反应详情

温度

0 °C

Mecuric chloride (12.37 g, 45.6 mmol) is added in one portion to a solution of (3S,4R)-1-(t-butyldimethylsilyl)-3-[(R)-1-hydroxyethyl]-4-[2,2,2-tri(methylthio)ethyl]azetidin-2-one (6.0 g, 15.2 mmol) in 250 ml of absolute methanol at 0° C. The resulting mixture (heavy white precipitate) is stirred at 0° C. for 3 min., then quenched by addition of sodium bicarbonate (8.99 g, 107 mmol). This mixture is then filtered and the solid residue is washed with additional methanol. The combined filtrate and washings are concentrated in vacuo and the residue is partitioned between ethyl acetate and saturated aqueous ammonium chloride solution. The organic phase is separated, washed with saturated aqueous ammonium chloride solution, water and brine and dried over magnesium sulfate. Removal of solvents in vacuo gives an oil which is chromatographed on a silica gel column (3:2 cyclohexane:ethyl acetate) to yield (3S,4R)-1-(t-butyldimethylsilyl) -3-[(R)-1-hydroxyethyl)]-4-carbomethoxymethyl azetidin-2-one.

1. filtrationThis mixture is then filtered
2. washthe solid residue is washed with additional methanol
3. concentrationThe combined filtrate and washings are concentrated in vacuo
4. customthe residue is partitioned between ethyl acetate and saturated aqueous ammonium chloride solution
5. customThe organic phase is separated
6. washwashed with saturated aqueous ammonium chloride solution, water and brine
7. dry with materialdried over magnesium sulfate
8. customRemoval of solvents in vacuo
9. customgives an oil which
10. customis chromatographed on a silica gel column (3:2 cyclohexane:ethyl acetate)