Ryan, Algae, and O'Connkll — Syntheses of Some Netv Dyes. 95 



•2774 substance gave 15 - 2 c.cs. moist nitrogen at 16° C. and 761 mm. 1'. 



corresponding to N = 6 - 35, 



C 26 Hi 2 19 NaJS T 4 S 3 requires N = 6-54. 



14. Coupling of Bcnzidine-Sulplionc-Bisulphonic Acid with Sidphanilic Acid. 

 NH 2 SOsNa S0 3 Na NH 2 



I !_ _l I 



/\-N-N— / \ / \_N-N-/\ 



Y x so/ y 



S0 3 Na SOsNa 



The tetrazotised solution of the benzidine-sulphone-disulphonic acid 

 (203 grams) was poured into a cold concentrated solution of 58 grams of 

 sulphanilic acid to which 35 grams of sodium carbonate had been added, 

 and the mixture stirred mechanically for two days. After the first half-hour's 

 stirring a solution of 20 grams of sodium carbonate was slowly added so that 

 the whole was used up by the end of the second day. On standing overnight 

 the mixture was heated on a water-bath to 80° C, and the colouring matter 

 precipitated by the addition of common salt, when it was filtered and dried. 

 The compound was purified by bringing it quickly into solution in hot water, 

 in which it was easily soluble to a deep-red solution, which, on cooling, 

 deposited the dye-stuff as a deep orange-red amorphous powder. It was 

 hardly soluble in cold water. In spite of successive purifications the substance 

 was not obtained in a crystalline condition. The compound dyes cotton 

 directly a canary-yellow shade. 



•1640 substance gave 13 - 5 c.cs. moist nitrogen at 17° C. and 770 mm. P., 



corresponding to N = 9'68, 

 C. 24 H u 11 N 6 Na 1 S 5 requires N = 9-74 



15. Coupling of Benzidine- Sulphone-Bisulphonic Acid with Bimethyl aniline. 



S0 3 Na SOsNa 



3 / N -\ _ /- N=N -\ - / \ _ /- N=N -\ /- N \ 



CH3/ X -/ X — < >— / X -/ X CH 3 



x so 2 / 



The dime thy laniline (37 grams) was cooled in ice in a large beaker, 

 and into it was poured, with constant stirring, the solution obtained by 

 tetrazotising, in the usual manner, 20'3 grams of benzidine-sulphone- 

 disulphonic acid. The mixture was stirred vigorously for two days. After 

 stirring for half an hour a solution of 35 grams of sodium carbonate was 



