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V. 



SYNTHESES OF SOME NEW SUBSTANTIVE DYES DERIVED 

 FROM BENZLDINE-SULPHONE. 



By HUGH RYAN, D.Sc. ; JOSEPH ALGAR, D.Sc. ; and 



PHILIP O'CONNELL, M.Sc., 



University College, Dublin. 



Read April 22. Published Auoust 13, 1918. 



Since the compounds obtained by coupling naphthols and amines with the 

 tetrazo derivatives of benzidine are amongst the most important of the direct 

 cotton dyes, any further investigation of substances of this type is likely to 

 prove of interest and importance. 



The present paper deals with a number of dyes of the benzidine type, 

 obtained by coupling hydroxy and amino compounds with the tetrazo 

 derivative of benzidine-sulphone-disulphonic acid. 



The preparation of benzidine-sulphone-disulphonic acid is described by 

 P. Griess and C. Duisberg (Ber. 22, p. 2459), who state that it combines, when 

 tetrazotised, with naphthols and naphthol-sulphonic acids, yielding purple to 

 violet dyes, and with naphthylamines and naphthylamine-sulphonic acids, 

 forming red or bluish-violet colouring matters. Itefereuces also occur in 

 Patent literature (Friedlander I, p. 495, and II, p. 408, and Baeyer & Co., 

 D. R. P. 27,954 and 51,497) to red to blue dyes obtained by coupling the 

 above-mentioned tetrazo compound with a- and /3-naphthylamines, and with 

 Schaffer's, " R " and " G " acids. None of the dyes mentioned, however, seem 

 to have been isolated in a pure condition, nor does it appear that any efforl 

 was made to determine their constitution and chemical properties. 



The various colouring matters described in this communication were 

 obtained in a pure condition as sodium salts. Repeated efforts to obtain them 

 as' crystalline substances were unsuccessful. The coupling of the different 

 hydroxy and amino compounds with the tetrazo derivative took place readily 

 in somewhat alkaline solution, and, as a rule the coupling was complete aftei 



K.I. A. PROC, VOL. XXXIV., SECT. B. [J/] 



