Diketene → HCID 131714995, compound

Participants

Reaction Steps

To a solution of diketene (1.01 g) in methylene chloride (15 ml) was dropwise added bromine (1.53 g) at -20° C., and the mixture was stirred at the same temperature for 20 minutes and added to a solution of benzhydryl 7-amino-3-[(E)-2-chlorovinyl]-3-cephem-4-carboxylate (3.42 g) and trimethylsilylacetamide (5.3 g) in ethyl acetate (40 ml) at the same temperature. The reaction mixture was stirred at -10° to -15° C. for 10 minutes, poured into water and extracted with ethyl acetate. The extract was washed with 10% aqueous solution of sodium chloride and dried over magnesium sulfate. The solvent was evaporated under reduced pressure and the residue was triturated with diisopropyl ether and collected by filtration to give benzhydryl 7-(4-bromo-3-oxobutyramido)-3-[(E)-2-chlorovinyl]-3-cephem-4-carboxylate (4.8 g).

Provenance & Evidence