反应详情

A solution of 50% aqueous H2O2 (0.15 mL, 2.6 mmol) was added to a solution of (2R,5S)-2-benzyl-1,6-bis((S)-4-benzyl-2-oxooxazolidin-3-yl)-5-methylhexane-1,6-dione (250 mg, 0.43 mmol) in THF (3 mL) and water (1 mL) at 0° C. After 5 min of stirring, LiOH.H2O (54.1 mg, 1.29 mmol) was added and the reaction mixture was stirred for 1 hr at rt. Saturated aqueous Na2SO3 (0.2 mL) and saturated aqueous NaHCO3 (0.2 mL) were added and the reaction mixture was concentrated to remove the organic solvent. The aqueous solution was extracted with DCM (3 mL) to remove organic impurities. The aqueous phase was then acidified using aqueous 5 N HCl to pH<2. The cloudy mixture was extracted with DCM (2×2 mL). The organic extracts were combined, dried over Na2SO4 and concentrated to give (2R,5S)-2-benzyl-5-ethylhexanedioic acid (80 mg, 0.31 mmol, 71% yield) as a white solid. Anal. Calcd. for C15H20O4 m/z 264.1. found: 263.2 (M−); 1H NMR (400 MHz, CDCl3) δ ppm 7.30-7.28 (m, 2H), 7.22-7.16 (m, 3H), 2.99 (m, 1H), 2.74 (m, 1H), 2.66-2.63 (m, 1H), 2.26-2.23 (m, 1H), 1.72-1.25 (m, 6H), 0.91 (t, J=7.2 Hz, 3H).

1. stirringthe reaction mixture was stirred for 1 hr at rt
2. concentrationthe reaction mixture was concentrated
3. customto remove the organic solvent
4. extractionThe aqueous solution was extracted with DCM (3 mL)
5. customto remove organic impurities
6. extractionThe cloudy mixture was extracted with DCM (2×2 mL)
7. dry with materialdried over Na2SO4
8. concentrationconcentrated