828
W. J. KARST,.\KT:
. \ X I ) \V.
J. .\IORGAS.
of no particular importance; we have found it convenient to take a n amount approxiinatel!, equal t o that of the Inaterial u:idc.r e?ia!iiination. The method has been tested b y tlic junior author, who recciwtl a number of mixtures, tlic coi-iposition of each of \vhicli was u n k i i o ~ r to ~ i liin:. His results were accurate to 2 pc'r cent. and ill so:i:c cases agreed c v r ~ i more closely. In dealing with ternary mixtures it is advisable to crystallize then1 fractionall). from alcohol once o r t\vic.i.. 111 this 1i:uniler \ve have foulid that we could obtain two portions, one containing substantially all t lie orthonitraniline together with soiiie iiieta-, \vliile the other portion consisted of the nieta- and paraisoniers. \lye. i i a l ~~ n a d ea few esperiii:cnts on the separatioii of ortho- arid paranitraniline by cr!.stallizatiori. So far as we can judge, the separdtion ciiii l x 1i:;ldc yuantitativcl!.. 'l'hc mixture is weighed and treatctl with just sullicielit boiling alcohol (9j per cent.) to dissolve it. c.001, tlie i.oluliic is i::easurcd. The paranitraniline which deposits is collected am1 to its w i g h i is 2:dded that of the quantity dissolved in the filtrate; tlie sum of thesc, subtracted froill the weight of thc original material, rcpr 111s the orthonitraniline.
Summary, I. Curves have been constructed slio\ving the relationship between the melting points and t h e co~npositionof tlie three binary iiiixtures of the isomeric nitranilines. 2. In the case of the mixtures of ortho- aiid nicta- arid of nieta- and paranitraniline, these curves arc comparatively regular; they fall t o t h e eutectic point aiid then risc t o thc ilielting point oi the pure coiiipouiid. 3. The curL-e representing tlie relationship 1 ) e t w e i l the nielting point and composition of mixtures of ortho- and paranitrariiline is highh. irregular. At present it is impossible to givc a satisfactory explanation of this phenomenon. 4. 'l'he curves ineiitioned ubovc c u i bel used to deterriiiiic tlic coinposition of inixturcs of otho- aiid n!eta-- arid of iiicta- aiid paratiitranilinc, respecti\-ely, by a simple aiid c.spcditious iiict hod which requires aril!, :i 1lii1limal quantity oi iiiatvrial. ' 1 ' 1 1 ~ results arc usually accuratt withiii two per ceiit. McMASTER UNIVERSITY,
TORONTO, CANADA. December, 190;.
__ -SOME DERIVATIVES OF I,~-DIMETHYL-~,~-DINITROBENZENESULPHONIC ACID, BY
W ,J. K A K S L A K K A N 1 ) 11'. J . M O K C A N . lieceireil .\larch to. 190'
'l'he illilia1 material u s ~ t l\vas l h c potassiui~i salt of i .~-diiiietliyl-~,Odinitrobenzene-1-sulptionicacid, nhicli was prepared :is follows :' 800 1
Claus and Schmidt. b'. 19,1424.
I ,3-DIM~THYL-2,6-DINI'I'ROBENZENE-4-SULPHONIC ACID.
829
cc. commercial m-xylene were shaken in a separatory funnel with 800 cc. sulphuric acid, sp. gr. I .84, for about a n hour, no attempt being made t o regulate the rise 'in temperature. After standing for a n hour or so t h e m-xylenesulphonic acid solution was drawn off from the undissolved portion of the hydrocarbons and slowly added, with constant shaking, to a mixture of 1000 cc. of ordinary fuming nitric acid and 500 cc. of ordinary fuming sulphuric acid, the temperature being kept below 100'. After standing twenty-four hours, the mixture was heated to 125-130' for six or seven hours, allowed to cool, and poured into about eight liters of cold water. After filtering off the insoluble precipitate formed, which consists mostly of 2,4,6-trinitro-rn-xylene, the filtrate was heated, neutralized with calcium carbonate, again filtered, and a hot solution of potassium carbonate added in excess. The precipitated calcium carbonate was filtered off, the filtrate evaporated t o a volume of three or four liters and the potassium salt of ~~g-dimethyl2,6-dinitrobenzene-4-sulphonic acid allowed to crystallize out. A yield of 640 grams was obtained and from the melting-point of the sulphonchloride, and sulphonamide, its identity established. It was later learned t h a t a better yield and a purer product could be obtained by isolating the I ,g-dimethyl-6-nitrobenzene-4-sulphonic acid first formed and then nitrating this with about twice its weight of fuming nitric acid diluted d t h double the weight of ordinary sulphuric acid, sp. gr. I .84. The sulphonchloride was made in the usual manner by treating the potassium salt wlth an excess of phosphorus pentachloride, pouring the product into ice-water, filtering and washing, and crystallizing the residue from carbon tetrachloride. It had a melting-point of 123'. z,~-Dimethyl-~,6-d~nitrobenzelze-~-sul~honan~lide.-Twenty grams of aniline dissolved in IOO cc. carbon tetrachloride were added to 2 0 grams of the sulphonchloride previously dissolved in 200 cc. carbon tetrachloride. After heating on the water-bath for two hours in a flask connected with a return condenser the carbon tetrachloride was distilled off, the residue washed several times with dilute hydrochloric acid and afterwards with water. It was then dissolved in a ten per cent. solution of caustic potash, filtered, the filtrate acidified, with dilute hydrochloric acid, and the precipitated anilide crystallized from dilute alcohol. It separated in short, yellow needles which melted a t 154'. It is easily soluble in ether or chloroform, less so in carbon tetrachloride, and insoluble in water. Upon analysis it gave 9.02 per cent. sulphur (Liebig's method) against 9.12per cent. calculated for C,,HsO&N,S. I ,~-Dimethyl-z,6-diltitrobelzzerte-~-szll~hon-o-toluidide. -Five grams of the sulphonchloride dissolved in 30 cc. of carbon tetrachloride were added to four times the equivalent weight of o-toluidine previously dissolved in 100 cc. of carbon tetrachloride and the mixture heated in a flask with
830
W. J. 1
