反应详情

温度

50 °C

Dissolve 2-(4-chloro-phenyl)-4-ethoxycarbonylmethyl-thiazole-5-carboxylic acid ethyl ester (99 g, 280 mmol) in EtOH (500 mL) and add 2 M NaOH (700 mL, 1400 mmol). Heat the mixture to 50° C. for 1.5 h, then cool the solution in an ice bath, and treat with 2.5 M HCl (1 L) and stir for 2 h. Collect the precipitate by filtration, washing with 50% EtOH/water (500 mL), and then washing with water (1 L). Dry in a vacuum oven overnight at 45° C. to give 80.2 g (95%) of the title compound. 1H NMR (DMSO-d6, 500 MHz): δ 13.66 (br s, 1H), 12.55 (br s, 1H), 8.01 (d, 2H, J=8.6), 7.60 (d, 2H, J=8.9), 4.11 (s, 2H).

1. temperaturecool the solution in an ice bath
2. customCollect the precipitate
3. filtrationby filtration
4. washwashing with 50% EtOH/water (500 mL)
5. washwashing with water (1 L)
6. customDry in a vacuum oven overnight at 45° C.