NEVILE AND WlNTHER ON ORCaTOL ETC. 415 LXV.-On O/rcinol and some of the other Dihydroxytoluene. By R. H. C NEVILE and DrA. WINTBER, VARIOUS considerations had some time sinae led US to consider it highly probable that orcinol was a dihydroxytoluene of the constitu-tion 1 3 5 a supposition which has since been shown to be true by Tiemann and Streag (Bey. 1881 1999). In order to satisfy our-selves upon this point and to ascertain if some practicable method for its artificial production could not be found we undertook the research recorded in the present notes. As we were endeavouring to obtain satisfactory proof o$ its exae.t; constitutiou we avoided all methods involving the fusion of a corn-pouiici with a caustic alkali as this method has in some cases been found to cause the hydroxyl-group to attach itself at a position in the benzene-nucleus different from that occupied by the halogen or othei-group which has been eliminated.For this reason we started with the dinitrotoluene 1 3 5 which has bean prepared by Staedel (Ber. 1881 902) from both dinitro-orthotoluidine and dinitro-paratoluidine. We prepared it from tho latter 416 NEVILE AND WINTHER ON ORCIKOL As obtained by us it crystallised in bright yellow needles melting at 92.4". Aaalysis. Empl. 0.2503 gram; val. M = 32.5 C.C. ; t = 11" ; b = 743.5 = 15.13 per cent. N. Theory requires 15.38 per cent. We obtained a yield of from 60 per cent. to 65 per cent. of the theoretical amount. On dissolving the dinitrotoltlene in an alcoholic solution of ammo-nium sulphide it gets warm and the addition of water then causes the precipitation of an orange-red substance.This was dissolved in dilute hydrochloric acid filtered and reprecipitated by ammonia. This nitrotoluidine crystallises from alcohol and ether in red-brown lancet-shaped needles. There is frequently mixed with it a lighter-coloured . body which is less easily soluble in ether- or dilute hydro-chloric acid and may modify the characteristics of the nitrotoluidine. The best method of purification appears to be to dissolve the nitro-toluidine in hydrochloric acid and leave it for 12-24 hours in a warm place when a white precipitate gradually forms. This must be filtered out and the liquid again left and the filtration repeated until no further precipitat,e separates on standing or warming.This white substance melts at from 170-180" and appears to be the result of imperfect reduction. The purified solution will now give by neutralisation with ammonia, a precipitate which should be washed dried and crystallised from ether or alcohol. We thus obtained it in thick needles melting at 98-98-4". It is very easily soluble in ether also in alcohol and benzene and somewhat so in water. The salts appear to dissolve freely in water only in presence of an excess of acid. The chloride appears to give up a portion of' its acid on drying in the air or washing with ether. Analyeis. Empl. 0.2893 gram; vol. N = 45.5 C.C. ; t = 13.2'; b = 758.6 = lS.47 per cent. N. Theory requires 18.42 per cent. N. We obtained a yield equal t o about 50 per cent.of the dinitrotoluene used. The nitrotolliidine wits now dissolved in a warm mixt'ure of equal uolumes of sulphuric acid and water and cooled whereupon the sul-phate crystallised out. An aqueous solution of potassium nitrite was now gradnally added until the salphate was all redissolved. An equal volume of water was now added and the mixture warmed wherFupo AND SOhIE OF THE OTHER DIHYDROXYTOLUENES. 417 the diazo-compound was decomposed with evolution of gas and nitro-wesol formed. This oil and the ethereal extract of the mother-liquid were boiled with water and filtered hot. By this means most of the pitch &c. was left on the tilter and the filtrate on cooling gave thick bright yellow needles of nearly pure nitro-cresol. These were purified by crystallisation from benzene or water.Thus obtained it crystallised in bright yellow needles or prisms, very soluble in ether or alcohol less so in benzene and still less in water easily soluble with a dark yellow colour in alkalis or their car-bonates. It does not distil with steam. When crystallised from benzene its melting point is 90-91" but when crystallised from water., 60-62". This arises from its crystallising with water as will be seen below. By heating to 100" a sample which melted at 60-6Z0 or by drying it over sulphuric acid or by recrystallising i t from ether or benzene, its melting point was raised to 90-91". If this was left long iit the open air it attracted moisture and then again melted at 60-62". In order to determine the amount of water of crystallisation some was left over sulphuric acid for various times.This separated as a brown oil. Gram. M.p. Gram. Percent. M . p Empl. 0.1549 60-61" left for 7 days lost 0.0161 = 10.39 81-86'" , 0.5307 60-61 , 6 , 0.0534 = 10.06 81-85 , 0.3160 61-62 , 5 , 0.0330 = 10.44 87-89 1 molecular proportion of water would amount to 10.52 per cent. Ana.lysis of some Crystallised from Benzene and then Dried over Sulp huric Acid. Empl. 0.2171 gram; vol. N = 17.5 C.C. ; t = 12.5"; b = 742.2 = 9.3 per cent. N. Theory requires 9.15 per cent. The yield was about 65 per cent. of the theoretical amount. The nitro-cresol was now reduced with tin and hydrochloric acid : after removal of the tin the liquid was evaporated during which pro-vess it turned brown.The crystalline chloride was washed with ether to remove uiireduced nitro-cresol and was then used for con-version into dihydroxytoluene. In order to obtain dihydroxy-toluene 1 3 5 from the chloride 1 gram of this latter was dis-solved in a hot mixture of 13 grams sulphuric acid with an equal volume of water the solution was diluted with 100 grams of water. cooled by a freezing mixture and a solution containing 0.6 gram of potassium nitrite added. The decomposition of the diazo-compound The base itself was not isolated 418 NEVILE AKD RIXTHER ON ORCINOL thus formed commences between 30" and 50". The liquid was warmed to expel all the gas and complete the decomposition; then filtered and extracted with ether. In this way we obtained a red-brown oil which was purified by frequent distillation and crystallisation from benzene or chloroform.Thus we obtained it from chloroform in glittering white leaves and from benzene in long needles or prisms. After drying for 14 days over snlphuric acid it melted at 106-108". Analysis. R C Empl. 0.1653 H,O = 0.0932 = 6-26 p. c. Theory for C6H,,CHI, (OH), requires. . . . . . . . . . . . . . . . = 6.45 ,, The question now remained ms this identical with the orcinol obtained in other ways? We compared it in all its reactions (viz., ammonia and moist air chloride of lime ferric chloride sodium hydrate in air sodium hydrate in chloroform) with orcinol otherwise obtained and found them all to agree perfectly with the exception of the melting point. Lamparter (Juhresb.1865 589) gives 8s the melting point of anhy-drous orcinol obtained from lichens 86" and when crystallised from water 58'. Vogt and Henniger (Jahresb. 18i2 410) find €or the melting point of the orcinol they obtained from chlorotoluene-sulphonic acid 57*1" when crystallised from water. We examined some orcinol obtained from Messrs. Hopkin and Williams and found that although it agreed in all other respects with the descriptions usually given of orcinol yet that the melting point varied from 56" to 107" accordingly as crystals or fine powders were taken and according to whether the temperature was raised slowly or fast. It appears certain that by very slow raising of the tempera-ture the combined water is driven off and then the orcinol melts at the higher point.In frying the dihydroxytoluene prepared by our method (when crystallised from water) we got sometimes from 54-56' sometimes By distilling the orcinol from Hopkin and Williams between two watch-glasses and by fractionating the distillate by changing the upper glass we got-9 0.1611 H20 = 0.0911 = 6.28 , COZ = 0.4007 = 67.83 P.C. 67.74 ,, 54-105". For 1st distillate m. p. 5 6 81.6" 77 2nd Y , $2- 83.0 9 9 3rd 9 107-108.5 , 4th and 5th , , 107-108. AND SOME O F THE OTHER DIHYDROXYTOLUENES. 419 Treating the substance obtained by u s in a similar way we got-For 1st distillate m.p. 54- 55O 9 2nd 9 , 90- 98 9 3rd 9 , 98-103 7 4th 7 , 97-104 It does not appear that by merely raising tbe temperature to 100" On placing Messrs. Hopkin and Williams' orcinol in a partial vacuum the whole of the water can be satisfactorily driven off.over sulphuric acid the melting point after 24 hours was-106.5-107.5" After 8 days 106~5-10b~O and the same after 14 days. Our substance similarly treated gave after 24 hours m.p. 104-105" After 8 days , 105-107 9 14 9 9 , 106-108 Some of Messrs. Hopkin and Williams' orcino1 which had been dried Theory = 67-74 H20 = 0.1253 = 6-16 , H. , = 6.45 It appears therefore cei-tain that the dihydroxytoluene 1 3 5 , obtained in the manner we have described is identical with orcinol. The melting point of orcinol when containing water seems to be about 56" but the actual point of complete fusion is very hard to determine. When the compound is anhydrous or nearly so the melting point seems to be 106*5-108".It appears very hard to remove the last traces of water. Some orcinol from Messrs. Hopkin and Williams was placed in vacuo over sulphuric acid. Empl. 0.3230 gram; after 45 hours it had lost 0.0254 = 7.86 per cent. 5 days , , 0.0301 = 9-32 per cent. for 14 days and which melted at 106.5-108" was analysed-Empl. 0.2261 gram ; CO = 0.5561 = 67.08 p.c. C. (m.p. 106*5-7.07.5"). 12 9 , , 0.0373 = 11.55 ,, (m.p. 106*5-108"). Again-Empl. 0.3496 gram; after 25 hours it had lost 0,0321 = 9.18 per cent. 10days , , 0*0408 = 1'1.5 ,, 12 9 , , 0.0411 = 11.73 per cent. (m.p. 107-108"). (m.p. 107-108'). Theory for C6H3,CH3(0H) + H20 requires 12.67 per cent 420 NEVILE AND WINTHER ON ORCINOL The artificially-prepared orcinol appears to behave in the same way.Empl. 0.1 gram ; after 4 days it had lost 0.0114 = 11.4 per cent. , 12 , , 0.0125 = 12.5 ,, I n further prosecution of our researches we have succeeded in preparing orcinol by other methods viz. from metabromo-toluene-metasulphonic acid. This was described by us in this Journal 1880, 627 and Ber. 1880 1944-1948. By taking the potash salt of this and fusing it with twice its weight of caustic potash at a temperature of about 280-300" for from half-an-hour to one hour a mass was obtained which was dissolved in water and acidulated extracted first with benzene to remove bye-products and then with ether. The ethereal extract on evaporation left a brown oil which by distillation gave a white distillate slowly becoming crystalline. A fractional distillation of this substance after cry stallisation from water gave distillates as follows :-1st m.p. 54- 56" 2nd , 54-100 2rd , 98-103 4th , 100-104 Some dried over sulphuric acid had the melting point 103-10S0. Aitaly sis. Theory for C,H3,CH3 (0%. Empl. 0.1863 gram HzO = 0.1057 = 6.31 per cent. H ; 6.45 per cent. CO = 0.4648 = 67.92 , C; 67.74 ,, It gave all the reactions of orcinol with chloride of lime ferric chloride sodium hydrate and air sodium hydrate and chloroform, and ammonia and moist air; and we may therefore conclude that it is identical with the above. We have also prepared orcinol from metabromometatoluidine (described by us in this Journal 1880 432). We dissolved it in a warm mixture of equal volumes of sulphuric acid and water ; on cooling the sulpha$e crystallised out.A solution of potassium nitrite was now gradually added until the crystals were dissolved. Water was now added and the solution warmed when gas was evolved and an oil separated out. This was purified by distilla-tion with steam. The oil slowly solidifies into a mass of white crystals which may be completely purified by solution in dilute caustic soda filtration short boiling acidification and then repeated distillations with steam. The boiling with caustic soda seems t o drive off a substance volatile with steam and insoluble in the soda. As th AND SOME OF THE OTHER DIHTDROXTTOLUENES. 421 substance is slightly soluble in water the mother-liquids should be extracted with ether. This substance melts at 56-57," is very easily soluble in ether and alcohol and somewhat in water.An alysis. requires 42-98 per cent. for monobromocresol. Empl. 0.4120 gram; AgBr = 0.4097 = 42-32 per cent. Br. Theory The metabromo-metacresol thus obtained was heated to 280-300" with twice its weighh of caustic potash for one hour. The melt was acidified and extracted by ether. The ethereal extract was distilled, and in this w.ay we oMained a distillate solidifying into crystals and possessing all the characteristics of orcinol. Orcinol was also obtained from metadibromotoluene by heating it in a closed iron tube with twice its weight of potassium hydrate dis-solved in a small quantity of water for two hours from 280-300". It was further obtained from toluene-metndisulphonic acid. As a starting point we took ortho-amido-toluene-metasulphonic acid and heated 5 grams of it with 15 grams of strongly fuming sul-phuric acid to 150-170" for between half-an-hour and an hour.The miss then dissolved easily in water and was treated with barium carbonate to remove the excess of sulphuric acid. The barium salt filtered a very small excess of sulphuric acid added to remove the barium and the filtered solution evaporated to dryness and dis-solved in alcohol re-evaporated to dryness and redissolved in alcohol and again evaporated. The mass thus obtained was very easily soluble in water ar alcohol but not in benzene. Analysis. Empl. 0.4720 gram ; BaSOI = 0.8234 = 59.89 per cent. SOs. Theory for amido-toluol-disulphonic acid requires 59.92 per cent,.In a previous communication (this Journal 1880 625) we have pointed out that the sulpho-group in the moaosulphonic acid occupies the position para to NH and meta to C&. In order to determine the position of the other sulpho-group we converted the nmido-sul-phonic acid into a diazo-compound by introducing nitrous gas into a mixture of it with alcohol or benzene. The diazo-compound was bailed with water a few drops of nitric acid then added and the whole boiled until crystals appeared on cooling. These were filtered out a few drops more nitric acid added and the liquid boiled again, this operation being repeated as often as any further crop of crystals mas obtained. In this manner six crops of crystals were obtained 422 NEVILE ASD WINTHER ON ORCINOL which all had the melting point 85" and possessed all the properties of dinitroorthocresol.Now this last has the two nitro-groups in the two positions meta to CH, as was pointed out by as in a former communication (this Journal 1880 631) also by Staedel (Ber. 1882 901).* Hence we conclude that the two sulpho-groups displaced by the nitro-groups had the same position and that the acid thus obtained is ortho-amido-toluene-metadisulphonic acid. The para-amidotoluene-metadisulphonic acid may be obtained in an analogous manner. When the diazo-compound of either of these acids is heated with absolute alcohol under pressure the toluene-metadisulphonic acid is formed. The solution is then evaporated after neutralisation with an alkali or alkaline carbonate and on heating the resulting aalt with caustic alkali to from 200" to 300" orcinol is produced in all respects iden-tical with that produced by the other methods described.In pursuing these researches we prepared also the dihydroxytoluene 1 2 4 proceeding as follows :-We start from ortho-nitro-para-toluidine (m. p. 77-78"). 40 grams of thi8 was dissolved in 300 grams of a mixture of 1 vol. sulpburic acid with 16 vols. of water and the solution cooled. This causes the separation of crystals of the sulphate. A solution of potassium nitrite was now gradnally added until all the crystals of sulphate were dissolved. It is best to add the potassium nitrite by a tube reaching to the bottoni of the vessel. 3200 grams of a mixture of equal parts of sulphuric acid and water were now added, and the whole heated gradually until the evolution of gas ceased.On cooling crystals of nitrocresol separated out. The mother-liquor was extracted with ether after the addition of water ; and by evaporation of the ether a further quantity of nitrocresol was obtained. In this manner the total yield of nitrocresol reached about 80 per cent. of the theoretical quantity. In order to purify it the ethereal solution was shaken with animal charcoal or the nitrocresol was crystallised from water. By slow evaporation of an ethereal solution it was obt,ained in hard yellow prisms of m. p. 77-'77*4". It dissolves in alkalis and their carbonates with an orange-red colour but the aqueous solutions of the salts partially decompose on heating. It is easily soluble in ether and alcohol.A finahpis. Empl. 0.3313 gram ; vol. N = 25.5 C.C. ; t = 8" ; b = 747-5 mm. N per cent. = 9.14. Theory for CsH3,CH3,N0,,0H = 9.15. * We in common with Nolting and SaIis (Ber. 1881 982) found the melting point of pure dinitro-ortho-cresol higher than did Staedel viz. 85-8' ; Nolting and Sdia give 86" AND SOME OF THE OTHER DIHYDROSTTOLUENES. 423 This nitrocresol is easily reduced by tin and hydrochloric acid. The solution may be freed from tin by hydrogen sulphide and the fil-tered liquid evaporated to dryness. In this way a crystalline residue of chloride of amidocresol is obtained but it is always coloured brown in the process of evaporation. Any unreduced nitrocresol remaining inay be removed by washing with ether. The chloride is easily soluble in water but on the addition of an alkali or alkaline carbonate or ammonia the liquid becomes brown or green.In order to prepare from this the dihydroxytoluene 1 2 4 one gram of it was dissolved in 13 grams of a warm mixture of equal volumes of sulphnric acid and water. The mixture was now diluted with 100 grams of water cooled by a freezing-mixture and a dilute solution of potassium nitrite added until a slight smell of nitrous acid remained permanent ; an excess of nitrite injures the reaction. The liquid was now warmed from 90" to 95" filtered and exhausted with ether. The ether by evaporation left a brown oil which was boiled with benzene. The benzene was decanted off and distilled and the residue remaining after the benzene had distilled off further distilled.In this way an oily distillate was obtained which after some time crystallised. This was purified by frequent sublimations and cry stallisations from ben-zene or toluene and was thus eventually obtained of melting point Analysis. 104-105". Empl. 0.0953 gram ; H20 = 0-0566 = 6.61 per cent. H. Theory for C6&,CH3,(OH), CO = 0.2364 = 6'7.65 , C. requires,. . . . . . . . . . H = 6-45 per cent. C = 6'7.74 ,, The reactions agree pretty closely with those described by Hakan-son (Ber. 1872 1087) for the dihydroxytoluene obtained by him from the toluenedisulphonic acid prepared from toluene and f aming sulphuric acid and it is probable that they are identical. Since this paper was written Knecht (Ber. 1882 298) has obtained this dihydroxytoluene in a similar manner and gives 103' as the melting point.We have also prepared the dihydroxytoluene 1 2 5. For this purpose we start from the nitro-orthotoluidine produced by the nitration of ortho-acetotoluid and which we showed (this Journal 1880 436) had that constitution. 40 grams of metanitro-orthotoluidine (m. p. 127-129") were dissolved in 300 grams of a warm mixture of equal volumes of sul-phuric acid and water. The mixture cooled and a solution of potassium nitrite carefully added until the crystals of sulphat 424 NEVILE AND WIN'L'HER ON ORCINOL deposited on cooling were all dissolved. 1600 grams of a mixture of 1 vol. sulphnric acid to 2 vols. of water were then added and the mixture gently warmed. The decompositioii of the diazo-compound takes place at a temperature of 70-90'.A brown oil separates out which crystallises on cooling and fine needles form in the liquid. These crystals and a further portion extracted from the mother-liquid with ether were dissolved in ether and purified with animal char-coal. Owing to the formation by the above process of dinitro-ortho cresol as well as mono-nitrocresol the perfect isolation of the latter is difficult. We found that the best method was to dissolve the mixed cresols in potash solution and separate the more from the less soluble portion. (The potassium salt of dinitro-orthocresol is much less soluble in cold potash-solution than the salt of the mono-nitrocresol). We then reprecipitated the cresol with sulphuric acid. By repeating these operations we got the compound tolerably pure.The metanitro-orthocresol thus obtained crystallises from water in fine glittering bright yellow needles melting at 30-34" ; but by drying it on paper or on a water-bath or by crystallising it from ether its melting point is raised to 94.6-95". It is not freely soluble in water but easily in alcohol or ether and also in solutions of alkalis or their carbonates. The salts of the alkalis dissolve in water with an orange-yellow colour. Anal p i s . Empl. 0.2267 gram; vol. N = 17.5 c . ~ ; t = 7.8"; b = 750.3 mm. = 9.02 per cent. N. Theory for C6H3,CH3,NO,,O;H requires 8.15 per cent. N. An easier way of obtaining the pure mononitrocresol was found to consist in boiling the metanitro-orthotoluidine with moderately con-centrated solution of soda until it dissolved.In this way few if any, bye-products except a little pitch seem to be formed. The pitch is easily removed by filtration and by then precipitating the nitrocresol with sulphnric acid extracting with ether and shaking with animal charcoal it may be obtained at once nearly pure and the yield is very nearly theoretical. The nitrocresol obtained in this manner presented exactly the same characteristics as that obtained in the other manner-Amalysis. Empl. 0.2895 gram; vol. N = 23.25 C.C. ; t = 9.6'; b = 757 mm. = It appears from the above that the fluid nitro-orthocresol which Hofmann and Miller (Ber. 1881 571) consider to have the constitution 1 2 5 must have some other constitution. 960 per cent. N. Theory requires 9.15 per cent.N ASD SO^ OF THE OTHER DIHTDROSSTOLUESES. 425 The nitrocresol obtained by either of the above processes is easily yeduced by tin and hydrochloric acid. After the tin has been removed by hydrogen sulphide the chloride of the amidocresol is easily ob-tained by evaporation in good crystals coloured brown by the slight products of decomposition. These were washed with ether to free them from undecomposed nitrocresol. The free amidocresol was not obtained as it decomposed immediately on being set free from its salts giving a greenish-yellow or red-brown colonr to the solution from which ether extracted nothing but a red-brown pitch. In order to obtain the dihydroxytoluene 1 2 5 the chloride of tbe amidocresol was dissolved in a considerable quantity of a very dilute sulphuric acid.To this was added a dilute solution of potassium nitrite until the smell of nitrous acid remained permanent for a short time. More water was then added and the mixture boiled until all disengagement of gas ceased. The cooled and filtered liquid was then exhausted with ether. On evaporation the ether gave red-brown' crystals which were purified by sublimation and recrystallisation from benzene in which they are not freely soluble. It was obtained from benzene in white pearly leaves melting at 124-123" freely soluble in alcohol ether or water. From water it crystallises in colourless crystals which melt at 123-125" and do not appear to contain any water of crystallisation. This dihydroxytoluene was prepared from the nitrocresol obtained from nitro-orthotoluidine by both the above-mentioned methods and in both cases appeared identical.Analysis. Theory for requires H = 6-45 p. c. C,H&H, (OH) 2 Empl. 0.2247 gram; H,O = 0.1480 = 7-31 p. c. H. CO = 0.5567 = 67.56 , C. C = 67.74 ,, This dihydroxytoluene appears to be identical with the hgdrotolu-quinone of Nietzki (Bey. 1877 834) prepared from toluquinone from orthoamidoazotoluene. With soda-solution it gives a pretty blue-green colour which very quickly turns to dark brown. With chloride of lime it turns blue-green as with soda t,hen brown ; but with a weak solution of chloride of lime a brownish-red. Chloroform and soda produce a brown colour ; ferric chloride a brownish-red or in a dilute solution yellow. Ammonia in presence of moisture changes it into a dark brown mass which dissolves in alkalis with a brown colour and the addition of acetic acid to the solution causes the precipitation of brown flocks 426 NEVILE AND WINTHER ON ORCINOL We also made some investigations into the preparation of hydroxy-toluene 1 3 4 starting from metanitroparatoluidine (m.p. 114-115"). Armstrong and Thorpe (Jahresb. 1876 452) obtained by nitration of paracresol a nitrocresol identical with that which Wagner (Ber., 1 874 537) obtained by heating metanitroparacetotoluid with sodium hydrate. This nitrocresol must have the required constitution viz., 1 3 4 unless some molecular change takes place. Wagner by this method however obtained only small quantities. We therefore tried t o prepareit from the diazo-compound in the hopes of getting a better yield.10 grams metanitroparatoluidine was dissolved in 100 grams of a mixture of equal parts of sulphuric acid and water and a solution of potassium nitrite was added until a sample of the solution no longer gave a precipitate of nitrotoluidine on addition of water. The solu-tion was then decomposed by heating 800 grams of a mixture of 1 vol. sulphuric acid and lk-2 vols. of water having first been added. The result however was unsatisfactory as neither in the distillate nor in t,he et,hereal extract was any large quantity of nitrocresol obtained, but only a very little melting at 33". We therefore tried Wagner's method and after some experiments succeeded in getting a very good yield. The best plan is to take say 10 grams and heat it with about 50-100 grams of a 20 per cent.solution of sodium hydrate for 15 hours ; then pour off the liquid and boil the remaining nitrotoluidine with a fresh charge of sodium hydrate repeating this process until it is all dissolved. All the sodium hydrate liquors are then mixed acidified with sulphuric acid and distilled. In this way an almost theoretical yield is obtained ; from 20 grams of nitrotoluidine we obtained 19 grams of nitrocresol. This good yield allows us to assume that no molecular change takes place, and that the nitrocresol has the constitution 1 3 4. The substance when purified was obtained from benzene in yellow crystals melting at 33-33-4O easily soluble in caustic alkalis ether or alcohol but scarcely soluble in water.A portion of this nitrocresol was reduced by tin and hydrochloric acid. After removal of the tin by a current of hydro-gen sulphide the filtrate was evaporated to dryness. The chloride (1 gram) dissolved in 100 grams water and 13 grams sulphuric acid, cooled by a freezing mixture and 0.6 gram of potassium nitrite in solution added. The solution was then warmed filtered and extracted with ether. An oil was thus obtained which dissolved easily in water. The aqueous solution was coloured green by ferric chloride, on adding ammonia or sodium carbonate gradually the colour became first blue and then violet. Its properties This oil is probably the dihydroxytoluene 1 3 E AND SOME OF THE OTHER DIHYDROXPTOLUENES. 427 - - - - ~ -coincide with those of homocatechol which Tiemann (.Ber.1877, 210; and 1878 672) obtained by heating the calcium salt of alpha-homoprotocatechuic acid and from coniferyl alcohol. They also re-garded it as a dihydroxytoluene 1 3 4. It would appear from our investigations as well as those of others, that inasmuch as orcinol evidently has the constitution 1 3 5 those reactions by which it has been obtained from substances of other con-stitution such as chlorotoluene-sulphonic acid (1 2 4) must have involved a molecular change. We subjoin a table of the reactions of the different dihydroxy-toluenes above described. Circumstances have prevented us from investigating the dihydroxytoluene 1 3 4 as fully as we could have wished as also the two others viz. 1 2 3 and 1 2 6 ; but we hope to iwume the investigation at some later date.brown. Reagent. 1 -2 *4. --Ammoniaand damp air. 2. '3 *4. Cliloride of lime. Red after a while a green fluorescence, yellow by transmitted light. Ferric chlo-ride. Brown. Sodium hy-drate and air. Chloroform and sodium hydrate on heating. Orcinol 1 *3 *5. Intense re6 vio-let diss. in alkalis with red-violet co-lour. Acetic acid precipi-tates redflocks. -Deep violet-red, then brown and yellow. Deep black-vio-let. Red. 1.2 -5. Dark brown dis solves in alka-lis with brown colour. Acetic acid precipi. tates brown flocks. --Blue-green then brown. When dilute brown-ish-red. B rownish-red, yellow in di-lute solutions. Pretty blue-green chang-ing to dark-I Reddish then brown then green then blue. Blue changing tc red by additior of acetic acid without an5 precipitation. ~ Yellow. Blue scarcely clraiiging. Rose-red then brownish. Rose-red. ' -Green j on gradual addi-tion of NH, or Na2C03, became blue and then violet. TOL. XLI. 2 428 NEVILE AND WlNTHER ON ORCINOL ETC. NOTE. The above p p e r was written principally in the autumn of 1881, but its publication has been delayed owing to our having applied for protection for the method of manufacturing orcinol and since it was written independent workers have published some of the above results. We have however thought it better to publish the paper in its entirety, at the risk of repenting work already done. We may perhaps take this opportunity of noticing a paper by C. Langer (Ber. 1882 1061-l065) on the law of substitution of aromatic amines and point out that the law he there enunciates is really nothing else than the law which we showed to be true in a communication to this Society in 1880 (this Journal 1880 430) stated in other words