反应详情

To a stirring aqueous mixture cooled to 0° C. comprising (S)-4-benzyl-3-((S)-2-methyl-5-phenylpentanoyl)oxazolidin-2-one (21mb(i), 563 mg, 1.60 mmol) was added hydrogen peroxide and lithium hydroxide. The resulting reaction mixture was stirred for four hours. The reaction mixture was acidified with 5% KHSO4 and extracted twice with ethyl acetate, the organic layer was washed twice with brine, dried over sodium sulfate, and concentrated under vacuum. The residue was purified by silica gel chromatography. Elution with ethyl acetate-heptane-acetic acid (25:75:0.4) afforded the title compound (293 mg, 95%) as a colorless oil; TLC Rf 0.35 (solvent system: 25:75:0.4 v/v/v ethyl acetate-heptane-acetic acid); HPLC retention time 12.08 min, stationary phase: Chiralpak IA 4.6×25 mm 5μ, ultraviolet detector at 210 nm, mobile phase: 1 mL/min 99:1:0.1 heptane: 2-propanol:acetic acid, 97.22% (S), 2.78% (R).

1. customThe resulting reaction mixture
2. extractionextracted twice with ethyl acetate
3. washthe organic layer was washed twice with brine
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated under vacuum
6. customThe residue was purified by silica gel chromatography
7. washElution with ethyl acetate-heptane-acetic acid (25:75:0.4)