反应详情

To a refluxing solution of thiourea (2.6 g, 34.3 mmol) in absolute ethanol (30 mL) was slowly added at reflux ethyl 2-bromo-3-oxopentanoate (7.3 g, 32.7 mmol). The solution was stirred at reflux for 1.5 hours. After cooling to room temperature, the solution was poured in ice/water (150 mL). The mixture was neutralized with concentrated NH4OH. The solid material was recovered by filtration, washed with water (2×50 mL) and hexanes (3×50 mL), and dried in vacuo, affording ethyl 2-amino-4-ethyl-1,3-thiazole-5-carboxylate (6.8 g, 94% yield). The product was used without further purification.

1. temperatureat reflux for 1.5 hours
2. filtrationThe solid material was recovered by filtration
3. washwashed with water (2×50 mL) and hexanes (3×50 mL)
4. customdried in vacuo