Ammonium Chloride → Benzyl 4-(2-hydroxyethoxy)piperidine-1-carboxylate

Temperature

0 °C

A mixture of sodium borohydride (10.1 g), calcium chloride (13.3 g), ethanol (100 mL) and THF (50 mL) was stirred at 0° C. for 30 min. After stirring, a mixture of benzyl 4-(2-ethoxy-2-oxoethoxy)piperidine-1-carboxylate (9.68 g) and THF (50 mL) was added dropwise at 0° C., and the obtained mixture was stirred at room temperature for 2 days. Saturated aqueous ammonium chloride solution was added thereto, and the insoluble material was filtered off. The filtrate was concentrated under reduced pressure. The residue was extracted with ethyl acetate, and the extract was washed with saturated brine, and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure and the residue was purified by silica gel column chromatography (ethyl acetate/hexane) to give the title compound (6.33 g).

1. stirringAfter stirring
2. additionwas added dropwise at 0° C.
3. stirringthe obtained mixture was stirred at room temperature for 2 days
4. filtrationthe insoluble material was filtered off
5. concentrationThe filtrate was concentrated under reduced pressure
6. extractionThe residue was extracted with ethyl acetate
7. washthe extract was washed with saturated brine
8. dry with materialdried over anhydrous sodium sulfate
9. customThe solvent was evaporated under reduced pressure
10. customthe residue was purified by silica gel column chromatography (ethyl acetate/hexane)

ORD record

ord-08ddfeb854374075990b9f7d08571836

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08703758B2