反应详情

Phosphorus trichloride (0.5 ml.) was dropwise added under ice-cooling to a solution of 2,2,2-trichloroethyl 2-methyl-7-(2-phenylacetamido)-3-cephem-4-carboxylate-1-oxide (0.72 g.) in dimethylformamide (5 ml.) and the mixture was stirred for 1 hour at the same temperature. After the reaction, the reaction mixture was poured into a mixture of ethyl acetate (40 ml.) and ice-water (40 ml.), and the ethyl acetate layer was separated. The aqueous layer was further extracted with ethyl acetate (10 ml.), and the ethyl acetate layer was combined. The combined solution was washed in turn with 5% hydrochloric acid, a sodium bicarbonate aqueous solution and a saturated sodium chloride aqueous solution, and dried over magnesium sulfate. The dried solution was treated with activated charcoal and the solvent was distilled off. The residue was crystallized with a small amount of ether to give 2,2,2-trichloroethyl 2-methyl-7-(2-phenylacetamido)-3-cephem-4-carboxylate (0.43 g.), mp 175° to 178° C.

1. customAfter the reaction
2. customthe ethyl acetate layer was separated
3. extractionThe aqueous layer was further extracted with ethyl acetate (10 ml.)
4. washThe combined solution was washed in turn with 5% hydrochloric acid
5. dry with materiala sodium bicarbonate aqueous solution and a saturated sodium chloride aqueous solution, and dried over magnesium sulfate
6. additionThe dried solution was treated with activated charcoal
7. distillationthe solvent was distilled off
8. customThe residue was crystallized with a small amount of ether