Bromoacetyl bromide → 2-Oxazolidinone, 3-(bromoacetyl)-4-(phenylmethyl)-, (4R)-
Reaction equation
[CH2:1]1[O:6][C:4](=[O:5])[NH:3][C@@H:2]1[CH2:7][C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1.[Li]CCCC.[Br:19][CH2:20][C:21](Br)=[O:22].CCOC(C)=O.CCCCCC>C1COCC1.C(OCC)(=O)C>[CH2:7]([C@@H:2]1[CH2:1][O:6][C:4](=[O:5])[N:3]1[C:21](=[O:22])[CH2:20][Br:19])[C:8]1[CH:9]=[CH:10][CH:11]=[CH:12][CH:13]=1Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 2
Conditions
- Temperature
- -78 °C
Procedure
To a solution of R-(−)-4-benzyl-2-oxazolidinone (15.0 g, 84.65 mmol) in THF (200 mL) was added nBuLi (2.5M in hexanes, 34 mL, 84.65 mmol) dropwise at −78° C. The solution was stirred at −78° C. for 30 min and then bromo acetyl bromide (18.65 g, 7.8 nL, 124.15 mmol) was added. The solution was allowed to warm to 25° C. overnight (19 h). An aliquot was taken and TLC (1:2 EtOAc-hexane) indicated that reaction was complete. It was diluted in ethyl acetate (200 mL) and the organic layer was washed with saturated aqueous NaRCO3 (2×50 mL). The organic layer was dried over MgSO4, filtered and concentrated to obtain a crude brown oil (24.6 g). The crude product was purified by flash chromatography, eluent: 1:4 EtOAc-hexane, to furnish (4R)-4-benzyl-3-(bromoacetyl)-1,3-oxazolidin-2-one as a colorless oil (19.9 g, 79.6%). Mass Spectrum (+ESI): 300, 299 (M+H)+.
Workup
- temperatureto warm to 25° C. overnight (19 h)
- washthe organic layer was washed with saturated aqueous NaRCO3 (2×50 mL)
- dry with materialThe organic layer was dried over MgSO4
- filtrationfiltered
- concentrationconcentrated
- customto obtain a crude brown oil (24.6 g)
- customThe crude product was purified by flash chromatography, eluent
Sources & evidence
- ORD record
- ord-325f74f8e9d04f7d93d714c02ce4e863
- Source dataset
- uspto-grants-2007_11
- Patent number
- US07300951B2
Reaction notes
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