反应详情

At 0°, 24 ml of 1N NaOH, 820 mg of tetrabutylammonium bisulphate and 1 ml of chloroformic acid allyl ester are added to a solution of 2 g of (3S,4S)-1-(p-methoxybenzyl)-3-[(1R)-1-hydroxyethyl)-4-tert.-butoxycarbonyl-2-azetidinone in 24 ml of methylene chloride and the whole is stirred vigorously. After a reaction time of 20 and 40 minutes, further portions (each of 1 ml) of chloroformic acid allyl ester are added. The reaction mixture is diluted with methylene chloride, the aqueous phase is separated off and the organic layer is washed in succession with 5% aqueous citric acid and 8% aqueous NaHCO3 solution and then dried and concentrated by evaporation. After purifying by chromatography, the pure, amorphous title compound is obtained.

1. customthe aqueous phase is separated off
2. washthe organic layer is washed in succession with 5% aqueous citric acid and 8% aqueous NaHCO3 solution
3. customdried
4. concentrationconcentrated by evaporation
5. customAfter purifying by chromatography