Lithium hydroxide, monohydrate → {4-[1-(4-Chloro-benzenesulfonyl)-piperidin-4-yl]-6-fluoro-naphthalen-2-yl}-acetic acid

Participants

Reaction Steps

To a stirred solution of {4-[1-(4-chloro-benzenesulfonyl)-piperidin-4-yl]-6-fluoro-naphthalen-2-yl}-acetic acid methyl ester (80 mg, 0.17 mmol) in THF (4 mL) was added a solution of lithium hydroxide monohydrate (35 mg, 0.83 mmol) in water (1 mL) and the reaction mixture was stirred for 24 h at RT. 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 {4-[1-(4-chloro-benzenesulfonyl)-piperidin-4-yl]-6-fluoro-naphthalen-2-yl}-acetic acid (57 mg, 65%) as an off-white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 12.27 (br s, 1H), 7.95 (dd, J=9.0, 6.1 Hz, 1H), 7.88 (d, J=10.3 Hz, 1H), 7.76-7.85 (m, 4H), 7.68 (s, 1H), 7.34-7.41 (m, 2H), 3.80 (d, J=11.2 Hz, 2H), 3.71 (s, 2H), 2.59 (t, J=11.2 Hz, 2H), 1.87-1.94 (m, 3H), 1.73-1.82 (m, 2H); MS cald. for C23H20ClFNO4S [(M−H)−]: 460, obsd. 460.3.

Provenance & Evidence