Ryan, Algar, and O'Connixl — Syntheses of Some New Dyes. 89 



stirring for half an hour, a solution of 50 grams of sodium carbonate was 

 added slowly, drop by drop, so that by the end of the second day the entire 

 solution was used up. The colouring matter was separated as described 

 above, and dried. It was purified from dilute alcohol, and separated as a 

 dark red powder, giving a deep red solution in water. The pure dye stufi 

 acted on cotton directly, giving a navy blue shade. 



0918 substance gave 8'5 c.cs. moist nitrogen at 14° C. and 760 mm. P., 

 corresponding to N = 10 - 89, 

 C 32 H 20 N 6 Na 2 S 3 O s requires N = IPO. 



4. Coupling of Bcnzidinc-Sulphonc-Di&ul phonic Acid with Salicylic Acid 



S0 3 Na SOsNa 



HO—/ V^N = N— / y / y~ N = N<^ J>— OH 



I _ \ sn /_ _ I 



COONa B 2 COONa 



A solution of 16 grams of salicylic acid in 100 c.cs. of cold water was 

 prepared and added to 65 grams sodium carbonate The tetrazotised solution 

 of benzidine-sulphone-disulphonic acid was poured into this mixture, and 

 stirred mechanically for two days. After the first half-hour's stirring a 

 solution of 30 grams of sodium carbonate was slowly added, at such a rate 

 that the whole was used up by the end of the second day. After standing 

 overnight, the colouring matter was precipitated by the addition of common 

 salt after heating to 80° C. on the water bath. It was filtered and purified 

 by separation from hot dilute alcohol. The substance is a reddish-brown 

 amorphous powder, which gives a yellow solution in water, and dyes cotton 

 directly an orange shade. 



•1253 substance gave 7*2 c.cs. moist nitrogen at 17° C. and 760 mm. P., 



corresponding to N = 6"67, 

 C2 6 H 12 1 . 1 NaiN 1 S 3 requires N = 7"07. 



5. Coupling of Benzidine-Sulphonc-Disulphonic Acid with "R-Acid " 

 ((i-Nctphthol-o'd- Disul phonic Acid). 



SOaNa OH S0 3 Na S0 3 Na OH SOsNa 



J_l l_ _l !_l 



/ \ \so./~ / _ \ 



I I 



S0 3 Na S0 3 Na 



The tetrazotised solution of 203 grams of benzidine-sulphone-disulphonic 



