Sodium Chloride → HCID 86738836, compound

Participants

Reaction Conditions

Reaction Steps

Acetic anhydride (22.5 ml.) and boron trifluoride etherate (7.5 ml.) were added to a stirred solution of 7-(2-methoxyimino-3-oxo-4-bromobutyramido)-3-hydroxycepham-4-carboxylic acid (syn isomer 31.8 g.) in dry tetrahydrofuran (150 ml.) at room temperature, and stirred at the same temperature for 30 minutes and at 50° C. for an hour. To the resultant solution was added a saturated aqueous solution of sodium chloride (100 ml.) and stirred for 30 minutes. Ethyl acetate (150 ml.) was added to the solution, and the ethyl acetate layer was separated, and washed with a saturated aqueous solution of sodium chloride. The aqueous layer was extracted with ethyl acetate (100 ml.). The ethyl acetate layer and the extract were combined, treated with activated charcoal and evaporated. After adding diisopropyl ether (500 ml.) to the residue, the solvent was decanted. The residue was pulverized with diisopropyl ether, and the precipitates were collected by filtration and dried to give 7-(2-methoxyimino-3-oxo-4-bromobutyramido)-3-acetoxycepham-4 -carboxylic acid (syn isomer, 35.3 g.)

Provenance & Evidence