DR HOPMANN ON THE ANILIDES. Dec. 13 1848. John 'I'liomas CaoIJer Tice-Pre&kmt in the Chair. Mews. John Blyth M.D. Y. JPusprrLtt J. H. Glaclstone Ph. D. James Napier James Mason aid Tl'illinm Reylin were elected Members of the Society. The following paper mas lead IT'.-Researches o?z the co/ucltiZe Organic Bases. BY DR.A. mT.I~OFhIANN Professor at the Royal College of Chemistry. IT. ANILIDES. In a short note,* communicated several years ago to the Society I pointed out the existence of sevcrd new aiiiline coinpouiids without entering ho.vvever into dctails respecting their properties and without giving the aiialytical data on which my statements were founded. A variety of other researches prevented me from conipleting the study of these snbstanccs and it was but of late that a new reaction 1 met with iii anothcr investigation conipellcd me to return to the subject.111 my paper on ~nelaniline,j-I mentioned that the result of the action of chloride of cyanogen on aniline is very materially influenced by the presence of even small quantities of water either in the aniline OF in the chloride of cganogen. Perfectly anhydrous aniline when exposed to the actioii of chloride of cyanogen pre- viously dried by chloride of calcium is entirely converted into hydro-. chlorate of melaniline in accordance with the formulz 2 (C12B N) + c N C1= C, Ell3 N, H C1, +w L-v-Aniline. Chloride of llpdrochlorate of CyanogPn. IIrlaniline. On separating the base by nicana of potash from the solution * hIenioirs of the Chemical Society vol.III. p. 26. -j-Quarterly Journal of the Chemical Society vol. I. p. 286. 1)R. HOFJIANS ON THE ANILLDES. of this hydrochloyate a mother-liquor is obtained which on evapora-tion yields scarcely a trace of organic matter. Action of chloride of cyanoyen on aniline in the presence of water. -If the action of chloride of cyanogeii on aniline takes place iii the presence of water a different deportment is observed. The mother- liquor from which the nielaniliiie has been separated by an alkali when concentrated by evaporation deposits on cooling slightly coloured acicular crystals the quantity of which is in direct proportion with the amount of water that has been present. By treating aniline with the aqueous solutioii of chloride of cyanogen obtained by passing chlorine gas into a solution of hydrocyanic acid in water the chief product of the reaction besides hydrochlorate of aniline corisists in the above-mentioned acicular crystals whilst only traces of melaniline are separated on the addition of potash.The acicular crystals as will be seen from the subjoined analysis are the anomalous cyanate of aniline or anilo-urea as the compound forinerly was briefly termed. ANILO-'CTRCd.-C A RB-4M I DE-CARBANILIDE. There is no difficulty in purifying the crystals of this substance. Treatment with animal charcod and one or two crystallizations from boiling water are sufficicn t to render thein perfectly colourless. The same compound is produced by mixing a solution of sulphate of aniline and cyanate of potash.After the lapse of some time the liquid becomes turbid and gradually solidifies into a crystalline mass consisting of the new substance and sulphate of potash nhich have separated by crystallization thc former being very soluble in boiling and but slightly soluble in cold watLr. A third method of preparing it consists in passing the vapour of hydrated cyanic acid (as obtdined in the distillation of cyanuric acid) into anhydrous aniline. This experiment however requires particular care; the liquid has to be kept as cool as possible. On passing a rapid current of cyanic acid gas into the base a very powerful evolution of heat takes place under the influence of which the newly-formed compound undcrgoes a further decomposi- tion a substance perfectly insoluble in water being formed to which I shall return in the cou:'sc of this paper.If the liquid has been exposed to a slow stream of gas it gradually solidifies into a crystal-line mass which when dissolved in boiling water deposits crystals of perfect purity on cooliiig. In most cases however a small quantity of the substance insoluble in water is likewise formed. The identity of these products was proved by the following analyses. D’B* MOFMANN ON THE ANILIDES. FOPthe analyses I. 11. and IV. the compound had been prepared by the action of moist chloride of cyanogen on aniline; analysis 111. refers to a product obtained by treating aniline with B current of cyanic acid gas.I. 0.3667 grm. of substance gave 0.8247 , , carbonic acid and 0.1995 , , water. 11. 0.2905 , , substance gave 0.6590 , , carbonic acid and 0.1610 , , water. 111. 0.2878 , , substance gave 0.6456 , , carbonic acid and 0.1595 , , water. N.0-2947 , , substance gave 0-4262 , , platinum. From them numbers the following per-centage composition i~ deduced I. If. 111. IV. c Carbon . . 61.33 61.86 61.17 Hydrogen . 6-04 6.15 6.15 -Nitrogen . * --20051 which leads to the formula c, H N2 02 as may be seen from the following table Theory. Mean of experiments. - 84 61-76 61.45 14equiv. of Carbon . 8 , , Hydrogen . 8 5.88 6.08 . 28 20.58 20-51 2 , , Nitrogen 2 11 1) Oxygen 16 11-78 -1 > , Ado-urea .136 100.00 The formation of anilo-urea in the preceding reactions is easily intelligible; whilst in the two latter cases it is produced either by the direct union of the constituents Aniline. Cyanic acid. Ado-urea. or by a process of double decomposition C,,H7N,HS04 + KC,NO,= C1,H,N2O,+ KS00 U Sulphate of Cyanate of Ado-urea. aniline. potassa. DR. HOFMANN ON THE ANLLIDES. we have in the former a transposition of the chloride of cyanogen with the elements of water in consequence of which hydrochloric acid and cyanic acid are formed 2 C, H N + C NC1 + 2H0 = C,,H,N,HCl -t-C14 H N 0 -v uw Aniline. Chloride of Hydrochlorate of Anilo-urea. Cyanogen. Aniline. The exchange of chlorine for oxygen in this case is remarkable; it does not occur in the presence of ammonia ;by saturating an aqueous solution of ammonia with chloride of cyanogen and subsequent evaporation I did not obtain crystals of urea.Anilo-urea is but sparingly soluble in cold water; boiling water dissolves it in large quantities; if the saturated solution be boiled with an excess of the substance the crystals fuse and sink to the bottom of the vessel in the form of an oily fluid. The compound is likewise very soluble in alcohol and ether. It can be boiled with dilute acids and alkalies without the slightest decomposition. I have repeatedly studied this reaction because at the first glance it appeared to point out the possibility of thus producing anthranilic acid -C, H8N 0,+ 2 HO = C14H N 0,+ NH,? w Anilo-urea.Anthranilic acid. I have not however been able to effect this transposition; both alkalies and acids when employed in concentrated solutions produce different changes. When boiled with a concentrated solution of potash or when heated with hydrate of potash anilo-urea yields aniline and ammo- nia carbonate of potash remaining in the retort C1 H8 N 0 + 2 (KO HO) = Cl H N + NH + 2 (KO CO,). v -Anilo-urea. Aniline. Anilo-urea dissolves in concentrated sdphuric acid without decom-position ;on heating the solution a brisk evolution of pure carbonic acid takes place the residue contains sulphate of ammonia and the conjugated sulphuric acid which &I. Gerhardt* obtained by the action of sulphnric acid on various anilides.’ The brown resi-duary liquid solidifies on the addition of water to a slightly reddish crystalline mass which may be purified by solution in boiling water and treatment with animal charcoal. A slowly cooling solution * Journal de Pharmacie 3 SCr. t. x p. 1. deposits splendid rhombic crystals of considerable size and remark-able lustre. The following equation illusti*atcs this transposition C14H N 0 + 3 H SO = C1211 N S O6 + 2CO + NH SO,. -v Anilo-urea. S u!phanilic acid. Although the behaviour of the acid produced in this reaction left no doubt respecting its identity with mil-sulphuric acid a sulphur determination was nevertheless made. 0.4268 grm. of the acid burned with a mixture of carbonate and nitrate of potash gave 0.5835 grm.of sulphate of baryta corresponding to 18.75 per cent. of sulphur. The formula c, H N s 0 requires the following values Theory. Experiment. -12 equiv. of Carbon . . 72 41.62 -7 , , Hydrogen . .7 4.04 -1 , , Nitrogen . . 14 8.09 I 2 , , Sulphur . . 32 18.49 18*75* 6 > J> Oxygen . 48 27.7'6 -1 , , Sulphanilic acid . . 173 100.00 The method by means of which I first obtained anilo-urea viz. the action of hydrated cyanic acid on aniline very naturally sug-gested the idea that this compound must be considered as an analogue of urea; as urea containing the elements C, II,. Urea . . h' 11 II C N 0 Anilo-urea . . (C1211,) PllT H H C2 N O, and hence the name under which I have described it. This mode of regarding it is however not supported by the chemical deportment of the compound; in anilo-urea we iio longer find a remnant of basic properties.I have vainly endeavoured to combine it with acids in order to produce conipounrls analogous to nitrate or oxalate of urea. The presence of these acids does not increase the solubility of the aniline compound in water and the crystals deposited * The slight excess of sulphur arose from the presence of a trace of sulphate in the carbouate used. DH. HOPMANN ON THE ANILIDES. on cooling retain no acid. My attempts to form a platinum-salt have likewise been unsuccessful. The formula of anilo-urea admits however of another interpreta- tion which is strikingly supported by experimental evidence.The following equation C, H N O,=NH, CO ;C, H6 N,CO shows that we may consider this substance likewise as a double com-pound of carbamide with its conjugated analogue. The existence of such double compounds is by no means isolated; in a Memoir on the metamorphosis of cyaniline which I intend shortly to present to the Society I shall have to describe a body of perfectly similar con-struction viz. a coinpound of oxamide with oxanilide correspond- ing in every respect to the preceding substance. Carbamide-carbanilide . . NH, co; c, 136 N Co Oxamide-oxanilide . . . NH, C 0,;C, H N C 0,. I was very curious to submit this idea to the test of experiment and was fortunate enough to meet with a reaction which leaves little doubt regarding the structure of anilo-urea or carbamide-carbani-Me as the substance more properly should be called.I found that when submitted to the action of heat this compound actually splits into its proximate constituents ; one of which the carbanilide is the principal product of the reaction whilst the other unable to exist at the temperature at which the separation takes place undergoes a further metamorphosis and can be recognized only in its derivatives. In submitting anilo-urea to the action of heat the substance fuses without decomposition ;on increasing howver the tenipcrature above thc fusing point torrents of ammonia are evolved while the liquid in the retort solidifies to a crystalline mass which again liquifies and ultimately distils on a further elevation of the temperature.If the process be interrupted as soon as the evolution of ammonia ceases and the solid begins to liquef? again the residue in the retort con- sists of carbanilide aid cyanuric acid. On treating this mixture with a large quantity of boiling water the whole of the cyanuric acid togcther with a small quantity of the other substance is dissolved. In order to obtain the cyanuric acid the aqueous solution is evapo- rated to dryness and the residue extracted with alcohol when car-banilide is dissolved and the acid remains in a state of purity. The properties of cyanuric acid are so marked that I have omitted to analyse the product ;its comportment with solvents and emitting also the well-known odour of cyanic acid when heated appearing quite sufficient to obviate all chance of mistake DR.HOFMANN ON THE ANILIDES The production of carbanilide of ammonia and of cyanurio acid in this reaction admits of an easy explanation if we recollect that carbamide is actually a submultiple of urea which as is well known when submitted to dry distillation is converted into ammonia and cyaiiuric acid. Two equivalents of the cornpound contain the elements of two equivalents of carbanilide and one of urea 2 C, H N 0,= 2 C13H6 NO + C N H O, -wv Carbamide-carba-Carbanilide. Urea. nilide. and the following equation exhibits the final results of the destruc- tion of carbamide-carbanilide by heat Carbarnide-carba. Carbanilide. Cyanuric acid. nilide. "he substance which I have described in the preceding pages claims some interest as the first conjugated amide which was discovered and as the first member of a class of compounds which has been enriched in so remarkable a manner by the investiga- tions of MM.Gerhardt and Laurent. CARBAMIDE-NITROCARBANILIDE. Before passing to the description of carbanilide itself I have to say a few words respecting a compound closely connected with the above double amide the existence of which I have pointed out in my Memoir on melanilhe.* When studying the action of chloride of cyanogen on nitraniline I noticed that along with basic dinitromelaniline a neutral substance was formed which separated in long yellow needles from the solution of the crude product of the reaction in boiling water.Analysis as might have been anticipated proved this body to be the double amide carbamide-nitrocarbanilide. 0.2706 grm. of substance gave 0.4575 , , carbonic acid = 46.10per cent of carbon and 0-1015 , ) water = 4.16 per cent of hydrogen. The formula requires the following values * Journal of the Chemical Society v. I p. 305. DfC. HOFMANN ON THE ANKLIDES. -Theory. Experiment. 14 eq of Carbon . . 84 46-40 46-10 7 , Hydrogen . .7 386 4.16 3 , Nitrogen . . 42 23.22 -6 9 Oxygen . 48 26.52 -1 , Carbamide -nitrocarbani- lide . . . 181 300-00 The formation of this compound will be evident from the foUowing equation Nitraniline. Hydrochiorate of nitraniline. Carbamide-nitrocarbanllide, L-,,..-J An analogous iodine compound is produced in the reaction of chloride of cyanogea on iodaniline along with diodomelaniline.I have not analysed this compound. CARBANILIDE. This substance is but very slightly soluble in water ; it dissolves more readily in alcohol and ether. The boiling alcoholic solution deposits on cooling beautiful satiny needles which have frequently a reddish tint from which they may be freed by recrystallization from alcohol with animal charcoal. It is inodorous but emits when heated a suffocating odour resembling that of benzoic acid. It fuses at 205O C. and distils without alteration. When speaking of the formation of ado-urea by passing the vapour of cyanic acid into aniline I mentioned that care must be taken to avoid the liquid getting very hot in order to prevent the formation of a secondary product I need scarcely say that this secondary product is nothing but carbanilide which may be easily separated from the accompanying compound.The nature of carbanilide being once understood other methods presented themselves for its preparation The simplest plan DR. HOFMANN ON THE ANILIDES. appeared to be a reproduction of the circumstances under which car- baniide was first obtained by 31.Regnault. On exposing phosgene gas,* the interesting chloride of carbonic oxide for the discovery of which we are indebted to Dr. John Davy to the action of ammonia the two gases solidified into a mixture of chloride of amiiioiiium and carbamide. 2 CO C1 + 2NH = NH C1+ NH, CO.This mixture admits of no complete separation of its two ingredients both compounds exhibiting about the same behaviour with solvents and it was by its reactions only that M. Regnault succeeded in establishing its true nature. The action of phosgene gas on aniline is perfectly analogous to that on ammonia and the products of the reaction being easily separable it affords a striking confirmation of &I. Regnault's original explanation of the phenomenon. Aniline when introduced into an atmosphere of phosgene gas solidifies at once into a crystal- line mixture of carbanilide and hydrochloratc of aniline. The process is attended with a powerful evolution of heat. 2 C, H N + 2CO C1= C, 13 N H C1 + C, H N CO. It suffices to extract the crude product of the reaction with boiling water when the hydrochlorate of aniline is dissolved carbanilide remaining which niaybe obtained in a state of purity by a single recrystailization from alcohol.This is certainlr the simplest manner of obtaining carbani1ide.j- The substances employed in the following analyses were partly obtained by this process (I. and II.) and partly by the action of cyanic acid on aniline (111. aid Ti.) Combustion IV was made with a product formed in the dry clistillation of anilo-urea. 1. 0.4270grm. of substance gave 1.1400 ,) ,)carbonic acid and 0-2200 , ,)water * The name phosgene gas was originally framed by Dr. Day on account of the remarkable manner in which solar radiation promotes the combination of carbonic oxide with chlorine.The co-operation of sun-light however is not absolutely necessary ; Dumas when studying the action of this cornpound on alcohol ascertained that the combitlation likewise took place in reflected light but nicch more s!owly ; I hate lately found that phosgene gas may be readily obtained by pasing carbonic oxide through boiling pentachloride of antimony which hy this treatment is reduced to the state of ter-chloride and this reaction affords e\ en a simple method of qualitatively ascertaining the presence of carbonic oxide in a misture of gases ; for the odour of phosgene gas is so peculiar that it cannot be mistaken by a person nho has once smelt it. .I. Care must be taken howe\er that the phosgene gas contain no free chlorine which gives rise to the formation of a chlorinated compound inipartins a violet colour to the carbanilide and can orilp be separated with Sreat dificolty.Dlt. HOPXANIV ON THE ANILIDES. 11. 0.3325 grin. of substance gave 0.9020 , , carbonic acid and 0.1'171 , , water. 111. 0*3019 , , substance gave 0.8182 , ,> carbonic acid and 0.1610 , , water. IV. 0,2534 , , substance gave 0.6812 , , carbonic acid and 0.1328 , , water. V. 0.4160 , , substance gave 0.3835 , , platinum. Per-ceiitage composition T. 11. 111. IV. V. Carbon . . 72.81 73.90 73-91 73.31 , Hydrogen . 5-72 5.90 5-92 5.82 -Nitrogen . --13.07 The forinula C, H NO = C, H6 N CO requires the following valnes Theory. Mean of experiments 7- 13 eq.of Carbon . . '78 73.58 73-48 6 , Hydrogen . .6 5.66 5-84 1 , Nitrogen . . 14 13.01 13-07 1 , Oxygen . -8 7.75 -1 , Carbanilide . . 106 100*00 The behaviour of carbanilide with both concentrated acids and alkalies agrees perfectly with the formula deduced by analysis. When boiled with concentrated sulphuric acid this substance is con- verted into sulphanilic acid pure carbonic acid being evolved. C, 11 N CO + 2 IISO = H SO C, H N SO, + CO,. L-Y-+ Carbanilide. Sulphanilic acid. Ebullition with concentrated potash solution or fusion with solid hydrate of potash gives rise to the formation of carbonate of potash while aniline distils over. C, H N CO + HO KO = C, H N + KO CO,. LdY-i +-Carbanilicle. Aniline. The same decomposition takes place although less perfectly even yitliont tbc assistance of potash if moist carbanilide is rapidly DR.HOFMANN ON TIfE ANILIDES. exposed to a high temperature and hence the invariable presence of small quantities of carbonic acid and aniline among the products of the distillation of anilo-urea if this substance has not been perfectly dried before the experiment. The peculiar decomposition which ado-urea exhibits under the influence of heat induced me to study the phenomena attending the dry distillation of the corresponding sulphur compound hydrosulpho- cyanate of aniline. Hydrosulphocyanate of aniline is easiIy prepared by saturating free hydrosulphocyanic acid with an excess of aniline. The acid used in my experiments had been prepared by decomposing sulpho- cyanide of lead by hydrosulphuric acid.On evaporating the solution of hydrosulphocyanate of aniline the compound separates in the form of deep red oily drops which only gradually solidify into a crystalline mass. In repeated operations I never succeeded in obtain- ing the salt perfectly colourless. Acth of heat on Hydrosulphocyanate of Aniline. Dry hydrosulphocyanate of aniline when exposed to the action of heat fused at a very moderate temperature and entered soon into a sort of ebullition torrents of hydrosulpburic acid and of sulphide of ammonium being evolved whilst on increasing the temperature a colourless oily liquid distillcd over solidifying in the water of the receiver to a semi solid crystalline mass.The residue in the retort is a slightly coloured resinous substance. In order to purify the cfystalline compound the whole distillate was subjected to another distillation. The liquid which now came over separated into two distinct layers of which the upper one contained a large quantity of hydrosulphuric acid and ammonia whilst the lower one consisted of pure bisulphide of carbon. The products of the dry distillation of hydrosulphocyanate of aniline are therefore an amorphous body remaining in the retort ammonia hydrobulphuric ucid bisulyhide of carbon and a crystalline substance which as the subsequent analysis will prove is a compound corresponding to carbanilide in which the oxygen of the latter is replaced by an equivalent quantity of sulphur a compound represented by the formula Cl H N cs for which I propose the name of XuZphocarbaniZide.The decomposition which hydrosulphocyanate of aniline under- goes when submitted to destructive distillation is perfectly analogous DR. HOFMANN ON THE ANILIDES. to that of anilo-urea. Two equivalents of the hydrosulphocyanate split into two equivalents of sulphocarbanilide and one equivalent of sulphocyanide of ammonium according to the equation 2 (C12H N H C N S) =2 (CISH6N C S,) +NH, C N S, L-V L vw Hydrosulpliocyanate of Sulphocarba-Sulpliocyanide of aniline. nilide. ammonium. Of course we cannot expect in a decomposition of this kind actually to separate the sulphocyanide of ammonium ;this compound like urea being unable to exist at the temperature at which the decomposition takes place.But there is no difficulty in tracing it in its products of decomposition. From the experiments of Professor Liebig we know that sulphocyanide of ammonium when exposed to the action of heat evolves ammonia hydrosulphuric acid and bisul- phide of carbon whilst a residue remains described by Liebig under the name of melam splitting on the further application of heat again into mellon and ammonia. Now I have mentioned already that the distil- late of hydrosulphocyanate of aniline along with sulphocarbanilide actually contains a large quantity of sulphide of ammonium and bisulphide of carbon. The residue in the retort seems to consist of mellon or melam mixed with a small quantity of an aniline com-pound.The comparatively small scale in which I had to work and the difficulty of purifying the mellon compounds prevented me from entering upon a more minute investigation. There is however but little doubt that the dry distillation of hydrosulphocyanate of aniline is illustrated by the above equa- tion. The preparation of sulphocarbanilide by the action of heat on the hydrosulphocyanate of aniline being rather a circuitous pro- cess I tried to obtain the same compound by means of a different method. The ready production of carbanilide by the action of phosgene gas on aniline appeared to point out the course to be pursued. There was but little doubt that the compound in question would easily be formed by submitting aniline to the influence of a sulphur compound analogous to phosgene gas.A substance of this kind is known but very imperfectly. In his remarkable paper on the con- version of bisulphide of carbon into the bichloride,* Dr. Kolbe states that the first product of the action of chlorine on bisulphide of carbon at high temperatures is the compound c s el. * Liebig’s Annalen Bd. XLV. S.41. DR. HOPMANN OH THE ANILIDES. The purification however of this substance appears to have been attended with so much difficulty that a very satisfactory analysis of it is still wanting. Before recurring therefore to this difficult and still doubtful reaction I tried whether sulphocarbanilide might not be formed by treating aniline with bisulphide of carbon. Action of Bisubhide of Curbon on Analine.Aniline and bisulphide of carbon may be mixed in every proportion. A mixture of this kind when left for some hours begins to evolve hydrosulphuric acid and gradually solidifies into a scaly crystalline mass which after purification is easily identified with sulphocarba- nilide. The reaction is represented by the following equation C, H N + CS = C, H6 N CS + HS. + v Aniline. Sulphocarbanilide. At the common temperature weeks are required for the completion of the process; with the aid of heat the conversion may be effected rapidly. The simplest plan is to fix a large Liebig’s condensor ver- tically into a flask containing the mixture which is gently heated for a day or two in a sand-bath over a gas flame. The presence of alcohol I find considerably accelerates the conversion.As soon as the evolution of hydrosulphuric acid ceases the digestion is inter-rupted and the crystals are freed from the remaining bisulphide of carbon by ebullition. One or two crystallizations from alcohol render them perfectly pure. The action of bisulphide of carbon on aniline presents a most remarkable analogy with the decomposition occurring in a mixture of the same compound with ammonia. The experiments of Zeise have proved that an alcoholic solution of bisulphide of carbon when saturated with ammonia is gradually converted into the same ammonium compound which hlr. Yorret long ago obtained by satu- rating his hydrosulphocyanic acid with ammonia viz. into sulpho- cyanide of ammonium.Xow sulphocyanide of ammonium although widely different in its chemical nature from sulphocarbanilide never-theless presents a striking analogy to this compound. Sulpho-cyanide of ammonium is a niultiple of sulphocarbamide. RTH, C N S = C If4 N S = 2 (XH, CS) The modes of production of sulphocyanide of ammonium and sulphocarbanilide thus become perfectly parallel as may be seen by the two following corresponding equations - DR. HOPMANN ON THE ANILIDES. NIT + c s = N €I, c s 3. II s. Sulpho-cyanide of animonium. C12II N + C S = C 11 N C S + H S. c,,J C7-J Aniline. S Lilphocarbanilide. For the following analyses the compound was obtained in different preparations. The product employed in the first combustion was formed in the dry distillation of liyclrosulphocyanate of aniline ; the other analyses werc made with the compound obtained by the action of bisulphide of carbon on aniline.I. 0.247’7grin. of substance gave 0.6219 , > carbonic acid and 0.1201 , , water. 11. 0.2891 , , substance gave 0.7253 , , carbonic acid and 0,1365 , , water. 111. 0.3259 , , substance gave 0.8120 , , carbonic acid and 0.1542 , , water. IV. 0,4593 grm. of suhstance gave 54.5 C.C. of moist nitrogen at 21O C. and Om 7596 Bar. Of the fo1lo;ving two sulphur determinations the first was made by gradually deflagrating a inivturc of the substance with nitrate of potash arid carbonate of soda. A siiiall qnantity of the compound having bezn volatilized in this opcratioii a sccoiid experiment was made in which the sulphocarbanilide was dissolved in fuming nitric acid which converts it into a substitution-body which is no longer volatile.The solution was evaporated to dryness and the residue deflagrated in the usual manner with nitre and carbonate of soda. V. 0.3809 grm of substance gave 0.3825 , , sulphate of baryta. VI. 0.4985 , , substance gave 0-5105 , , sulphate of baryta. Per-centage composition I. 11. 111. IV. v. VT. - Cahon HydrogenNitrogen . . . . . . 68.47 5-41 - 68-42 5-27 67.95 5.26 - -12.63 - I - Sulphur . . - - - - 13-67 14.04 VOL. 11.-so. v. E DR. EIOFMANN ON THE ANILIDES. the mean of which closely agrees with the values of the formula c, H N s as may be seen from the following table Theory.Mean. 13 equiv. of Carbon . . . 78 68.42 68-28 .6 5-24 5-28 6 , , Hydrogen 1 , , Nitrogen . . 14 12.29 12.63 1 , , Sulphur . 16 14-03 13.85 1 , , Sulphocarbanilide 114 100.00 100-04 Sulphocarbanilide is but slightly soluble in water it dissolves more readily in alcohol and ether the boiling solutions deposit the compound on cooling in beautifully iridescent plates of remarkable lustre. Sulphocarbanilide is distinguished by its bitter taste it is in fact one of the bitterest substances I ever met with. It has a peeinliar smell which becomes more perceptible on heating. It fuses at 140° C. (284OF.) and distils without decomposition. Dilute acids and alkalies have no action on sulphocarbanilide; when concentrated they decompose the compound and these decom- positions are analogous to the corresponding changes of carba-nilide.Sulphocarbanilide dissolves in concentrated sulphuric acid ; on gently heating this substance a brisk effervescence takes place carbonic and sulphurous acids being evolved ; the remaining solution solidifies on the addition of water into a crystalline mass of sulphanilic acid. The equation C,. H N CS + 2 H SO = C, H N S 0,+ CO + HS v -Sulphocarbanilide. Sulphanilic acid. illustrates the decomposition ; it is evident that the hydrosulphuric acid of this equation when coming into contact with concentrated sulphuric acid is decomposed with the formation of sulphurous acid and the deposition of sulphur. In fact on adding to the liquid a sufficient quantity of water to dissolve the sulphanilic acid a muddy solution is obtained from which a large quantity of free sulphur is deposited HS -I-H S04=2H0 + S -+ SO,.On fusing sulphocarbanilide with solid potash pure aniline distils a mixture of carbonate of potash and sulphide of potassium remaining in the retort -* DR. IIOFMAWN ON THE ANILIDES. C, H,N C S+2 (HO KO) = Cl,HP N + KS +KO CO,+HO. + -+ Sulphocar-Aniline. banilide. If instead of solid potash an alcoholic solution of that base be employed the reaction is considerably modified. In this case the oxygen is simply exchanged for sulphur sulphide of potassium and carbanilide being formed which crystallizes on cooling from the alkaline solution in long beautiful needles.C, H N CS+ KO = KS + C1 H N CO. -v Sulphocarbanilide. Carbanilide. The alcoholic solution of potash may be advantageously replaced by protoxide of mercury. Indeed on boiling an alcoholic solution of sulphocarbanilide with protoxide of mercury the red colour of the oxide at once disappears black protosulphide being deposited whilst carbanilide crystallizes from the solution. The rapid action of protoxide of mercury on the sulphur compound induced me to examine its behaviour with chloride bromide iodide and cyanide of mercury in order to form the corresponding chlorine bromine iodine and cyanogen compounds. These salts however are without action on sulphocarbanilide. The following table embraces the compounds the analysia of which I have communicated on the preceding pages.Carbamide-carbanilide NH CO; C, H N CO Carbamide-nitrocarbanilide NH, CO;C, { tb4 N CO Carbanilide . CIS H N co Sulphocarbanilide . c, H N cs