反应详情

5.6 g of t-butyl 2-bromo-3-bromomethyl-7-phenylacetamido-3-cephem-4-carboxylate 1-oxide, prepared by the procedure of Step C of Example II, were dissolved in 40 ml of trifluoroacetic acid and the solution was stirred for 15 minutes at room temperature. The solvent was then evaporated, diethyl ether was added and the solvent was evaporated again. Diethyl ether was added again and the solid was filtered and dried under vacuum at room temperature to obtain 4.72 g (93.6% yield) of 2-bromo-3-bromomethyl-7-phenylacetamido-3-cephem-4-carboxylic acid 1-oxide as a pale yellow solid.

1. customThe solvent was then evaporated
2. additiondiethyl ether was added
3. customthe solvent was evaporated again
4. additionDiethyl ether was added again
5. filtrationthe solid was filtered
6. customdried under vacuum at room temperature