6O ELECTROLYSIS AND ELECTROSYNTHESIS 



4. The formation of amido-azo-compounds by 

 molecular rearrangement of diazo-amido-compounds. 

 The nitrous and nitric acids were oxidation products 

 of the ammonia which was added. 



INVESTIGATIONS OF GOPPELSROEDER.' 



These relate to aniline and its derivatives, and aim 

 at preparing the most important dyes of the aniline 

 series. Although the reactions which take place in 

 the cell have not as yet been explained, the researches 

 form valuable material for consideration. Goppels- 

 roeder has gathered the technical results in a small 

 pamphlet: " Farbelektrochemische Mitteilungen " 

 (Muhlhausen, 1889). 



If a galvanic current is conducted through acid or 

 neutral aqueous solutions of aniline there is formed at 

 the positive pole, besides other coloring matters, ani- 

 line black, C 24 H ai N 4 Cl. Under similar conditions dyes 

 are obtained at the positive pole from the salts of 

 toluidene, methyl- aniline, diphenylamine, ditolylamine 

 and phenyl-tolylamine. 



Naphthylamine salts give naphthylamine violet. On 

 electrolysis of anthraquinone and potassium hydroxide, 

 Goppelsroeder succeeded in obtaining alizarine. 8 



1 Dingier, Polytech. Journal, 221, 75; ibid., 223, 317 and 634; 

 ibid.) 224, 92 and 209. 

 * See also p. 56. 



