反应详情

To a suspension of sodium borohydride (0.42 g) in tetrahydrofuran (20 ml) was dropwise added boron trifluoride etherate (5.25 ml) under ice-cooling and the mixture was stirred at the same temperature for 10 minutes. To this solution was added a solution of (2S,4R)-2-(2,4-dioxoimidazolidin-1-yl)methyl-4-hydroxy-1-(4-nitrobenzyloxycarbonyl)pyrrolidine (2.1 g) in tetrahydrofuran (10 ml) under ice-cooling and the mixture was stirred at ambient temperature for 3 hours. To the reaction mixture was dropwise added methanol (5 ml) and the mixture was filtered off. The filtrate was evaporated in vacuo. The resulting residue was dissolved in methanol (30 ml) and 1.7M hydrogen chloride-methanol solution (6 ml) and the solution was allowed to stand overnight at ambient temperature. The reaction mixture was evaporated in vacuo and dissolved in ethyl acetate (60 ml). The solution was washed successively with saturated aqueous sodium hydrogen carbonate and saturated aqueous sodium chloride, dried over magnesium sulfate, and evaporated in vacuo to give precipitates. The precipitates were washed with ethyl acetate (20 ml) and air-dried to give (2S,4R)-4-hydroxy-1-(4-nitrobenzyloxycarbonyl)-2-(2-oxoimidazolidin-1-yl)methyl pyrrolidine (1.39 g).

1. temperaturecooling
2. temperaturecooling
3. stirringthe mixture was stirred at ambient temperature for 3 hours
4. filtrationthe mixture was filtered off
5. customThe filtrate was evaporated in vacuo
6. dissolutionThe resulting residue was dissolved in methanol (30 ml)
7. waitto stand overnight at ambient temperature
8. customThe reaction mixture was evaporated in vacuo
9. dissolutiondissolved in ethyl acetate (60 ml)
10. washThe solution was washed successively with saturated aqueous sodium hydrogen carbonate and saturated aqueous sodium chloride
11. dry with materialdried over magnesium sulfate
12. customevaporated in vacuo
13. customto give
14. customprecipitates
15. washThe precipitates were washed with ethyl acetate (20 ml)
16. customair-dried