反应详情

To a solution of (S)-(−)-ethyl 2-(tert-butyldimethylsilyloxy)propanoate (10.0 g, 43.04 mmol) in THF (430 mL) at 0° C. was added an aqueous LiOH solution (0.2 M, 430 mL). After stirring at room temperature for 5 hr, the reaction mixture was concentrated to 50% of the original volume and extracted with petroleum ether (2×80 mL). The ether extracts were combined and extracted with a saturated aqueous NaHCO3 solution (80 mL). The aqueous layers were combined and acidified to pH 3 to 4 with an aqueous KHSO4 solution (1 M, 175 mL). The aqueous solution was extracted with petroleum ether (3×300 mL) and the combined organic layers were dried over Na2SO4 and concentrated to afford 6.96 g of (S)-(−)-2-(tert-butyldimethylsilyloxy)propanoic acid as colorless oil (79% yield). 1H NMR (CDCl3): δ 4.26 (q, 1H, J=6.8 Hz, —CH), 1.35 (d, 3H, J=6.8 Hz, —CH3), 0.82 (s, 9H, Si—(CH3)3), 0.03 (s, 3H, Si—CH3), 0.02 (s, 3H, Si—CH3).

1. concentrationthe reaction mixture was concentrated to 50% of the original volume
2. extractionextracted with petroleum ether (2×80 mL)
3. extractionextracted with a saturated aqueous NaHCO3 solution (80 mL)
4. extractionThe aqueous solution was extracted with petroleum ether (3×300 mL)
5. dry with materialthe combined organic layers were dried over Na2SO4
6. concentrationconcentrated