反应详情

温度

0 °C

4-Amino-2-bromothiazole hydrobromide (52 g, 0.2 m) was suspended in acetic anhydride (200 ml) then treated dropwise with pyridine (100 ml), maintaining the temperature at 0° C. by means of an ice bath. After the addition was complete, the reaction mixture was stirred for 2 h. at room temperature then poured onto 20% aqueous sodium acetate (2 l). The solution was cooled, filtered and the precipitate washed with water (2×200 ml.). The product was air dried and recrystallised from acetone to give the title compound (35 g, 80%). m.p. 165° C. Found: C, 27.5; H, 2.5; N, 12.7. C5H5BrN2OS requires C, 27.2; H, 2.3; N, 12.7%.

1. additionAfter the addition
2. temperatureThe solution was cooled
3. filtrationfiltered
4. washthe precipitate washed with water (2×200 ml.)
5. customdried
6. customrecrystallised from acetone