Hydrochloric Acid → HCID 131730484, compound

Participants

Reaction Conditions

Reaction Steps

Trans-methyl 2-(2,5-difluorobenzyl)-4-(3-ethoxy-3-oxopropanoyl)piperidine-1-carboxylate (0.611 g, 1.59 mmol) (from example 124, step 1) was dissolved in MeOH (5 mL) and cooled to −40° C. under nitrogen. Sodium hydroxide (0.064 g, 1.59 mmol) dissolved in water (0.500 mL) was added during 10 min and the colourless solution continued to stir at −40° C. for 20 min. Hydroxylamine (50% by weight in water, 0.098 mL, 1.59 mmol) was added during 8 min. The resulting solution was stirred at −40° C. for 3 h. The mixture was then transferred into a prewarmed (80° C.) solution of 6 M hydrogen chloride (8 mL, 48.00 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 crude trans-methyl 2-(2,5-difluorobenzyl)-4-(3-oxo-2,3-dihydroisoxazol-5-yl)piperidine-1-carboxylate (0.552 g, 98%) as a yellow semi-solid. MS m/z 353 (M+H)+

Provenance & Evidence