反应详情

温度

10 °C

To a solution of diisopropylamine (1.8 mL, 12.6 mmol) in 30 mL THF at −78° C. was added n-butyllithium (1.6 M soln in hexanes, 7.6 mL, 12.1 mmol), and the mixture stirred 10 minutes at which time (4R, 5S)-4-Methyl-3-((R)-4-methyl-octanoyl)-5-phenyl-oxazolidin-2-one (3.2 g, 10.1 mmol) in 10 mL THF was added dropwise. The solution was stirred for 30 minutes, t-butyl bromoacetate (1.8 mL, 12.1 mmol) was added quickly dropwise at −50° C., and the mixture was allowed to warm slowly to 10° C. over 3 hours. The mixture was partitioned between Et2O and sat. NH4Cl (aq), the phases were separated, and the organic phase dried (MgSO4), and concentrated. The residue was purified by flash chromatography (16:1 to 8:1 hexanes:EtOAc) to provide 2.65 g (61%) of the titled compound as a colorless crystalline solid, mp=84-86° C. [δ]D23+17.1 (c=1.00, CHCl3).

1. additionwas added dropwise
2. customThe mixture was partitioned between Et2O and sat. NH4Cl (aq)
3. customthe phases were separated
4. dry with materialthe organic phase dried (MgSO4)
5. concentrationconcentrated
6. customThe residue was purified by flash chromatography (16:1 to 8:1 hexanes:EtOAc)