Hydrochloric Acid → (R)-4-Benzyl-2-oxazolidinone

HRID 58952Notes

Reaction equation

[CH2:1]([C@@H:8]1[CH2:12][O:11][C:10](=[O:13])[N:9]1[C:14](=[O:39])[C@H:15]([CH2:31][CH2:32][C:33]1[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=1)[C@@H:16]([OH:30])[C@@H:17]([O:19][Si](C(C)C)(C(C)C)C(C)C)[CH3:18])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.Cl>CCO>[OH:30][C@H:16]1[C@H:17]([CH3:18])[O:19][C:14](=[O:39])[C@@H:15]1[CH2:31][CH2:32][C:33]1[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=1.[CH2:1]([C@@H:8]1[CH2:12][O:11][C:10](=[O:13])[NH:9]1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

Conditions

Temperature: 80 °C

Procedure

To a solution of (R)-4-benzyl-3-((2R,3R,4S)-3-hydroxy-2-phenethyl-4-((triisopropylsilyl)oxy)pentanoyl)-oxazolidin-2-one (2.52 g, 4.55 mmol) in EtOH (18 mL) was added 1 N HCl (2 mL, 2 mmol) and the mixture heated to 80° C. for a 3 h. The solution was concentrated in vacuo, and the residue was dissolved in CH2Cl2, loaded onto a pre-packed Celite® cartridge, and purified by flash chromatography (SiO2, 0→100% EtOAc/hexanes) gave (3R,4R,5S)-4-hydroxy-5-methyl-3-phenethyldihydrofuran-2(3H)-one (840 mg, 3.81 mmol, 84% yield) and (R)-4-benzyloxazolidin-2-one (710 mg, 4.01 mmol, 88% yield). The title product was obtained as a colorless, amorphous solid: 1H NMR (600 MHz, CDCl3) δ 7.33-7.28 (m, 2H), 7.25-7.19 (m, 3H), 4.20-4.13 (m, 1H), 3.80 (dd, J=8.9, 7.3 Hz, 1H), 2.96-2.88 (m, 1H), 2.86-2.79 (m, 1H), 2.59-2.52 (m, 1H), 2.28-2.17 (m, 2H), 1.97-1.88 (m, 1H), 1.43 (d, J=6.3 Hz, 3H); 13C NMR (151 MHz, CDCl3) δ 175.91, 140.94, 128.64, 128.51, 126.34, 79.89, 79.36, 47.98, 32.81, 30.25, 18.19; ESIMS m/z 221 ([M+H]+).

Workup

concentrationThe solution was concentrated in vacuo
dissolutionthe residue was dissolved in CH2Cl2
custompurified by flash chromatography (SiO2, 0→100% EtOAc/hexanes)

Sources & evidence

ORD record: ord-3c448d5cd8a3408eb8cbe718054f94aa
Source dataset: uspto-grants-2016_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09439422B2

Reaction notes

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