4'-Fluoroacetophenone → 5-(4-Fluoro-phenyl)-isoxazole-3-carboxylic acid {2-oxo-2-[4-(3-trifluoromethyl-phenoxy)-piperidin-1-yl]-ethyl}-amide

Participants

Reaction Steps

DIPEA (131 mg, 1.0 mmol) was added to a stirred solution of 5-(4-fluoro-phenyl)-isoxazole-3-carboxylic acid (60 mg, 0.29 mmol) (prepared by the method used for the synthesis of Intermediate 25, starting from 4′-fluoroacetophenone) in DMF (2 mL) followed by HOBt (41 mg, 0.3 mmol) and EDCI.HCl (58 mg, 0.3 mmol). After 2 minutes 2-amino-1-[4-(3-trifluoromethyl-phenoxy)-piperidin-1-yl]-ethanone hydrochloride (125 mg, 0.37 mmol) (prepared according to Step 1 and 5 of the General Scheme) was added to the reaction mixture and stirring was continued at ambient temperature overnight. The reaction mixture was diluted with cold water, extracted with ethyl acetate, dried over sodium sulfate and concentrated under reduced pressure. Purification by recrystallisation from chloroform afforded 77 mg (54.2% Yield) of 5-(4-fluoro-phenyl)-isoxazole-3-carboxylic acid {2-oxo-2-[4-(3-trifluoromethyl-phenoxy)-piperidin-1-yl]-ethyl}-amide. LC/MS [M+H]+: 492, 96.7%. 1H NMR (300 MHz, DMSO-d6): δ8.62 (t, 1H), 8.0 (m, 2H), 7.5 (t, 1H), 7.38 (m, 3H), 7.26 (t, 3H), 4.8 (m, 1H), 4.2 (d, 2H), 3.7 (m, 4H), 3.4 (m, 2H), 2.0 (m, 2H), 1.6 (m, 2H).

Provenance & Evidence