Allyl bromide → 4-Benzyl-3-(2-cyclohexyl-pent-4-enoyl)-oxazolidin-2-one

To a solution of 4-benzyl-3-(2-cyclohexyl-acetyl)-oxazolidin-2-one (16.0 g, 53 mmol) in anhydrous tetrahydrofuran at −78° C. was added a 1.0 M solution of sodium bis(trimethylsilyl)-amide (79.0 mL, 79 mmol), and the reaction mixture was stirred for 1 h. To the reaction mixture was then added allyl bromide (18.4 mL, 213 mmol), and the temperature was raised to −45° C. The reaction mixture was stirred at this temperature for 3 h. The reaction was quenched with aqueous saturated NH4Cl solution, and the resulting mixture was warmed to room temperature. The reaction mixture was extracted with ethyl acetate, and the combined extracts were washed with brine. The organic layers were dried (MgSO4) and concentrated in vacuo to yield a residue that was purified by silica gel column chromatography (5:1 hexanes:ethyl acetate) to yield (4-benzyl-3-(2-cyclohexyl-pent-4-enoyl)-oxazolidin-2-one) as a thick liquid that became a solid upon storage.

1. stirringThe reaction mixture was stirred at this temperature for 3 h
2. customThe reaction was quenched with aqueous saturated NH4Cl solution
3. extractionThe reaction mixture was extracted with ethyl acetate
4. washthe combined extracts were washed with brine
5. dry with materialThe organic layers were dried (MgSO4)
6. concentrationconcentrated in vacuo
7. customto yield a residue that
8. customwas purified by silica gel column chromatography (5:1 hexanes:ethyl acetate)

ORD record

ord-cd5345cf22f84f82b7a580e1d860095d

Source dataset

uspto-grants-2010_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07776882B2