反应详情

温度

0 °C

2-Aminothiazole (35 g, 350 mmol) and sodium thiocyanate (89 g, 1.08 mol) in MeOH (400 mL) was stirred at −10° C. Bromine (18.0 mL, 350 mmol) dissolved in MeOH (100 mL) saturated with NaBr was slowly added keeping the internal temperature between −10 and 0° C. After the addition the mixture was stirred at 0° C. for 3 h and the reaction mixture was poured into ice water (1500 mL). Aqueous NH4OH was added to pH ca 8.5 causing precipitation of light yellow crystals which were isolated by filtration, washed with ice water and dried in a vacuum oven to give 30 g (55%) 5-thiocyanato-thiazol-2-ylamine as light yellow crystals.

1. additionwas slowly added
2. customthe internal temperature between −10 and 0° C
3. additionAfter the addition the mixture
4. customprecipitation of light yellow crystals which
5. customwere isolated by filtration
6. washwashed with ice water
7. customdried in a vacuum oven