反应详情

In ethanol (0.6 ml) is dissolved 2,2,2-trichloroethyl 7-hydroxyimino-3-methyl-3-cephem-4-carboxylate (100 mg) and under ice-cooling, a solution of borane-pyridine complex (102 mg) in ethanol (0.7 ml) is added. Then, a 2 N-methanolic solution of hydrogen chloride (0.6 ml) is added dropwise in a nitrogen stream and the mixture is stirred at the same temperature for 3 hours. The mixture is further stirred at room temperature for an hour, after which time it is diluted with ethyl acetate, washed with water and aqueous sodium chloride in that order, dried over magnesium sulfate and concentrated under reduced pressure. The oily residue is subjected to silica gel (4.5 g) column chromatography and elution is carried out with ethyl acetate-hexane to give 2,2,2-trichloroethyl 7 β-hydroxyamino-3-methyl-3-cephem-4-carboxylate (79 mg) as an amorphous solid.

1. temperatureunder ice-cooling
2. stirringThe mixture is further stirred at room temperature for an hour
3. washwashed with water and aqueous sodium chloride in that order
4. dry with materialdried over magnesium sulfate
5. concentrationconcentrated under reduced pressure
6. washThe oily residue is subjected to silica gel (4.5 g) column chromatography and elution