A solution of methyl 3-bromo-2-oxo-propanoate (10 g, 51 mmol) and thiourea (4.0 g, 552 mmol) in EtOH (200 mL) was added CuOAc (0.3 g, 2.62 mmol), then stirred at room temperature for 10 h. The mixture was concentrated to give the crude product (16 g). The crude product was basified with NaHC03 to pH=8, then extracted with EtOAc (200 mL x 3). The organic layer was washed with H20 (100 mL) and brine (100 mL), and then dried over anhydrous Na2S04, and then concentrated to give the product Methyl 2-Aminothiazole-4-carboxylate (8.0 g) as a yellow solid.
