反应详情

温度

0 °C

To a solution of sodium (518 mg, 22.5 mmole) in methanol (100 ml) was added at -10° C. (R)-1-methyl-2-(p-nitrobenzyloxycarbonylamino)ethanethiol (6.61 g, 23.1 mmole). The mixture was stirred for 5 minutes, and then carbon disulphide (1.76 g, 23.1 mmole) was added and stirring was continued for a further 10 minutes. (3R, 4R)-4-acetoxy-3-[(R)-1-t-butyldimethylsilyloxyethyl]azetidin-2-one (6.46 g, 22.5 mmole) was then added at the same temperature, after which the bath temperature was raised to 0° C. over about 1 hour. About 300 mg of acetic acid was then added, and the reaction mixture was diluted with ethyl acetate and washed with a saturated aqueous solution of sodium chloride. After the solution had been dried, the solvent was distilled off under reduced pressure and the residue was purified through column chromatography (200 g of silica gel), eluted with a 10% v/v solution of ethyl acetate in benzene, affording the desired compound (10.8 g, 84%) in the form of a yellow oil.

1. stirringstirring
2. waitwas continued for a further 10 minutes
3. washwashed with a saturated aqueous solution of sodium chloride
4. customAfter the solution had been dried
5. distillationthe solvent was distilled off under reduced pressure
6. customthe residue was purified through column chromatography (200 g of silica gel)
7. washeluted with a 10% v/v solution of ethyl acetate in benzene