反应详情

To a solution of (2S,4R)-1-benzyloxycarbonyl-2-hydroxymethyl-4-methanesulfonyloxypyrrolidine (100 g) and ethyl bromoacetate (100 ml) in tetrahydrofuran (500 ml) was added a solution of potassium t-butoxide (100 g) in tetrahydrofuran (500 ml) in a nitrogen stream at -15°~-10° C. for 2 hours and the mixture was stirred at ambient temperature for 3 hours. To the reaction mixture was added 2N aqueous sodium hydroxide (500 ml) at 0°-10° C. and the mixture was stirred at ambient temperature for 18 hours. The organic solvent was evaporated under reduced pressure to give an aqueous solution. To the aqueous solution was added water (500 ml), adjusted to pH 10 with 4N aqueous sodium hydroxide and washed with ethyl acetate (500 ml×2). The aqueous solution was adjusted to pH 4 with concentrated hydrochloric acid and extracted with ethyl acetate (300 ml×2). The organic layer was washed with brine (300 ml), dried over magnesium sulfate and concentrated under reduced pressure to give (2S,4R)-1-benzyloxycarbonyl-2-(carboxymethyloxymethyl)-4-methanesulfonyloxypyrrolidine (94.0 g).

1. stirringthe mixture was stirred at ambient temperature for 18 hours
2. customThe organic solvent was evaporated under reduced pressure
3. customto give an aqueous solution
4. washwashed with ethyl acetate (500 ml×2)
5. extractionextracted with ethyl acetate (300 ml×2)
6. washThe organic layer was washed with brine (300 ml)
7. dry with materialdried over magnesium sulfate
8. concentrationconcentrated under reduced pressure