74 ELECTROLYSIS AND ELECTROS YN THESIS 



use of by Lob * in performing a direct electrosynthesis 

 of the mixed azo-bodies and azo-dyes. The com- 

 ponents of the compounds desired, in exactly equi- 

 molecular proportions, are reduced under conditions 

 which render the union of the two residues possible. 

 In this way azo-compounds are obtained in which the 

 substituents are in the meta-position compounds 

 which could not be prepared by the Griess method. 



Kaufmann and Hof a subjected m-nitro-benzal- 

 dehyde to reduction in alkaline solution and thus 

 obtained m-azo-benzoic acid as the principal product 

 and m-azo-benzyl alcohol as a secondary product. By 

 the electrolysis of m-nitro-benzaldehyde Lob 3 ob- 

 tained m-azo-benzoic acid and m-azo-benzyl alcohol 

 as secondary products. The chief product consisted 

 of a mixed azo-body, azo-m-benzyl-alcohol-m-benzoic 

 acid, 



m - CH 3 OH.C 6 H 4 .N : N.C,H 4 .COOH - m. 



The Gesellschaft f. Chem. Industrie of Basel* 

 prepare orange dyes by using as cathode fluid an 

 alkaline solution of the yellow condensation products 

 of p-nitro-toluene-sulphonic acid, 



CH '- C H '\S0 3 H 



1 Ztschr. f. Elektroch., 4, 530. 

 8 Chemiker Zeitung, 1896. 

 * Ztschr. f. Elektroch., 4. 

 4 English Pat., 22482. 



