ATTEMPTED RESOLUTION OF IlACEMIC ALDEHYDES. 405XLV.-Atlemptecl Resolution of Racemic Aldehydes.By WILLIAN ORD WOOTTON.DURING recent years numerous investigations have been under-taken with a view to elucidating t,he relationship between thechemical composition and rotatory power of optically active sub-stances. Although considerable progress has been made in thisdirection by the study of homologous series of ethereal salts andalkyloxides, it can scarcely be claimed that any generalisations ofwide application have yet been established. This is no doubt to beexplained partly by the uncertainty attaching to the conventionalmethod of expressing optical rotatory power, and partly by thefact that with few exceptions the compounds chosen for examinationhave been of too complex a character to admit of great emphasisbeing laid on the conclusions drawn from them.Owing chiefly toE E 406 WOO‘rTON : ATTEMPTED RESOLUTION OFthe difficulty in preparing them, we are acquainted with bat fewstructurally simple substances which could be utilised in such work.The ideal substance from this point of view would be an easilyaccessible compound, of low molecular weight, having only oneasymmetric carbon atom, and containing no cyclic grouping; itwould be an additional advantage if it contained a chemicallyreactive group or radicle directly attached to tlie asymmetric carbonatom, through the agency of which the effect of substitution,addition, or of the introduction of double linkings could be studied.The value of a substance containing a single asymmetric carbonatom in connexion with the application of Guye’s modified equationhas been pointed out by Bose (Physikal. Zeitsch., 1908, 9, 860).The series of aldehydes of the type CHRR’*CHO fulfils theforegoing conditions, and since they are easily obtained by thegeneral method of Darzens (Corn@.rend., 1904, 139, 1214), itappeared to be of interest to ascertain whether these presumablyracemic substances are capable of resolution into optical antipodes,or whether by other processes they could be obtained in activeforms. The direct resolution of racemic aldehydes has been accom-plished by Neuberg and Federer (Bey., 1905, 38, 868), whoemployed d-phenylamylhydrazine, a substance not easy to prepaxein the pure state, and which, like most amyl compounds, might beexpected to form oily derivatives. I n a previous communication(Trans., 1907, 91, 1890) I have described the preparation of anoptically active amine, namely, 4-bromo-3-aminophenyl-a-camphor-amic acid, which it was hoped might be applied to the same purpose.The action of this base on hydratropaldehyde, CI’IMePh-CHO, hasnow been examined, but the results obtained did not seem towarrant the extension of its use.Attention has been drawn (Zoc.cit.) to the di%culty with whichcamphoric anhydride unites with the nitroanilines t o form thenitrophenyl-a-camphoramic acids. This combination has now beeneffected in the case of m-nitroaniline. The nitro-acid obtained hasbeen reduced to the amino-compound, and the beliaviour of theproduct towards a racemic aldehyde studied.For this purposebutylchloral, CCl,Me*CIICl*CHO, was selected, since Wheeler ( J .Amer. Chem. SOC., 1908, 30, 136) has found that chloral readilycondenses with primary aromatic amines, forming well-definedcompounds. I n the present instance, however, although con-densation between one molecule of tlie aldehyde and two moleculesof the base presented no difficulty, it was not found possible toresolve the product by fractional crystallisation into its opticallyactive components.A more promising method that suggests itself would be to resolvRACEMIC ALDEHYDES. 407a PP-substituted glycidic acid by the aid of an alkaloid, and then tod.ecompose the active salts by a mineral acid, when carbon dioxideis eliminated and the aldehyde produced.Experiments have beencarried out in this direction, but although a sodium salt of/3-phenyl-/3-metliylglj cidic acid has been obtained having [a], + 1 6 * 6 Oin aqueous solution, yet the corresponding aldehyde appears to beoptically inactive. This, however, may be due t o the fact thatthe acid itself contains two asymmetric carbon atoms, and it ispossible that resolution has only been effected in the case of thecarbon atom which ceases t o be asymmetric on conversion of thescid into the aldehyde:CMePh<b cH'Co2H -+ CHMePhCHO.I n the expectation of obtaining optically active bases by thereduction of nitro-derivatives of benzylidenecamphor, I haveexamined the action of 0-, m-, and p-nitrobenzaldehyde on sodiumcamphor.Albhough this line of inquiry has been abandoned onaccount of the very poor yields obtained, the results of the experi-ments are recorded in the sequel.A point of some interest has been noticed in connexion with theoptical properties of the derivatives of a-camphoramic acid. Ithas usually been found that the rotatory power of a cyclic com-pound is considerably greater than that of the correspondingopen-chain derivative. Thus the rotatory powers of esters of1-methyl-3-cycZopentanone-4-carboxylic acid are about thirty timesas great as those of the corresponding esters of methyladipic acid(Haller, Com.pt. rend., 1905, 140, 1205). The hexahydrophthalicacids have much lower specific rotations than their anhydrides(Werner, Ber., 1899, 32, 3046).Many other instances might bequoted. Camphoric acid and its anhydride, however, form anexception to the rule, the acid ha.ving [a], +46O in alcohol, whilstthe anhydride has [aJD - 7.7O. Similarly, a-camphoramic a,cid has[a], + 45O in acetone, whilst camphorimide has [a],, - 10.1O. I norder to ascertain whether this peculiarity was exhibited by theN-substituted amides and imides of camphoric acid, I have preparedseveral new members of this series, and determined their rotatorypower in acetone solution a t a temperature between 19O and 21O.Variations in the concentration of the solution between 1.5 and3 parts per 100 have very little effect on the rotatory power.The results arc3 summarised OK p.408.It will be noticed that the molecular rotatory power of the acidis always greater than that of its corresponding irnicle, except inthe case of the a-naphthyl aiid o-broniophenyl derivatives. Thedifference between the molecular rotatory powers of the acid an408 WOOTTOK : ATTEMPTED RESOLUTION OFDerivative.Me thy1 ........................Ethyl ...........................n-Propyl .....................n-Butyl ........................n-Amy1 ........................n-Hexyl .......................Ally1 ...........................O-Tolyl ........................P-Tolyl ........................B-Naphthyl ..................m-'l'olyl ........................a-Naphthyl .................4-Hydroxyphengl .........4 -E thoxy phenyl ............2-Chlorophenyl ............3-Chlorophenyl ............2-Bromophenyl ............3-Bromophenyl ............4-Bromophen yl ............3-Nitrophenyl ...............3-Aminophenyl ............4-Broino-3-nitrophenyl ...4-Bromo-3-aminophenyl ..4-Benzeneazophenyl ......4-Chlorophen yl ............*Camphoramic acid.-33.24" 70 *6O17-1 38.818.45 44-515-8 40 -318.9 50.816 -9 47 '813 *54 32.433 '9 98.031 '0 89'037.0 107 -07-46 24'264 '9 210.949'2 143'139.5 130.037.0 114'040-5 125-533-2 117-037.8 134'032.0 102.439.9 116.540'7 109.5 *87.7 332.5 *[alD'- 16.4 - 50'8- 31'8 - 41'8- 48'4 - 193'2 +tIn alcoholic solution.Camphorimide. - 7 '26" 14.1'8.87 18 510.9 24.312'8 30.37.7 19.310.8 28.67 -95 17'615.7 43.017.6 47 -012.7 34.026'34 so-718.0 55.218.5 55'014.1 41 *216'2 47 .o16'2 47'013 -3 44.715.4 51'015.7 52.01.7 5-1ra3D.[MID.- -.- -- - - (feeblydextrorotatory)- -imide in the case of 0-, m, and p-isomerides is always greatest inthe p-compounds. The homologous series of alkyl derivatives showno marked regularity; it is noteworthy, however, that the twoally1 compounds show distinctly lower rotatory power than thecorresponding n-propyl derivatives, in this respect resembling theallylamides in the rnalic and tartaric series, which show abnormallylow rotatory powers when compared with the propylainides (Frank-land and Done, Trans., 1906, 89, 1861).EXPERIMENTAL.Attempted Preparation of OpticaZZy Active Bydratropaldehyde.Hydratropaldehyde and 4-bromo-3-amino-a-camphoramic acid didnot interact in alcoholic solution, either in the cold or on warming,and attempts to obtain a condensation product with benzaldehydewere equally unsuccessful.Resolution of Sodium 8-Phenyl-8-methylglycidate.Preliminary experiments with the quinine salt of P-phenyl-P-methylglycidic acid having shown that this substance was unsuit-able for the purpose, the brucine salt was prepared by addinRACEMIC ALDEHYDES.409brucine hydrochloride (I mol.), dissolved in the minimum amountof warm water, to a warm aqueous solution of sodium P-phenyl-P-methylglycidate (2 mols.). On allowing the solution to evaporatespontaneously over potassium hydroxide in a vacuum, clusters ofradiating, irregular prisms separated, which were crystallisedrepeatedly froin absolute alcohol until optically constant, care beingta.ken to avoid prolonged heating with the solvent :0.2402 gave 10.4 C.C.N, at 23O and 760 mm.0.6475, in 20 C.C. water, gave, in a 2-dcm. tube, a - 1-14', whence0.6800, in 20 C.C. absolute alcohol, gave, in a 2-dcm. tube,a -0*60°, wlience [aID - 8'82O.When rapidly heated, the salt melts and decomposes a t141-142O. It decomposes on boiling with water or when heateda few degrees above its melting point, giving brucine and hydratrop-aldehyde. A good yield of the latter was obtained when the saltwas slowly heated under diminished pressure; the product wascollected in three separate fractions, but each of these proved tobe optically inactive when examined in ethereal or alcoholic solution.The mother liquor remaining from the preparation of the salt waspale brown in colour, and when kept in a vacuum deposited a smallquantity of the crystalline brucine salt, together with a resinoussubstance which appeared to contain hydratropaldehyde togetherwith the free alkaloid. Dilution of the liquid with water caused afurther precipitation of brucine. The hydratropaldehyde was foundt o be inactive.N=4.89.C,,H,,0,N2 requires N = 4.89 per cent.[a],, -17.7'.QH*CO,Na, w ~ s Sodium d-P-Ph eny 1-P-me t h y lgl y cidat e , CH3> "<oCGH.5obtained by grinding the foregoing brucine- salt with water con-taining the calculated amount of sodium hydroxide. The alkaloidwas removed by repeated extraction with chloroform, and thesolution allowed t o evaporate in a vacuum.The sodium salt wasfinally obtained in colourless leaflets after three crystallisationsfrom dilute alcohol :0'3002 gave 0.1097 Na,SO,.0.6000, in 20 C.C. water, gave, in a 2-dcm. tube, a + l*OOo, whenceNa= 11-88.C,H,O,Na requires Na= 12-10 per cent.[a],, +16*6O.When dissolved in water and treated with slightly less than thecalculated amount of sulphuric acid, carbon dioxide was evolved,and the solution became turbid through the separation of hydratrop-aldehyde. I n one experiment this was removed by steam dis41 0 WOOT1'ON : ATTEMPTED RESOLUTION OFtillation, and in another by extraction with ether; both specimens,however, appeared to be optically inactive when examined in 5 percent.solutions of alcohol, chloroform, or ether. The aldehyde,moreover, gave a semicarbazone identical with that obtained fromthe racemic sodium salt.Attempted Resolution of B~t?/Zc?tloraZ.-Condensation occursreadily when an aqueous solution of m-aminophenyl-a-camphoramicacid (see below) is shaken with butylchlornl. It is advisable? how-ever, t o add the butylchloral (1 mol.) to a solution of the sodiumsalt of the acid (2 mols.). The aldehyde dissolves immediatelywith considerable development of heat.Tric h lor0 b u t ylidene b is-3-aminoph emyl-a-camphorumic A cid,CMeCI,*CHC1*GH(NH*C6H4*NH*CO*C8H14~C0,H)2,separates as it bulky mass of colourless needles when the solutionof its sodium salt is acidified with acetic acid.After crystallisationfrom dilute alcohol, it melts and decomposes at 126-130° whenheated moderately rapidly. Attempts to resolve it by fractionalcrystallisation from this solvent and also from acetone were notsuccessful, successive fractions showing practically the same rotatorypower. Prolonged heating with solvents brings about decom-position :0.9081 gave 0.0510 AgC1.0.5110, in 20 C.C. acetone, gave, in a 2-dcm. tube, aD +1*40°,C1= 13.89.CssH4,0,N4C1, requires C1= 14.38 per cent.whence [aID +27*4O.Ni't ro-derivativ es of Benz ylid enecamphor.The only nitro-derivative of benzylidenecamphor hitherto knownhas been described by Haller (Compt. rend., 1895, 121, 36). Bythe action of fuming nitric acid on benzylidenecamphor, a colour-less compound wits obtained, to which he ascribed the constitution:C(NO,)* CHPh-NO,C*H,4<&-jThe nitro-groups do not appear to be attached to the benzenenucleus, since the substance furnishes benzylidenecamphor onreduction.Action of p-Nitrob enzaldehyde o n Sodium Camphor.-Thesodium camphor required in these experiments was prepared by theaction of sodium or finely divided sodamide on camphor dissolvedin dry ether, benzene, or toluene.The reactions appeared t o followthe same course whichever method was adopted, the use of sodamidewith ether, however, wits preferred as giving cleaner products anRACEMIC ALDEHYDES. 411a better yield. On adding two-thirds of the calculated quantity ofp-nitrobenzaldehyde to a well-cooled suspension of sodium camphor,a, vigorous action ensued, accompanied by development of heat.The mixture was kept below 5O for an hour, and then heated fora short time on the water-bath.The reddish-brown, pasty masswas extracted with water, the layer of organic solvent separated,dried, and finally heated on the water-bath until the solvent andthe greater 1 art of unaltered camphor had been removed. Theaqueous extract on the addition of an acid gave a voluminous yellowprecipitate consisting chiefly of p-nitrobenzoic acid. The residueleft after evaporation of the organic solvent appeared as a viscous,red oil, which slowly deposited yellow crystals. The oily matter wasremoved by extraction with cold alcohol and examined separately.The crystalline residue contained the following two substances.I.A compound, C,,H,~O,N,.-This product is sparingly solublein alcohol, ether, or benzene, and readily so in pyridine or carbontetrachloride, from which it separates in small, orange-red prisms,melting at 280-281O. The compound is distinguished by itsremarkably high rotatory power; it does not give Liebermann’sreaction, and develops no coloration with alcoholic potash. Twodeterminations of the moleculax weight in chloroform solution bythe ebullioscopic method gave 422 and 446 respectively, the aboveformula requiring 538 :0.0913 gave 0.2529 CO, and 0.0597 H,O.0.3559 ,, 12.8 C.C. N, at 18O and 744 mm. N=5*65.0.0939, in 25 C.C. chloroform, gave, in a 2-dcm.tube, a, +4.55O,II.--4--Nitrobenzylidenecamp/~or, c,H,,<X~ .-Thiscompound separates from alcohol in bright yellow, glistening leaflets,melting a t 156-157O; it is sparingly soluble in alcoholic potassiumhydroxide, giving a yellow solution. Concentrated sulphuric aciddevelops an orange-red coloration :C = 75-52 ; H = 7.25.C,,H,O,N, requires C = 75.82; H = 7-06 ; N = 5.20 per cent.whence [a], + 605O, and [MI, + 3255O.:CH*CGH,*NO,0.1012 gave 0.3148 CO, and 0.0592 H,O.0.1780 ,, 7.6 C.C. N, at 16O and 754 mm. N=4.82.0.3102, in 20 C.C. chloroform, gave, in a 2-dcm. tube, a, +3-55O,whence [a], + 437’, and [MI, +1345O.Examination of t h e Alcoholic Extract.-A deep red oil, havinga slight odour of camphor, remained after removal of the alcoholby evaporation.The oil is insoluble in water, but freely soluble inthe usual organic media; on adding alkali hydroxide to its alcoholicsolut.ion, an intense purple coloration is developed, which, onC = 71.71 ; H = 6-38.CI7Hl9O3N requires C = 71.59 ; H = 6-66 ; N = 4-88 per cent412 WOOTTON : ATTEMPTED RESOLUTION OFdilution with water, changes to red.acids, but restored by alkalis.contains an enolic form of 4-nitrobenzylidenecamphor :The colour is destroyed byIt is possible that this productc:c:c,H', : y oC,H,,<&O OH'A chromophoric oil having similar properties has been describedby Forster, who obtained it by the action of p-nitrobenzyl chlorideon isonitrosocamphor in presence of sodium ethoxide (Trans., 1908,93, 249).Decomposition occurs when the oil is distilled underdiminished pressure, and all attempts to isolate a pure compoundor prepare a crystalline derivative have failed.No chromophoric substance is formed if the temperataure ofreaction is allowed to rise during the preparation; under theseconditions, the main product is the compound C3,H3d0,N2, togetherwith a very insoluble brown substance which has not yet beenobtained in a state of purity. To ascertain whether the presenceof the camphor nucleus is essential for its formation, experimentshave been carried out on the action of p-nitrobenzaldehyde on thesodium derivatives of ethyl acetoacetate, carvone, and pulegone ;no chromophoric product was recognised, however, and this wouldappear to exclude the possibility of the colour having arisen fromthe action of the alkali on any derivative of dinitrostilbene.Itmay be mentioned that the sodium derivative of pulegone is veryreadily prepared by the action of sodamide on an ethereal solutionof pulegone. The action proceeds briskly without warming, and agood yield is obtained.Action of 0- and m-Nitrobenzaldehyde orb Sodizcm Camphor.2-1Vitrobenzylidenecamphor, C17H1903N, prepared in the same wayas the 4-nitro-compound, occurs as well-formed, light brown prisms,melting at 116-117O. A solution in chloroform gave [a], +50°approximately; owing t o the absorption of light, the rotatory powercould not be accurately determined. The compound itself gives nocoloration with alcoholic potassium hydroxide, but the oily materialfrom which it is separated develops an intense purple colorationwith this reagent:0.2633 gave 11.9 C.C.N, at 28O and 766 mm.C,,Hlg03N requires N = 4.88 per cent.S-flitrob enzylidenecamphor, C,,Hl9O3N.-This compound andm-nitrobenzoic acid are the only products of the action of maitro-benzaldehyde on sodium camphor. It was obtained as a yellowoil, which, on addition of alcohol, rapidly solidified. WhenN=4.99RACEMIC ALDEHYDES. 41 3crystallised from hot alcohol, it forms very pale yellow needles,melting a t 110-11lo :0.2024 gave 9.4 C.C. N, a t 19O and 748 mm.0.0934, in 15 C.C. chloroform, gave, in a 2-dcm. tube, a, +3*92O,N=5*13.CI7Hl9O3N requires N = 4.88 per cent.whence [a]= +31l0, and [MI, +783O.Alkyl Derivatives of a-Camplaoramic A cid, CO,H*C~H,,*CO*NHR.The following new members of the series were prepared by theinteraction of camphoric anhydride (1 mol.) with an alcoholicsolution of the amine (2 mols.).After purification by conversioninto the sodium salt, the free acid was regenerated by the additionof hydrochloric acid and crystallised from dilute acetone :Analysis.EmpiricalEthyl . . . . . . . . . Cl,H,,03Nn-Propyl.. . . . C,3H,303NDerivative. formula.n-Btttyl . . , . . . C,,H,,O,Nn-Amy1 . . . . . . C,,H,O,Nn-Hexyl . . , , . . C,,H,,O,NAlly1 ......... C,,H,,O,NCrystallineform.HexagonalleafletsHexagonalleafletsHexagonalleafletsCrystallinemassHexagonalleafletsLeafletsM. p. Found.173-175" Nz6.08187-188 N = 5-79124-125 C = 65 *71H= 9-48- C =66*58H = 10.25123-124 N= 5.21157-158 N=5.66Theory,per cent.6.175.8165.899 '8066-9110.034.955 *S7Aryl Derivatives of a-Camphoramic A cid,CO*NHRC*H,*<C~,HI n most cases these compounds are readily obtained by heatingan intimate mixture of camphoric anhydride and the substitutedamine for a few minutes at 150-180°.I n the case of m-nitro-aniline, a-naphthylamine, and ortho-substituted amines, it is neces-sary to heat for a longer period in sealed tubes.3-Nit rophenyl-a-canzlrhoramic A cid,CO,H * C,H ,* CO NH C,H,* NO,,is prepared by heating 13 grams of camphoric anhydride with10 grams of m-nitroaniline at 150° for one hour in a sealed tube.The crystalline mass is dissolved in dilute ammonia, the solutionfiltered after twenty-four hours, and then acidified.The first fewdrops of acid precipitate a brown, resinous product, but furtheraddition of acid yields the required compound in a state of purity.It is crystallised from acetic acid containing a little stannouschloride, and finally from alcohol, from which it separates in large414 WOOTTON : ATTEMPTED RESOLUTION OFcolourless, hexagonal leaflets, which darken at about 200°, and meltand decompose at 212-213O :0.3052 gave 18.6 C.C. N, at 20° and 754 mm. N=8.71.0.6178, in 20 C.C. acetone, gave, in a 2-dcm. tube, a, +1*97O,3-A minophenyl-a-camphoranzic A cid,C,,H,,O,N, requires N = 8.75 per cent.whence [a] +32*Oo.CO,H*C,H,,*CO*NH*C,H,*NH,,prepared from the foregoing compound by reduction with ferroussulphate in ammoniacal solution, forms small, colourless needles,melting at 196-197O :0-2000 gave 16.6 C.C.N, a t 21° and 766 mm.0-3908, in 20 C.C. acetone, gave, in a 2-dcm. tube, a,, +1-56O,whence [a], +39.9O.The acetyl derivative crystallises in silky needles, melting a t220-221O. The hydrochloride of the base is easily soluble in water,and on diazotisation yields a clear solution which, on the additionof alkaline &naphthol, furnishes a bright red azo-compound. Asolution of the base in dilute alcohol gives an immediate precipitateon the addition of an aldehyde; this arises from condensation oftwo molecules of the base with one of the aldehyde.N=9.53.C,,H,,O,N requires N = 9.65 per cent.4-H~d~oxypZLenyl-a-c~m~ZLoramic Acid,CO,H*C,H,,*CO*NH*C,H,*OH.A brisk reaction occurs when camphoric anhydride and p-amino-phenol atre heated together.The dark-coloured product containssmall quantities of a substance characterised by the intense purplecoloration developed with aqueous alkali hydroxides ; it wascrystallised from alcohol until the mother liquor no longer showedthis reaction. Recrystallisation from acetic acid, after treatmentwith animal charcoa.1, gave small, pale brown prisms. The meltingpoint was somewhat indefinite, the compound sintering a t 236O anddecomposing a t 250O. The product after fusion dissolved inaqueous alkalis, giving deep purple solutions, probably owing tothe formation of a phthalein:0.0986 gave 0.2385 CO, and 0.0648 H,O.0.3641, in 20 C.C.acetone, gave, in a 2-dcm. tube, a, +1.8Oo,The following aq-1 derivatives of a-camplioraniic acid were alsoC = 65.80 ; H =7-30.C,,H2,0,N requires C = 65.98 ; H = 7.22 per cent.whence [aID + 49.16O.prepared RACEMIC ALDEHYDES. 415A rial ysis./-----Derivative. formula. iorni. 11, p. Found. per cent.EinpiiicJ Crystalline Tlleory,o-Tolyl.. .......... C,7H,j0,N Long needles 194-196" N =4.72 4.84?)L-Tolyl ............ H,O,N Necdles 20S--209 N=4*76 4 84a-Naplithyl ......... C?,H=O,N Needles 233-235 N = 4.31 4.31B-Naphthyl.. ....... C',,H,,O,N Lustrous 210-212 3 =4%S 4'314-Ethosyphenyl ... C,sH,,O,N Long needles 195-197 N = 4.35 4.392-Chlorophenyl ... C,,H1,O,NC1 Minute 130-140 C1= 11-22 11'473-Chlorolhenyl ...Cl,FI,O3NCt Leaflets 207-209 C1= 11 *35 11'474-Chlorophenyl ... CIFH2,0,NC1 Prisms 192-194 Cl=ll.38 11'472-Rroniol)lienyl ... C,,H,,O,~Br Vitreous innss about 78 Br= 22.42 22.603-Rromopheuyl ... C,,H2,0,3NIZ.r Srriall tablets 215-217 Br= 22.54 22-60* This compound, together with t1ie:corresponding imidc, has recently been de-These authors give thep-Tolyl * ............ C,,H,,O,N Lcflflets 212-214 N z 4 . 9 6 4.84lI3afletSciystalsscribed by Abati and Notaris (Gazettn, 1909, 39, ii, 219).iiieltiiig poiiit 201-209" for the acid and 131" for the imide.N-Alkyl and Aryl Derivatives of Canbphorimide,By boiling a solution of a N-substituted a-camphoramic acid inglacial acetic acid with acetyl chloride for two hours, and pouringthe liquid into excess of dilute ammonia, the corresponding imideis obtained in almost theoretical yield. The following wereprepared :Analysis.Empirical CrystallineDerivative. for 111 uln . forill.n-Propyl ............ Cl,H2,0,N Prismsn-BIIty1 ... ... ...... ClJH230,N Lath-likeqL-Hexyl ............ C,,H,,O,N Oil;o-Tolyl ............ C17H,,02N Long needlesp-Tolyl ............ C1,H,,O2N Flat prismscrystiilsn- Amy1 ............ C,,H,O,N Oilm-Tolyl ............ C,,HzlO,N Glisteninga-Naphtliyl ......... C,,H2,0,N Stout prismsB-Naphthyl., ....... C,H,,O,N Sniall needles2-Chlorophenyl ... C1,H180,NC1 Plat prisms3-Chlorophenyl ... ClfiH1,O,KC1 Needles4-Chlorophenyl ... Cl,HI8O,N C1 Prisms2-Bromophenyl ... Cl,H180,NBr Sniall prisms3-Rromophenyl ... CI6H,,O,NBr Needles3-Nitrophenyl.. .... C,,H,,O,N, llliornbicleafletsprismsROYAL COLLEGE OF SCIENCE,SOUTH KENSINGTON, S. W.Theory,XI. p. Found. per cent.40-41" C ~ 6 9 . 9 2 69.9511=9-37 9.4261-62 N=6*13 5'91- N=5*50 5.58 - hTz6.31 5.28195-196 K=5*21 5.16117-118 N=5*27 5.16127-1 28211-212167-16s125-126172-173162-163139-140184-1851 4 6.- 147C=74'98H=7*61W=4'68N = 4.57C l = l l 97C1= 12.03N = 4'89Br = 23.57Br = 23 -68N=8*9775'267.754-564.5612-1812-184.8023.8023.809'2