反应详情

A solution of 1-tert-butyl 3-methyl 5-{[(benzyloxy)carbonyl](2-methylpropyl)amino}piperidine-1,3-dicarboxylate (13.0 g) in THF (100 ml) was added to a solution of calcium chloride (6.5 g) and sodium borohydride (4.5 g) in ethanol (100 ml) under ice-cooling, and the mixture was stirred at room temperature for 2 hr. The reaction mixture was adjusted to pH 4 with 10% aqueous citric acid solution, and concentrated under reduced pressure to a half volume. The residue was extracted with ethyl acetate. The extract was washed with saturated brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure. The residue was subjected to silica gel column chromatography, and the fraction eluted with ethyl acetate-hexane (5:95-80:20) was concentrated under reduced pressure to give the object compound (8.04 g).

1. temperaturecooling
2. concentrationconcentrated under reduced pressure to a half volume
3. extractionThe residue was extracted with ethyl acetate
4. washThe extract was washed with saturated brine
5. dry with materialdried over anhydrous magnesium sulfate
6. customThe solvent was evaporated under reduced pressure
7. washthe fraction eluted with ethyl acetate-hexane (5:95-80:20)
8. concentrationwas concentrated under reduced pressure