4-Methylmorpholine → Tert-butyl (s)-(1-hydroxypent-4-en-2-yl)carbamate

Temperature

-15 °C

N-methylmorpholine (15.25 ml) and ethyl chloroformate (12.60 ml) were added to a solution of (S)-2-((tert-butoxycarbonyl)amino)pent-4-enoic acid (25.0 g) in THF (250 ml) at −15° C. After stirring the mixture at −15° C. for 15 minutes, the generated insoluble matter was filtered off. A solution of sodium borohydride (3.23 g) in water (32 ml) was added to the filtrate at −15° C., and the mixture was stirred at −15° C. for 1 hour. A saturated aqueous ammonium chloride solution was added thereto, and the mixture was stirred at room temperature for 30 minutes. Ethyl acetate was added thereto to separate the organic layer. The organic layer was washed with a 0.5 N aqueous potassium hydrogensulfate solution, water, a 0.5 N aqueous sodium hydroxide solution, and a saturated sodium chloride solution; and dried over anhydrous sodium sulfate. The solvent was then distilled off under reduced pressure. The resulting residue was purified by silica gel column chromatography (developing solvent: hexane/ethyl acetate) to obtain the title compound as a light-yellow, oily substance (11.93 g).

1. filtrationthe generated insoluble matter was filtered off
2. additionA solution of sodium borohydride (3.23 g) in water (32 ml) was added to the filtrate at −15° C.
3. stirringthe mixture was stirred at −15° C. for 1 hour
4. additionA saturated aqueous ammonium chloride solution was added
5. stirringthe mixture was stirred at room temperature for 30 minutes
6. additionEthyl acetate was added
7. customto separate the organic layer
8. washThe organic layer was washed with a 0.5 N aqueous potassium hydrogensulfate solution, water
9. dry with materialand dried over anhydrous sodium sulfate
10. distillationThe solvent was then distilled off under reduced pressure
11. customThe resulting residue was purified by silica gel column chromatography (developing solvent: hexane/ethyl acetate)

ORD record

ord-c5ff72dd60d7417e812ee794c8e46959

Source dataset

uspto-grants-2014_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08889666B2