Phosphorus oxychloride → HCID 131712231, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-(4-aminopyrimidin-2-yl)-2-methoxyiminoacetic acid (syn isomer) (2.32 g) and phosphoryl chloride (4.6 g) in methylene chloride (15 ml) was stirred for 30 minutes at 3° C. To the mixture was added dropwise a solution of N,N-dimethylformamide (3.0 ml) in methylene chloride (15 ml) and stirred for 40 minutes at 3° C. A solution of 4-nitrobenzyl 7-amino-3-cephem-4-carboxylate (3.02 g) and trimethylsilyl acetamide (15 g) in methylene chloride (60 ml) was cooled to -5° C. and added to the activated acid solution obtained above. The mixture was stirred for 30 minutes at 3° to 5° C. and for additional 30 minutes at ambient temperature. The solvent was evaporated to dryness and the residue was dissolved in ethyl acetate (200 ml). The solution was washed with an aqueous solution of sodium bicarbonate and water, dried over anhydrous magnesium sulfate and evaporated to dryness. The residue was washed with diethyl ether to give 4-nitrobenzyl 7-[2-(4-aminopyrimidin-2-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylate (syn isomer) (3.1 g) as a powder, mp 125°-131° C. (dec.).

Provenance & Evidence