4-Chlorophenylacetyl chloride → (4R)-3-[(4-chlorophenyl)acetyl]-4-isopropyl-1,3-oxazolidin-2-one

Temperatur

-78 °C

To a solution of (4R)-4-isopropyl-1,3-oxazolidin-2-one (5.3 g, 41.1 mmol) in dry THF (100 mL) at −78° C. under argon, was added dropwise a 2.5M solution of n-BuLi in hexanes (17.0 mL, 42.5 mmol). After stirring at −78° C. for 15 min, (4-chlorophenyl)acetyl chloride (2.70 mL, 21.8 mmol) was added. The resulting reaction mixture was stirred at −78° C. for 30 min and 0° C. for 15 min, quenched with saturated NH4Cl (15 mL) and concentrated in vacuo. The residue was dissolved in EtOAc (200 mL) and washed with saturated Na2CO3 following by brine, dried over MgSO4, filtered and concentrated in vacuo. The crude material was purified by flash chromatography (10%–15% EtOAc/hexane) to give 6.48 g (23.1 mmol, 56%) of (4R)-3-[(4-chlorophenyl)acetyl]-4-isopropyl-1,3-oxazolidin-2-one: 1H NMR (400 MHz, CDCl3) δ 7.31–7.22 (m, 4H), 4.45–4.41 (m, 1H), 4.35–4.16 (m, 4H), 2.39–2.29 (m, 1H), 0.89 d, 3H, J=7.2 Hz), 0.80 (d, 3 H, J=7.2 Hz); ESMS m/e: 282.1 (M+H)+.

1. customThe resulting reaction mixture
2. stirringwas stirred at −78° C. for 30 min and 0° C. for 15 min
3. customquenched with saturated NH4Cl (15 mL)
4. concentrationconcentrated in vacuo
5. dissolutionThe residue was dissolved in EtOAc (200 mL)
6. washwashed with saturated Na2CO3 following by brine
7. dry with materialdried over MgSO4
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customThe crude material was purified by flash chromatography (10%–15% EtOAc/hexane)

ORD-Eintrag

ord-ef014e97fb384b4f83a5f1b2ea65fea2

Quelldatensatz

uspto-grants-2007_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07199135B2