Reaction CLVI.—Action of Hydrogen Sulphide on Diazonium Compounds

Reaction CLVI. Action of Hydrogen Sulphide on Diazonium Compounds. (B., 29, 272.) 

In hydrochloric acid solution the disulphide is ultimately formed—  

On heating a diazonium solution in presence of hydrogen sulphide, nitrogen is evolved, and a mercaptan is formed— 

10 gms. anthranilic acid (see p. 248) are dissolved in 150 c.cs. water and 5 gms. hydrochloric acid. 20 gms. of ice are added and the whole diazotised in the usual way. H2S is passed through the diazonium solution until the yellow precipitate becomes red. C6H4(COOH)N2SH is formed, and after filtration the moist precipitate is dissolved in sodium carbonate solution, and heat is applied until a test portion gives a white precipitate with hydrochloric acid. The solution is acidified with hydrochloric acid and the sulphosalicylic acid filtered off and washed with cold water. 

Reaction CLVH. Action of Hydrosulphides on Alhyl Halides or Sulphates, or on certain Aromatic Halogen Derivatives. 

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