Butyryl chloride → (4S)-3-Butanoyl-4-(propan-2-yl)-1,3-oxazolidin-2-one
Reaction equation
[CH3:1][CH:2]([C@H:4]1[CH2:8][O:7][C:6](=[O:9])[NH:5]1)[CH3:3].[Li]CCCC.[C:15](Cl)(=[O:19])[CH2:16][CH2:17][CH3:18].C([O-])([O-])=O.[K+].[K+]>C1COCC1>[O:19]=[C:15]([N:5]1[C@@H:4]([CH:2]([CH3:3])[CH3:1])[CH2:8][O:7][C:6]1=[O:9])[CH2:16][CH2:17][CH3:18]Participants
Conditions
- Temperature
- 0 °C
Procedure
A mechanically stirred, cooled (-78° C.) solution of the oxazolidinone of Step 5 (32.3 g, 250 mmol) in anhydrous THF (830 mL) was metalated with 163 mL (1.6M in hexane, 261 mmol) of n-BuLi and treated with freshly distilled butanoyl chloride (28.1 mL, 271 mmol). The reaction mixture was warmed to 0° C. and stirred for 0.5 h. Excess acid chloride was hydrolyzed by the addition of 1M aqueous K2CO3 (165 mL) followed by stirring the resultant two-phase mixture for 1 h at r.t. Volatiles were removed in vacuo and the product was extracted into CH2Cl2 (3×). The combined organic extracts were successively washed with H2O and brine, dried over MgSO4 and concentrated to give the title compound as a pale yellow oil (52.1 g, quantative). A portion of this crude product was purified by flash chromatography on silica with EtOAc:hexane 1:4 to give a colorless liquid.
Workup
- stirringstirred for 0.5 h
- customVolatiles were removed in vacuo
- extractionthe product was extracted into CH2Cl2 (3×)
- washThe combined organic extracts were successively washed with H2O and brine
- dry with materialdried over MgSO4
- concentrationconcentrated
Sources & evidence
- ORD record
- ord-5ee15e6a40e3426eaf1e1579e35d49e4
- Source dataset
- uspto-grants-1996_10
- Patent number
- US05565473
Reaction notes
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