反应详情

To 2-isopropylamino-oxazole-4-carboxylic acid ethyl ester (2.5 g, 10.9 mmol) in EtOH (42 mL) and water (28 mL) was added NaOH (3.1 g, 77.4 mmol). The mixture was stirred at rt for 16 h, then cooled in an ice-bath and acidified to pH 3 with conc. HCl. The mixture was concentrated in vacuo to remove ethanol. The remaining aqueous phase was extracted with CH2Cl2 (3×200 mL). The organic phases were combined, dried over MgSO4 and concentrated to give 2-isopropylaminooxazole-4-carboxylic acid (1.86 g, 87% yield). LCMS found 171 [M+H]+.

1. temperaturecooled in an ice-bath
2. concentrationThe mixture was concentrated in vacuo
3. customto remove ethanol
4. extractionThe remaining aqueous phase was extracted with CH2Cl2 (3×200 mL)
5. dry with materialdried over MgSO4
6. concentrationconcentrated