Acetyl chloride → HCID 131710760, compound

Participants

Reaction Steps

To a solution of acetyl chloride (8 ml.) in methylene chloride (8 ml.) was added 3-acetoxymethyl-7β-(2-hydroxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylic acid (syn-isomer) (500 mg.) in portions over ten minutes with vigorous stirring at room temperature. A gem formed, and ethyl acetate (8 ml.) was added to achieve solution. After stirring for two hours at room temperature, the mixture was added slowly to petroleum spirit (300 ml.) with vigorous stirring. The precipitate was filtered off, washed thoroughly with petroleum spirit, dissolved in chloroform (10 ml.) stirred with activated charcoal and filtered. The filtrate was added dropwise to petroleum spirit (250 ml.) with stirring. The precipitate was filtered off and dried giving the title acid, (350 mg; 62%), τ (DMSO-d6) values include -0.11 (doublet, J 8 Hz; NH), 2.2-2.6 (multiplet; aromatic protons), 7.76 (singlet; CH3. CO2N=), 7.94 (singlet; Ch3C0). Signals at τ 0.05 (doublet, J 9 Hz; NH) and 7.78 (singlet; CH3CO2 =) indicated the presence of about 30% of the anti-isomer.

Provenance & Evidence