Sulfuric Acid → 4-(Benzothiazol-2-ylthio)-butane-1,2,3-tricarboxylic acid

Participants

Reaction Steps

4.45 g of 2-mercaptobenzthiazole, and 5 g of but-3-ene-1,2,3-tricarboxylic acid are ground with one another in a mortar. The powdered mixture is introduced in portions and with stirring into 60 ml of 70% H2SO4 at 48°-50°, in the course of one hour. After a further 3 hours at 48°-50°, the reaction mixture is cooled to room temperature and diluted with 250 ml of water at 25°-30°, with stirring. The aqueous solution is decanted from a little tacky deposit and is diluted with a further 200 ml of water. After being stirred for 1 hour the precipitate is filtered off and dried. The 4-(benzthiazol-2-ylthio)-butane-1,2,3-tricarboxylic acid obtained melts at 188°-190° after recrystallisation from methanol/water.

Provenance & Evidence