反应详情

4.45 g of 2-mercaptobenzothiazole and 5 g of but-3-ene-1,2,3-tricarboxylic acid are ground together in a mortar. The powdered mixture is introduced in portions into 60 ml of 70% H2SO4 at 48°-50° in the course of 1 hour, with stirring. 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 glutinous sediment and diluted with a further 200 ml of water. After stirring for 1 hour, the precipitate is filtered off and dried. The 4-(benzothiazol-2-ylthio)-butane-1,2,3-tricarboxylic acid obtained has a melting point of 188°-190°, after recrystallisation from methanol/water.

1. stirringwith stirring
2. customThe aqueous solution is decanted from a little glutinous sediment
3. additiondiluted with a further 200 ml of water
4. stirringAfter stirring for 1 hour
5. filtrationthe precipitate is filtered off
6. customdried