反应详情

To a stirred solution of compound ethyl 2-benzamido-2-cyanoacetate (0.46 g, 2 mmol) in pyridine (20 mL) was added Lawesson's reagent (0.81 g, 2 mmol). The reaction mixture was heated at reflux for 15 hr. It was then concentrated and diluted with EtOAc (40 mL). The diluted mixture was washed with water (3×20 mL), brine (10 mL), dried over Na2SO4, filtered, and concentrated in vacuo. The residue was purified by silica gel column chromatography (10:1 PE/EtOAc) to afford ethyl 5-amino-2-phenylthiazole-4-carboxylate (0.2 g, 40%) as yellow solid: 1H-NMR (CDCl3, 500 MHz) δ (ppm): 7.80 (d, J=6.5 Hz, 1H), 7.36-7.41 (m, 3H), 4.43 (q, J=7.0 Hz, 2H), 1.44 (t, J=7.0 Hz, 3H); MS (ESI) m/z: 249 [M+H+].

1. temperatureThe reaction mixture was heated
2. temperatureat reflux for 15 hr
3. concentrationIt was then concentrated
4. additiondiluted with EtOAc (40 mL)
5. washThe diluted mixture was washed with water (3×20 mL), brine (10 mL)
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe residue was purified by silica gel column chromatography (10:1 PE/EtOAc)