Lithium Hydroxide → 3-Cyclopentyl-2-(4-methanesulfonyl-3-trifluoromethyl-phenyl)-propionic acid

A solution of 3-cyclopentyl-2-(4-methanesulfonyl-3-trifluoromethyl-phenyl)-propionic acid methyl ester (prepared as in Example 89A, 2.92 g, 7.72 mmol) in tetrahydrofuran/water (88 mL, 3:1) was treated with lithium hydroxide (647 mg, 15.43 mmol). The reaction was stirred at 25° C. for 3 d. The tetrahydrofuran was then removed in vacuo. The residue was diluted with water (50 mL) and extracted with ether (25 mL). The aqueous layer was acidified to pH=1 with a 3N aqueous hydrochloric acid solution. The product was extracted into ethyl acetate (3×75 mL) and ether (1×50 mL). The combined organic layers were washed with a saturated aqueous sodium chloride solution (2×100 mL), dried over magnesium sulfate and sodium sulfate, filtered, and concentrated in vacuo to give 3-cyclopentyl-2-(4-methanesulfonyl-3-trifluoromethyl-phenyl)-propionic acid (2.37 g, 84.5%) as a pale-yellow semi-solid: EI-HRMS m/e calcd for C16H19F3O4S (M+) 364.0956, found 364.0958.

1. customThe tetrahydrofuran was then removed in vacuo
2. additionThe residue was diluted with water (50 mL)
3. extractionextracted with ether (25 mL)
4. extractionThe product was extracted into ethyl acetate (3×75 mL) and ether (1×50 mL)
5. washThe combined organic layers were washed with a saturated aqueous sodium chloride solution (2×100 mL)
6. dry with materialdried over magnesium sulfate and sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo

ORD-Eintrag

ord-0a48e5607cda4cd4ab1a1c373f7fcf8a

Quelldatensatz

uspto-grants-2005_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06951945B2