Methanol → 4-[5-(3,5-Dichlorophenyl)-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-1-naphthalenecarboxylic acid

Participants

Reaction Steps

A solution of lithium hydroxide monohydrate (350 mg, 8.34 mmol) in water (10 mL) was added to a stirred solution of methyl 4-[5-(3,5-dichlorophenyl)-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-1-naphthalenecarboxylate (i.e. the product of Step B, 650 mg, 1.39 mmol) in tetrahydrofuran (10 mL), followed by the addition of methanol (10 mL). The resulting mixture was stirred overnight at room temperature and then partitioned between water and diethyl ether. The aqueous layer was acidified with 6 N aqueous hydrochloric acid to pH 2 and extracted with ethyl acetate. The combined organic extracts were washed with brine, dried over sodium sulfate, and concentrated under reduced pressure to provide the title compound as a white solid (450 mg). 1H NMR (CDCl3): δ 9.08 (d, 1H), 8.80 (d, 1H), 8.31 (d, 1H), 7.71 (m, 2H), 7.57 (m, 3H), 7.46 (dd, 1H), 4.28 (d, 1H), 3.91 (d, 1H).

Provenance & Evidence