Imidazole → HCID 10856967, compound

To a solution of (R)-(+)-methyl lactate (2.95 g, 28.34 mmol) in DMF (20 mL) was added tert-butyldimethyl silyl chloride (6.41 g, 42.51 mmol) and imidazole (6.75 g, 99.18 mmol). After stirring at a room temperature for 18 hr, the reaction mixture was diluted with a saturated aqueous NaCl solution (90 mL) and extracted with petroleum ether (3×60 mL). The organic layer was washed with a cold 3% HCl solution (30 mL) and a saturated aqueous NaCl solution (30 mL), dried over Na2SO4 and concentrated. The remaining residue was purified by silica gel (105 g) with petroleum ether (300 mL), followed by 3% ethyl acetate in petroleum ether (600 mL). The 3% ethyl acetate in the petroleum ether fractions was collected and the solvent was removed to give 5.26 g of (R)-(+)-Methyl 2-(tert-butyldimethylsilyloxy)propanoate as colorless oil (85% yield). 1H NMR (CDCl3): δ 4.26 (q, 1H, J=6.8 Hz, —CH), 3.65 (s, 3H, —OCH3), 1.32 (d, 3H, J=6.8 Hz, —CH3), 0.83 (s, 9H, Si—(CH3)3), 0.03 (s, 3H, Si—CH3), 0.00 (s, 3H, Si—CH3).

1. extractionextracted with petroleum ether (3×60 mL)
2. washThe organic layer was washed with a cold 3% HCl solution (30 mL)
3. dry with materiala saturated aqueous NaCl solution (30 mL), dried over Na2SO4
4. concentrationconcentrated
5. customThe remaining residue was purified by silica gel (105 g) with petroleum ether (300 mL)
6. customThe 3% ethyl acetate in the petroleum ether fractions was collected
7. customthe solvent was removed

ORD record

ord-29bb70d773974f25adce9bbfada3b738

Source dataset

uspto-grants-2012_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08168648B2