(R)-4-Benzyl-2-oxazolidinone → (R)-4-Benzyl-3-pent-4-enoyloxazolidin-2-one

Temperature

-78 °C

To a cooled (−78° C.) solution of (R)-4-benzyloxazolidin-2-one (2.242 g, 12.652 mmol) in 30 mL of THF, was added n-BuLi (5.6 mL, 13.917 mmol, 2.5 M in hexane). The resulting mixture was stirred at −78° C. under N2 for 15 min and then pent-4-enoyl chloride (1.500 g, 12.652 mmol) was added. After stirring at −78° C. for 1 h the reaction was warmed to room temperature under N2 and stirred overnight. The reaction mixture was quenched with 60 mL of aqueous NH4Cl solution and extracted with dichloromethane (50 mL×3). The combined organic extracts were dried, filtered, and concentrated under reduced pressure. The product was isolated by Flash column chromatography (silica gel) eluting with 0-30% ethyl acetate/hexanes to give the title compound as colorless oil (2.146 g, 65% yield). GC-MS: tR=4.2 min; m/z 259 (M+).

1. stirringAfter stirring at −78° C. for 1 h the reaction
2. temperaturewas warmed to room temperature under N2
3. stirringstirred overnight
4. customThe reaction mixture was quenched with 60 mL of aqueous NH4Cl solution
5. extractionextracted with dichloromethane (50 mL×3)
6. customThe combined organic extracts were dried
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customThe product was isolated by Flash column chromatography (silica gel)
10. washeluting with 0-30% ethyl acetate/hexanes

ORD record

ord-c9618cf1ec7e4c5aac3c2f637e3dbeff

Source dataset

uspto-grants-2010_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07807720B2