Sulfuric Acid → tert-butyl (6R,7R)-3-[(acetyloxy)methyl]-7-amino-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

Dry dioxane was freed from peroxide by passage through a column of neutral activated alumina. To 100 ml of this solvent was added, in turn, with ice-cooling 10 ml of conc. sulfuric acid, 10.9 g of 7-ACA and 50 ml of liquid isobutylene. The mixture was sealed in a pressure bottle, stirred at 30° C. for 2 hours, poured into excess of ice-cold aqueous sodium bicarbonate solution. The solution was extracted with ethyl acetate. The combined ethyl acetate extract was washed with brine and dried over sodium sulfate. Evaporation of the filtrate under reduced pressure gave a light brown foam, 8.3 g (63%) of t-butyl-7β-amino-3-acetoxymethyl-3-cephem-4-carboxylate.

Provenance & Evidence