反应详情

温度

50 °C

A mixture of formic acid (1 l) and acetic anhydride (2.5 l) was stirred at 50° C. for 1 hour and cooled at 40°C. To the mixture were added 7-amino-3-methylenecepham-4-carboxylic acid (1,070 g) and N,N-dimethylformamide (500 ml). The mixture was stirred for 1 hour at 55° C. and cooled in an ice-water bath. A resultant precipitate was collected by filtration and washed with a small amount of a mixture of ethyl acetate and diisopropyl ether (1:1) to give 7-formamido-3-methylenecepham-4-carboxylic acid (1.02 g).

1. temperaturecooled at 40°C
2. stirringThe mixture was stirred for 1 hour at 55° C.
3. temperaturecooled in an ice-water bath
4. filtrationA resultant precipitate was collected by filtration
5. washwashed with a small amount of a mixture of ethyl acetate and diisopropyl ether (1:1)