6 111.-On Chlovanil and Bromanil. No. IT. By JOHN LL.D. F.R.S. &c. STENHOUSE CHLORANIL. IN addition to the reactions already known by which Chloranil has been produced I may mention that when phenol was subjected to the long-continued action of chloride of iodine in presence of water it yielded a brown crystalline mass fiom which chloranil was obtained equal to half the weight of the phenol originally employed. I likewise found that when the red oil," obtained in the ordinary process for preparing chloranil was dissolved in a very dilute boiling solution of caustic soda along with a sufficient quantity of potassic chlorate and hydrochloric acid then added it also yielded a small quantity of crystallinescales which proved to be a mixture of chloranil and terchlorquinone.Although the first of these processes is theoretically interest- ing neither of them is adapted for the economical preparation of chloranil in quantity. When the above mentioned red oil was digested for some time with nitric acid sp. gr. 1.36 a considerable evolution of red fumes took place and chloropicrin distilled over into the receiver. The bright yellow residue remaining in the retort was found to be chloraiiil. CHLORANILIC ACID. The following modification of the process described1,:by Graebe,t I have found to be the best for the preparation of this acid. Five parts of chloranil moistened with alcohol were .added to a cold solut,ion containing six parts of potassic hy- drate in 150 of water; the whole was allowed to stand for several hours with occasional stirring until the yellow chloranil scales had disappeared and a portion of the potassium salt had crystallised out in dark red needles.From 10 to 15 parts of chloride of sodium were then added which completely precipi- * Chem. SOC.Jour. 1868 p. 142. t Ann. Ch. Pharm cxlvi p. 31. STENHOUSE ON CHLORANIL AND BROMANIL. tated the chloranilic salt as it is quite insoluble in a cold solution containing 8 to 10 per cent. of sodic chloride. After standing some time the precipitate was collected and fkeed from the dark brown mother-liquor by washing well with a solution of common salt. One or two solutions in boiling water and precipitations by common salt and a final crystallisation from distilled water rendered the chloranilic salt quite pure.It was generally necessary to add a little sodic carbonate each time to the solution to decompose any chloranilate of magne-aium or calcium formed from the chlorides of magnesium and calcium usually present in common salt. The pure chloranilate thw obtained was dissolved in 100 parts of boiling water (about 40 times its weight) and 10 parta of hydrochloric acid added; on cooling the whole of the chlora- nilic acid was deposited in bright red shining scales which were perfectly pure. By this process chloranil yielded from 65 to 67 per cent. of its weight of pure chloranilic acid the theoretical quantity being 84.96 per cent. When caustic soda was substituted for the potassa in the above reaction much less acid was obtained as was also the case when the solutions were heated or when potassic or sodic carbonate was used.Hydrates of calcium and barium and also magnesia were found to decompose chloranil with formation of the corresponding chloranilates. By far the best method however of preparing the alkaline chloranilates in the pure state was first to make pure chloranilic acid and then neutralize this with the corresponding alkaline hydrate or carbonate. The sodium salt when dried at 100' C. was found to lose 12.6 per cent. water ; 2H,O require 12.46 per cent. An analysis was also made of the Same salt dried at looo with the following results :-I. -334grm. substance gave -189 grm. Na,SO,. 11. -379 grm. substance gave -211 grm.Na,SO,. I. 11. Mean. 28.45 --c ......... 72 Cfi ........ 71 28.06 -- Na ........ 46 18.19 18.33 18-04 18.19 0,.......... 64 25-30 -- 253 100*00 STENHOUSE ON CHLORANIL AND BROMANIL. The sodium salt dried at the ordinary temperature is there-fore C,C12Na204 + 2H20. When neutral solutions of chlora-nilate of sodium are boiled they are rather rapidly decomposed with production of a dirty brown substance which remains in solution; but this does not take place when an excess of sodic carbonate is present even at temperatures considerably above looo c. CHLORANILIC ETHER. One part of chloranilate of silver was digested with five of ethylic iodide until the whole of the dark red silver salt was converted into iodide ; the excess of iodide of ethyl was distilled off and the chloranilic ether extracted by boiling alcohol in which it was tolerably soluble.When well washed with hot water and crystallised once or twice from spirit it was quite pure. It is soluble in benzol light American oil bisulphide of carbon and ether and slightly soluble in boiling water. It crystallises in flattened prisms of a bright red colour and melts at 107O C. Dried at looo C. and submitted to analysis it gave the followiiig results :-I. ,301 grm. substance gave -500 grm. carbonic anhydride and *lo8 grm. water. 1. c, ............ c1 ............ 120 71 45.29 26-80 45.31 - H, 0 ............ ............ 10 64 - 3-76 24.15 3.98 - 265 1oo*oo The ether as might be expected is therefore C6C1,(C,H,),0,.Action of Nitric Acid on Chlornnilic Acid.-When pure chlora- nilic acid was warmed with twice its weight of nitric acid sp. gr. 1.45 a strong reaction ensued chloropicrin distilled over and a white crystalline substance remained in the retort which on analysis of the lime salt proved to be oxalic acid. Action of Cldoride of Iodizze on CJdoranilic Acid.-When a cur-rent of chlorine was passed through chloranilio acid suspended in water the acid very slowly disappeared so that even after several days the greater portion remained unacted on. I was therefore induced to try the action of chloride of iodine. Three parts of pure chloranilic acid about one of iodine and six of STENHOUSE ON CHLORANIL AND BROMANIL. 9 water were placed in a flask and a slow current of chlorine passed through the mixture which was kept warm until the chloranilic acid had entirely disappeared and an oily layer had collected at the bottom of the flask.On cooling large trans- parent plates crystallised out of the supernatant liquor and the insoluble lime-salt of this acid was dried at 103O and analysed. -540 grm. lime-salt gave 0501calcic sulphate which is equiva- lent to 27-35 per cent. calcium; %y4'}02 + H,O requires 27.39 per cent. The plates are therefore oxalic acid. The heavy oily layer which has an odour analagous to chloropicrin J am at present investigating. Action of Bromine on C7Joranilic Acid.-Two parts of chlora- nilic acid we're suspended in 20 parts water and three parts bromine gradually added with constant agitation until the chloranilic acid had completely dissolved forming a pale yellow solution.On the addition of two parts more bromine the liquid became warm effervesced slightly and after standing 24 hours deposited a white crystalline precipitate. This was collected well washed with cold water in which it was quite insoluble dried at a gentle heat and crystallised several times &om bi-sulphide of carbon. The substance dried in vacuo gave the following results :-I. -396 grm. gave -124 grm. carbonic anhydride. 11. 0455grm. gave *145grm. carbonic anhydride and -009 grm. water. 111. *432 grm. gave 0778grm. bromide of silver and -221 grm. chloride of silver. IV. -361 grm. gave -646 grm. bromide of silver and 0181 grm.chloride of silver. I. 11. 111. IV. Mean. C,. . .... 72-0 8.62 8-54 8-70 -8.62 Br .... 640.0 76.60 -76-63 76.14 76-39 C1 . . .. 106.5 12-75 -12.66 12.41 12.54 H. ..... 1.0 -12 -22 --22 16.0 1.91 ---835.5 100.00 This corresponds very closely to C,Br,Cl,HO but I abstain from naming it as at present I have been unable to verify this STENHOUSE ON CHLORANIL AND BROMANIL. formula and wait therefore until the investigation of the cor-responding oily chloiine compound mentioned above shall have thrown some light on the subject. The substance is very soluble in bisulphide of carbon from which it crystallises by slow spontaneous evaporation in very large colourless prisms. It dissolves in alcohol but is at the same time partially de- composed as on evaporation of the solution even at the ordinary temperature aldehyde is given off and an oil remains.It diasolves readily in benzol and ether melts at 79.5' C. and dmtils unchanged. It is apparently unaltered by boiling sul- phuric acid. BROMANIL. This substance which I described in 1854,"wasprepared by the action of bromine on picric acid but the quantity obtained was small in proportion to the amount of bromine and piciic acid employed bromopicrin being the chief product. The process moreover was a very tedious one After making numerous trials to discover a better method of preparation I found the following to be far the best as by it bromanil can be obtained nearly as easily as chloranil. A known qnantity of bromine was placed in a flask with one- third its weight of iodine and five times its weight of cold water.A good cork furnished with a long digestion tube was inserted into the neck of the flask and a quantity of phenol equal in weight to one-tenth of the bromine slowly introduced down the tube ; a powerful reaction took place and the contents of the flask became very hot. The phenol adhering to the sides of the tube was then washed down by five parts more boiling water and the whole digested for one or two hours at 100" C. When cold the semi-solid contents of the flask were collected freed as far as possible from the mother-liquors by means of Buns e n's admirable vacuum filter and digested once or twice in the cold with bisulphide of carbon in order to re-move the terbromophenic acid formed during the reactioc.This lee the now tolerably pure bromanil undissolved as yellow crystalline scales closely resembling in appearance crude chloranil which after being treated once or twice with boiling alcohol and finally crystnllised from purified benzol (16 parts) was obtained in a state of purity. * Ann. Ch. Pharm. xci p. 339. STENHOUSE ON CHLORANIL AND BROMANIL. 11 -601 grm. dried at 1OOOC. gave ~371grm. carbonic anhydride and 1.014 grm. water. 1. c .............. 72 16.98 16-54 I Br ............ 320 75-47 0 .............. 32 7.55 - .I_-424 100.00 BEOMHYDRANIL. Although as I have previously stated,* aqueous solu-tion of sulphurous acid converts bromanil into bromhydranil there is a considerable loss owing to the formation of secondary products and it has a brown colour which is extremely difficult to remove.I found however that as in the case of chlorani1,t when bromanil was digested with hydriodic acid and phosphorus it gave the theoretical quantity of colourless bromhydranil C6Br402,H2. Action of Xubphui*ousAcid on Bromanil. TERBROMHYDROQUINONE. Although bromhydranil was the principal product obtained in passing sulphurous anhydride through boiling water holding bromanil in suspension about 17 per cent. was converted into an organic acid which remained in solution along with the sulphuric and hydrobromic acids fbrmed at the same time. This solution was neutralized with carbonate of lead and the resulting product submitted to sub1imat)ion in a manner pre- cisely similar to that employed in the case of the corresponding cbloranil compound.$ The yield of terbromhydroquinone was however very small the greater portion of the substance under- going decomposition.Owing to the smallness of the quantity I obtained I was unable to subject it to analysis ; but from the similarity of its reactions and physical properties to those of terchlorhydroquinone it is undoubtedly the corresponding bromine compound C,Br,H,O terbromhydroquinone. * Ann. Ch. Pharm xci p. 310. f-Chem. SOC.Jour. xxi p. 145. 2 Chem. SOC.Jour. xxi p. 146. STENHOUSE ON CHLORANIL AND BROMANIL TERBROMOQUINONE. When the above-mentioned solution obtained by the action of sulphurous acid on bromanil was concentrated by evapora-tion and sulphuric acid and acid chromate of potassium added in excess a brownish-yellow precipitate was produced con-sisting of terbromoquinone c6Br3Ho2 which wzs readily purified by one or two crystallisations from dilute alcohol in which it is very soluble.Its physical characteristics and chemical properties resemble those of terchlorquinone. BROMANPLIC ACID. This acid was prepared in a precisely similar manner to chloranilic acid which it resembles very closely in appearance and properties. The action of nitric acid upon it was as might be expected similar to that on chloranilic acid brolnopicrin and oxalic acid being the chief products. Alkaline sulphites also produced the corresponding salts of bisulpho-lsibrom-hydro-and c6JHO chinonic and thiocronic acids c6{ Br,::::& (Hso,)O, 1@Sod4 The action of an aqueous solution of sulphurous acid on bromanilic acid at 100' does not appear however to pro-duce the acid corresponding to KOch's hydrochloranilic acid C6C1,H4O4.BROMANILPHENYL AMIDE. This compound analogous to the corresponding chlorine body discovered by Hesse,* was best obtained by adding an excess of aniline to brornanil dissolved in hot benzol and wash- ing the almost black crystalline plates which are formed with boiling alcohol in which they are nearly insoluble. Dried at 100' C. they gave the following result :--420 grm. substance gave -357 grm. bromide of silver :-* Ann. Ch. Pharm cxiv p.303. STENHOUSE ON CHLORANIL AND BROMANU;. 13 I. C18.......... 216 48.20 - HI ........ 12 2.68 - Br,. ......... 160 35-73 35-56 N .......... 28 6.25 - 0 .......... 32 7-14 - 448 100*00 This corresponds to the formula Action of Bromine on B?qornaniZic Acid.-When three parts by weight of bromine were gradually added with constant stirring to one part of bromanilic acid suspended in eight parts of cold water the bromanilic acid dissolved forming a transparent deep yellow solution which at the same time became warm and effervesced slightly. In a short time the clear solution lost its transparency and after standing 24 to 48 hours deposited a large quantity of indistinct crystals more than equal in weight to the bromanilic acid originally employed (1.25 parts).These were collected well washed with cold water in which they were quite insoluble and crystallised two or three times from pure and dry bisulphide of carbon. They were thus obtained in colourless transparent prisms which melt at l10°5 C. and are very soluble in ether bisulphide of carbon and benzol. They are also soluble in alcohol but apparently undergo decomposition at the same time. Dried at 100' C. they gave the following results :-I. *675 grm. substance gave *183 grm. carbonic anhydride and *009grm. water. 11. -538 grm. substance gave -147 grm. carbonic anhydride and *005grm. water 111. el87 grm. substance gave 0399grm. bromide of silver. IV. ,373 grm. substance gave *797 grm. bromide of silver.1. 11. 111. JV. Mean. C6. ..... 72 7-43 7-40 7.45 -7.43 Br, .-. . 880 90.82 -90.80 90.93 90.86 H ...... 1 *lo *15 *10 --12 0 ...... 16 1-65 ---___. -I-969 100.00 WANKLYN ON SALTS ON ACETYLINATED ETHYL. This agrees tolerably well with the formula C,Br,,HO. I cannot conclude this paper without expressing my obliga- tions to Mr. Charles E. Groves for the very efficient assiitance he has rendered me in this investigation.