反应详情

To a suspension of 7β-[(Z)-2-(2-t-butoxycarbonylaminothiazol-4-yl)-2-trityloxyiminoacetamido]-3-(1,2,3-triazol-4-yl) thiomethylthio-3-cephem-4-carboxylic acid diphenylmethyl ester (9.2 g: 9 mMol.) in a mixture of anisole (18 ml) and nitromethane (72 ml) is added dropwise a solution of aluminum chloride (9.6 g: 72 mMol.) in anisole (31 ml) at -30° C. After stirring for 1 hour at the same temperature, the reaction mixture is quenched with ethanol (25 ml), stirred for several minutes, diluted with 1N-hydrochloric acid (75 ml) and water (500 ml), and washed with ethyl acetate. The aqueous layer was separated, concentrated to remove the organic solvents, and passed through a column of styrene-divinylbenzene copolymer adsorbent. The product is eluted with a mixture of methanol and water (4:1) to give 7β-[(Z)-2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-3-(1,2,3-triazol-4-yl)thiomethylthio-3-cephem-4-carboxylic acid as pale yellow powder (4.19 g). Yield: 90%.

1. customthe reaction mixture is quenched with ethanol (25 ml)
2. stirringstirred for several minutes
3. additiondiluted with 1N-hydrochloric acid (75 ml) and water (500 ml)
4. washwashed with ethyl acetate
5. customThe aqueous layer was separated
6. concentrationconcentrated
7. customto remove the organic solvents
8. washThe product is eluted with a mixture of methanol and water (4:1)