO-O--ICO,Et/\CO or CO,Et/\CO,EtOH1 (OH \/ OH1 (OHC0,Et co-- \/The synthesis of serine was accomplished in 1902 in two differentways by Fischer and Leuchs and by Erlenmeyer, jun., respectively.The first-named authors treated glycollaldehyde, prepared fromdihydroxymaleic acid, with hydrogen cyanide and ammonia, andobtained in this way the nitrile of a-amino-P-hydroxypropionic acid ;this on hydrolysis gave the corresponding acid, or serine.Erlen-meyer’s method consisted in the condensation of the esters of hippuricand formic acids to hydroxymethylenehippuric ester ; this on reduc-tion gives rise to benzoylserine, which yields ssrine on saponification.Neither of these methods serves well as a method of preparing thesubstance, and an advantageous new synthesis has now been effectedby Leuchs and Geiger 3 in which the starting point is commercial chloro-acetal. By action of sodium ethoxide on chloroacetal at 12O-l6O0,ethoxyacetal, CH,(OC,H,)*CH(OC,H,),, is obtained, and this byheating with dilute acids yields ethoxyacetaldehyde, CH,(OC,H,)* CHO.Coinpare Ann. Ryort, 1904, 77. * Zoc. cit., 2641.a Ber., 1906, 39, 2644ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 111The crude product so obtained is then treated with ammonia and withhydrogen cyanide, in which way the aminonitrile,CH,(C)C,H,)*CH(NH2)'CN,is produced, and this by action of concentrated hydrochloric acid yieldsthe corresponding acid, namely, P-ethoxy-a-alanine,C H, ( 0C2E5) CH (N H,) C0,H.For the object in view, i t is unnecessary to isolate this product, andthe reaction mixture, after separation of ammonium chloride andevaporation, is now acted on with concentrated hydrobromic acid toreplace the ethoxy-group by hydroxyl :CH,(OC,H,) CH(NH,) CO,H + HBr =CH,(OH)*CH(NH,)*CO,H + C,H,Br.The yield of serine obtained in this way is about 40 per cent.of thatrequired by theory from the ethoxyacetal employed.Although serine has hitherto been obtained only in the racemicform, there is reason to believe that, like other amino-acids, itexists in protein substances in the optically active form, and thatracemisation takes place on hydrolysis.It becomes, therefore, a matterof interest to attempt the resolution of ordinary racemic serine, andthis has now been successfully accomplished by Fischer and Jacobs.'For the purpose of resolving racernic leucine, Fischer, in 1899,prepared the benzoyl derivative and combined this with ciichonine,but later it has been found by this author and Warburg2 that a moresuitable method consists in obtaining the formyl derivative andseparating this into its components as brucine salt. Neither of thesemethods appeared to be successful in the case of serine, but it wasfound that the resolution can easily be effected by forming the p-nitro-benzoyl compound and converting this into quinine and brucine salts,The amino-acid was first acted on by p-nitrobenzoyl chloride in presenceof potassium hydroxide, and the resulting crystalline, sparingly soluble21-nitrobenzoyl d-E-compound was heated with quinine in alcoholic solu-tion, when, on cooling, the d-quinine salt separated out in colourlessneedles. Hydrolysis of this salt with sodium hydroxide yielded thefree d-nitrobenzoyl derivative, from which d-serine was obtained bydecomposition with hydrobromic acid. It is a crystalline dextro-rotatory substance, and is more easily soluble than the racemic serine.The quinine salt of p-nitrobenzoyl-Z-serine which remains in themother liquor after the above separation can be obtained on evapora-tion; it is not pure, however, and still contains about 10 per cent. ofthe dl-compound. For further purification it is converted into thebrucine salt and separated as before. By converting Z-serine intoits methyl ester and allowing this to stand for some hours at 25', theBey., 1906, 39, 2942. LOC. c i t . , 1905, 38, 3997112 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRP.anhydride, C,H,,O,N,, is obtained. This product is a crystalline,strongly lsvorotatory substance, and appears to be identical with asubstance which the author has obtained by the hydrolytic decom-position of silk fibroin. From t h i s observation i t would appearprobable that natural serine is the I-compound.F. Ehrlichl states that racemic amino-acids are readily attacked byyeast in solutions containing a relatively large proportion of sugar,and that good yields of Z-alanine, d-leucine, and I-a-aminoisovalericacid were prepared in this way from the corresponding racemic com-pounds. The yeast appears t o attack both optical isomerides, but, ingeneral, one is attacked more rapidly Shan the other.Polypeptides.The refiearches of Fischer and his colleagues on the chemistry of thepolypeptides continue to make a rapid advance. A useful summaryof the subject, which includes the results obtained up to the end of1905, will be found in Fischer’s lecture to the German ChemicalSociety on amino-acids, polypeptides, and proteins, to which referencehas already been made. Since that time a large number of highlyimportant results have been obtained, but, in the limited space hereavailable, it would serve no useful purpose to attempt any abstract ofthis highly detailed and descriptive work2As an example of the progress which has been made in the synthesisof peptides containing long chains of amino-acid residues, it may bementioned, in passing, that Fischer has succeeded in building up adodecapeptide, containing one leucine and eleven glycine residues.By acting on bromoisohexoyldiglycylglycyl chloride,C,Hg*CHBr* CO(NH* CH2* CO);NH*CH2~COCl,with diglycylglycine, NH,*CH2*CO-[NH-CH2*CO]*NH*CH2*C02H, andtreating the resulting bromo-compound with ammonia, the hepta-peptide leucylpen tagly cy lglycine,C,H,*CH( NH2)*CO(NE*CH,eCO),*NH*CH2-C02H,was obtained. If a similar series of operations is performed with thesubstitution of triglycylglycine for diglycy lglycine, the result is anoctapeptide ; or, if pentaglycylglycine is employed, a decapeptide.Finally, by proceeding in a similar way with bromoisohexoyltetra-glycylglycine chloride and pentaglycylglycine, the dodecapeptide,leucy ldecaglycylglycine,C,H,* CH( NH,)*(NH*CH,* CO),,*NH*CH,*CO,H,was prepared.nearly colourless mass, and ha8 no definite melting point.I n the dry state i t has the appearance of a loose,I n alkaline%%it. Yer. deut. Zuciccrind, 1906, 840. ’ Ih., 1905, 38, 4173 ; 1906, 39, 453, 530, 752, 2315, 2893, 3981ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 113solution it gives a strong biuret reaction, and its solution in diluteaqueous ammonia is precipitated by a saturated solution of ammoniumsulphate; in most of its properties, in fact, it shows a close resem-blance to the natural proteins.A considerable number of polypeptides containing optically activeamino-acid residues have been synthesised and studied ; amongst these,I-leucylglycine, which was obtained from d-a-hromoisohexoylglycineC,H,*CH*KH*$!O which isand ammonia,’ yields the anhydrideproved to be identical with a product which Fiscber and Abderhaldenobtained from elastin by hydrolysis with sulphuric acid.2~‘o-NH- CH;H. J. H. FENTON.1 Compare Walden, Ber., 1897, 30, 3146. Loe. eit., 2318.VOL. 111.