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

Participants

Reaction Steps

To a stirred solution of {6-fluoro-4-[1-(toluene-4-sulfonyl)-piperidin-4-yl]-naphthalen-2-yl}-acetic acid methyl ester (70 mg, 0.2 mmol) in THF (4 mL) was added a solution of lithium hydroxide monohydrate (32 mg, 0.76 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 [{6-fluoro-4-[1-(toluene-4-sulfonyl)-piperidin-4-yl]-naphthalen-2-yl}-acetic acid (52 mg, 77%) as an off-white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 12.37 (br s, 1H), 7.94 (dd, J=8.8, 6.4 Hz, 1H), 7.88 (d, J=10.3 Hz, 1H), 7.66-7.73 (m, 3H), 7.50 (d, J=8.3 Hz, 2H), 7.33-7.42 (m, 2H), 3.79 (d, J=12.2 Hz, 2H), 3.71 (s, 2H), 1.90 (d, J=11.7 Hz, 2H), 1.69-1.82 (m, 1H); MS cald. for C24H25FNO4S [(M−H)−]: 440, obsd. 440.4.

Provenance & Evidence