2,2,2-Trichloroethyl 2-methyl-2,3-methylene-6-(2-phenylacetamido)penam-3-carboxylate → 2,2,2-Trichloroethyl 2-methyl-7-(2-phenylacetamido)-2-cephem-4-carboxylate

Participants

Reaction Steps

Titanium tetrachloride (0.19 g.) was added to a solution of 2,2,2-trichloroethyl 2-methyl-2,3-methylene-6-(2-phenylacetamido)penam-3-carboxylate (0.46 g.) in dried dichloromethane (5 ml.) and the mixture was stirred for 2.5 hours. After the reaction, the reaction mixture was washed in turn with 2% hydrochloric acid three times, a saturated sodium bicarbonate aqueous solution and a saturated sodium chloride aqueous solution and then dried over magnesium sulfate. After the solvent was distilled off the residue (0.43 g.) was purified by column chromatography on silica gel (10 g.) using chloroform as developing solvent to give 2,2,2-trichloroethyl 2-methyl-7-(2-phenylacetamido)-2-cephem-4-carboxylate (0.1 g.) mp 136° to 137° C.

Provenance & Evidence