Methanol → 3-Cyclopentyl-2-(4-fluoro-3-trifluoromethyl-phenyl)-propionic acid methyl ester

Temperature

25 °C

A solution of 3-cyclopentyl-2-(4-fluoro-3-trifluoromethyl-phenyl)-propionic acid (prepared as in Example 87A, 7.77 g, 25.3 mmol) in methanol (50 mL) was treated slowly with concentrated sulfuric acid (0.01 mL). The resulting reaction mixture was heated under reflux for 24 h. The reaction mixture was allowed to cool to 25° C. and then concentrated in vacuo. The residue was dissolved in ethyl acetate (75 mL). The organic layer was washed with a saturated aqueous sodium bicarbonate solution (1×50 mL), water (1×50 mL), and a saturated aqueous sodium chloride solution (4×50 mL). The organic layer was then dried over magnesium sulfate and sodium sulfate, filtered, and concentrated in vacuo to afford 3-cyclopentyl-2-(4-fluoro-3-trifluoromethyl-phenyl)-propionic acid methyl ester (8.48 g, 87.5%) as yellow oil: EI-HRMS m/e calcd for C16H18F4O2 (M+) 318.1243, found 318.1240.

1. customThe resulting reaction mixture
2. temperaturewas heated
3. temperatureunder reflux for 24 h
4. concentrationconcentrated in vacuo
5. dissolutionThe residue was dissolved in ethyl acetate (75 mL)
6. washThe organic layer was washed with a saturated aqueous sodium bicarbonate solution (1×50 mL), water (1×50 mL)
7. dry with materialThe organic layer was then dried over magnesium sulfate and sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated in vacuo

ORD record

ord-3b9b196ae3524cb9bf534dcc6a1b2346

Source dataset

uspto-grants-2003_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06610846B1