Lithium hydroxide, monohydrate → {6-Fluoro-4-[1-(pyridine-3-sulfonyl)-piperidin-4-yl]-naphthalen-2-yl}-acetic acid

Participants

Reaction Steps

To a stirred solution of {6-fluoro-4-[1-(pyridine-3-sulfonyl)-piperidin-4-yl]-naphthalen-2-yl}-acetic acid methyl ester (85 mg, 0.19 mmol) in THF (6 mL) was added a solution of lithium hydroxide monohydrate (40 mg, 0.95 mmol) in water (1.5 mL) and the reaction mixture was stirred for 24 hours at room temperature. The reaction mixture was concentrated under reduced pressure and washed with diethyl ether (3×5 mL). The washings were discarded. Water (5 mL) was added to the residue, and the mixture acidified (pH ˜2-3) with an aqueous solution of hydrochloric acid (2 N) and extracted with ethyl acetate (3×5 mL). The combined organic extracts were dried over Na2SO4 and evaporated under reduced pressure to give {6-fluoro-4-[1-(pyridine-3-sulfonyl)-piperidin-4-yl]-naphthalen-2-yl}-acetic acid (60 mg, 73%) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 12.38 (br s, 1H), 8.87-9.04 (m, 1H), 8.21 (d, J=7.1 Hz, 1H), 7.77-7.99 (m, 2H), 7.68 (br. s., 2H), 7.35 (br. s., 2H), 3.91 (d, J=11.6 Hz, 2H), 3.71 (s, 2H), 1.96 (d, J=12.1 Hz, 3H), 1.78 (d, J=11.6 Hz, 3H); MS cald. for C22H22FN2O4S [(M+H)+]: 429, obsd. 429.2.

Provenance & Evidence