反应详情

温度

0 °C

2.8 ml. (0.02 moles) of triethylamine are added to a suspension of 3.8 g. (0.01 mole) of 7-amino-3-methyl-ceph-3-em-4-carboxylic acid trichloroethyl ester hydrochloride in 30 ml. of methylene chloride. The separated triethylamine hydrochloride is filtered off, the filtrate is cooled to 0° C., and 5.02 g (0.01 mole) of phenylmalonic acid phenylester pentachlorophenyl ester are added. The obtained clear solution is stirred at the same temperature for 30 minutes, thereafter it is washed with 2 n aqueous hydrochloride acid and the solvent is evaporated. The residue is treated with absolute ethanol. 4.7 g. (80%) of 7-(α-phenoxycarbonyl-phenylacetamido)-3-methyl-ceph-3-em-4-carboxylic acid trichloroethyl ester are obtained. The white, crystalline substance melts at 120°-125° C.

1. filtrationThe separated triethylamine hydrochloride is filtered off
2. washit is washed with 2 n aqueous hydrochloride acid
3. customthe solvent is evaporated
4. additionThe residue is treated with absolute ethanol