反应详情

To a solution of 1 g. of 7-cyanomethylthioacetamido-3-methoxy-3-cephem-4-carboxylic acid p-nitrobenzyl ester in 60 ml. of tetrahydrofuran and 100 ml. of methanol containing 5 drops of 1N hydrochloric acid is added 1 g. of prereduced 5% palladium on charcoal in 40 ml. of ethanol. The mixture is hydrogenated for 3 hours at room temperature at 50 psi. The catalyst is filtered and washed with tetrahydrofuran and water. The filtrate and washings are combined, solvent is removed in vacuo and the residue is taken up in an ethyl acetate water mixture. The pH of the aqueous layer is adjusted to 7.5 and the ethyl acetate is removed. Fresh ethyl acetate is added and the pH is adjusted to 2.5. The ethyl acetate layer is removed, washed with water and dried over sodium sulfate. Removal of the solvent in vacuo yields the product 7-cyanomethylthioacetamido-3-methoxy-3-cephem-4-carboxylic acid as a foam.

1. filtrationThe catalyst is filtered
2. washwashed with tetrahydrofuran and water
3. customsolvent is removed in vacuo
4. customthe ethyl acetate is removed
5. additionFresh ethyl acetate is added
6. customThe ethyl acetate layer is removed
7. washwashed with water
8. dry with materialdried over sodium sulfate
9. customRemoval of the solvent in vacuo