反应详情

To a solution of methyl 3-[2-(1-{[3,5-bis(difluoromethyl)-1H-pyrazol-1-yl]acetyl}piperidin-4-yl)-1,3-thiazol-4-yl]-4,5-dihydro-1,2-oxazole-5-carboxylate (1-1) (1.1 g) in tetrahydrofuran (7 ml) and water (2 ml) is added, at room temperature, lithium hydroxide monohydrate (0.28 g). The mixture is stirred at room temperature for 20 minutes, and then ice-cold 1N HCl solution is added. The aqueous phase is extracted with ethyl acetate and the combined organic phases are dried over sodium sulphate. The solids are filtered off and the solvent is distilled off. This gives 3-[2-(1-{[3,5-bis(difluoromethyl)-1H-pyrazol-1-yl]acetyl}piperidin-4-yl)-1,3-thiazol-4-yl]-4,5-dihydro-1,2-oxazole-5-carboxylic acid (0.82 g, 73%).

1. extractionThe aqueous phase is extracted with ethyl acetate
2. dry with materialthe combined organic phases are dried over sodium sulphate
3. filtrationThe solids are filtered off
4. distillationthe solvent is distilled off