反应详情

To 2-mercaptothiazole-4-carboxylic acid (Ex. 19b, 4.2 g) in 50 mL ethyl alcohol was added 2 mL conc. H2SO4. The mixture was heated to reflux for 8 h and cooled. The solvent was removed under reduced pressure and the residue was poured onto 50 mL ice water. The solid was collected, washed with water and dried under vacuum. The crude product was recrystallized from 8 mL ethyl alcohol to afford ethyl 2-mercaptothiazole-4-carboxylate (2.3 g) as a yellow solid.

1. temperatureThe mixture was heated
2. temperatureto reflux for 8 h
3. temperaturecooled
4. customThe solvent was removed under reduced pressure
5. additionthe residue was poured onto 50 mL ice water
6. customThe solid was collected
7. washwashed with water
8. customdried under vacuum
9. customThe crude product was recrystallized from 8 mL ethyl alcohol