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

Participants

Reaction Steps

Lithium hydroxide monohydrate (0.06 g, 1.6 mmol) was added to a stirred solution of {6-fluoro-3-methyl-4-[4-(piperidine-1-sulfonyl)-phenyl]-naphthalen-2-yl}-acetic acid methyl ester (0.186 g, 0.39 mmol) in a 3:1 mixture of THF—H2O mixture (16 mL). The reaction mixture was stirred for 16 hours at room temperature. The reaction mixture was concentrated to remove THF, and the crude material was diluted with water, acidified [pH˜2] with a 6 N aqueous solution of hydrochloric acid. The mixture was extracted twice with ethyl acetate. The collected organic layers were washed with water and brine, dried over anhydrous Na2SO4, and concentrated under reduced pressure to give the crude product. Trituration with hexane afforded {6-fluoro-3-methyl-4-[4-(piperidine-1-sulfonyl)-phenyl]-naphthalen-2-yl}-acetic acid (0.17 g, 94%) as a solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 12.39-12.68 (br. s, 1 H), 8.02 (dd, J=8.80, 6.20 Hz, 1 H), 7.88-7.92 (m, 3 H), 7.52 (d, J=8.31 Hz, 2 H), 7.39 (td, J=8.80, 2.40 Hz, 1 H), 6.71 (dd, J=11.00, 2.00 Hz, 1 H), 3.85 (s, 2 H), 3.01 (m, 4 H), 2.07 (s, 3 H), 1.54-1.64 (m, 4 H), 1.39-1.47 (m, 2 H). MS calcd. for C24H23FNO4S [(M−H)−] 440, obsd. 440.3.

Provenance & Evidence