反应详情

A solution of 5.6 g of t-butyl 2-bromo-3-bromomethyl-7-phenylacetamido-3-cephem-4-carboxylate-1-oxide in 40 ml of trifluoroacetic acid was stirred for 15 minutes at room temperature and the solvent was removed under vacuo. Ether was added to the residue, whereafter the evaporation to dryness was repeated. After addition of ether, the crystals were collected by filtration to obtain 4.72 g of 2-bromo-3-bromomethyl-7-phenylacetamido-3-cephem-4-carboxylic acid-1-oxide as a slightly yellow solid having the following characteristics:

1. customthe solvent was removed under vacuo
2. additionEther was added to the residue, whereafter the evaporation to dryness
3. additionAfter addition of ether
4. filtrationthe crystals were collected by filtration