Sodium Hydroxide → 4-[3-[6-(3-Benzo[1,3]dioxol-5-yl-5-methanesulfonyl-phenoxy)-hexyl]-2-(2-carboxy-ethyl)-phenoxy]-butyric acid

Participants

Reaction Conditions

Reaction Steps

To a solution of the 4-[3-[6-(3-benzo[1,3]dioxol-5-yl-5-methanesulfonyl-phenoxy)-hexyl]-2-(2-ethoxycarbonyl-ethyl)-phenoxy]-butyric acid ethyl ester (26.7 g, 39.1 mmol) in THF (200 mL) and ethanol (200 mL) was added aqueous 1.0 N sodium hydroxide (200 mL) at room temperature. The resulting suspension was heated to 45-50° C. and the mixture was stirred for 30 min and then cooled to room temperature and stirred for 15 h at which time TLC analysis of the mixture indicated the absence of starting material. Then, the reaction mixture was concentrated and the residue was diluted with water (200 mL) and extracted with diethyl ether (150 mL) to remove any neutral impurities. The aqueous layer was acidified with 1.0 N hydrochloric acid and the precipitated white organic compound was extracted into ethyl acetate (2×200 mL). The combined ethyl acetate extracts were washed with brine solution (300 mL) and the organic layers were dried over anhydrous magnesium sulfate. Filtration of the drying agent and removal of the solvent afforded the crude product which was dissolved in acetonitrile (270 mL) at hot condition and was stored in the refrigerator. The resulting white solids were collected by filtration and washed with acetonitrile. After air-drying, 4-[3-[6-(3-benzo[1,3]dioxol-5-yl-5-methanesulfonyl-phenoxy)-hexyl]-2-(2-carboxy-ethyl)-phenoxy]-butyric acid (19.7 g, 80.5%) was isolated as a white solid. ES(+)-HRMS m/e calcd for C33H38O10S (M+Na)+ 649.2078, found 649.2076.

Provenance & Evidence