Hydrochloric Acid → HCID 131730475, compound

Participants

Reaction Conditions

Reaction Steps

Trans-methyl 4-(3-ethoxy-3-oxopropanoyl)-2-(4-(trifluoromethoxy)benzyl)piperidine-1-carboxylate (679 mg, 1.57 mmol) (from example 113, step 1) was dissolved in MeOH (10 mL) and cooled to −40° C. under nitrogen. Sodium hydroxide (0.463 mL, 1.57 mmol) dissolved in water (1.000 mL) was added during 10 min and the yellow solution continued to stir at −40° C. for 20 min. Hydroxylamine (50% by weight in water, 0.096 mL, 1.57 mmol) was added during 8 min. The resulting solution was stirred at −40° C. for 3 h 15 min. The mixture was then rapidly poured into a prewarmed (80° C.) solution of 6 M hydrogen chloride (8.11 mL, 48.63 mmol) and the mixture continued to stir at 80° C. for 20 min. The solvent was evaporated and DCM/water added. The phases were separated and the organic phase passed through a phase separator and evaporated to yield a white solid. Crude trans-methyl 4-(3-oxo-2,3-dihydroisoxazol-5-yl)-2-(4-(trifluoromethoxy)benzyl)piperidine-1-carboxylate (603 mg, 96%) was isolated. MS m/z 401 (M+H)+

Provenance & Evidence