反应详情

温度

45 °C

A mixture of formic acid (13.1 ml) and acetic anhydride (32.6 ml) was warmed at 45° C. for 45 minutes. After the mixture was cooled until ambient temperature, ethyl 2-(2-aminothiazol-4-yl)-2-cyclopropyloxyiminoacetate (syn isomer)(22 g) was added thereto. The suspension was turned to a clear solution and soon a precipitate was appeared. To the suspension was added diisopropyl ether (50 ml) and the mixture was stirred at ambient temperature for additional an hour. The mixture was cooled in ice-bath and the precipitate was collected and washed with diisopropyl ether to give ethyl 2-cyclopropyloxyimino-2-(2-formamidothiazol-4-yl)acetate (syn isomer)(20.5 g).

1. temperatureAfter the mixture was cooled until ambient temperature
2. temperatureThe mixture was cooled in ice-bath
3. customthe precipitate was collected
4. washwashed with diisopropyl ether