Ethanol → HCID 178436976, compound

Participants

Reaction Steps

p-Nitrobenzyl 7-[2-(p-nitrobenzyloxycarbonylmethoxyimino)-2-{2-(2,2,2-trifluoroacetamido)thiazol-4-yl}acetamido]-3-vinylthio-3-cephem-4-carboxylate (syn isomer) (2.3 g) was hydrogenated in the presence of 5% palladium on carbon in a mixture of tetrahydrofuran (100 ml), ethanol (11.5 ml) and 0.025M phosphate buffer solution (pH 6.85) (125 ml) at ambient temperature for 5 hours under 1 atmospheric pressure of hydrogen. The catalyst was filtered off and washed with ethyl acetate and a saturated aqueous solution of sodium bicarbonate successively. The filtrate and washings were combined and adjusted to pH 8 with dilute hydrochloric acid. The aqueous layer was separated, adjusted to pH 6 with dilute hydrochloric acid and washed with ethyl acetate. The aqueous layer was adjusted to pH 2 with dilute hydrochloric acid and extracted with ethyl acetate. The extract was washed with a saturated aqueous solution of sodium chloride, dried over magnesium sulfate, concentrated in vacuo and triturated with diisopropyl ether to give 7-[2-carboxymethoxyimino-2-{2-(2,2,2-trifluoroacetamido)thiazol-4-yl}acetamido]-3-vinylthio-3-cephem-4-carboxylic acid (syn isomer) (1.05 g).

Provenance & Evidence