反应详情

A mixture of ethyl 2-amino-4-methylthiazole-5-carboxylate (6.58 g, 35.5 mmol) and NaOH (5.40 g, 135.00 mmol) in tetrahydrofuran (60 mL) and water (30 mL) was heated to reflux overnight. Tetrahydrofuran was removed by evaporation, and the residue was neutralized with 5% hydrochloric acid solution to pH 5˜6. The precipitate obtained was collected by filtration and dried to afford 2-amino-4-methylthiazole-5-carboxylic acid (5.20 g, 94%); 1H NMR (DMSO-d6, 300 MHz) δ 7.63 (s, 2H), 2.30 (s, 3H). MS (ES+) m/z 159.1 (M+1).

1. temperaturewas heated
2. temperatureto reflux overnight
3. customTetrahydrofuran was removed by evaporation
4. customThe precipitate obtained
5. filtrationwas collected by filtration
6. customdried