Reaktion #316702

Reaktionsgleichung

sodium hydrogencarbonate

benzyloxycarbonyl chloride

tert-butyl(3R)-4-hydroxy-3-methyl-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylate

hydrochloric acid

→

title compound

Ausbeute 91.1%

tert-Butyl(3R)-1-benzyloxycarbonyl-4-hydroxy-3-methylpyrrolidine-3-carboxylate

Ausbeute 91.1%

Lösungsmittel

diethylether

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   EinengenAfter concentrating the reaction mixture under reduced pressure
2. 2
   workup.DISSOLUTIONdissolving the residue in ethanol (50 mL)
3. 3
   workup.ADDITION10% palladium-carbon catalyst (200 mg) was added
4. 4
   workup.STIRRINGthe suspension was stirred in an oil bath at 50° C. for 14 hours in hydrogen atmosphere
5. 5
   FiltrationAfter filtering the reaction mixture
6. 6
   Einengenthe filtrate was concentrated
7. 7
   workup.ADDITIONwas added in an ice bath
8. 8
   workup.STIRRINGThe mixture was stirred at room temperature for 3 hours
9. 9
   Extraktionthe reaction mixture was extracted with ethyl acetate (100 mL×2)
10. 10
    WaschenThe organic layer was washed with saturated aqueous solution of sodium chloride (20 mL)
11. 11
    Trocknendried with anhydrous sodium sulfate
12. 12
    SonstigeThe solvent was removed by distillation under reduced pressure
13. 13
    Sonstigethe residue was purified by silica gel column chromatography (hexane:ethyl acetate=2:1→1:2)

Vorschrift

To a solution of tert-butyl(3R)-4-hydroxy-3-methyl-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylate (2.00 g, 6.55 mmol) in ethanol (10 mL), 1N hydrochloric acid (6.88 mL, 6.88 mmol) was added at room temperature, and the mixture was stirred for 10 minutes. After concentrating the reaction mixture under reduced pressure and dissolving the residue in ethanol (50 mL), 10% palladium-carbon catalyst (200 mg) was added, and the suspension was stirred in an oil bath at 50° C. for 14 hours in hydrogen atmosphere. After filtering the reaction mixture, the filtrate was concentrated, and the diethylether (30 mL) and saturated sodium hydrogencarbonate (30 mL) were added to the residue, and benzyloxycarbonyl chloride (982 μl, 6.88 mmol) was added in an ice bath. The mixture was stirred at room temperature for 3 hours, and the reaction mixture was extracted with ethyl acetate (100 mL×2). The organic layer was washed with saturated aqueous solution of sodium chloride (20 mL), and dried with anhydrous sodium sulfate. The solvent was removed by distillation under reduced pressure and the residue was purified by silica gel column chromatography (hexane:ethyl acetate=2:1→1:2) to obtain 2.00 g (91.1%) of the title compound as a colorless oily substance.

Quelle