Sulfuric Acid → HCID 13101160, compound

Reaction equation

[CH:1]1[S:5][CH:4]=[C:3]2[C:6](=[O:14])[C:7]3[C:8]([C:12](=[O:13])[C:2]=12)=[CH:9][S:10][CH:11]=3.S(=O)(=O)(O)O.[N-:20]=[N+]=[N-].[Na+]>C(Cl)Cl>[CH:1]1[S:5][CH:4]=[C:3]2[C:2]=1[C:12](=[O:13])[C:8]1=[CH:9][S:10][CH:11]=[C:7]1[C:6](=[O:14])[NH:20]2

Participants

Procedure

30.4 g (138 mmoles) of 4,8-dihydro-benzo[1,2-c:4,5-c']dithiophene-4,8-dione are suspended in 200 ml of methylene chloride; 280 ml of concentrated sulfuric acid are then added dropwise, with ice-cooling and stirring. A total of 13.0 g (200 mmoles) of sodium azide is then introduced a little at a time into the well stirred reaction mixture at 0° C. over a period of 2 hours. The mixture is then stirred at room temperature for 8 to 10 hours. The reaction mixture is poured carefully into 3 l of ice-water, with thorough stirring, and the solid which precipitates after a short time is filtered off with suction. The crude product is washed with a large amount of water until it gives a neutral reaction, and is dried at 50° C. under reduced pressure.