Hydrochloric Acid → HCID 131730495, compound

Participants

Reaction Conditions

Reaction Steps

Trans-methyl 4-(3-ethoxy-3-oxopropanoyl)-2-(3-fluoro-5-(trifluoromethyl)benzyl)piperidine-1-carboxylate (0.75 g, 1.73 mmol) (from example 137, step 1) was dissolved in MeOH (15 mL) and cooled to −40° C. Sodium hydroxide (0.073 g, 1.82 mmol) dissolved in water (1 mL) was added over 1 min and the resulting solution was stirred at −40° C. for 20 min. Then hydroxylamine (50% by weight in water, 0.115 mL, 1.88 mmol) was added over 1 min and stirring continued at −40° C. for 2 h 20 min. The reaction mixture was then transferred into a prewarmed (80° C.) solution of 6 M hydrogen chloride (30 mL, 180.00 mmol) and the mixture was continued to be stirred at 80° C. for 1 h. Then cooled to room temperature. Methanol was evaporated, then water was added. Extracted three times with DCM. Combined organic layers dried over MgSO4 and evaporated. Trans-methyl 2-(3-fluoro-5-(trifluoromethyl)benzyl)-4-(3-oxo-2,3-dihydroisoxazol-5-yl)piperidine-1-carboxylate (658 mg, 95%) was isolated as an off-white solid. MS m/z 403 (M+H)+

Provenance & Evidence