OF AROMATIC COMPOUNDS. ?5 



(namely, a mixture of azoxy-stilbene-disulphonic acid, 

 azo-stilbene-disulphonic acid, and dinitro-stilbene- 

 disulphonic acid). 



The reduction, however, must not be continued 

 until amido-compounds result. Other reduction 

 processes are used by the Badische Aniline u. 

 Sodafabrik ' for making naphthazarine from a^a- 

 dinitro-naphthalene or a^a^-dinitro-naphthalene. In 

 these cases intermediate products are first formed in 

 the electrolytic reduction, and these are transformed 

 into naphthazarine by heating. 



The Basel company 2 mentioned above obtains 

 triphenyl-methane dyes by the electrolytic reduction 



of nitro-leuco-bodies of the type NO a C e H 4 .CHR a , 



(4) (i) 



which result in the formation ofthecarbinoles 

 NH-C,H 4 .COH.R, 



(4) 



Ahrens 4 accomplished the electrolyut reduction of 

 py.ridine and the derivatives of pyridine, and obtained 

 piperidine from pyridine, and pipecoline from pico- 

 line. In these electrolyses lead cathodes and 10$ 

 solutions of sulphuric acid were employed. 



If strong sulphuric acid and a platinum cathode 



1 German Pat., 79406. 

 * German Pat., 84607. 



3 In these formulae A" denotes aromatic radicals with primary, 

 secondary, or tertiary amido-groups, or with hydroxyl-groups. 



4 Ztschr. f. Elektroch., 2, 577, 580. 



