反应详情

The above-mentioned tert-butyl methyl-{(3S)-3-methyl-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidin-3-yl}carbamate (3.94 g, 11.9 mmol) was dissolved in tetrahydrofuran (120 ml), then with cooling with ice, borane/tetrahydrofuran complex (29.6 ml 35.6 mmol) was added, followed by stirring at room temperature for 17 hours. Ethanol (36 ml), triethylamine (12 ml) and water (12 ml) were added to the reaction liquid, followed by stirring in an oil bath at 80° C. for 2 hours. The reaction liquid was concentrated under reduced pressure, partitioned with ethyl acetate and water, and the aqueous layer was extracted with ethyl acetate. The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, the insoluble matter was separated by filtration, and the residue obtained by concentration was purified by silica gel column chromatography (eluent, n-hexane:ethyl acetate=1:1, v/v) to obtain tert-butyl methyl-{(3S)-3-methyl-1-[(1R)-1-phenylethyl]pyrrolidin-3-yl}carbamate (2.44 g, 65%) as a colorless oily substance.

1. temperaturewith cooling with ice, borane/tetrahydrofuran complex (29.6 ml 35.6 mmol)
2. additionwas added
3. stirringby stirring in an oil bath at 80° C. for 2 hours
4. customThe reaction liquid
5. concentrationwas concentrated under reduced pressure
6. custompartitioned with ethyl acetate and water
7. extractionthe aqueous layer was extracted with ethyl acetate
8. washThe organic layer was washed with saturated brine
9. dry with materialdried over anhydrous sodium sulfate
10. customthe insoluble matter was separated by filtration
11. customthe residue obtained by concentration
12. customwas purified by silica gel column chromatography (eluent, n-hexane