反应详情

温度

-50 °C

To a solution of benzyl 7β-(2-phenoxyacetamido)-2-oxo-3-cephem-4-carboxylate (294 mg) in methylene chloride (7 ml) were added successively N,N-dimethylaniline (0.17 ml) and phosphorus pentachloride (281 mg) at -35° C. The mixture was stirred for 1.5 hours at -35° to -30° C. and cooled to -50° C. and then thereto was added methanol (0.57 ml). After the temperature was raised gradually to 0° C. over a period of 1.5 hours, water (0.5 ml) was added. The precipitates were collected by filtration and washed with a small amount of isopropyl alcohol to give benzyl 7βamino-2-oxo-3-cephem-4-carboxylate hydrochloride (96.5 mg).

1. temperatureAfter the temperature was raised gradually to 0° C. over a period of 1.5 hours
2. filtrationThe precipitates were collected by filtration
3. washwashed with a small amount of isopropyl alcohol