Dimethylformamide → benzhydryl 7-(2-phenylacetamido)-3-[2-(2-propynyl)-2H-tetrazol-5-yl]thiomethyl-3-cephem-4-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of benzhydryl 7-(2-phenylacetamido)-3-[2-(2-propynyl)-2H-tetrazol-5-yl]thiomethyl-3-cephem-4-carboxylate-1-oxide (16.0 g) and dry N,N-dimethylformamide (160 ml) was cooled to -30° C. and thereto was added phosphorus trichloride (6.7 g). The resulting solution was stirred for 50 minutes at -30° C. The reaction mixture was allowed to warm to ambient temperature, added to water (200 ml) and then extracted with ethyl acetate (×3). The extracts were combined, washed successively with a saturated aqueous solution of sodium bicarbonate (×3) and water (×3), dried over magnesium sulfate, treated with activated charcoal and then evaporated. The residue was pulverized in a mixture of isopropyl ether and n-hexane, collected by filtration, washed with n-hexane and then dried to give benzhydryl 7-(2-phenylacetamido)-3-[2-(2-propynyl)-2H-tetrazol-5-yl]thiomethyl-3-cephem-4-carboxylate (14.33 g).

Provenance & Evidence