Pivaloyl chloride → (4S)-4-benzyl-3-(2-isopropoxyacetyl)oxazolidin-2-one

Temperatur

-15 °C

A tetrahydrofuran (6 L) solution of 140 g of 2-isopropoxyacetic acid and 540 mL of triethylamine was cooled to −20° C., to which a tetrahydrofuran (100 mL) solution of 145 g of 2,2-dimethylpropanoyl chloride was added dropwise, followed by stirring the reaction mixture at −10 to −20° C. for 3 hours. The reaction mixture was cooled to −30° C., to which 80 g of anhydrous lithium chloride and then 225 g of (4S)-4-benzyl-1,3-oxazolidin-2-one was added, followed by stirring the reaction mixture overnight at room temperature. The reaction mixture was filtered and subjected to vacuum concentration. The residue was dissolved in 3 L of ethyl acetate, washed with a saturated sodium bicarbonate aqueous solution (1.5 L), and dried with anhydrous magnesium sulfate. The solvent was distilled off under a reduced pressure, and the residue was purified using silica gel column chromatography to obtain 196 g of the title compound in the form of colorless oily matter from a hexane-ethyl acetate (5:1→2:1)-eluted fraction.

1. additionwas added dropwise
2. stirringby stirring the reaction mixture overnight at room temperature
3. filtrationThe reaction mixture was filtered
4. concentrationsubjected to vacuum concentration
5. dissolutionThe residue was dissolved in 3 L of ethyl acetate
6. washwashed with a saturated sodium bicarbonate aqueous solution (1.5 L)
7. dry with materialdried with anhydrous magnesium sulfate
8. distillationThe solvent was distilled off under a reduced pressure
9. customthe residue was purified

ORD-Eintrag

ord-70b6a14807564feb9c8cb9a9bef5d675

Quelldatensatz

uspto-grants-2010_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07816405B2