反应详情

To a solution of benzhydryl 7-(4-bromo-3,3-diethoxy-2-methoxyiminobutyramido)-3-vinyl-3-cephem-4-carboxylate (syn isomer) (6.5 g) in methylene chloride (60 ml) was added conc. hydrochloric acid (6 ml) at 3° to 5° C., and the mixture was stirred from under ice-cooling to at ambient temperature for 8 hours. After methylene chloride (100 ml) was added to the reaction mixture, it was heated with water and then dried over anhydrous magnesium sulfate. Removal of the solvent gave a residue, which was washed with diethyl ether to obtain benzhydryl 7-(4-bromo-2-methoxyiminoacetoacetamido)-3-vinyl-3-cephem-4-carboxylate (syn isomer) (3.5 g).

1. dry with materialdried over anhydrous magnesium sulfate
2. customRemoval of the solvent
3. customgave a residue, which
4. washwas washed with diethyl ether