(4R,5S)-(+)-4-Methyl-5-phenyl-2-oxazolidinone → (4R,5S)-3-[3-(4-Chlorophenyl)-propionyl]-4-methyl-5-phenyl-oxazolidin-2-one

HRID 1192344Notes

Reaction equation

[Li]CCCC.[CH3:6][C@@H:7]1[C@H:11]([C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[O:10][C:9](=[O:18])[NH:8]1.[Cl:19][C:20]1[CH:25]=[CH:24][C:23]([CH2:26][CH2:27][C:28](Cl)=[O:29])=[CH:22][CH:21]=1>C1COCC1>[Cl:19][C:20]1[CH:21]=[CH:22][C:23]([CH2:26][CH2:27][C:28]([N:8]2[C@H:7]([CH3:6])[C@H:11]([C:12]3[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=3)[O:10][C:9]2=[O:18])=[O:29])=[CH:24][CH:25]=1

Participants

Conditions

Temperature: -78 °C

Procedure

nBuLi (1.6M in hexanes, 20 mL, 32 mmol) was added to a stirred solution of (4R,5S)-4-Methyl-5-phenyl-oxazolidin-2-one (5.2 g, 29 mmol) in THF (60 mL) at −78 C under N2. The solution was stirred at −78° C. for 10 mL and then 3-(4-Chlorophenyl)-propionyl chloride (6.0 g, 29 mmol) was added and the solution allowed to warm to room temperature over 1 hour. The solution was quenched with saturated aqueous NH4Cl, extracted into DCM (2×200 mL), dried over Na2SO4 and concentrated in vacuo. The product was purified by column chromatography on silica (50% EtOAc/hexanes) to give (4R,5S)-3-[3-(4-Chlorophenyl)-propionyl]-4-methyl-5-phenyl-oxazolidin-2-one (4.8 g, 48%.) 1H NMR (CDCl3, 400 MHz) δ 7.44-7.35 (3H, m), 7.30-7.24 (4H, m), 7.19 (2H, d, J 8.0 Hz), 5.64 (1H, d, J 7.4 Hz), 4.77-4.71 (1H, m), 3.34-3.17 (2H, m), 2.98 (2H, t, J 7.7 Hz), 0.88 (3H, d, J 6.7 Hz.)

Workup

temperatureto warm to room temperature over 1 hour
customThe solution was quenched with saturated aqueous NH4Cl
extractionextracted into DCM (2×200 mL)
dry with materialdried over Na2SO4
concentrationconcentrated in vacuo
customThe product was purified by column chromatography on silica (50% EtOAc/hexanes)

Sources & evidence

ORD record: ord-7677660d49a248319120b33e19786fb1
Source dataset: uspto-grants-2014_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08680114B2

Reaction notes

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